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ED CRAIG. www.weldreality.com.

The world's largest website on MIG - Flux Cored - TIG Welding


Pulsed MIG. Page .1.

Advanced TIP TIG Welding
TIP TIG Welding is always better quality than TIG and 100 to 500% faster with superior quality than TIG - MIG - FCAW.

 
 
   

 


Ed Craig and www.weldreality.com
E Mail ecraig@weldreality.com


Pulsed MIG Welding.




MIG Weld Equipment and Pulsed MIG Weld Reality.

As this site is updated frequently please
refresh each page before you start.




If you want to read how pulsed MIG caused major weld cracks
on Ford truck axles, continue to pulsed section 2. (bottom of page).




Aisan and European management love to waste money on useless
pulsed MIG weld equipment electronic bells & whistles.


Large Aisan, European and North American companies have for decades payed a huge price for weld process management ignorance
. It's especially ironic that in 2014, in Asia, where weld labor costs are typically low, that you will find the majority of large weld - fabrication companies are demanding very expensive Chinese made pulsed MIG equipment. The sopisticated electronic, Pulsed MIG equipment typically costs $6,000 to $15,000. It's a weld reality that In 2014, as it's been for at least 25 years, most of the weld shop managers who make the Pulsed MIG equipment purchase decisions, are rarely aware that the sophisticated, pulsed equipment, will in contrast to a $3,000 to $4000, well made, regular CV, MIG power source, will result in the following:

PLEASE REMEMBER THAT THE PRIME PURPOSE OF ANY WELD IS TO FULLY FUSE TWO OR MORE METAL COMPONENTS TOGETHER.

[a] The costly, pulsed MIG units will on most welded parts > 2.5 mm, produce welds with less weld fusion and welds with more porosity. The reason for the pulsed MIG weld fusion and porosity concerns is a simple one. Those pulsed MIG welds will typically spends 50% of their arc on time, with a pulsed back ground current of less than 100 amps.

In contrast to the traditional, open arc, Spray weld from a low cost Constant Voltage MIG unit, It's logical that any pulsed weld will put in less weld energy. For those that want proof, it takes five minutes. First make sure your weld personnel are trained to set optimum MIG spray settings with a CV MIG power source. (if they can't answer the MIG weld questions at the top of the page, they are not trained). On clean (no mill scale 3/8 - 1/2 steel test plates, have the welders produce a single pass, 1/4, (6 mm), horizontal, spray fillet weld. Section both the spray and pulsed welds in the middle, and examine the weld fusion and porosity in both the weld cross sections..


[b] A key characteristic of a Pulsed MIG weld, is with the "lower open arc weld energy potential" than a conventional MIG spray weld,the pulsed mode will benefit specific, limited, manual, heat sensitive applications such as weld cladding (require low weld dilution) and thin heat sensitive, < 3 mm aluminum welds. Pulsed MIG benefits are also attained with automated all position, pipe welds, in which the MIG wire stickout, the weld travel speeds, and the weld weaves are controlled. The weld shop reality however is that 99% of all manual MIG welds, will with low cost argon 2 - 20% CO2 mixes, achieve the highest posssible weld quality, (with minimal spatter) at the lowest possible weld costs. However the MIG spray welds, will rarely be attained by weld personnel that play around with their weld controls. To optimize MIG - FCA weld quality - productivity has never required sophisticated MIG equipment or three part gas mixes, theses welds simply need to be made by individuals who have recieved training in MIG - FCA weld process controls and best weld practices.

MOST WELD SALES REPS, EITHER DON'T KNOW, OR DON'T WANT THEIR CUSTOMERS TO KNOW THAT THE HIGHEST MIG WELD QUALITY AND PRODUCTIVITY CAN BE MADE BY LOW COST MIG EQUIPMENT AND GAS MIXES.

As the weld parameters can change with every different Pulsed MIG power source, weld procedure qualification typically means little with the pulsed MIG process.

By the way, I know that few companies have given consideration to the fact that each new pulsed MIG unit bought into the plant should typically require a new, costly, weld re-qualification of existing weld procedures. Again the reasons for the re-qualification of the welds, is every new model of pulsed MIG equipment will typically will have major electronic changes, and for a given wire feed rate the pulsed output changes could dramatically impact the weld energy produced. The bottom line is this. If for example your company spent thousands of dollars on a pulsed MIG weld application qualification 5 yrs ago, and then they purchase that new pulsed MIG equipment today they should take a look at requirements of the weld codes that typically don't allow changes in essential weld variables.

I predict that not worrying about weld fusion changes from pulsed equipment changes and not re-qualifying the pulsed welds with that new pulsed equipment, is just another one of those weld shop concerns that one day will have dramatic weld failure, and costly weld cost liability consequences for some companies.


[c] That new, overpriced pulsed MIG weld equipment will in many instances rarely get through it's short warranty period without circuit board issues that will likely impact your companies weld quality - productivity. When the pulsed unit does require repairs, expect to pay thousands of dollars, and pray it wont take more than a month or two to repair. Please also be aware that your organization added to the pulsed equipment longevity and durability concerns when the pulsed equipment purchased was made in China. With Chinese pulsed MIG units I believe you should expect extensive costly repair and weld performance and weld quality issues. In contrast, that low cost, regular, USA made MIG equipment should typically be in weld shop service, without requiring repairs, for 10 to 25 years. Also note most electricians should have the ability to repair regular CV equipment at low costs.

I have evaluated global pulsed MIG equipment for approx three decades. I have written over 100 pages in, "My Management - Engineers Guide To MIG" book, on what's wrong with the Pulsed MIG process and my Process Control training programs, also tell you what's wrong with the pulsed equipment, and at the same time how to get the best out of a pulsed MIG unit. The reality is for the majority of ferrous and none ferrous weld applications, will be the only companies that benefit from pulsed MIG equipment sales, are the companies that make and sell pulsed MIG units.

The reason managers and engineers around the globe buy into the pulsed hype is the too common weld shop reliance on salesmanship for MIG equipment advice, and of course also the general weld process control - best practices ignorance. So instead of wasting many thousands of dollar in the purchase of that pulsed MIG unit, I would recommend the weld shop purchase of a well made USA Miller - Lincoln. CV $3000 - $4000 350 - 450 CV MIG power source. If selecting European CV equipment consider ESAB CV units. To get the best out of this equipment I would advice you to spend a whopping $400 on my MIG or Flux Cored Weld Process Controls - Best Weld Practices resources.

2013: PLEASE NOTE: PULSED MIG IS A DIFFERENT WELD PROCESS WHEN IT ATTAINS THE CONTROLLED WELD BENEFITS FROM WELD AUTOMATION: It's important that the weld industry understands the reasons why the pulsed MIG process when used with automation such as mechanized pipe units or with robots. With automation controls, pulsed MIG can produce superior vertical up weld quality than the welds made with conventional CV equipment.

The conventional, open arc, MIG spray transfer welds provide high weld energy and the welds are usually too fluid to control for most vertical up weld applications. In contrast the pulsed mode provides lower weld energy open arc welds that solidify at a more rapid rate than a spray weld. The faster freeze, lower energy pulsed welds as many in the oil and energy industries are aware, will often on manual vertical up pipe applications create welds with lack of weld fusion.

When a high deposition, moderate energy process such as Pulsed MIG is used for all position, manual welds, the welds are made at much faster weld speeds than the TIG - SMAW and sometimes the FCAW process. The faster pulsed MIG weld speeds with the inconstant manual weld weave techniques and inconsistent weld speeds will often result in lack of fusion and porosity defects

In contrast when we see pulsed MIG used with costly, mechanized, pipe applications, you can apply controls to the process so the welds can be made to meet the pipe weld code requirements

When dealing with mechanized, pulsed MIG pipe weld equipment as found with oil industry pipe applications, you will often find multi-gun units with sophisticated pulsed weld equipment and controls. The automated, pulsed equipment will provide dedicated pulsed MIG weld programs suited to the unique requirements necessary for the pipe weld roots, fill and cap passes. The message here is two fold. [1] All position mechanized pipe welds are a fraction of one percent of all MIG welds. [2] Don't expect the weld results you will attain from the automated pulsed MIG process, with the weld quality results you will achieve from the manual pulsed MIG process

SINCE IT'S INTRODUCTION IN THE EIGHTIES, I HAVE BEEN EVALUATING PULSED MIG EQUIPMENT FROM GLOBAL MIG EQUIPMENT MANUFACTURERS. IN MY HANDS ON WELD TESTS OVER THE 3 DECADES, I SAW THAT THE ELECTRONIC DIFFERENCES AND RESULTING PULSED ARC CHARACTERISTICS BETWEEN ONE PULSED MIG EQUIPMENT MANUFACTURER AND ANOTHER MANUFACTURER, WERE EXTENSIVE. IN 2014 LITTLE HAS CHANGED.

BACK TO THE REAL WORLD: FOR FIVE PLUS DECADES. AS IT STILL IS TODAY IN 2014, LOW COST, WELL DESIGNED USA - AND SOME EUROPEAN, (NOT EASTERN) BUILT, CONSTANT VOLTAGE, (CV) MIG EQUIPMENT, HAS PROVIDED A MODERATE TO STEEP SLOPE WHICH PROVIDES THE CURRENT NECESSARY FOR THE WORLD'S MOST COMMON MIG WIRES. WHY IS THIS IMPORTANT.

THINK ABOUT THOSE MILLIONS OF EXISTING, CV MIG WELD PROCEDURES DONE OVER THE LAST FIVE DECADES, THOSE PROCEDURES ARE USUALLY TUCKED AWAY IN A FILE IN THE QA MANAGERS OFFICE. WHEN YOU USE PULSED MIG, YOUR ORGANIZATION WILL HAVE THE HIGH COSTS ASSOCIATED WITH WELD PROCEDURE REQUALIFICATION. ALSO NOTE THAT WHEN YOU CHANGE THAT PULSED EQUIPMENT FROM ONE YEAR TO THE NEXT, THE OUT PUT WILL LIKELY BE VERY DIFFERENT, AND BY RIGHTS YOU SHOULD AGAIN SPEND THOUSANDS OF DOLLARS ON AGAIN REQUALIFYING THOSE WELDS.

THINK ABOUT THE FACT ALSO THAT ALL FLUX CORED WIRES WERE DEVELOPED WITH THE CV EQUIPMENT SLOPE AND RESULTING WELD ENERGY THATS GENERATED FOR SPECIFIC REQUIRED WIRE FEED SETTINGS. IF YOU USE PULSED AND SWITCH IT TO THE CV MODE, THE SLOPE ON THE PULSED EQUIPMENT TYPICALLY RESTRICS THE WELD CURRENT OUT SO YES YOU WILL PRODUCE NICE LOOKING FLUX CORED WELDS, HOWEVER THERE WILL TYPICALLY BE LESS WELD FUSION..

THE BOTTOM LINE. FOR DECADES DIFFERENT MIG EQUIPMENT MFGS HAVE PROVIDED 300 - 450 AMP CV, MIG POWER SOURCES AND THEY TYPICALLY HAVE HAD SIMILAR SLOPES AND THEREFORE SIMILAR WELD PERFORMANCE. (MILLER DELTA WELDS, AND IN THE OLD DAYS LINDE SVI EQUIPMENT WAS SIMPLY AND STILL IS THE BEST)

WITH THAT LOW COST CV EQUIPMENT, LIFE FOR THE WELD SHOP SHOULD HAVE BEEN SIMPLE, (IF PROCESS CONTROL TRAINING HAD BEEN PROVIDED FOR WELD PERSONNEL) WITH TWO CONTROLS, THE DURABLE CV EQUIPMENT COULD PROVIDE SHORT CIRCUIT, GLOBULAR OR SPRAY TRANSFER. LOW - MEDIUM - HIGH ENERGY WELDS SUITED TO THE MAJORITY OF ALL GLOBAL WELD APPICATIONS.


Ref pulsed MIG pipe welding concens:

API. 5.2.3 states that the Pulsed Gas Metal Arc Welding (GMAW-P) process may be used for any material thickness. However whenever the welding system is changed or the settings on existing equipment are "significantly altered", the fabricator should verify the reesulting weld properties. The extent of verification or testing should be as agreed between the purchaser and fabricator.

Response from Ed's MIG WELD REALITY. In contrast to the traditiona, two control, MIG or flux cored weld process, there are many weld essential variables that can be readily changed with the pulsed MIG mode. While the API code engineers warn against a "SIGNIFICANT change in a pulsed settings", the real world weld decision maker needs to be aware that an insignificant parameter change with the highly sensitive pulsed MIG mode, will have a significant influence on the weld fusion, and that weld fusion will in most instances will be marginal or lacking.

