flux_cored_pipe_welding.htm

Welcome to
Flux Cored / MIG.
Structural and Pipe Weld Data.

Gas Shielded Flux Cored

Is this your pipe Shop?

WELCOME TO THE BIRTH PLACE OF FLUX CORED
AND MIG, WELD PROCESS MYTHS:

SLOW PROCESS EVOLUTION:
Its amazing in 2007, that 30 plus years after the introduction of gas shielded flux cored wires, the number of global weld shops and construction projects that still insist on using GTAW or stick (SMAW) electrodes instead of attaining the extensive weld quality and productivity benefits from the gas shielded flux cored or MIG process. The evolution of the flux cored process has been painfully slow especially in industries where unqualified weld management and mechanical or electrical engineers lack process confidence and still daily influence the weld process decisions.



PROCESS IGNORANCE: E-mail Question: Sept. 2007:
Hi Ed, my AWS approved QC guy at one of our shops had an application using 316 stainless flux cored wires. They had not used this wire before so he had to perform a weld qualification test and qualify the welders. The weld QC ran the procedure with the 316 flux cored wire and a helium
tri mix containing 90% He / 7.5% Ar / 2.5%CO2 . The welds on the header look cold, have leaks and slag inclusions etc. He told me that he got the gas info from AWS and they said the tri mix could be used for this. I think he's made a mistake. I have never heard or seen where the tri mix can be used for FCAW. Do you know if the welds can pass mechanical test requirements with tri mix.

Ed's Answer: Its hard to believe that 30 years after the introduction of steel and stainless flux cored wires, weld consumables by the way that have only ever used two shielding gases, argon CO2 and CO2, that someone who received training from the AWS and has a responsible role in a weld shop would try to qualify stainless flux cored welds with the helium tri mix.

With the highly inert tri- gas mix, you will have extensive lack of weld fusion, extensive porosity and slag entrapment, you will also possibly have welds that have exceeded their maximum strength and lost some ductility. I don't believe anyone at the AWS gave him weld advice as giving practical weld advice is not a common AWS function. A guy like this is hired for his AWS qualification and his role in this costly endeavor does not say much for the value of AWS certification.

 

 

 

There is always a place for SMAW welding, but from a weld quality and productivity and cost perspective, it should always be a limited place.

IF YOU HAVE NO SENSE OF HUMOR YOU SHOULD
NOT BE AT THIS SITE OR IN THE WELDING INDUSTRY

ED'S PIPE WELDING ROBOT:

WITHOUT QUESTION, A SIX AXIS ROBOT COULD BE ONE
OF THE MOST VERSATILE TOOLS USED FOR
AUTOMATED PIPE LINE WELDING.



.

In 1997 I set the weld data with an ABB robot to weld this 48 inch steel pipe. I used short circuit transfer for the vertical down root. The robot pipe fill pass welds were made in the vertical up position using an 0.052 Alloy Rod Dual Shield E71T-1 wire with 80% Argon - 20% C02. The robot flux cored pipe weld deposition rate was "ten pounds an hour"

The high flux cored weld deposition rate, combined with the fast robot movement between welds, (faster than any other available automated pipe weld equipment) provides greater pipe line weld production potential than any other available automated pipe weld unit.

In 2007 there is still no automated, mechanized pipe line weld unit available that can offer the flexibility or weld process communication of a six axis robot for welding pipe bevels. A robot provides many unique features for pipe welds.

[a] accurate, flexible through the arc weld joint tracking,
[b] adaptive controls that can compensate for different welding conditions,
[c] super fast speeds between welds,
[d] superior communication with the welding power source. Combined these features offer the world's greatest automated pipe welder.

Just imagine, one day we may then see two small robots hanging down, mounted on a "ROBO RIG" truck, that traverses that Texas, Canadian pipe or Middle East pipe line.

 

 

ED'S 1997 "ROBO RIG", PATIENTLY WAITING
FOR A SLEEPY INDUSTRY TO RECOGNIZE OPPORTUNITY:

 

ED'S 1997 SHOP OR FIELD ROBO RIG: Two automated pipe welding carriages welding with MIG and flux cored wires, attached to two sophisticated electronic power sources can cost over $130,000 Two robots attached to two power sources could cost approx. $100,000. The pipe welding robots could be mounted on a portable tractor driven gantry for field pipe applications.

[] Robo Rig: With two pipe welding robots hanging upside down, you have a mechanized unit that offers automatic touch joint sensing, through the arc impedance joint tracking, adaptive weld controls that will compensate for pipe joint deviations. For the pipe shop, simply present the pipe to the gantry and tell the robot the required weld schedule to use. For that pipe line, drive the Robo Rig over the weld joint. In less than 10 seconds the robots or robot will locate the pipe bevel and pipe root. Setting track for two less flexible, two axis mechanized carriages can easily take 20 to 30 minutes.

[] The Robot Rig will dramatically reduce the total pipe weld time. At the end of a fill pass weld, a robot can be in place to weld the next fill pass within 3 seconds.

[] The Robo Rig will have a flexibility that far surpass any automated pipe welding carriage. This flexibility will optimize the robot weld gun positions for the all position pipe welds. The robot can automatically sense a weld direction or side wall dimension change and instantly provide weld speed, weld direction and process changes to compensate.

[] The robot can change tools in seconds, one minute it's welding the next minute it's cleaning the slag from the welds.

[] The Robo Rig will have far superior communication and will store as many weld schedules as you will ever require.

 

 

 

IT'S GREAT TO SEE OUTSTANDING
PIPE WELD EQUIPMENT

 

INSTEAD OF THE ROBO MIG FROM ED, WE HAVE THE GERMAN VIETZ LASER PIPE RIG:

While some companies think that using STT or RMD MIG and the flux cored process on pipe welds is progressive, Vietz is developing a new laser welding system which aims at economic welding of pipelines.

A generator installed on the ARCOTRAC welding tractor supplies the laser source. The laser source is connected the to laser welding head by means of a fiber laser cable. The laser power can be transported to the laser welding head over a distance of up to 80 m. The pipes are centered and fixed to each other by means of a clamp, the pipe edges being butt welded.

The laser welding head - fixed on a band, rotates around the pipe. The result of this laser welding system is a welding speed and efficiency which is not comparable to any other welding system. A pipe of 1,000 mm diameter with a wall thickness of 15 mm e.g. can be completely welded within 2.5 minutes.

Note from Ed. The laser weld will take 2.5 minutes as long as there are no laser, pipe dimension, preperation, contamination, culture, process education, or people issues. Good Luck. For those that want less complexity than the highly sensitive laser and would like the opportunity to sleep 8 hours a day, I would suggest my simple Robo Rig or a less costly Bug-O with all position flux cored wires..

 

WHEN IT COMES TO MIG OR FLUX CORED PIPE WELD ISSUES IN THE CHEMICAL, OIL AND POWER INDUSTRIES, MIG AND FLUX CORED WELD PROCESS EXPERTISE WILL ALWAYS HAVE A GREATER IMPACT ON THE PROJECT THAN THE WELDING DOLLARS SPENT ON COSTLY ELECTRONIC WELD EQUIPMENT.

 

WHY WORRY ABOUT THE TIME REQUIRED FOR PIPE
PRE-HEAT, WITH THE VIETZ UNIT IT ONLY TAKES SECONDS:

Depending on the pipe quality it is typically necessary to preheat the pipe ends within a very short period of time. The new technology being installed on the Vietz ARCOTRAC welding tractor has been designed to reach 300o C within the shortest period of time (approx. 60 seconds).

 

 

 

 

J Ray McDermott Inc. of Houston TX gets the message,
automate, provide process controls and strive to keep it simple

With an updated automatic pipe-welding system, J. Ray McDermott Inc. (Houston, TX) continues to help set world production records for laying oil and natural gas pipelines up to 38" (965 mm) in diameter and over 0.500" (13 mm) in wall thickness. This is due in large part to having reduced the complexity of its machine control scheme.

 

 

Flux Cored

 

 

 

WHEN WELDING PIPE WELDS, CAREFULLY EVALUATE THE GAS SHIELDED FLUX CORED WIRES AVAILABLE, THERE ARE SOME TERRIBLE PRODUCTS OUT THERE.

IF YOU WANT TO SEE GOOD VERSUS MUNDANE ALL POSITION E71T-1 WIRES, COMPARE A GREAT RUNNING ESAB (ALLOY RODS) DUAL SHIELD OR KOBELCO WIRE AGAINST WHAT I BELIEVE IS A LESS THAN OPTIMUM LINCOLN, COREX OR HOBART FLUX CORED BRAND WIRES.

E-mail From John Hoffman. June 06/06:

I use all position 0.045 1.2 mm, gas shielded flux cored wires. I have been utilizing Lincoln's 71 M Outershield. Too frequently I get lots of porosity and worming. I would like to try something that works consistently. Ed what would you recommend?

Regards John.

Ed's answer: I have had many weld porosity and, worm track issues with all position Lincoln wires and also found that in contrast to some other wires, the Lincoln wires offer a lower wire feed range reducing the hourly weld deposition rate potential.

IF YOU WANT OPTIMUM AND CONSISTENT WELD PERFORMANCE FROM E71T-1 FLUX CORED WIRES, CONSIDER ESAB (ALLOY RODS) OR KOBELCO WIRES.

 

 

And the best power source for
all position E71T-1 wires is?

The lowest cost, CV MIG power source is better suited to
flux cored wires than the most costly inverter or pulsed power source.

 

Want European "confused" MIG Gas Standards Data?
Visit http://www.key-to-steel.com/GuidedTour.asp

Want European confused welding standards? Visit here

 

Keep the flux cored wires in an oven or warm dry location
to avoid porosity, worm tracks and hydrogen cracks.

 

E-mail 2005. Dear Ed, Your information in the Management Engineers book has been great!!! As I read your book, it seems like you have been inside my brain. We are now breaking away from SMAW and will be implementing Flux Core on our fill and cap passes. I will keep you informed and thank you.

Matthew Panconi
Executive Vice President Sylvan Piping NJ.

 

Ed Testing MIG and Flux
Cored Wires on Gas Pipe.

 

IN 2003, ED COMPLETED A PIPE WELD PROCESS RESEARCH PROJECT FOR IMPERIAL OIL, ALBERTA, CANADA, (THE COLD LAKE WELD PROJECT). THE PURPOSE OF THE RESEARCH, TO EVALUATE THE LINCOLN STT MODE VERSUS TRADITIONAL SHORT CIRCUIT FOR THE ROOT AND ALSO COMPARE DIFFERENT MIG, METAL CORED AND FLUX CORED WIRES FOR THE FILL PASSES.