While on the subject of pulsed MIG, the API code does not discuss the mechanized versus manual pulsed welding inconsistencies. When a code body stipulates that a fusion sensitive process is OK for any pipe thickness, the code is sending the message that this process is acceptable for both manual and mechanized welds. With automated pulsed MIG pipe line welds, electronic power source features such as volt or current energy spikes can be applied to the weld weave dwell times. These increased energy spikes will impprove the pipe side wall weld fusion. Also the controlled pulsed MIG weld speeds, controlled mechanized weld weaves and constant wire stick out will have a lot to do with success of the mechanized pulsed MIG process when used for pipe line welds. Without these controls, for three decades the manual pulsed MIG weld process has proven that the attainment of 100% X-Ray all position pipe weld quality is a challenge, and this is a challenge that weld shops in 2013 do not have to face when they can use the far superior TiP TiG process.




Pipes and weld process choices..

Ten years ago STICK and FCAW were most common processes for pipe welds.


PULSED MIG AND PIPE PROJECTS: Large pipe projects especially in the oil industry will today often use a mechanized, multi-torch, pulsed MIG unit for the pipe welds. The pulsed MIG equipment may or may not have a level of electronic sophistication way beyond that available in standard pulsed equipment sold for manual pulsed weld applications.

For mechanized pipe root welds, either the MIG CMT - STT - RMD modes will typically be selected, and for the pipe fill - cap pass welds, the more conventional pulse mode will be selected. Apart from the dedicated pulsed programs for the pipe fill and cap passes with the pulsed equipment, you will also find the pulsed equipment and controls may enable unique pipe weld attributes. For example the equipment may have the capability to provide a current or volt spike during the weld dwell time in the weld weave cycle.

Vee and J groove pipe welds have simple weld requirements. Moderate MIG weld energy is required across the hot groove weld surface, and higher weld energy with dwell times is beneficial when applied to the Vee or J groove side walls, (the thicker the pipe the higher the side wall energy required). The weave dwell energy spike from this unique pulsed process can overcome the common pulsed MIG side wall (lack of weld fusion) weld issues, (a sophistication at this time not possible with manual pulsed pipe applications). Most large automated pipe applications will enable multi-MIG guns which also add more weld heat into the groove welds again improving the weld fusion potential. Mechanized pipe welds also provide Constant MIG Wire Stick Out and Constant Weld Travel Rates which enable improved weld process control and bring a weld quality uniformity and consistency to the automated weld that again is not be possible with the manual pulsed MIG pipe welds.

2103: LETS GET BACK TO WELD REALITY. AFTER TWENTY FIVE YEARS OF PAINFUL, MANUAL PULSED MIG EQUIPMENT EVOLUTION, DEPENDING ON WHO'S PULSED MIG EQUIPMENT WAS PURCHASED, MANY WELD SHOPS WILL HAVE PROCESS THAT CAN CAUSE MORE WELD ISSUES THAN IT RESOLVES:

In 2013 we now have in North America, a few pulsed MIG power sources that actually work in a consistent manner and may possibly get through their 36 month warranty period without circuit board or electronic issues. The question that needs to be asked when selecting pulsed for manual steel and alloy steel applications was the purchase of this sensitive process justified in contrast to the lower cost CV MIG equipment.

There are obvious weld benefits attained for pulsed MIG aluminum welds (alum require less weld energy than spray) and for specific MIG stainless welds that benefit from an open arc mode that enables lower weld heat than spray to possibly reduce distortion. Remember the key benefit of a MIG weld mode is the ability to provide consistent weld fusion, and on most weld applications, spray transfer will provide superior weld fusion than pulsed. Alway remember that Pulsed MIG is a process which spends 50% of its time at a back ground weld current of usually less than 100 amps. The pulsed process is also a good subsitute (in most instances not necessary) for the gague welds that are typically welded with short circuit, or when welding alloys that have poor weld transfer characteristics with conventional short circuit or spray transfer.

As many pipe welds shops have found out, ypically when pulsed MIG is used for "manual" pipe welds that require "100% X-Rays", a combination of variables and factors will come together and lack of weld fusion may become a common weld defect. In contrast to SMAW and TIG used for pipe welds, each hour pulsed MIG will typically provides at least 10 times more weld and is therefore considered a high deposition process. When it comes to MIG weld defects that high weld deposition rate takes a large part of the blame.



Fig. The outside appearence was irrelevant.


If you provide what you think is an optimum pulsed MIG fillet weld on 3/8 (9.6mm) steel plates and then provide a macro section of the fillet weld, you will often see either marginal or lack of side wall weld fusion. After the macro weld evaluation you may come away with the impression that with pulsed MIG, you have a weld process that provides a poor ratio of weld energy to the weld deposition - mass and the weld speeds provided. Also with manual pulsed MIG welds the weld energy is influenced and the weld transfer is disrupted by the manual wire stick out variations and the many different weld techniques that each welder brings to the pulsed weld.



THE RATIO OF THE WELD ENERGY DELIVERED AND THE WELD MASS AND WELD SPEEDS THAT RESULT IS ALSO AN ISSUE WITH MIG SPRAY TRANSFER, HOWEVER THE WELD SHOP NEEDS TO REMEMBER THAT WITH PULSED MIG THE WELD SPENDS 50% OF IT'S TIME WITH A BACK GROUND CURRENT < 100 AMPS.

WELD PROCESS EXPERTISE CAN OFTEN OVERCOME POOR WELD EQUIPMENT TECHNOLOGY. IN THE 1990s, I SET OPTIMUM PULSED WELDS ON THE WORLD'S MOST COMPLICATED ROBOT WELDS.


Fig.. The most complex welds are small pipe and tubes, that have difficult acces and 100% X-Ray


THE EASIEST PIPE WELDS TO MAKE ARE LARGE DIAMETER PIPES (EASIER TO FOLLOW THE RADIUS AND MORE TIME TO REACT). IN CONTRAST THE MOST COMPLEX PIPE WELDS ARE SMALL DIAMETER PIPES AND TUBES.

I remember in the 1990's, when the management team at one of the world's largest engineering companies decided to purchase a seven axis robot to weld it's boiler tubes to headers. The above picture is not the parts welded but similar and the tubers were slightly larger. The boiler head pipes were approx. 8 - 10 diameter, typically 20 to 40 feet long with the 2 - 3 inch diameter thinner wall tubes. The robot traversed on a track placed on the other side of the header. These complex ASME welds were typically carried out by the highest skilled manual TIG welders. I won't go into why the management should not have selected a costly robot for these welds, however I would like to tell you about the pulsed MIG welds I produced on this robot application.

For each boiler tube to head weld, two robot pulsed MIG weld layers were required to fill the grooves and produce the fillet around the header. The pulsed MIG welds had to pass 100 X-Ray as per the ASME requirements. As the robot could not go 360 degrees around the tubes each of the two weld layers was made with four passes so four weld start - stops was required for one layer, with a total of 8 start - stops for the completed 2 weld layers, by the way no grinding or human involvement was allowed for the weld layers.




THE PULSED TECHNOLOGY WAS ONLY 10 YEARS OLD. THE ELECTRONICS WERE STONE AGE AND NOT UP TO THE TASK SO I USED PROCESS EXPERTISE TO ACHIEVE THE ASME PIPE WELD QUALITY:

Can you remember how poor computers were in the early 1990s? well I want you to try and imagine how bad the global electronic pulsed MIG equipment was at that time. I had a sophisticated robot attached to to an inconsistent - erratic pulsed power source and had to provide optimum weld quality with vertical up, tube to header welds on two very different part thicknesses. In those small circular welds we had 8 weld starts and 8 weld stops that required perfect weld tie-ins to get past the X-Rays.



REMEMBER WITH SMALL DIAMETER MIG WELDED APPLICATIONS AND WITH SMALL WELD LENGTHS, THE WELD ARC ON TIMES MAY BE MEASURED IN A FEW SECONDS AND YOU NEED TO RELY ON THE WELD EQUIPMENT AND CONTROLS TO GO FROM WELD START DATA TO THE WELD DATA AND TO THE WELD END DATA IN THOSE FEW SECONDS. THE REALITY IS 2013 FEW AUTOMATED UNITS ARE GOOD AT PROVIDING THIS FUNCTION, SO IMAGINE WHAT WE HAD TO WORK WITH IN THE 1990s.


All the tube to header welds needed was one poor weld tie or lack of fusion and the ASME, 100% X-Rays would mark the weld as a failure. I used all my MIG weld process control expertise to make these robot welds work and produce an eight hour weld quality with better weld productivity and no more weld rework than that attained from the manual TIG welders. How did i solve the weld fusion - weld tie in issues?. For the side wall weld fusion I used robot weave dwell times and kept the pulsed MIG weld mass as thin as possible. For the weld start - stop tie-ins, with the robot weld end - start data, I used low wire feed than the weld with higher weld voltage which with carefullly selected dwell time provided good tie ins, (creating a dwell time energy spike) which is similar to what is today, >17 years later being used by oil companies and there much more conntrolled, sophisticated, pulsed MIG equipment. I trained a technician to make those robot welds and soon after he quit and I believe the robot was eventually put out to pasture. In 2013 the tube to header welds would still be a high risk robot application especially when you can now do these welds with the easy to use TiP TiG process. www.tiptigusa.com.




1990s.. Ed (left - right) comparing MIG short circuit versus the STT and RMD MIG weld modes on Imperial oil, nat gas pipe.





WELD CODES, CONFUSION OR INADEQUATE INFOMATION.

When it comes to MIG and flux cored welding, rather than providing weld process resolutions, most codes relevant to pipe welding will provide inadequate information or the information they provide simply adds to the global weld process myths and confusion.


Welding decision makers often look codes such as AWS - API and - ASME to provide practical, pipe welding advice and recommendations. Those individuals that that put all their faith in the codes that are governing the specific weld applications they are working on, need to be aware of a little weld reality, The weld information in these codes has too frequently been written and influenced by code committee individuals who lacked MIG / Flux Cored weld process controls & best practices / application expertise.


50 YEARS AFTER THE INTRODUCTION OF THE "MIG PROCESS",
AND 35 YEARS AFTER THE INTRODUCTION OF FLUX CORED ELECTRODES, THE PRIMARY WELD CODES WHEN ADVISING ON THESE PROCESSES STILL CREATE CONFUSION AND TOO MANY QUESTIONS.

API. 5.2.3 Pulsed Gas Metal Arc Welding (GMAW-P. This code states that the pulsed process may be used for any material thickness and whenever the welding system is changed or the settings on existing equipment are "significantly altered"then the fabricator should verify the weld properties. The extent of verification or testing should be as agreed between the purchaser and fabricator.

In a world in which engineering standards should apply, what the hell does significantly altered mean. In contrast to the traditionaL, two control, MIG or flux cored weld process, there are many weld essential variables that can be readily changed when utilizing the pulsed MIG mode. While the API code warns against a "SIGNIFICANT CHANGE" in a pulsed settings", the real world weld decision maker needs to be aware that an insignificant, small parameter change with the highly sensitive, manual pulsed MIG mode, can have a significant influence on the weld fusion attained.


 

While the code bodies in 2013 have very little negative to say about pulsed MIG process, for those of you with grey hair, you may remember that these same codes typically either did not allow regular MIG or the code weld specifications made incorrect recommendations or negative comments on the use of MIG. For example, for five decades, the MIG short circuit process has been treated like a leper, yet the weld reality was and still is in 2013, the Short Circuit mode is the best weld transfer mode for carbon steel, "rotated" pipe, open root welds.

Most of the pipe shops which were embedded with the SMAW and TIG process would typically not consider using the MIG spray transfer mode for rotated pipe welds, yet the reality has been that MIG spray transfer on the rotated pipe applications should provide superior weld fusion and less porosity than any pulsed MIG transfer.

THE POOR PULSED MIG WELD MASS TO WELD ENERGY RATIO:

What most weld decision makers and QA personnel are not aware, is that there is on most all position, pulsed MIG pipe weld applications thicker than 6mm, a poor ratio between the moderate pulsed MIG weld energy attained, (influenced by peak to low back ground current changes) and the high weld deposition rates that typically result. The healthy pulsed MIG weld deposition rates push the high weld speeds, (faster weld speeds don't help weld fusion) along with the resulting large weld mass (larger weld mass creates a hinderance to the weld energy produced).

For those of you moving aggressively forward with the manual pulsed MIG process for your all position pipe welds, do not be surprised even when using the highest manual welder skills, when you X-Ray those sluggish stainless or nickel alloys to find lack of fusion.

YOUR LOCAL SALES REP WONT TELL YOU THIS BECAUSE THEY ARE NOT AWARE OF IT. OPTIMUM PULSED MIG WELD FUSION WITH MANUAL WELDS WILL OFTEN BE CONSIDERED MARGINAL, AND MARGINAL WELD FUSION WILL BE MADE WORSE BY THE MANY PROCESS AND HUMAN VARIABLES THAT INFLUENCE THOSE MANUAL PULSED MIG WELDS.