 

PIPE MIG WELD WIRES: IF YOU WANT OPTIMUM, STEEL MIG WIRES FOR PIPE ROOT WELDS CHECK OUT AN ESAB OR LINCOLN L50, WIRE VERSUS THE COMMONLY USED E70S-X K NOVA MIG PIPE WIRES AVAILABLE FROM THYSSEN.

THE THYSSEN MIG WIRE I USED FOR THE COLD LAKE PIPE ROOT RESEARCH PRODUCED A SLUGGISH, FAST FREEZE, SHORT CIRCUIT WELD, A WELD POORLY SUITED FOR ANY PIPE APPLICATION.

DURING THE PIPE WELD AND WELD CONSUMABLES TEST, I ALSO EVALUATED A NUMBER OF METAL CORED WIRES FOR THE PIPE ROOT WELDS, AS I SUSPECTED WITH TRADITIONAL SHORT CIRCUIT TRANSFER THE METAL CORED WIRES PROVIDED NO WELD BENEFITS. IT WAS A WASTED EFFORT.

FOR THE PIPE RESEARCH PROJECT, I ALSO TRIED E80S- D2 MIG WIRES FOR THE ROOT, THESE HIGHER TENSILE MIG WIRES PRODUCED GOOD WETTING IN THE ROOT WELDS AND WITH THE LINCOLN STT PROCESS, THERE WAS NO ISSUES WITH THE E80S-D2 WIRE. WITH SHORT CIRCUIT TRANSFER, THE ROOT WELDS WITH THE 80S-D2 WIRES PRODUCED A VERY BENEFICIAL FLAT SURFACE, ALWAYS LESS CONVEX THAN THE TRADITIONAL E70S-X MIG WIRES. KEEP IN MIND THAT THESE HIGH STRENGTH WIRES OFFER LESS DUCTILITY THAT THE E70S-X WIRE SO THEY COULD BE MORE PRONE TO HOT CRACKS IN THE SMALL ROOT WELDS.

 

 

Set the flux cored wire, so the tip of the wire as close as possible
to the weld (arc length) without causing weld spatter

Fine tune the arc length with voltage control.

 

 

 

A LOW COST, FAST SOLUTION TO YOUR ROBOT AND MANUAL WELDING ISSUES. Phone / E-mail Weld Help. Ed has resolved over 1000 companies weld issues. Many weld issues can be resolved on the phone or by E-mail. [] Are you having robot or manual weld issues that affect your weld quality productivity or down time? [] Are you ready to purchase weld equipment, gases or consumables and would rather not waste your money? [] Do you want the best method or procedure for a specific MIG / FCAW / SAW / PLASMA / GTAW application? Call Ed at 828 658 3574, (eastern standard time USA). or E-mail ecraig@weldreality.com The typical weld resolution fee is $375 paid in advance with Visa or MC.   Plant Weld Help... Ed will also visit you facility and provide hands on, instant solutions to all your robot / manual MIG / flux cored / GTAW / SAW / Plasma weld issues. Perhaps you require assistance in establishing Best Weld Practices or Weld Process controls. You may want to dramatically improve your manual or robot MIG / flux cored weld quality and productivity with one of Ed's unique, one day, highly cost effective weld process control training programs. Cost $1275 daily plus exp.

 

LIKE SMAW ELECTRODES, ALL FLUX CORED WELD CONSUMABLES ARE NOT CREATED EQUAL. With the common USA gas shielded FCAW products, be aware that for vertical up MANUAL structural / pipe / pressure vessel welds on carbon steels, you can attain a higher, stable weld deposition rate from an ESAB all position, gas shielded flux cored consumable than you can from a similar Lincoln - Hobart - Corex flux cored product? Remember weld deposition rates are a primary influence on pipe line weld costs. When evaluating the gas shielded flux cored wire electrodes, for optimum welds you will require a stable/small droplet weld transfer. When evaluating all position flux cored wires; [a] Look for erratic larger drops, globular type weld transfer in the flux cored, recommended wire feed range. The glob weld transfer will provide excess weld spatter, cause arc and weld stability issues and destroy the contact tip in the over head weld positions. [b] Examine how easy the flux cored weld slag falls off the multi-pass welds. [c] Look at the wire feed settings and evaluate the MAXIMUM weld deposition attained. Ed's books show both optimum wire feed settings and deposition rates. [d] Examine the flux cored wire feed range and learn the low and high spots in which you can control the weld puddle in the overhead and vertical up weld positions. My books describe a simple method on how to set optimum weld data and evaluate a gas shielded flux cored wire.

Purchase a process control book
and become a welding pro.

BEST NORTH AMERICAN
GAS SHIELDED FLUX CORED WIRES.

 

For the best North American, all position E71T-1 gas shielded flux cored wires, I recommend ESAB 1.2 mm (Alloy Rods) products. I also like the Kobelco wires from Japan.

While I recommend Lincoln "L50" MIG wires, I have never recommended the Lincoln gas shielded flux cored products as I found they have many weld issues. In their optimum weld parameter range, the all position Lincoln E71-T1 wires I tested provided erratic weld transfer which suggest chemistry imbalance or chemistry inconsistency, also extensive worm tracks resulted. In contrast to the ESAB E710X wires, the Lincoln E71T-1 gas shielded wires also provide a narrower optimum weld parameter range, with less control of low and high amp settings. For the weld shop this means that the Lincoln wire I tested provided less weld deposition rate and less weld fusion potential for vertical and horizontal welds.