THE CODE RULES SHOULD CHANGE WITH AUTOMATED PULSED MIG WELDS:

I am not aware of any code that discusses the mechanized versus manual pulsed welding differences and the weld quality consequences of those differences. When a code body puts it's stamp of approval on a weld process such as Pulsed MIG, the code is sending the message that this is process that's acceptable for both manual and mechanized pipe welds.

With automated pulsed MIG pipe line welds in which the use of multi-MIG guns is typical, electronic MIG power source features such as volt or current energy spikes can be applied to the weld weave dwell times. These controlled, increased weld energy spikes will improve the 5G pipe side wall weld fusion. Also the controlled pulsed MIG weld speed, the controlled, mechanized weld weaves and the constant wire stick out. are the automated features that will have a lot to do with success of the mechanized pulsed MIG process when used for pipe line welds. Take away these important controls and as it's been for three plus decades the manual pulsed MIG process has proven that the attainment of 100% X-Ray all position pipe weld quality is a challenge. By the way this is a challenge that weld shops in 2013 do not have to face when they can use the far superior TiP TiG manual or automated weld process
.



API. 5.2.2 Short Circuiting Gas Metal Arc Welding (GMAW-S). The use of GMAW-S shall be limited to the following conditions:

[] For vertical welding, the root pass and second pass progression for a material of any thickness may be either uphill or downhill.

Ed's response. There is no logic in using MIG short circuit, with the vertical up position on any weld application. Just as there is no logic in this cold process being used for the second pass which from a weld fusion potential is the most sensitive part of any pipe weld..


[]
The fill and cap pass for butt or fillet welds may be welded with the short circuit process, provided the thickness of any member does not exceed 3/8 in. (9.5 mm) and vertical welding is performed with uphill progression.

Ed's response. Watch out for lack of weld fusion with the short circuit process welding vert up on any steel parts > 1/8 (> 3 mm0..



Ed testing both the short circuit and STT process
for Imperial Oil. Weld focus at the difficult 5 to 7 o'clock positions.

 

LETS GET BACK TO 2013 AND MANUAL PULSED MIG WELDS. IT'S A SIMPLE FACT THAT IN AN INDUSTRY IN WHICH PLAYING AROUND WITH TWO SIMPLE MIG CONTROLS IS THE NORM, YOU WILL TOO FREQUENTLY FIND THAT WELD SALESMANSHIP OFTEN PLAYS A LARGE ROLL IN THE PULSED EQUIPMENT PURCHASE,



A point managers need to address when purchasing pulsed MIG equipment. Was the person who selected the pulsed MIG equipment in full control of the traditional MIG equipment that's been around for decades. If they were in control of the lower cost CV MIG equipment, they should not have been having MIG weld quality - productivity issues with most steels and alloy welds.

IT'S 2103: PLEASE NOTE THIS SITE HAS BEEN HERE SINCE 1997, CONSIDER IT A BLOG, A HISTORY OF WELD ISSUES AND EXAMINE HOW WELD PROCESS AND EQUIPMENT PROBLEMS OF THE PAST ARE SO OFTEN RELEVANT TODAY. ENJOY REGARDS ED CRAIG. www.weldreality.com.


As a result of more than two decades of poor performing, erratic pulsed MIG equipment, the global MIG weld industry has flushed down the drain, hundreds of millions of dollars in unnecessary weld weld equipment - weld quality and productivity costs. The costs were generated from;

[] unnecessary robot - manual weld part rejects,
[] unnecessary robot - manual weld rework,
[] unnecessary robot down time,
[] operating with lower weld deposition rates (higher labor costs) than that which could have been attained from conventional MIG spray transfer,
[] unnecessary costs for the the robot - manual pulsed MIG weld equipment,
[] unnecessary high costs for the pulsed MIG equipment repairs.



IN THE 25 YEARS OF PULSED MIG PROCESS DEVELOPMENT, I DO NOT KNOW OF ONE PULSED POWER SOURCE THAT WAS RECALLED DUE TO PULSED EQUIPMENT OR WELD ISSUES. THIS PATHETIC SITUATION IS A REFLECTION |
OF THE GENERAL MIG PROCESS MANAGEMENT APATHY THAT EXISTS IN GLOBAL WELD SHOPS?

Of course weld equipment manufacturers like ESAB, Lincoln, Miller, Hobart and Panasonic should always act in a responsible manner and recalled the pulsed MIG equipment that they knew had electronic issues. However
if their customer (weld shops) were not complaining, (they lacked the expertise to correctly evaluate MIG equipment), then why would the equipment manufacturers bother with a recall?

WELDING MOST COMMON STEEL - STAINLESS APPLICATIONS, A QUALIFIED WELD DECISION MAKER, WITH AN UNDERSTANDING OF MIG WELD PROCESS CONTROLS WOULD NOT SEEK THE ADVICE OF A SALES REP AND PURCHASE MIG EQUIPMENT THAT BRINGS NO REAL WORLD WELD QUALITY OR PRODUCTIVITY IMPROVEMENTS.

A weld reality for steel welds: The majority of the pulsed MIG equipment purchased from the early nineteen eighties to 2013, has been selected and purchased by individuals who lacked MIG weld process control expertise necessary to optimize the much lower cost. traditional, CV, MIG equipment.

Note: If you want the ultimate books and MIG and flux cored weld best practices and process control self teaching or training resources, click here.


 

2008: Engineers, managers, technicians and supervisors who for decades have a difficult time controlling the simple, two control MIG power equipment, are now talking about controlling MIG equipment with useless "wave forms".
 


 

> 2008: The electronic pulsed MIG equipment that has been developed for more than the last two decades for carbon steel and stainless welds is finally delivering a few real world weld benefits, however before you waste thousands of dollars on a pulsed MIG power source check out the following pulsed MIG information
from equipment - process evaluations from Ed Craig.


IN CONTRAST TO THE LOW COST, TRADITIONAL, DURABLE MIG EQUIPMENT THAT CAN PROVIDE OPTIMUM SHORT CIRCUIT AND SPRAY TRANSFER WELDS;

[] PULSED AND ALUMINUM MIG WELDS: Pulsed MIG provides benefits welding < 4 mm aluminum parts. When used on alum part > 4, mm, in contrast to spray transfer, pulsed MIG may produce inferior aluminum weld fusion and produce welds with more porosity.

[] PULSED AND GAGE STEELS MIG WELDS: Pulsed MIG can provide limited weld benefits for steel gage parts, (20 to 10 gage) however the weld benefits are so limited there is no justification for the purchase of the pulsed MIG equipment.

[] PULSED BETWEEN GAGE AND THE THICKER METALS: When manual welding 2 to 4 mm Carbon steels and Low Alloy steels, with these welds when used with automation and robots, the pulsed MIG process can provide slightly higher weld deposition rates that enable faster weld speeds. (be aware those speeds cannot be achieved with manual welds).

[] PULSED MANUAL STAINLESS WELDS 2 - 3mm: Welding stainless or alloys in this thickness range with short circuit and some of the welds may be sluggish. In contrast, the open arc pulsed MIG mode provides more weld energy, as does the start point of spray with an 035 wire with a 98 argon - 2 CO2 mix (an Ed Craig gas mix) that is if your welders know those low end spray settings.


Note: With food processing equipment stainless thin gage welds <0.100 in which an irregular weld surface has to be addressed, in contrast to short circuit, the pulsed process can provide slight cosmetic improvements, however these welds still typically are ground so what's the point?


Note The best weld quality on all stainless welds > 14 gage is derived from the TIP TIG process.

[] PULSED AND MANUAL STAINLESS WELDS > 3 mm..
.
On stainless applications, pulsed MIG benefits are derived from the lower open arc weld energy potential than that attained with spray,, this can reduce on some parts weld distortion. However remember when you attain one weld benefit you often loose another. The lower pulsed weld energy can also lead to lack of weld fusion and porosity.

WITH PULSED MIG, WELD FUSION HAS TO BE THE FIRST CONCERN: For optimum weld fusion and the best arc stability (important attribute with high speed welds > 30 inch/min) the traditional, lowest cost MIG weld equipment and the correct choice of wire diameters - MIG gas mixes with spray transfer, would be a more logical approach than selecting the pulsed MIG mode with it's fluctuating low to peak current..

[] PULSED MIG AND HEAT SENSITIVE ALLOYS: Welding duplex and any heat sensitive alloy applications, the best manual and automated weld process is the TIP TIG process.

[] PULSED MIG CLAD OR WELDS THAT BENEFIT FROM LOW WELD DILUTION: Welding clad and other applications that require low weld dilution. Consider TIP TIG if NDT examination of internal weld quality is required or if the mechanical - metallurgical properties are a concern. Also with TiP Tip you will likely require less weld layers to attain the corrosion properties you desire. I would consider pulsed MIG for cladding applications which have lower NDT quality and metallurgical requirements.



When manually welding most common carbon and low alloy steel applications, the purchase of costly pulsed MIG equipment, metal cored wires and three part gas mixes may provide band aid solutions but will not l not cut your weld costs or improve your weld quality. The pulsed MIG process will however add to the general MIG weld process confusion that prevails in most global weld shops.


The weld problems most weld shops have are generated from lack of weld process expertise. Rather than reaching out for bells and whistles and magic three part gas mixes, It would be much more cost effective to provide weld shop employees and decision makers with my $400 best practices and process control training program.



There is one great weld benefit attained when you purchase those bells - whistles and sales influenced welds consumables. These purchases provide increased profits for the manufacturer and suppliers of the products, and the added confusion they generate in the weld shops increases the shops reliance on their salesmen for weld advice.
.



 




2004: Auto parts and one of my pulsed MIG weld reports.

The primary issue I found with your automated, Bancroft MIG welded, stainless Torque Converter parts was the 0.053 thickness and the wide weld gaps. On MIG welded gage parts that are less than 0.075, sensitivity to weld burn with automated applications is always a major production concern, especially when welded with the spray mode. Also these "leak tested parts were not suited to short circuit as this process would provide inconsistent weld fusion. The weld fusion and burn through issue on these parts was further compounded as the lap weld variable gaps were packed with stainless mesh.
Click here for the rest of the story and the weld solutions.




If weld quality is your first criteria, remember,
Pulsed MIG and regular TIG cannot compete with TIP TIG


When asked for his opinion on MIG spray transfer logic versus pulsed
MIG, a college drop out named Albert might have said the following.


"It's logical that that the constant weld energy attainable from CV MIG spray transfer, is of course a prime attribute in attaining consistent weld fusion
and consistent weld transfer during high speed welds".




A PROCESS INVENTED BY ENGINEERS WHO DID NOT UNDERSTAND WELDS:
If you read the early 1980s research papers published on the newly developing pulsed MIG process, one of the prime justifications for the development of the pulsed process for carbon / stainless steel welds was to have a weld process suited to making weld in all positions.

1990s. Photo on right. Ed testing a pulsed MIG, STT over head weld, on a 16 inch gas pipe pipe root.


PULSED FACT: Since the pulsed MIG introduction in the nineteen eighties, when welding many steel applications vertical up and over head, the pulsed MIG process has not been able to compete with the all position gas shielded flux cored wires developed in the 1970s - 1980.

It must annoy MIG equipment manufacturers who see great profits from the sales of their useless bells and whistles MIG equipment, that the $1.80 lb, E71T-1 flux cored wires can attain superior all position weld results when used on low cost, durable, $3000, CV, MIG equipment little changed since it was developed in the 1960s.

If you want the best weld quality with all position welds, you improve the process that has always provided the best all position weld quality. That process is called TIP TIG



IT'S NOT ROCKET SCIENCE. WHEN PURCHASING MIG EQUIPMENT, WELD SHOP FOCUS HAS TO BE ON THE WELD QUALITY ATTAINED AND THE COST OF THE WELDS PRODUCED.

If before 2006, you were a frequent user of the pulsed weld process and you were welding carbon steel applications, it's likely in contrast to the traditional, CV lower cost equipment and the spray transfer weld mode, you would have been producing steel welds on parts > 4 mm with the following detriments;


[] Your pulsed MIG welds were producing Inferior weld fusion,
[] Your pulsed MIG welds were producing unnecessary weld porosity,
[] Your pulsed MIG welds, especially with automation increased arc instability,
[] Your pulsed MIG welds were made with less weld deposition rate potential.

In 2013, if you are using pulsed MIG, it's likely you are still having the above mentioned weld issues.

Of course like many managers and engineers, you may also have been using pulsed MIG equipment for the last decade and were not aware that you were overpaying for the MIG equipment bells and whistles and that this equipment was influencing both the weld quality and production. Welcome to weld reality.

When examining new MIG weld technology, one should remember that the conventional short circuit and spray transfer modes that were developed and perfected over five decades, also offer unique weld benefits. However the short circuit and spray weld benefits are rarely derived from weld personnel who have to "play around" with weld controls. To attain MIG process benefits from low cost MIG equipment requires MIG process expertise and that's a rarity in many weld shops.