 

Remember with flux core, the adjustment of the arc
length is critical for vertical up weld control.

Volts too high weld too fluid.
Volts too low, weld spatter.

 

 

WANT TO SAVE A MILLION DOLLARS ON YOUR NEXT
SMAW PIPE LINE PROJECT? CLICK ON
" ED'S REAL WORLD APPLICATIONS".

There are many engineers involved with pipe, pressure vessel fabrication that have strong negative opinions on the MIG, pulsed MIG and flux cored weld process, yet few of these engineers will have extensive MIG or flux cored weld process control expertise.

 

 

IF YOU TAKE THE CULTURE OUT OF WELDING, LIFE WOULD BE BORING.

 

 

 

 

A comment from Mr. Bubba B. Brown Junior.
President of the BB Oil Pipeline Inc.

" Boys, for this pipe weld project, I want you all to keep the automated and pipe weld equipment costs to a minimum. We need the ability on this project to keep the weld operation as simple as possible. I want the key weld decision makers in this organization to be aware of the reasons they have to justify the purchase of so the called sophisticated electronic pipe line welding equipment.



Bubba continues. From now on I want my weld team to "ignore weld sales advice" and start make rational welding decisions for themselves. Dam it men, we need to cut through the BS that surrounds this MIG and flux cored weld process and stop hiring wimp wristed project managers and supervisors who believe the only way to weld a pipe is with a Lincoln E6010 electrode stuck up their rear end.



Bubba concludes and his blood pressure is getting pretty high. You boys take note, this is the bottom line:

[] I want this organization to be known as a cost affective, dynamic company that consistently delivers optimum weld quality and delivers it's products always on schedule.

[] I want this companies weld decision makers to have the ability to differentiate between process and equipment bells and whistles and cost effective weld benefits.

[] I want this organization to ensure the processes utilized are made simple to operate and the equipment purchased is both logical and durable.

[] Finally, I want each engineer and manager in this organization to go home to night, look in the mirror and repeat this. " I am responsible and accountable for all the process decisions made in this organization. I will do my utmost to establish Best Weld Practices for this organization and for my sub contractors. I will ensure that all weld personnel involved in this companies welded products receive the Process Control Training necessary for Process Optimization.

WE ALL KNOW THAT TO FIND A PRACTICAL, PIPE COMPANY PRESIDENT LIKE BUBBA, YOU WOULD HAVE TO HAVE A VERY VIVID IMAGINATION OR TAKE A LONG TRIP.

 

 

 

ESAB has introduced a new E71T-1 (Alloy Rod) wire called the E710X. This wire works well with CO2 or argon CO2. This flux cored wire is different in that the CO2 or argon CO2 wire feed, amps and voltage relationships are almost the same. This wire therefore has an extensive, low to high optimum wire feed and amp range making it easy to use with CO2 on a very wide thickness range.

Note: Before using this wire be aware that the moisture pick up potential may have increased influenced by the chemistry composition changes made to this wire. Before using on a large job job I recommend getting some experience with this wire.




PIPE WELDS & WELD PROCESS QUALIFIED?
Today, pipe line weld decision makers have many weld process and process combination choices when welding the pipe fill and root passes.

[1] Stick root / stick fill.
[2] Stick root / flux cored fill.
[3] Stick root / pulsed MIG fill.
[4] TIG root / stick fill.
[5] TIG root / TIG fill.
[6] TIG root / pulsed MIG fill.
[7] TIG root / flux cored fill.
[8] TIG root / metal cored fill.
[9] STT root / your choice for fill.
[10] CMT or RMD root / your choice pulsed
or FCAW for fill.
[11] Globular MIG, Pulsed MIG for pipe ID and Pulsed MIG and flux cored for fill.
[12] Laser, Laser Hybrid or twin wire.

 

 

There are always many opinions on the weld process and consumable selection for that pipe or pressure vessel application, yet I wonder how many people in the industry are sufficiently "weld process qualified" to make a rational process choice for a pipe root pass when evaluating the Short Circuit, Globular, STT, CMT or RMD weld transfer modes?

 

 

 

 

 

 

Weld process control is measured by process expertise, would you like to try this fundamental weld process control weld test?

WHEN AN INDUSTRY OR CORPORATION SUFFERS FROM WELD PROCESS APATHY OR IS SLOW TO GRASP THE WELD BENEFITS DERIVED FROM WELD PROCESS OR CONSUMABLE EVOLUTION, THE WELD DECISION MAKERS WILL OFTEN IMMERSE THEIR HEADS IN THE WELD SHOP SMOKE, SHY AWAY FROM PROCESS CHANGE AND NURTURE THEIR RELATIONSHIPS WITH THE LOCAL WELD SALES REP.

 

 

A LOW COST, FAST SOLUTION TO YOUR ROBOT AND MANUAL WELDING ISSUES. Phone / E-mail Weld Help. Ed has resolved over 1000 companies weld issues. Many weld issues can be resolved on the phone or by E-mail. [] Are you having robot or manual weld issues that affect your weld quality productivity or down time? [] Are you ready to purchase weld equipment, gases or consumables and would rather not waste your money? [] Do you want the best method or procedure for a specific MIG / FCAW / SAW / PLASMA / GTAW application? Call Ed at 828 658 3574, (eastern standard time USA). or E-mail ecraig@weldreality.com The typical weld resolution fee is $375 paid in advance with Visa or MC.   Plant Weld Help... Ed will also visit you facility and provide hands on, instant solutions to all your robot / manual MIG / flux cored / GTAW / SAW / Plasma weld issues. Perhaps you require assistance in establishing Best Weld Practices or Weld Process controls. You may want to dramatically improve your manual or robot MIG / flux cored weld quality and productivity with one of Ed's unique, one day, highly cost effective weld process control training programs. Cost $1275 daily plus exp.