 




Ed optimized both robot and manual
MIG welds for more than a 1000 companies.


A FEW OF ED'S MIG ROBOT WELD PROCESS OPTIMIZATION PROJECTS. FORD F150 FRAMES - VOLVO CABS - CORVETTE FRAMES - HARLEY FRAMES - NEW BEETLE SEATS AND ED ALSO ESTABLISHED THE ROBOT WELD FOR THE WORLD'S LARGEST CATERPILLAR TRUCKS.



Click here. Robot Weld Best Practices / Process Control materials.

 


WELD PROCESS CHOICES ARE MADE MORE DIFFICULT, ESPECIALLY
WHEN WELDS SHOPS ARE DAILY IMMERSED IN WELD PROCESS CONFUSION:


Many of you have worked or still work in weld shops in which the managers, engineers and supervisors are not aware of the real cost of that common
MIG or flux cored, 1/4 (6 mm) fillet weld.

Many of of you have worked in a weld shop in which AWS inspectors daily criticize MIG and flux cored weld quality, yet these individuals lack the weld process control expertise necessary to provide the settings that would improve the welds.

Many of you have worked in weld shops in which the majority of weld personnel daily "play around" with their MIG or flux cored weld controls?

Many of you have worked in weld shops in which the management, supervision and engineers have an umbilical cord attached to the local weld sales rep. This is the guy has an open door invitation to come in and demonstrate the latest MIG gas mix, weld consumable or power source?

Many of you will work in shops where you know the weld decision makers who selected the costly, sales driven pulsed MIG equipment or unnecessary three part gas mixes, were typically not qualified to make rational MIG weld process / equipment selection decisions.

This lack of process control expertise is common in weld shops in which the management, supervisors and engineers have minimal ownership of the weld equipment, processes and consumables utilized on their weld shop floor.





DO YOU NEED TO CHANGE WELD PROCEDURES
WHEN YOU CHANGE PULSED MIG EQUIPMENT?




12/2008: Question. Ed. We pulsed MIG weld aluminum. The weld wire most used is 4043. 3/64 and for the weld gas we use straight argon. For a few years we have been using Miller XMT - 304, CC/CV Inverters for our pulsed welds. The application comprises of aluminum parts 4 to 9 mm. As we are expanding, we are looking to purchase six new Miller 350 pulsed MIG units, approx. price $5000.

As the lead welder, I was asked to try out the Miller 350P. Frankly I was a little concerned about the criteria I should use for testing new pulsed MIG equipment. By the way I asked our CWI level 111 inspector would we have to make any changes to our pulsed AWS qualified MIG procedures if we purchased this equipment. The AWS code gives no advice about pulsed equipment changes and weld procedure data. The CWI response to the new pulsed equipment was indifference as we were changing Miller pulsed equipment for Miller pulsed equipment. Regards BA.

Answer from Ed. With the aluminum thickness range you are welding weld fusion issues and porosity problems are common and any weld inspector (most weld inspectors lack weld process control expertise) should be concerned with the introduction of new pulsed MIG equipment, irrespective of the source of that equipment. Miller will be the first to tell you there are numerous differences between each new pulsed power source the introduce.


Lets say for example you are pulsed MIG welding 6 mm, aluminum fillet welds with straight argon and setting that 3/64, 4043 wire around 400 to 450 inch/min with the Miller XMT - 304. You then set the same pulsed wire feed settings with the Miller 350P, you would be surprised to find that you will end up with a weld that has less weld energy providing less weld fusion. Your XMT power source, has a different aluminum pulsed program in which the pulsed parameters will provide higher energy welds resulting in more weld fusion than that attained with the 350P. So using your existing weld procedures would result in welds with lack of weld fusion.

Note: With aluminum, extra weld energy also produce less porosity. It's important to note the influence of the weld process - application expertise (often lacking) of the individuals who developed the pulsed programs and the sophistication of the electronics that deliver the pulsed welds. The bottom line is a 350 amp Pulsed MIG power source from two years ago may have little in common with that modified 350 amp pulsed MIG power source purchased today.

THANKS TO PULSED MIG EQUIPMENT MANUFACTURERS LACK OF INTEREST IN APPLYING GLOBAL WELD PROCESS STANDARD GUIDELINES FOR THE PULSED WELD TRANSFER MODE, CHANGING PULSED MIG POWER SOURCE MODELS SHOULD NOW BE CONSIDERED BY CODE BODIES AS AN ESSENTIAL WELD VARIABLE, THAT IS UNTIL SOME UNIFORM GLOBAL PULSED WELD PROCESS CONFORMITY IS ESTABLISHED:

Companies who are concerned with maintaining the MIG weld quality they established in their weld qualification procedures, need to be aware that when those short lived pulsed power sources break down and are replaced, with different pulsed MIG equipment, that at the end of the day, unlike the lower cost traditional CV MIG equipment, the pulsed welds produced may have little in common with the welds produced with earlier equipment utilized in producing the original weld qualification procedure.

Of course if you are welding thin gage aluminum parts < 4 mm, the differences in the pulsed equipment may not be relevant, however when dealing with code quality welds on parts > 4 mm, the weld fusion concern factor needs to kick in, and weld macros should be required to ensure the pulsed procedures from the new pulse MIG are acceptable.


AN OPTIMUM PERFORMING - COST EFFECTIVE
PULSED MIG POWER SOURCE:

What do i do when testing pulsed MIG equipment? I like to be aware of the optimum low and especially the high pulsed wire feed settings that requires high peak current. I would examine the weld deposition rate potential per application. I examine the suitability of welds produced on the common thickness used in the plant. If I am welding thin gage aluminum, I look at the fast freeze characteristics of the weld and the weld appearance. I look for the arc stability with short and long length weld cycle times.

At the end of the day. In 2013 there is still no justification for pulsed MIG equipment for welding steels. However at times when I would require a pulsed MIG unit, as this picture indicates, I have a preference for pulsed equipment which I believe has optimum pulsed weld dynamics and good pre-programmed data. I like pulsed equipment that allows me to change the primary pulsed parameters that are suited to my specific applications, (especially important for cladding and specific alloys). One reasonable priced, consistent performing pulsed power source that comes to mind, is the OTC digital pulsed MIG unit.

Note: More on the pulsed weld equipment influence in the pulsed MIG
section two and in the MIG equipment evaluation section.



Weld Process Controls should always start in the front office:

From an Ed Craig report to a General Motors plant. 2001:


When your managers and engineers recognize that Weld Best Practices and Weld Process
Controls knowledge is far more important than the purchase of costly, useless electronic weld equipment with bells and whistles, your plants will take a giant leap towards establishing optimum robot weld quality and productivity.


 





Lincoln did not "shed any light" on this
sad MIG Power Wave application:



One customer I assisted around 2005, manufactured carbon steel street lamps 11 to 7 gage. These are extensive yet simple manual weld applications. On the end of the lamps a large heavy flange is welded. The flange mounts the lamp to the floor. The flanges were 13 mm thick. There was also a weld around the pole access box, (gage material) located near the flange.

This simple street weld lamp application, became unnecessarily complex the day the company decided the parts should be welded with a robot.

The company ordered a Lincoln Fanuc ArcMate 100 robot. The robot came with the Lincoln Power Wave, 450-amp, pulsed MIG power source. The robot system was sold by AGA who had the technical support from Lincoln and Fanuc. Almost two years after the robot was installed the robot had never come close to it’s daily weld production quota. When the robot was installed, it was placed on the lamp production line, however as numerous weld issues occurred and the management moved the robot to another part of the plant so the highly trained plant personnel could “play around” with the robot weld settings.

After assistance of the so called robot weld experts from Lincoln, Fanuc and AGA, the lamp company personnel "played around" with the robot weld data for almost two years with pathetic results. For the rest of the story, click here.





Is your organization ready to stop playing with weld data and provide MIG and flux cored weld process control training?

 

I hope the following comments on Pulsed MIG and the weld process comparisons with traditional MIG short circuit, spray and the flux cored process, will provide you or your organization a different perspective on the rationalization of the purchase of pulsed MIG weld equipment and the need for process expertise.





1989. Ed was invited by the Brazilian Society of Mechanical Engineers to give a speech on welding in Rio. Ed titled the speech;

"Why Brazilian Engineers should avoid the robot weld mistakes of the North American Auto and Truck Industry".



You cannot optimize a weld process in this confused industry, unless you can separate the mistakes of the weld industries past and be aware of the weld sales hypes that influences too many weld shops.




< 2005: An interesting Weld Shop QUESTION:



Management should ask this question more frequently.

To Pulse or not to Pulse, especially if they want to
produce welds without fusion issues and cracks.

 

MILLER MAXTRON AND INVISION POWER SOURCE PROBLEMS:

E-mail. From a manufacturing manager at Hayes Lemmerz. Hayes. Ed Hayes is a global manufacturer of car and truck wheels. We use the Pulsed MIG process for most of our wheel welds. Since we introduced the Miller Maxtron and Miller Invision equipment to our automated, MIG weld production lines, we have had extensive, weld production and rework issues. The typical wheel pulsed weld problems that we experienced with the Miller equipment were;

[1] welds skipping, resulting in weld areas that contain
unacceptable and inconsistent thin welds,
[2] missed welds,
[3] welds with inconsistent weld penetration,
[4] weld globs,
[5] unexplained weld porosity,
[6] Inconsistent weld surface appearance,
[7] inconsistent weld undercut,
[8] numerous arc starts, weld crater and weld tie in issues,
[9] numerous wire burn back issues,
[10] extensive weld equipment break downs.
Please give us a call we would like to utilize your expertise.

At the request of the Hayes management, I evaluated the pulsed MIG weld issues and quickly revealed to the Hayes management the root cause of their extensive weld issues and that root cause was the Hays management, the engineers and weld equipment. For the rest of this story click here.



Welding steels? I now consider myself an old fart who has evaluted pulsed MIG for more than 25 years and s its a rare event, I will only use or recommend "manual" pulsed MIG when it delivers real world weld quality - productivity benefits and can therefore pay the bills.




FOR THOSE OF YOU THAT ARE LESS THAN 40 YEARS OF AGE AND THINK I AM AN OLD FART STUCK IN A 1970 MIG EQUIPMENT TIME WARP. MY WIFE WOULD AGREE THAT I AM OLD FART, HOWEVER I AM AN OLD FART THATS ASSISTED OVER 1000 COMPANIES WITH THERE WELD ISSUES, AND BY THE WAY THAT'S NOT MY PICTURE ON THE LEFT.

in the few years I have been in this business I have set some of the world's most sophisticated automated and robot weld applications and as the corporate weld manager with ABB, North America Robot Div, I believe I have a little knowledge about robots and their weld process requirements.

As someone who has been in so many weld shops in 13 different countries, I believe I have a good grasp of weld shop culture and weld shop management.


In 2006 I was hired as the corporate weld manager with WSI, (Aquilex) . This is a company known for it's expertise in Nuclear plant weld repairs and for cladding approx 75% of the world's power plant and waste energy water wall boilers. WSI at that time used over one million pounds of stainless and inconel weld wires on automated pulsed MIG clad welds on the water wall tubes. This ASME clad application actually attained unique weld benefits from the pulsed MIG process.



I was hired by the WSI engineering manager as he believed while his automated weld equipment had evolved past the complex water wall clad welding needs, the actual clad weld results from the pulsed MIG equipment and field weld personnel left more than a lot to be desired.

The pulsed clad weld quality left extensive lack of fusion, poor weld overlaps, extensive surface weld issues and unnecessary excess welds with the $26/lb, inconnel wires. A major issue with the power plants was the clad water wall
welds too often applied too much weld heat that had a negative impact on the boiler wall longevity.


In less than three months of pulsed MIG equipment evaluation and weld process development, I developed new pulsed MIG clad weld practices and procedures that dramatically improved the inconel - stainless weld quality and lowered the weld heat. The inconel clad welds I produced, (untouched clad weld photo above) delivered over 15 lb/hr and reduced the amount of clad water wall welds required per square foot by approx. 28%. Remember this was a company that purchased over a 1 million pounds of clad weld wire for it's water wall clad applications. For this application I required unique pulsed parameters and had to develop a unique pulsed program. These were parameters that could not be attained with the Miller, Lincoln or ESAB pulsed MIG equipment that was part of the WSI pulsed MIG equip evaluation.

The important thing with any clad application is minimize the weld dilution. In contrast, the important thing with welding is attaining consistent, optimum weld fusion. What make Pulsed MIG a poor choice for many weld applications, makes it a good choice for specific clad applications. The above clad welds would not be possible with the spray transfer mode.