ED TESTING MIG SHORT CIRCUIT
VERSUS STT / RMD MIG TRANSFER ON A PIPE ROOT.

 

 

 

2006: NEW FROM MILLER, THE MULTIPURPOSE
PIPE PRO 450 POWER SOURCE:

 

Finally after two decades of deep weld process sleep, Miller has woke up and is on its slow way to the development of a weld power source that can provide a few real world weld benefits for a pipe shop.


Before you consider the over priced, often unstable Lincoln STT/ Power Wave that sells with a wire feeder for approx. $13.000, you should examine the over priced $11.000 Miller Pipe Pro. Someone might ask, how can Lincoln or Miller justify the price of a car for the price of a pulsed MIG weld power source?

 

The Miller PipePro is a multi-process power source that can do many of the welds performed on common carbon / stainless pipe welds. The unique attribute of this power source is a Miller development called RMD (Regulated Metal Deposition).

RMD is an electronically modified MIG short circuit transfer weld suitable for all position pipe root welds. The PipePro can also use a low deposition pulsed mode the Pro-Pulse™ that actually works for all position pipe fill passes. You can also use this power source higher deposition flux core for the fill passes

The 2006 Miller PipePro. Approx. $11.000.

Before you spend $11.000 on a multi-process power source for your pipe shop keep in mind the following.

[] If most of the pipe you weld is under six inch OD and you have traditional $3000 MIG and TIG equipment and flux cored consumables. Using TIG for the root welds and flux cored for the fill passes is a great cost effective way to go.

Note: Minimal skill is required with the RMD VERTICAL DOWN ROOT WELDS HOWEVER CONSISTENT ROOT DIMENSIONS IS REQUIRED.

[] If you can rotate many of the pipes you weld, you don't need the $11.000 RMD for the root, consider regular short circuit transfer available from a $2000 MIG power source, its just as good.

[] If many of the pipes welded are > 3/8 (> 9 mm) wall thickness, the flux cored process in contrast to the lower deposition, lower weld fusion potential pulsed MIG will always be the best choice.

Note: In contrast to pulsed MIG, the flux cored process provides higher deposition rates (200%) superior side wall weld fusion and requires less skills.

[] Pulsed MIG is good choice on thin wall fill passes < 7 mm and on automated equipment that prohibits slag between the welds.

 

FOR THOSE OF YOU READY TO RUSH OUT AND PURCHASE THAT NEW MILLER PROLINE POWER SOURCE, BE PATIENT AND DO SOME REAL TESTS WITH THIS EQUIPMENT BEFORE INVESTING CLOSE TO $11,000.

REMEMBER AT THIS TIME MILLER DOES NOT HAVE THE BEST REPUTATION FOR BUILDING "RELIABLE AND DURABLE" PULSED EQUIPMENT. AND IT WOULD APPEAR THAY THEY LIKE THEIR CUSTOMERS TO TEST THEIR EQUIPMENT FOR THEM.

DON'T FORGET. ITS VERY COST EFFECTIVE TO UTILIZE LOW COST TIG OR SMAW EQUIPMENT FOR THE ROOT AND A LOW COST, CV MIG POWER SOURCE FOR THE FLUX CORED FILL PASSES.

 

And the best power source for
all position E71T-1 wires is?

]

If you want to establish Best Flux Cored Weld Practices and Weld Process Control Training, you may want to consider
MY UNIQUE BOOK AND NEW TRAINING RESOURCE.

 

 

 

 

IF YOU DON'T HAVE STT OR RMD

 

For the internal or external 1G horizontal rolled pipe root welds, set the the traditional low cost, ($2000) CV MIG process gun for traditional "short circuit transfer" with an 0.035 (1 mm) wire.

For the external root, rotate the pipe clock wise so you are welding in the vertical down weld position using the drag technique. For the root provide an 0.080 land with an 0.080 to 0.100 root gap. Set the short circuit wire feed rate at 250 to 300 ipm (around 11 o'clock wire feed control position).

Use 16 to 18 volts with argon - 15 to 25% CO2. Let the contact tip stick outside the gun nozzle and hold the MIG gun at the 2 o'clock position in the center of the pipe root gap and rotate the pipe anti-clockwise, no weaves are necessary as long as the root gap dimensions are maintained. This traditional, low cost process is simple to operate, provides great results and is done with a CV power source that could cost $1500 to $2500.

 

 

 

 

 

 

 

 

 

For internal 5G, large diameter ID pipe root welds, the all position root settings can be carried out with either short circuit or the MIG globular mode, welding vertical down. For the globular mode, use an 035 wire, a gas mix of 10 to 20 CO2 and a wire feed rate of of 400 to 500 IPM with 20 - 24 volts.

For the external root use the short circuit mode with the parameters and edge prep dimensions mentioned for the 1G position. At the cap and overhead use an aggressive weave, while at the vert down 1 to 6 o'clock position and 11 to 6 o'clock positions just use the drag technique with the wire in the center of the root gap short circuiting on the leading edge of the fast freeze weld puddle.

The pipe root pass. This task with short circuit or the newer, modified short circuit requires minimal manual weld skills and typically will attain root weld speeds of approx. .10 to 15 ipm. In contrast to a SMAW or TIG root pass, the MIG process will be done at least three to four times faster.

 

Thanks to the modified short circuit transfer, 11 old Jessie had no problem manual MIG welding a pipe line root pass, of course it took 15 minutes of instruction.

As root pass welds are simple and cost effective with modified short circuit MIG equipment, and pulsed MIG provides low deposition, all position fill pass capability, the pipe line industry weld cost / quality focus should be on the manual or automated gas shielded flux cored weld requirements for the weld fill passes when the pipe diameters are greater than 20 cm and the wall thickness is > 12 mm.

 

 

An Ed excuse for a Joke:

 

See how you do with the
flux cored weld quiz.

 

 

WELDERS WHO IN THE PAST HAVE BELIEVED THAT "SKILLS" ARE THE PRIMARY PREREQUISITE FOR ALL POSITION PIPE WELDS, NEED TO UNDERSTAND THAT WITH TODAY'S CHOICES OF MIG WELD EQUIPMENT AND CONSUMABLES, WELD PROCESS EXPERTISE IS JUST AS IMPORTANT AS WELD SKILLS.

Weld Question from UK.

Hi Ed love the site, it's a breath of fresh air. My name is Mick Brennan I work in the UK. I have been involved with the welding offshore and cross country pipelines for close on 40 years. Most of that time has been spent using Mechanized MIG Processes. Some of the processes have involved combination Internal clamping and Welding Machines. This is a fine process but it can be costly as the Pipe Ends have to be Prepped with an Internal Bevel and a Narrow Gap preparation on the outside. The money saved on less deposited metal and less welders gets eaten up with this change in Bevel Design and the costly Internal Welder. Using this equipment on shorter pipelines < 20 Miles becomes uneconomical as the pipe weld equipment is usually rented in and a mob and demob fee erodes the potential profit.

In your opinion could a Root Pass be applied to a Pipe using a Mechanized External Welding device, welding vertically down in the 5G position, 60 Degree Bevel, 1.5-2.00 mm Gap. Using a. 035 solid wire at a weld speed of 30 IPM. Wire speed 500 IPM and wire stick out of 3" with 23.5 Volts measured at the Welding Tip. In this particular area would the Pulse process be beneficial as Top and Bottom are prone to burn through and the Vertical is prone to LOP as the puddle outruns the Welding Tip?



Regards
Mick Brennan. UK.

Ed's Answer:

Mick as you know internal, pipe weld roots can be made with 0.035 MIG wires with a short circuit wire feed rate of 200 to 300 IPM with 16 to 18 volts. Also controlled globular transfer wire feed 350 to 500 ipm, 20 to 23 volts. The MIG settings you provide, WF 500 ipm - 23.5 volts are simply globular transfer.

The 3 inch wire stick out lowers the weld current and makes no sense, it does indicates a weld process out of control, and god help the gas coverage.

IN CONTRAST TO THE LONG WIRE STICKOUT USE A LOWER WIRE
FEED RATE AND WELD WITH CONTROLLED WELDING CONDITIONS.

For the external root pass, with the short circuit mode welding vert down from 12 o'clock, a fixed gap of 3/32 - 1/8 is required and there is good opportunity for weld suck back and wire stick through at the root 5 - 7 o'clock positions. X Rays don't like those wire pieces sticking in the inside of the pipe. You should weave at the top and bottom of the pipe or place long tacks in the 12 and six o'clock positions to minimize the potential root weld issues.

Modified Short Circuit
versus Traditional Short Circuit

 

Note: The above picture is a weld process pipe root evaluation carried out by Ed and Imperial Oil welders. The STT controlled short circuit current spike "no spatter" transfer weld mode is used by the welder on the left. The traditional MIG short circuit transfer mode noted by the spatter is used by the welder on right.

 

The only problem area I had with all position, external MIG pipe root welds which were made with the traditional MIG / MAG short circuit mode is found at the 5 - 7 o'clock root area of the pipe.

Thanks to suck back and weld wire getting stuck inside the root at the over head position, it's difficult to control the root gap weld quality in this area. The difficult over head root location on the pipe root pass could readily be welded during the tack operation using SMAW electrodes or the TIG process. Then use traditional short circuit vertical down for the rest of the root. Both the MIG short circuit and flux cored processes can be used with low cost generators with CV adapters OR low cost CV MIG equipment.

 

MIG and Pipe Root Tacks

If the required pipe root dimensions cannot be maintained, the root pass should be made with the SMAW or TIG process.


GOOD MIG TACK PROCEDURE: With the short circuit or modified SC mode using 0.035 (1mm) wire, place three tacks 50mm in length, then feather the tack start / stop edges. After the root pass is complete take the grinder to the length of the tacks to thin and blend the tack weld throat. For the pipe prep, with short circuit use a 2 to 2.5 mm land and a 3 mm root gap.

For modified short circuit no land is required. Use a 2.5 mm gap and use an 0.045 (1.2mm) wire. Use back hand vert down. The root throat depth of the MIG root weld will support the next hot fill pass with pulsed MIG or flux cored wire.



When the gas shielded flux cored consumables are selected for the pipe "fill" passes, pipe line companies who cannot build my Robo Rig should examine closely the need for costly, complex automated pipe weld units, versus a simple automated, carriage and CV generator for the FCAW pipe fill passes.