I started my weld journey MIG welding tractors at Massey Ferguson, Manchester UK, in the early 1960s. I wrote my first MIG weld process control article in the late 1970s. Exited at the potential of Pulsed MIG, I wrote my first pulsed MIG article for the USA. Weld Journal in the early 1980s. During the last 3 decades I Have written four books on MIG weld best practices - process controls and had more than 30 weld process control articles published. In this time period I was also the Weld Product and Training manager for four of the world's largest weld equipment manufacturers and suppliers.

THE BOTTOM LINE, I BELIEVE I AM QUALIFIED TO HAVE AN OPINION ON WELDS.





$10.000 for erratic pulsed MIG equipment on the left.
$3000 stable CV MIG equipment used on the right.


What the weld equipment manufacturers MIG equipment may
produce, and what most welders will never see.



As the above MIG pulsed current - weld voltage graph indicates, on the left you have a highly sophisticated Panasonic pulsed MIG power source, and on the right you have a similar parameter graph with a low cost, traditional CV MIG power source.

TRANSFERRING THE PULSED MIG WELD WIRE IN WELD DROPLETS OR A WELD STREAM, WHO CARES?
Typical concerns with pulsed MIG equipment when welding steel components.

[] Pulsed Weld Fusion: A primary issue with the pulsed MIG weld fusion is this process spends 50% of it's time at a typical back ground weld current of < 100 amps.
[] Pulsed arc stability is important for weld quality. Pulsed MIG drops need to transfer without interuption. Pulsed welds are often influenced by the power source electronics which cannot deal with short arc lenths and wire stick out variations and the many weld - part (like mill scale) variables that can influence the weld transfer.
[] Pulsed MIG and vert up welds. An issue that few weld shops think about. There is a reason why TIG welds produce the best weld quality on all position pipe welds. TIG provides constant high weld energy with very low deposition rates which require very slow weld speeds. High energy and low speeds is beneficial in attaining consistent weld fusion. In contrast, pulsed MIG provides fluctuating, moderate weld energy with pipe weld deposition rates that can be 700% higher than TIG. The pulsed MIG deposition leads to much greater weld mass and faster weld speeds than TIG, this reduces weld fusion potential.
Note: The best weld process for pipe welds is revealed at www.tiptigusa.com.



FOR DECADES THE WELD INDUSTRY SUFFERED TREMENDOUS WELD COST CONSEQUENCES FROM THE ERRATIC PERFORMING PULSED MIG WELD EQUIPMENT.


2013: During the last two to three decades, most of the erratic pulsed MIG equipment required numerous
E-Prom and circuit board changes, yet as far as
I am aware, not one of the major pulsed weld equipment manufacturers ever did a pulsed MIG power source product recall.

AN INDUSTRY THAT LACKS MIG WELD PROCESS CONTROL EXPERTISE IS AN EASY CUSTOMER FOR WELD EQUIPMENT MANUFACTURERS THAT MAKE FAULTY MIG EQUIPMENT, OR MAKE WELD EQUIPMENT WITH BELLS AND WHISTLES THAT PROVIDES NO STEEL OR ALLOY STEELS WELD BENEFITS.

IN A DIRTY WELD SHOP, WELD EQUIPMENT DURABILITY USED TO MEAN SOMETHING:
Traditional CV MIG weld equipment used to last 10 to 20 years, and the weld equipment repair costs carried out by the plant's electrician was typically a few hundred dollars. Today many of the companies who have purchased pulsed MIG equipment will pay $2000 to $5000 for pulsed MIG weld equipment repairs, and these repairs are too frequently required before the weld equipment is 48 months old.


2013: Statistics that the major weld equipment manufacturers wont discuss.

[] WHAT PERCENTAGE OF PULSED MIG EQUIPMENT LASTS
BEFORE IT'S WARRANTY EXPIRED?

[] WHAT THE AVERAGE LIFE OF A PULSED POWER SOURCE IS?

[] IN A FIVE YEAR PERIOD, WHAT THE AVERAGE
REPAIR COST IS FOR THE PULSED MIG EQUIPMENT?

[] HOW MANY COMPANIES WHO USE PULSED IN ROBOT CELLS, HAVE HAD
TO PURCHASE AN ADDITIONAL PULSED POWER SOURCE SO THEY HAVE A SPARE?

[] HOW MANY HIGHLY QUALIFIED MAINTENANCE ELECTRICIANS FEEL
COMFORTABLE ATTEMPTING TO REPAIR A PULSED MIG POWER SOURCE?

[] HOW MANY COMPANIES REALLY ATTAINED REAL WORLD BENEFITS FROM
THAT NEW COSTLY PULSED POWER SOURCE?

It's a sad reality that many companies will pay $3000 to $5000 for pulsed MIG weld equipment repairs, which is more than the cost of a new CV MIG power source and wire feeder.

Remember that traditional, CV power source. It's that low cost weld power source which can provide optimum MIG - Flux Cored weld productivity and quality, that is if you provide the weld personnel with weld process control training. This is the MIG power source that should last one to two decades without repairs.

What helped the low durability, higher cost, more erratic, lower weld energy pulsed MIG process become so popular in the last two decades?


[] In contrast to producing traditional CV MIG equipment, when manufacturing pulsed MIG equipment, the power source manufactures can reduce their alloy, labor and shipping costs

[] Like the auto industry, all MIG equipment manufactures are aware that when you add electronic bells and whistles to the weld equipment you can dramatically increase the MIG weld equipment prices.


[] What motivates the weld sales rep? When you sell products with lousy gross margins your only hope is to sell weld equipment in the high dollar range and pulsed MIG equipment typically sells for 100 to 200% more than traditional MIG equipment. Also its beneficial to any sales organization that if the durability of your weld equipment is reduced, the customers will have to purchase more equipment.


 

Don't try this titanium weld (video below) with your
pulsed MIG or regular TIG. the welds will fail.


Titanium Welds: TiP TiG versus the regular TIG process.

TRADITIONAL ORBITAL TIG ON
GRADE 2 TITANIUM
MANUAL TIP TIG ON GRADE 2 TITANIUM


While using the slow manual or automated regular TIG process, there is always concern about the oxidation effects on Titanium alloys.

Typically all position, manual or mechanized titanium TIG welds on parts > 3 mm will be carried at weld speeds in the 2 to 6 inch/min range. To protect those low speed, high heat welds, trailing shields are a critical weld requirement to minimize the effects of oxidation. If trailing shields are not used, the weld shop uses extra large shielding nozzles and stops the weld frequentlty to get the part under a specific temperature.

When welds are sensitive to oxidation you know weld rework and weld porosity will be an issue. The high TIP TIG weld speeds and weld TIP TIG weld agitation will produce the highest quality, cleanest titanium welds.


With either the manual or automated TIP TIG process, TIP TIG titanium weld speeds will be much faster.

The higher TIP TIG weld speeds will typically be in the 9 to 40 inch/min range. The high TiP TiG speeds enable most titanium welds on parts > 4 mm to be complete, none stop and produce produce 100% silver color without the use of a trailing shield.

TiP TiG enables better than TIG quality at MIG travel rates. This weld was made at 24 inch/min.

If your organization uses regular TIG on Titanium, you will be pleased to know that with TIP TIG, most manual or automated titanium welds will typically be done 100 to 300% faster with superior weld quality and the lowest possible weld heat
.

visit www.tiptigusa.com.

 

AN IMPORTANT WELD COST REDUCTION MESSAGE TO ALL DEFENCE CONTRACTORS: As reported in the 2009. September. AWS. Weld Journal, the above (left frame) orbital Titanium welds were carried out on US Navy ships. On one ship approx. nine orbital TIG weld units were used to weld CP Grade 2, titanium welds. The titanium welds were required on more than 12000 feet of titanium pipe which was used on each ship.

Typical automated weld travel rates from the costly orbital weld equipment was 3 - 4 inch/min. If they had selected the TIP TIG process on the orbital units, the TIP TIG welds would have been made at minimum weld speeds of 12 to 25 inch/min producing a dramatic reduction in weld heat input, (less chance for oxidization) with no weld quality issues or costly weld rework concerns. It's also reality that with the TIP TIG weld benefits, these titanium welds could be made with the same quality and productivity with manual TIP TIG welders instead of that costly automated equipment. You don't have to be an accountant to figure out the dramatic equipment and labor cost reductions (over 2 million dollars on this one weld project) if the engineers had look forwards instead of back wards.



Any manuafacturing manager who is worth a pinch of salt, knows
that if it sounds complex, it likely should not be in a weld shop




In an industry that does not think twice about playing around with a 50 year old, two control, traditional CV, MIG power source, we have the following BS?

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< 2010. DURING THE LAST TWO PLUS DECADES OF SLOW PULSED EQUIPMENT DEVELOPMENT, (THANK GOD COMPUTERS EVOLVED AT A MUCH FASTER RATE), MOST PULSED MIG EQUIPMENT WAS PROVEN TO PROVIDE NO WELD BENEFITS FOR MANUAL MIG OR HIGH SPEED ROBOT WELDS ON CARBON / LOW ALLOY STEEL APPLICATIONS, YET THE MAJORITY OF NORTH AMERICAN WELD SHOPS COULDN'T BUY THEM FAST ENOUGH.




IS THIS THE NEXT BS YOU WANT TO SEE AND HEAR IN YOUR WELD SHOP?


The unique $12000 MIG power source called called X-MIG, is controlled by a palm pilot. This power source offers artificial intelligence with adaptive synergic controls. You know you cannot control a weld without wave forms and
X-MIG provides five million wave form variations.

With X-MIG you get fuzzy, weezy, fuzzy woozy logic and triple AC pulsed on triple DC pulsed. X-MIG also provides a refined super adaptive turbo pulse which gives
the arc an additional boost. included with
the X-MIG, is a modified short circuit mode called MSC.

Your new, X-MIG power source can also be hooked up to the welder's cell phone or I-Pod, and controlled if you feel the need with the palm pilot through the ethernet.


X-MIG comes with a two week warranty, (check small print for warranty clauses) and there is no return policy. By the way as we feel we are not responsible for the performance of this power source we feel you should be aware that it has never been field tested correctly. To order this unique, useless MIG equipment, which cost the price of a small car, contact the industry leaders in new weld technology, at askaweldsalesman.com




Could your weld shop produce a better weld than this?



Ed made the above Robot weld and the manual MIG weld below, using spatter free, MIG spray transfer from a $3,500 traditional, CV. MIG power source that had no electronics.





CV MIG Spray weld.

The low cost, durable, 400 amp, CV MIG power source
I utilized on the above spatter free spray weld, was developed four decades before Wave Forms and Fuzzy Logic became weld weld sale's buzz words.

 

THE MORE COSTLY THE PULSED MIG EQUIPMENT, THE MORE COMPLEX AND MORE EXPENSIVE THE MIG WELD EQUIPMENT REPAIRS. .WHEN THE MAINTENANCE SUPERVISOR SAW THE NEW PULSED MIG EQUIPMENT, HE REALIZED HIS ELECTRICIANS WERE SIMPLY NOT CAPABLE OF FIXING THE MIG EQUIPMENT.

THE SUPERVISOR HAD A DIFFICULT TIME FINDING A LOCAL EQUIPMENT REPAIR SHOP THAT COULD PROVIDE THE NECESSARY ELECTRONIC PULSED WELD EQUIPMENT REPAIRS WITH A QUICK TURN AROUND. TO MAINTAIN HIS DAILY ROBOT WELD PRODUCTION. HIS COSTLY SOLUTION WAS TO ORDER ANOTHER 4 PULSED MIG UNITS AS SPARES.


To purchase MIG equipment wave forms you don't need, how much will your company this year budget for new pulsed MIG equipment and the annual pulsed MIG weld equipment repairs? Two weeks after the three year old warranty has elapsed on that pulsed power source, you could end up with a pulsed MIG weld power source repair bill that is in the $2000 to $5000 range. The bottom line after that expensive repair, that three year old pulsed power source is the equivalent of a 10 year old car and you know what direction that power source is heading.


ANOTHER INDICATION OF THE LACK OF EXPERTISE AT THE MAJOR WELD EQUIPMENT MANUFACTURES: Dec. 2008. Norfolk Virginia. I requested that the local Miller rep bring in a Miller 350P pulsed power source to a client of mine for a pulsed MIG demo on Aluminum. It took 10 to 15 minutes to figure the pulsed arc characteristics were poor (insufficient energy for the moderate rate wire feed delivered) on the 5356 program welding 1/4 (6 mm) aluminum fillets. I switched the aluminum weld wire to 4043, however we could not use the equipment as the 4043 program and the arc control (voltage control) did not work. The demo failed.

 

TWO QUESTIONS YOU COULD ASK
YOUR PULSED MIG EQUIPMENT MANUFACTURER.


[1] YOU ADMIT YOUR PULSED EQUIPMENT HAS HAD MANY ELECTRONIC ISSUES, YET I CANNOT RECALL YOU INFORMING US ABOUT THOSE FAULTS OR PROVIDING COMPENSATION FOR OUR WELD ISSUES OR PROVIDING WELD EQUIPMENT RECALLS.


[2] AS WE RESENT BEING A TEST LAB FOR YOUR EVOLVING, ERRATIC WELD EQUIPMENT, WOULD IT BE POSSIBLE FOR YOU TO THOROUGHLY TEST YOUR NEXT NEW MIG EQUIPMENT WITH PERSONS WHO HAVE PROCESS / APPLICATION EXPERTISE BEFORE YOU PRESENT IT TO THIS WELD SHOP?

 

 

Arc characteristics a minor detail for some
in the welding industry .

PULSED MIG EQUIPMENT PERFORMANCE:



As this MIG volt / amp graph of a 2004 PANASONIC pulsed MIG POWER source indicates, the weld current (black) and voltage (red) are anything but stable and the volt current spikes are unnaceptable.

Arc and weld energy stability with pulsed weld equipment is something that should be a concern for any weld individual that understands the importance of attaining consistent weld energy for consistent weld transfer and consistent weld fusion.

High pulsed MIG wire feed rates can lead to excessive pulsed frequency resulting in high peak current weld content, leading to excess weld fluidity and agitated weld puddles.

 

 


Ed on right providing robot process control training for Magna plant in the USA 2004. While at Magna, he tested Lincoln pulsed Equipment versus CV equipment - spray transfer.


The following weld test comparisons were made using a Lincoln pulsed power source and a low cost MIG power source, the Lincoln CV 400. The Lincoln CV 400 costs approx. $3000.

Compare what you pay for your robot weld equipment. In 2004, the CV 400 robot MIG package, including wire feed and interface, would sell for approx. $6500. For those tier one companies who often get a twenty to thirty percent discount on the weld equipment they purchase, did you pay more than $4500 for your robot weld package, (power source and interface). Every penny you spent over this price was a penny thrown out of your window.

The Lincoln CV 400 will on the majority of weld applications outperform the much more costly Lincoln pulsed Power Wave 455 and any of the Miller, ESAB or Japanese pulsed equipment on carbon steel welds. In contrast to the low cost CV equipment, the Lincoln Power Wave unit including a wire feeder and interface will retail for around $12000 to $14000. In this segment the Lincoln CV welds are also compared with the Lincoln Invertec, an inverter pulsed power source which sells for approx. thirty percent more than the CV 400.



Using a low cost Lincoln 400: Ed made this untouched "manual", 5/16, (8 mm) fillet weld. The wire, 0.045, wire feed, 450 ipm, delivering approx. 13 lb/hr.




Note: With this untouched spray transfer fillet weld sample, no weld spatter, and the "flat" smooth weld surface. Also note the spray weld's straight edges which indicate consistent weld transfer and consistent weld fusion.


PICTURE ABOVE: With an 0.045, (1.2 mm), E70S-3 MIG wire and argon - 10% CO2 gas mix, Ed ran the 0.045 wire at a wire feed rate of 450 ipm. The 450 ipm is an optimum spray transfer wire feed rate for many auto / truck frame manufactures, robot welding carbon steel parts 3 to 6 mm. The 450 ipm wire feed rate will enable a 4 to 5 mm fillet welds at a robot travel rates of 40 to 50 ipm. This deposition rate will also produce a 1/4, (6 mm) fillet weld at a robot speed of 20 to 22 ipm
.



Pulsed MIG versus MIG Spray.
0.045 (1.2mm) wire set at 350 ipm.



Picture above. I produced the pulsed weld on left sample with the 0.045 wire. Compare it with the spray weld I made on the right using the same wire size, the same technique, the same WSO and same wire feed rate using conventional CV spray. Both welds were made with the wire feed set at 350 inch/min delivering approx. 9 - 10 lb/hr. When set at 350 inch/min the 0.045 wire is at an "optimum" pulsed wire feed setting. The 0.045 wire set at 350 ipm is also the approx. "start point" of spray transfer weld. Again note the pulsed weld inconsistency is clearly evident in the convex, irregular weld surface and inconsistent weld edges. When sectioned, you know which of these two welds provided superior weld fusion.

If you want robot weld stability at high weld deposition rates, purchase a CV power source and pay approx. $6000 rather than waste $12000 plus on pulsed MIG equipment. If you have already spent your dollars on that pulsed power source and want to improve weld fusion or arc stability switch over to spray transfer.


 

Pulsed MIG versus MIG Spray. 0.045 (1.2mm) steel wire set at 450 ipm.

Picture Above: Again you don't have to be a weld expert to see that when the 0.045 wire is set at 450 ipm, (approx. 13 lb/hr), which weld is optimum. The 0.045 wire set at 450 ipm is used on many robot spray welds on parts > 5 mm. This one picture tells you why auto industry executives and engineers have wasted millions of dollars on paying an expensive premium for electronic pulsed equipment that has not created any steel weld benefits for their plants

.

 

Pulsed MIG versus MIG Spray. 0.045 (1.2mm) steel wire set at 550 ipm.


PICTURE ABOVE: Of course if you want the maximum possible MIG weld deposition rate or highest ROBOT weld speeds from the robots on steel parts > 8 mm you will use an 0.045 wire set around 550 ipm, 15 to 16 lb /hr. This is a common spray wire feed setting you don't want to set with that costly pulsed power source. One thing you can say for the pulsed process, at low or high wire feed rates the weld inconsistency is consistent.



IT'S ALSO TRUE WITH 0.035 (1mm) WIRES.


PICTURE ABOVE: With the 0.035 wire and argon 10% - CO2. I opened the wire feed control to it's maximum setting and provided a wire feed rate of 700 ipm. Again look at the spray weld on the left versus the pulsed weld on the right. The pulsed weld with the 0.035 wire indicated the same inconsistent weld transfer pattern as with the 0.045 wire. The pulsed weld was again more irregular and convex and the side wall weld fusion was again less inconsistent than the spray weld. Again note both welds are untouched with no spatter.


In the pictures below the 0.035 wire was set at an optimum mid range pulsed wire feed rate of 550 ipm Compare with the MIG spray weld made with the same wire feed rate on the right and you can see which weld is more stable.

 


Picture Above. Again note the 0.035 wire comparison of the pulsed mode versus spray transfer weld. In the pulsed picture on the right, the welds are made at a mid range wire feed setting of 550 ipm. As the weld indicates again the traditional spray mode shows more consistency in the metal flow rate.





If you want the most effective robot and manual MIG and
flux cored weld process control training program, visit here.

Ed's process control training resources.

 


Pulsed MIG welding Torque Converters:



This costly LINCOLN POWER WAVE,
was not up to the following simple wheel weld challenge,



After years of trying to educate an apathetic big three weld management, it's only fitting that my last auto weld consulting job in the year 2000, ended up in a Detroit General Motors plant and the application was using the infamous Lincoln pulsed MIG equipment.

The GM management and engineers who typically like Ford and Chrysler engineers are not aware of the process fundamentals that weld their vehicals were not satisfied with their new multi-million dollar torque converter line pulsed MIG welds. This line had been set up to automatically pulsed MIG weld approx. 1000 torque converters daily.

The GM torque converter parts are delivered to the weld stations by conveyors. In the weld cells, the round parts rotate while the MIG welding guns are stationary. The parts required a continuous 3/16 (4.8 mm) horizontal lap seal weld. Each weld station had three MIG guns which would simultaneously weld the converters as they rotated. The pulsed MIG weld problems generated from the Lincoln equipment and a process that often does not deliver optimum weld quality delivered a product with the following;

[a] The torque converters had a 4 - 8% leak rate from the multi MIG pulsed welds. In the auto industry this leak rate in some plants would be considered good, however at this GM plant, as the weld production volume was extensive, the finished machined torque converters were very costly and weld repairs were not allowed.

[b] Excess weld heat from the multi-torch operation was also causing production "assembly" issues.

The Lincoln pused weld equipment arc weld instability at recommended pulsed wire feed settings established by Lincoln engineers and technicians caused extensive weld quality issues, weld rework and productivity issues for GM. The GM engineers had worked out the annual weld rework and loss of productivity losses for this plant would be in the range of 1.5 to 2 million dollars. For a little weld process logic from Ed who fixed the problem and never even got a thank you card from Lincoln and for the the rest of the story click here.


2004. Another Pulsed MIG Problem from Miller and I was
wondering, do those guys at Miller know what defines a good weld?
and do they ever test their pulsed MIG equipment before they release the new models?






2004: This time my pulsed MIG application was a major tier one manufacturer of stainless exhaust coupling and flexible fittings as used in the auto / truck industry. The tight tolerance, stainless parts, are rotated in an automated Bancroft welding machine with the single MIG gun stationary. The stainless MIG welds were made inside the flange. With these automated parts I was again provided the opportunity to evaluate pulsed MIG versus traditional spray.

To weld the stainless coupling parts, the manufacturer had selected Miller Invision pulsed MIG equipment and the weld transfer mode utilized was the pulsed MIG mode. The 0.045 (1.2mm) 300 series stainless weld wire was set at what should have been an an optimum, conservative pulsed wire feed rate of 300 ipm with optimum weld volts. After welding each part, the parts were leak tested. The pulsed welds looked good, yet the average weld rework as revealed by the leak test was over ten percent.

To fix the leaks, I first switched off the pulsed mode and within a few minutes established new "spray transfer" weld parameters. With the spray mode I set the 0.045 wire feed rate higher, at "400 ipm". With the higher spray wire feed rate I increased the actual weld production by 25%and the leak test for the new spray transfer welds was "zero percent".


AS THE WELD TRAVEL RATE AND WIRE STICK OUT WAS CONSTANT, THIS WAS A GREAT APPLICATION TO COMPARE THE MILLER PULSED MODE WITH SPRAY TRANSFER. To reevaluate the pulsed mode at the same wire feed rate set with the the spray weld, I then reset the Miller Invision power source back to the pulsed mode and set the pulsed wire feed rate at 400 ipm. I then fine tuned the pulsed parameters to minimize spatter with the shortest optimum arc length. The new pulsed welds looked as good as the spray welds, however when the parts were leak tested approx. 8% of the pulsed MIG welds required weld rework. I turned the pulsed mode off and from 2005 and these important auto / truck part welds are made the old fashioned Ed Craig way, using "spray transfer".

WITH PULSED MIG, IT'S OFTEN WHAT YOU DON'T SEE WITH THE WELD THAT SHOULD BE A CONCERN.

For those of you struggling with consistent pulsed MIG quality welds, be aware that in most instances the traditional spray transfer arc on parts > 3 mm can provide superior weld fusion and be more stable.

 

As much as weld equipment companies benefit from making their weld equipment complex and costly, please note MIG welding has never been rocket science. The wires in your $10 Chinese toaster provide the correct amount of resistance and current to maintain the wire in a consistent red heat condition.

As the photo on the right indicates, for a few hundred dollars, you can put two car batteries together. With the 24 volts hooked up a small spool wire feeder gun you can then produce an excellent MIG weld.

In the simple task of melting the tip of a small diameter, MIG wire, weld equipment manufactures today don't blink as they offer a sophisticated, electronic pulsed MIG power source at the cost of a small car. If you have more money than sense you know you need pulsed MIG equipment for you steel welds.












Miller Pulsed MIG Update 2008. It's the same stainless coupling company I visited in 2004, only this time we compare the Miller Axcess pulsed mode against lower cost CV equipment and the traditional spray transfer mode.

In 2004 when this auto parts supplier had problem with the Miller Invision pulsed MIG flange welds on the stainless couplings, I found that we could get the consistent weld results the company desired by switching the pulsed mode off and welding the the flange stainless welds with spray transfer. (See above story).

In 2008 Miller delivered it's new Miller Axcess with a promise that the pulsed mode was now stable and would achieve the desired weld quality on the automated stainless coupling welds. The coupling company was dubious about Miller's promises so they invited me back to compare the Miller Axcess pulsed mode against the traditional spray mode I had previously established
.

The automated pulsed MIG weld cells had a two torch setup. I set one gun on the Miller Invision in the traditional spray mode. I set the other gun to a new Miller Axcess and utilized the Accu Pulse mode. I ran both systems using the shielding gas I developed for this weld, Argon - 5 CO2. We used an 0.045 (1.2mm) stainless weld wire. The wire feed range tested was 300 to 500 ipm.


In the weld tests the Miller Axcess performed well in the pulsed mode. With both the pulsed arc and spray arc lengths finely tuned to minimize spatter. The weld results were again interesting. The Axcess package is priced about 50% more than a standard CV Miller Delta Weld package, however the Miller Axcess pulsed mode did no better than the regular MIG spray mode. It's true that the average weld current from the pulsed mode was less, however lower current on this application which was subject to leak tests was not a benefit. As for weld spatter, the coupling weld position and small ID create an excellent weld spatter trap, so weld spatter was a major concern. Again the Axcess did well on the spatter count, however the spatter results between the pulsed mode and spray mode were so miniscule that when the pulsed and spray parts were placed side to side, no one could tell which was the spray weld and which was the pulsed weld. The important bottom line for this company was there was no justification to pay the extra price for the Miller Axcess. In the afternoon I fine tuned the traditional spray mode and the afternoon shift ran 800 parts that required no weld cleaning and no weld rework.