FOR SMALL PIPE LINE PROJECTS KEEP IT SIMPLE AND COST EFFECTIVE:
If given a choice for pipe welding the FLUX CORED fill passes between a $130,000,00 complex, automated, computerized, pulsed MIG pipe line weld package or a simple to operate mechanized, carriage / track with a CC- CV generator. The generator / with the low cost mechanized unit package can provide the following benefits;

[a] When manual or automated welding on pipe lines using flux cored wires, one volt / wire feed amp weld setting is all that will be required for the "all" the pipe fill, flux cored passes. ( weld speed and weave width will of course change). When pipe weld operators use many flux cored or MIG "weld parameter combinations" for multi-pass, fill pipe welds, it's an indication the people who set the equipment are typically not in control of the welding process.

[b] The simplicity of the 2 weld parameter controls used with the flux cored process allows the manual or automated weld operator "easy control and weld adjustment of the weld process" (especially if they have read my weld process control books).

[c] The flux cored process provides greater weld fusion than any MIG mode, it will also provide less porosity potential and require less welding skills.


[d] For pipe fill passes only. A simple low cost mechanized carriage attached to the track that straddles the pipe would sell for $10,000.00 to $15,000.00. The weld carriage should have the weld controls necessary for weld speed and weld weave controls. The weld gun would be hooked up to a traditional, field wire feeder attached to a CC / CV generator. For this weld there is no need for a complex, pulsed MIG electronic weld power source that offers 20 weld schedules and a dozen different ways to weld steels, stainless or aluminum.



The use of flux cored wires for all position pipe fill passes will in contrast to any MIG weld transfer mode, be simpler to use, easier to operate and produce much higher weld deposition rates with superior side wall fusion.


Note: If optimum flux cored consumables are selected and the flux cored weld data is correctly applied, as the following photo indicates, all the welds will be made with one set of weld parameters with changes only for the weave data. If the weld data is correct the pipe weld slag should fall off almost without assistance.

 

 

Ed's Simple Clock Method (in all his books) for optimum
MIG and flux cored weld parameter selection.

 

Correct FCAW Parameters "WOW".

E71T-1 FCAW: EASY SLAG REMOVAL IF YOU USE
THE RIGHT WELD WIRE AND OPTIMUM PARAMETERS:

The pipe weld root joint will sometimes as a result of poor fit require special considerations. The SMAW, TIG process should be given consideration when the root gap cannot be controlled

If welding the pipe line root weld on the "inside" of the pipe, the traditional low cost, CV, MIG equipment or a CV adapter on a CC generator may be used with a MIG wire using;

[1] a high short circuit setting,
[2] a controlled low globular setting,
[3] a low spray transfer setting with less than normal spray transfer weld volts.

Note: For 1 to 3, the 0.035 (1 mm) wire with argon 15 to 25% CO2 will provide the greatest control in open root pass welds.





The following statement is one many highly skilled SMAW pipe line welders will not want to hear, however it's weld reality.


Using the modified short circuit mode or traditional short circuit process for the root, a none-welding individual who has good vision, dexterity and the right attitude can be trained in a day or two to weld an all position pipe root that will meet any code requirement.

 

 

 

Lincoln Invertec STT II

Featuring the Surface Tension Transfer (STT) Process
List Price:7706.00

The STT II power source combines high frequency inverter technology with Waveform Control Technology™ to provide a better welding solution than traditional short arc MIG.



Note from Ed. This power source is great for a pipe root, however is has very limited application potential outside that pipe root or thin sheet metal weld.

 

The STT MIG root will require a root gap of 1/16 to 3/16 (3/32 to 1/8 is optimum). Provide a land of 1/16. The land is not necessary however it adds metal to the root increasing the root weld depth. With this land, a root weld throat of of 0.125 to 0.175 will result. The next weld can be made with the 0.045 flux cored wire.

STT PIPE ROOT PARAMETERS: With that 0.045 1.2 mm, E70S-6 wire and argon 10 to 25% CO2 set the parameters in the following approx. range.

Peak 320 - 360 amps, Back Ground 40 - 60 amps, Wire Feed 110 - 160 ipm.

Start out with Peak 325 amps. Back Ground 45 amps.
0.045 Wire Feed set 120 - 140 ipm.

 

Note: The optimum average modified STT current for the pipe root is also the same as the optimum short circuit current for the same application. To anyone who understands the relationship between weld current and wire feed rates, no surprise there.

Note: With the Miller PipePro equipment it's much easier to set and adjust pipe root data.

SMAW pipe welders, rather than resist the inevitable cost effective process changes for pipe line welds, reach out and embrace the manual / automated modified pulsed / short circuit transfer modes along with the flux cored process and strive to become "manual or automated pipe line weld technicians".




Feb 2004. Mr. Ed Craig: I have been welding for ten years but have never, like you say,really known the proper weld parameter settings. What would be the optimum manual flux cored weld parameter settings using .035 wire welding 6" schedule 180 pipe in the 6G position on carbon steel? I have never welded with FCAW to make a root weld in a pipe. I need to take a test on Monday and sure could use this information. I think your book " Gas Metal Arc and Flux Cored Welding Parameters " is the book I need to have and do plan to buy it. Thanks for your help and your website.

Sincerely,
Larry Fritsche


Ed's reply. I must get two letters like this every week. Two days before the welder takes a test he suddenly realizes he will not know where to set the optimum MIG or flux cored weld parameters for his critical pipe test and god help him if he uses the flux core wire on the root. I provided this data to Larry.