IT'S LOGICAL FOR ANY WELD SHOP TO ASK, WHAT REAL WORLD WELD BENEFITS ARE DERIVED FROM MAKING THE MIG WELD EQUIPMENT MORE COSTLY AND COMPLEX?

WHAT DOES THE PULSED MIG EQUIPMENT HAVE TO DO TO MAKE THAT COMMON 1/4 (6 mm) FILLET WELD? As the pulsed MIG weld wire travels into the weld at typical speeds of 100 to 700 ipm, that highly sensitive, artificial intelligent pulsed MIG power source has to;

[a] Control and diagnose both the pulsed arc start and arc end weld parameters. If the preset pulsed data does not produce the weld start or the weld end crater will your weld personnel know how to set the correct pulsed data?

[b] Control and diagnose the pulsed low back ground current. If the weld is unstable or lacks weld energy, does your weld decision maker know what the optimum pulsed back ground current should be, or what an adjustment to the back ground current will do to the arc or weld?

[c] Control and diagnose the pulsed high peak weld current. Does your weld decision maker know what the optimum pulsed peak would be, or what an adjustment to the peak current will do to the arc or welds?

[d] Control and diagnose the pulsed frequency. Does your weld decision maker know what the optimum pulsed frequency should be, or what an adjustment to the pulsed frequency will do to the welds?

[e] Control and diagnose the pulsed pulsed up-slope / down slope and the pulsed profile. Does your weld decision maker know what an adjustment to the pulsed profile, (select one of 4 million available wave forms) will do to the welds?

FOR DECADES SPRAY TRANSFER HAS BEEN A SIMPLE PROCESS, YET FEW WELD SHOPS PROVIDED THE PROCESS TRAINING NECESSARY TO ATTAIN PROCESS OPTIMIZATION.. IN CONTRAST TO THE COMPLEXITIES ASSOCIATED WITH PULSED MIG, LOOK HOW SIMPLE IT IS TO MAKE THAT COMMON STEEL FILLET WELD FOR ANY STEEL OR STAINLESS APPLICATION, USING A CV POWER SOURCE, AN ARGON CO2 MIX AND 0.045 (1.2 mm) WIRE:

[1] You select one of three optimum wire feed positions, (from my weld books and training resources).

[2] You set the optimum spray weld voltage, one of two settings (from my weld books and training resources) then fine tune the voltage by the sound or spatter length and shape
.

 

If the weld shop was confused about
the two control short circuit and spray modes.

what hope does the shop have understanding pulsed
MIG if pulsed parameter adjustments are required?

 


A traditional CV, MIG power source may be short on electronics, however it does a great job while welding as it automatically maintains the arc length during wire stick out variations.

The low cost, durable MIG equipment provides three unique MIG weld transfer modes suited to all metals. Short circuit provides controlled low heat input suited from 20 gage to 0.100. Controlled globular produces a small amount of weld spatter and suited to weld 14 gage to 0.125 and depending of the use of robot or manual welding, spray is suited to welding all steel parts >0.070.

 

WHAT ABOUT THOSE INVERTERS OR CC/CV MULTI-PROCESS POWER SOURCES?.....Did you know the regular lowest cost CV power source is superior to an Inverter and a multi-process or pulsed power source when used for the MIG weld modes, short circuit or spray and for welding with the gas shielded flux cored wires?. (This info is not available from Miller, ESAB or Lincoln, however the evidence is available in my MIG and flux cored Process Control training CDs.

There is a great value for any weld decision maker, when they combine weld process expertise with a $2000 - $3000 CV power source and a simple two part gas mix that can handle the vast majority of the world's welding applications.




Ed providing MIG and flux cored process control training
to 60 engineers and managers from 6 countries.


2010: MIG WELD BEST PRACTICES AND PROCESS CONTROL TRAINING FOR WELD OPTIMIZATION. MOST COMMUNITY COLLEGES DON'T PROVIDE IT, UNIVERSITIES THAT OFFER WELD ENGINEER DEGREES DON'T DO IT, COMMUNITY COLLEGES THAT TEACH WELDING RARELY DO IT, AND WELD SHOPS GIVE IT MINIMAL CONSIDERATION .

IF THE WELD PROCESS CONTROL TRAINING IS PROVIDED FROM MY CD, MIG AND FCAW POWER POINT PROGRAMS, THE WELD RESULTS FOR YOUR ORGANIZATION CAN BE REMARKABLE.

[a] WELD PERSONNEL WILL NO LONGER HAVE TO "PLAY AROUND WITH WELD CONTROLS" TO ATTAIN OPTIMUM WELD DATA.

[b] WELD PERSONNEL WILL KNOW WHEN TO SWITCH FROM SHORT CIRC, GLOBULAR SPRAY OR PULSED OR WHEN TO CHANGE THAT WELD WIRE SIZE OR GAS MIX FOR OPTIMUM WELD QUALITY AND PRODUCTIVITY.

[c] WELD PERSONNEL WILL IMMEDIATELY UNDERSTAND THE ROOT CAUSE OF THEIR WELD ISSUES AND WILL PROVIDE INSTANT WELD PROCESS RESOLUTIONS NECESSARY FOR THE COMMON ALL WELD ISSUES.

[d] WELD PERSONNEL WILL UNDERSTAND THE RELATIONSHIP BETWEEN WELD COSTS, WIRE FEED SETTINGS AND THE WELD DEPOSITION RATES THEY DAILY ATTAIN.


A FEW OF ED'S WELD PROCESS OPTIMIZATION PROJECTS,

FORD F 150 FRAMES - VOLVO CABS - CORVETTE FRAMES- HARLEY FRAMES - NEW BEETLE SEATS AND ED ALSO ESTABLISHED THE ROBOT WELDS FOR THE WORLD'S LARGEST CATERPILLAR TRUCK.




click here for Ed's best practices / process control materials.




ARE YOUR PEOPLE WELD
PROCESS QUALIFIED?



Why not give the personell who make weld decisions this
FUNDAMENTAL MIG WELD PROCESS CONTROL TEST


HOW FAR IN THE WELDING INDUSTRY DID WE EVOLVE BETWEEN 1988 AND 2008? In the graphs below we have two MIG welds both set with optimum weld data. If you believe in the importance of MIG arc stability take your choice. Compare the spray voltage (red) and current (black) graph on right from a regular $2000 MIG power source built in 1988, with the optimum pulsed mode graph on the left from a $12.000 USA manufactured pulsed power source built in 2008.



Even lawyers could figure this weld equipment performance graph out.

 


In one weld process control presentation I provided a process control work shop with a large group of ASTEC / Kolberg managers and engineers. There was two lawyers present, ready to give a talk on patents. I asked the lawyers which of these graphs they would accept in the attainment of consistent, optimum MIG weld quality. You know they both picked the one on the right.


 

The next two pictures are are two 3/16 (4.8 mm) fillet welds I made during 2003 on 1/4 stainless steel. The welds were made with a Lincoln 300 Power MIG. The 300 power source was a single phase, pulsed MIG unit that retailed at that time for approx. $3,700. This pulsed MIG power source has pre-scheduled pulsed programs for specific wire types and diameters.

This Lincoln pulsed MIG power source was purchased by a company that welds both steel and stainless parts. Due to it's daily welding issues, (most caused by lack of process expertise) this company believed it needed Lincoln's so called unique pulsed power source. The MIG wires used for the 3/16 fillet welds were 0.035, (1mm) - 308L and 309 wires.

With the Lincoln power source, I set the 0.035 wire feed at 550 ipm, a setting that should have been an optimum pulsed wire feed rate. The power source provided the pulsed parameters, I simply had to set the trim, (fine tune the weld voltage) to attain the optimum pulsed arc length. The manual welds were untouched after welding. Take note of the mediocre pulsed weld appearance and also the heat affected zone in contrast to the spray photo.



Th following pulsed MIG picture is worth a thousand words. Provide a macro
examination of your pulsed MIG weld fusion and then compare with spray transfer.



$3700: Lincoln 300. Pulsed MIG "On".


Lincoln 300: Same wire feed settings as above
with the pulsed mode turned "off".



With the pulsed mode switched off, the Lincoln 300 power source was set to spray transfer. The same weld wire and wire feed rate as the pulsed weld were used for the 3/16 stainless spray transfer fillet weld. As you can see above, even the spray weld was poor with an obvious lack of weld energy. Poor slope output for spray is common from pulsed MIG equipment. As you can see when comparing both welds even the HAZ is similar. My point is simple. Why pay extra for the pulsed electronics when you don't need them? Why pay for something that provides inferior performance to traditional CV equipment and is less durable and more costly to repair?



Check the weld similarity from the two weld transfer modes.
Check out the Lincoln poor performance for both the pulsed and spray weld.


The above welds would be dramatically improved using the same wire feed settings and spray transfer from a regular > 250 amp CV power source. So we have another weld shop that purchased a pulsed product that did not live up to the salesman promises.

 

IF YOU WANT TO FIND THE WORLDS WORST WELDS
PAY A VISIT TO AN AUTO / TRUCK PLANT

NO WELD EQUIPMENT ISSUES HERE,
JUST LACK OF ROBOT WELD PROCESS EXPERTISE.

 

The following pictures are robot pulsed MIG welds made between 2003 and 2005 on Ford truck frames. The sad looking welds were made with one of the most expensive, American manufactured, pulsed power source available, the "Lincoln Power Wave".

I have been in too many auto / truck frame plants and from a weld perspective it was always a gut wrenching, frustrating experience. I often think the coating they put on the frames after welding is not there to prevent rust, it's there to either hold the steel together or to make sure no one can see the welds. The pathetic Ford truck welds shown below are of course not the fault of the workers on the floor and not the fault of the robots or weld equipment.

 

2003 - 2004. Weld Equipment. Lincoln Pulsed Power Wave purchased by managers
and engineers who lacked the ability to take ownership of a aimple welding process.

These Ford truck robot MIG welds were managed and programmed by engineers with degrees and robot weld personnel who thanks to their inexperienced management were not given the training required to establish Best MIG Weld Practices and Robot Weld Process Controls.



Purchase the most expensive and most sophisticated electronic
MIG equipment available. Make some bad choices on the weld wire size selected. Mix in inexperienced, hands off weld management. Toss in some poorly trained engineers, supervisors and technicians and you to will have the right combination to produce truck frame welds that look like they fell out of the rear end of a pigeon as it flew over the parts.


What a combination, America's most expensive pulsed power source welding on America's most expensive truck, it was a lousy marriage. Here in the USA we can blame the loss of many jobs on overseas lower labor costs or superior Japanese quality, which from a weld perspective is simply a myth. If we face weld reality, we may want blame a good portion of the demise of the Big Three and North American job losses on under qualified, manufacturing management who for decades lacked the ability to control and optimize the equipment they own and therfore lacked the abilty to recognize the process control training necessary for their plant employees.

 

Remember optimum MIG welds with the best possible weld fusion are not about a unique weld transfer mode such as pulsed, and so called unique wave forms, they are about a balance between the stable weld energy (slope output) delivered and the weld deposition rates and travel speeds provided.

 



Visit Ed's Weld Process Control Training Resources.




THE FOLLOWING IS A CASE OF WELD PRODUCT MARKETING / SALESMANSHIP AND BOVINE FECAL MATTER THAT FROM MY PERSPECTIVE IN HAS REACHED AN ALL TIME LOW.

I was amazed to read one advertisement in the Nov. 2003. Weld Journal, a magazine that often struggles to walk a line between it's source of advertising revenue and maintaining unbiased weld technology credibility.

The advertisement in the Weld Journal was from National Standard, (NS), a primary North American MIG wire manufacturer. The NS advert made ridiculous claims for it's new Pulse PLUS Steel MIG Weld Wire.

National Standard claimed. "That with their unique MIG wire and the pulsed MIG process you will get less weld spatter, less weld fumes and their MIG wire will reduce the need for grinding. NS also claimed that their pulsed wire is supposed to provide a wider operating range than competitive MIG wires. NS made four claims that were simply four lies.





BS from NS with it's so called Pulsed MIG Plus MIG Wire.



When an industry MIG wire leader like National Standard has to rely on marketing BS you know there will always be a salesman ready to deliver it. A sad point also is the Weld Journal printed the above add.




I guess that $12000 pulsed power source you just purchased from Lincoln that's loaded down with sophisticated electronics that controls the pulsed weld transfer, will now with the magic NS wire provide an enhanced pulsed transfer.

This type of weld product advertising belongs on the very top of the the mountain of the never ending Bovine Fecal matter that for decades has spewed from the marketing department many global weld equipment and consumable manufacturers. This is the type of weld BS data that adds to weld shop myths and weld shop confusion. This is part of the the BS that has helped destroy the technical credibility of today's welding industry.

SHAME on National Standard, a major North American weld wire manufacturer for it's gross product lies and complete lack of respect for the intelligence of it's North American welding customers.

SHAME on a Welding Journal affiliated with the none profit American Weld Society for providing this ad. This is a journal that prides itself on it's technical articles, perhaps this journal forgot that it only benefits it's "paid subscribers" as long as the information and advertising it provides is credible.

SHAME ON the welding industry that's been using the MIG process for more than five decades, an industry which still has many gullible readers that actually believed the NS claims and purchased this ridiculous MIG wire.

This NS MIG weld wire fiasco, is yet another reason why it's important that the global weld industry needs to take ownership of it's processes and why weld decision makers need to cut the umbilical cord that has been attached to weld equipment and consumable manufacturers for more than fifty years.



< 2005. When it comes to reading advertisements and welding literature written by personnel who work for world's leading MIG equipment and consumable manufacturers, before you believe what you read, put that weld shield in place, check the wire feed rates you can deliver, examine the arc and weld consistency, THEN CUT THE WELDS AND
BELIEVE IN THE WELD FUSION YOU SEE.

Ed Craig 2005.




E- Mail Weld Question
June 19, 2003.

Subject: GMAW-P Problems.

Hello Ed. We are trying to utilize GMAW-P on an HY-80 steel pipe welds. I was pushing for gas shielded flux cored wires, but our engineers will not allow flux cored wires for our procedures. The engineers complain of poor mechanical properties from the flux cored wires on the HY metal. We can't use spray as many of the welds are out of position. We are having a difficult time passing UT with our Miller Invision pulsed power source. The MIG pulsed parameters required provide a wide arc zone and long arc length, this results in inconsistent weld fusion.

We are thinking about switching to Lincoln Pulsed equipment, as they tell us with their equipment that we can control the pulsed wave forms and get better results. The Miller Equipment does not allow wave form manipulation from the interface, you have to run off the factory resets. Do you have any suggestions on getting better results with our GMAW-P equipment?


Ed's Reply: Forget that nonsense about "pulling a magic wave form out of that red machine". Your question brings to light some of the pulsed process issues I have been talking about for more than a decade. Pulsed variable parameters and pulsed arc length sensitivity combined with a lower energy, fluctuating pulsed MIG arc plasma will have welding consequences especially to those who are concerned about the weld fusion attained. Of course to attain more weld energy with pulse one can always increase the pulse parameters. However there are limits and when those parameters are outside the optimum pulsed parameter range, you will not likely be pleased with the resulting welds.

Good luck with the Lincoln Power Wave and it's numerous wave forms. I think you will find that wave form control which sounds great in the Lincoln marketing brochure is going to have have little impact on your weld applications. You may want to read one of my many experiences with the Lincoln Power Wave when it created serious weld quality issues for American Axle, a major tier one axle manufacturer. Check out the MIG equipment section.


Your statement on the engineers comments on unacceptable gas shielded flux cored weld mechanical properties shows a real problem in your organization and a common major problem for many companies.

If your company is interested in attaining consistent weld fusion and higher than traditional weld strength it should fire the engineers who made the ridiculous flux cored statement and quickly get used to welding with the highly cost effective gas shielded flux cored consumables or better still take a look at TIP TIG.

Your companies weld issues are typical of many companies in the pipe and pressure vessel industries, companies where you will find many engineers who provide MIG and flux cored weld opinions, yet few are qualified to make a rational MIG or flux cored weld process decision.

E Mail 01/ 2005.

Question: Ed I just recently purchased the Lincoln Power wave 355 Pulse power sources to weld 0.055 stainless steel pipe to a much thicker 6 mm solid donut shaped carbon steel part. These are automated welds and the nozzle to work distance is fixed. I have been experiencing arc stability issues and INCONSISTENT weld appearance every now and then during the circumferential welds. Could I talk with you in more detail regarding this problem?

Sincerely. Travis Schifferns.

Ed's answer. You are finding the weld reality that the pulsed equipment you purchased does not live up to the promises made by the equipment mfg. Call me reference the solution to this problem. Ed.



ROBOTS AND HIGH SPEED PULSED MIG WELD CONCERNS: The pulsed, inconsistent, lower open arc energy attained from < 2005 pulsed equipment was not the logical choice for many high weld speed robot applications, especially when you consider the two prime weld quality issues on many robot welds on steel or stainless parts > 4mm was;

[1] marginal or lack of side wall weld fusion.
[2] inconsistent or skipped welds caused by inconsistent transfer of the electrons across the arc.


SPRAY VERSUS PULSED PLASMA AND THE WELD STREAM:
In contrast to the ever changing, peak to back ground pulsed MIG transfer mode, the constant energy, higher velocity, denser plasma with the spray transfer weld stream, offers three unique weld attributes;

[1] Spray Transfer: With consistent weld parameters, spray transfer will provide a less fluctuating, more consistent plasma shape and therefore maintain the location of the arc plasma energy influencing the weld fusion potential. In contrast to spray, the pulsed plasma is typically weaker as 50% of it's time its at the back ground current setting. In the pulsed back ground to peak condition, the plasma profile continuously collapses between a narrow and wider plasma.

[2] Spray transfer can weld with a much shorter arc length than pulsed. The shorter arc length focuses the most concentrated area of the arc plasma plasma energy in the weld rather than over the external weld surface. The concentrated, higher energy spray plasma is beneficial to attaining optimum weld fusion and stable electron transfer with high speed welds.

[3] The traditional spray transfer plasma configuration and short arc length potential can provide an arc less sensitive to mill scale or specific coatings.


THE WONDER OF THE REGULAR MIG ARC: When you read anout the pulsed MIG electronics performing miracles as the MIG arc lengths change, remember In most robot and automated welding systems, the MIG arc length (wire tip to work distance) variations that take place during the welds should be minuscule. However if the constant voltage (CV) arc length does change during the weld, the traditional CV MIG power source has always had that unique slope feature in which a small voltage change in the arc will result in a high rapid weld current change that instantly "self corrects the arc length".


E-mail from l. KD - P&F. 12 /07

Ed, you would be interested to know that by the end of the year I will have at least 100 of our robots welding with US 0.035 (1 mm) wire using conventional spray transfer with "no pulsing". It took 10 years Ed, but we are finally using the recommendations you made to us in the nineteen nineties. I now have the top guy in North America convinced traditional spray is the way to go with the robot MIG applications. In regards to your MIG process control training programs and resources we now have two other plants that will be contacting you.

Note from Ed: This is one of the largest tier one suppliers to Honda and Toyota in the USA. The plant has hundreds of Panasonic robots and Panasonic pulsed MIG equipment.

The Panasonic weld equipment and pulsed process was a requirement of the Japanese parent company. For more than a decade, this pulsed MIG equipment which should never have ben sent to the USA, daily generated numerous weld and production issues that dramatically impacted the daily robot weld quality and production. With all the problems, the blinkered corporate engineers and apathetic, inexperienced managers in Japan were reluctant to hear that the the traditional, more durable, lower cost, North American CV MIG equipment and logical Swedish robots would provide solutions to the majority of their daily robot weld issues.

Many Japanese companies are hobbled daily with their Achilles approach to manufacturing. What is that Achilles heel? It's an arrogance that what they do is superior to anyone else. Bringing erratic performing Japanese weld equipment and Japanese MIG wires to America was like sending second grade coal to Newcastle, UK. The costly Asian weld wires provided no benefits, the Panasonic weld equipment was a disaster of inconsistency and erratic performance of the Panasonic Japanese robots left a lot to be desired.

Thanks to the Japanese general lack of MIG weld process expertise, their lack of flexibility to make changes when change was required and there disregard of the process advice I provided them 10 years previously, I believe this company has wasted at least 20 million dollars in robot down time, rejects and rework. But I suppose the important thing is the Japanese engineering egos are still intact.



Dont forget the influence of the spray weld gas
ON THE STABiITY OF SPRAY TRANSFER WELDS.

 

Click here for Ed's MIG Gas Mixes






GAS MIXES CAN PROVIDE A GREAT CONTRIBUTION TO WELD STABILITY & WELD ENERGY

In a time of equipment electronic bells and whistles, please remember with MIG gas mixes, that the CO2 gas dissociation and oxidation properties, are often not given the credit or consideration they deserve. Ed introduced 4 important gas mixes in North America and recommends you visit the MIG gas section of this site.






The Japanese will often add electronics to MIG welding equipment
without understanding why they added the electronics

 


 

E-mail. Oct 2008:

I am emailing you because I have come to a questionable snag with my pulsed MIG equipment. I have the equipment set in the spray mode. I am welding on 5/16” carbon steel material, my settings are set to spray transfer (29 volts 500 wire speed in/min).

When making a 3/16” fillet weld with the 0.035 wire I have noticed that at the end of the weld, the weld flattens out and has what I have been taught to refer to as a “fish eye” ( I am not sure if this is the right term for this problem ).

The attached photo will show you what I am referring to. When coming to the end of my weld I back over the weld about ¼” instead of just stopping. I don’t pull my nozzle away before I let the trigger go, so I don’t think this issue is caused due to the length of the stick out. My gas is set to 35cfh argon/CO2 mix.

Could you please advise what may be causing this poor finish is this just cosmetic or an issue that needs to be addressed? If this is an issue that needs to be addressed could you please explain the proper procedure for fixing. These parts are under extreme vibrations and some stresses Vertical / Horizontal and Lateral. Thank you.T Eason.

Ed's Reply. Two things going on here.
[1] First the weld picture indicates poor side wall fusion. As you are using good spray parameters the lack of fusion is likely a result that the weld surface was wire brushed, however the mill scale has been left. If you are concerned about fatique properties you don't MIG weld over mill scale. Grind the weld area before welding, I am sure you will see a difference in the weld appearence.

[2] A fish eye is typically a pore evident in a failed weld and the bright shiny appearence in the pore indicates the presence of hydrogen, so you dont have a fish eye. You do have a pulsed power source that has a built in defect. This is a a commom classic issue with pulsed equipment in which the machine controlled end parameters or burn back parameters are set too high, (more evidence that pulsed equipment manufactures don't correctly test the equipment they build.) I see this defect all the time in pulsed equipment in robot cells. At the end of the weld, the high voltage spike applied for the burn back causes a suck back effect in the arc leaving that classic hole in the crater. In many instances if you examine with magnification you will find shrinkage cracks around that hole and with your fatigue concerns, this defect has to be ground out and the crater filled in. My MIG process control training resources deal with this issue and provide process solutions, however you would be well served to send the power source back to the company who manufactured it. It's ironic that this defect would not occur on a lower cost traditional CV power source.




THE PULSED MIG PROCESS HAS MORE THAN ONE ACHILLES HEEL: Even with the world's best pulsed equipment, on many common applications the Pulsed MIG process will always have its Achilles Heel. Visit section 2 of pulsed MIG. Find out about useless wave form options and concerns for lack of weld fusion.

Invest in your weld career, its your choice talk to a salesman or order Ed's books and MIG and flux cored, manual or robot weld process control CD training resources.



IF WELD QUALITY IS YOUR FIRST CRITERIA,
PULSED MIG WILL NEVER COMPETE WITH TIP TIG


 


If you are teaching your self, or providing weld process control training for others, the following resources are the key to attaining MIG and flux cored weld process optimization.

Item.1. The Book: "A Management & Engineers Guide To MIG Weld Quality, Productivity & Costs"

Item 2. A unique robot MIG training or self teaching resource.
"Optimum Robot MIG Welds from Weld Process Controls".

Item 3. A unique MIG training or self teaching resource.
" Manual MIG Weld Process Optimization from Weld Process Controls".

Item. 4. A unique flux cored training or self teaching resource.
"Optimum Manual and Automated Flux Cored Plate and Pipe welds.

Item 5a."Proceso de Soldadura MIG Manual" (MIG Made Simple. Self teaching in Spanish)

Item 6a. The Self Teaching MIG Book/ Video. (MIG Made Simple in English).

Note: Items 2-3-4 are the most comprehensive process control, self teaching and training
programs ever developed..

Visit Ed's MIG / flux cored process control books and CD training resources.






Pulsed Section 2.

[] Take a look at the Panasonic Ripple Farce.

[] This tractor mfg paid extra when they took their advice from a weld salesman.

[] The Miller pulsed MIG equipment fiasco.

[] Lincoln Power Wave caused Ford Truck axle cracks,

[] Was this Airco MIG equipment junk?.

Continue with extensive pulsed MIG welding data your MIG
equipment manufacturer forgot to tell you, Section 2.






For MIG and Flux Cored process expertise visit www.weldreality.com