 

I WOULD ENCOURAGE ANYONE WHO MAKES A LIVING OUT OF MIG OR FLUX CORED WELDING TO INVEST IN A PROCESS CONTROL BOOK SO THEY CAN INVEST IN THEMSELVES.

 

Fronius Twin Wire Pipe Welding
with 4 Heads 8 Weld Wires

For those of you that feel you have mastered the single wire MIG process, or the higher deposition rate flux cored process that offers 8 to 12 lb/hr on pipe fill pass welds, perhaps are you have the process knowlege ready to set the 8 wires running on these four twin units that provide an average weld deposition rate of 60 lbs/hr. This is not a difficult application, however before you step up to this level, I would recommend my self teaching MIG process control book.

 

 

 

 

 

 

HOW LONG SHOULD IT TAKE FOR AN INDUSTRY TO
EVOLVE TO THE BEST WELD PRACTICES?

 

IT WAS DURING 1950. THE LOCATION 30 MILES NORTH OF HOUSTON TEXAS. WHILE PIPE WELDING WITH A E6010 ELECTRODE, RIP VAN SMITH, A 40 YEAR OLD, EXPERIENCED PIPE WELDER FELL ASLEEP IN A 48 INCH PIPE. WHILE RIP SLEPT THE PIPE WAS SEALED.


Being a Texan RIP had amazing powers and fifty years later RIP woke up from his oil immersed deep sleep. The unique chemicals inside the pipe had not allowed RIP to age. After crawling along the pipe for a 100 miles, RIP found a maintenance access hole. RIP crawled out of the pipe and his first stop was BeBees Barbecue Bar where he purchased a Barbecue triple Burger and washed it down two cases of Bud.

After a short nap and a long bath RIP decided to apply for a pipe line welder position on a new, natural gas pipeline that was running straight through the center of down town Houston. Wearing a new Harley tee shirt, recently stained with Bud beer mixed with a BeBees famous Brown sauce RIP took a bus out to the pipe site office.

The pipe site weld supervisor was impressed with RIP as he pulled out his brand new leather gloves and shield. With the aid of his new 10 inch bowie knife, RIP with a single strike pierced opened the metal lid of the E6010 electrodes.

RIP smiled as he held the electrode under his nose and sniffed the sweet smell of his next pay check. With a flick of his wrist he inserted the electrode into the holder and his heart never missed a beat as he commenced to produce a great vertical down welds on the 24 inch pipe.

RIP quickly completed the pipe test and the pleased supervisor hired him on the spot. That night in celebration, RIP made mad passionate love to Mary Lou Ellen, a waitress he met at BeBees. Being a Texan RIP made love for eight hours, as Mary Lou lay in a state of exhaustion, RIP leaned back on the pillow, lit a long Cuban cigar and said out loud "life don't get better than this"

There are few industries that today complete it's fundamental manufacturing tasks the same way they did 50 years ago?

I hope the present day managers, welders, technicians and engineers in the pipe and pressure vessel industry will be more open minded to the practical, cost effective weld process changes that can improve both their weld quality and productivity.

 

"WELDING CODES"

Weld decision makers often look to weld codes to provide practical, pipe welding advice and recommendations. The weld reality is the weld sections of many weld codes have been written by weld committee individuals who's strength may not be in the weld processes under discussion.


Some of the major weld code committees in North America are likely to have individuals that are more interested in marketing their companies weld products than they are in writing meaningful, logical weld spec data. Other committee members would benefit if they spent a little more time behind a welding shield before they make their flux cored or MIG weld comments.

 

 

50 YEARS AFTER THE INTRODUCTION OF THE "MIG PROCESS", AND 30 YEARS AFTER THE INTRODUCTION OF FLUX CORED ELECTRODES, THE NEWLY REVISED 03/2001 "AP1 CODE 582" STATES THE FOLLOWING ABOUT MIG AND FCAW PIPE WELDING.

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

 

PULSED MIG AND WELD PARAMETER REALITY.
In contrast to the traditional, simple, two weld parameter MIG or flux cored weld processes, there are many weld parameter essential variables that can be readily changed with the pulsed mode. The API code warns against a "SIGNIFICANT change" in a pulsed weld settings. What is "significant" weld parameter change?

Keep in mind that at best the pulsed process will only provide marginal weld fusion on vertical up welds on part thickness >6 mm. From my weld process perspective, "a minor pulsed parameter change" can have a significant impact on side wall weld fusion.

It's an ironic fact that few weld decision makers or welders understand the influence of the pulsed variables, wall thickness and weld fusion potential.

In that MIG and flux cored weld shop or out on that pipe line, you will find the majority of weld personnel do not fully understand the influence or the relationship of the pulsed MIG wire feed rate, the weld speed, voltage, the pulsed frequency, the peak and back ground current on the MIG arc plasma and resulting weld fusion potential. With all these pulsed variables in a pipe shop who in the shop is going to determine what a significant weld parameter change is?

While on the subject of pulsed, most codes do not address "mechanized versus manual" pulsed and traditional MIG weld inconsistencies".

When a code stipulates that a fusion sensitive weld process like pulsed MIG is OK for any pipe thickness, the code is sending the message that this process is recommended for both "manual and mechanized" welds.

Controlled weld speeds, fixed arc length and a controlled mechanized weld weave have a lot to do with the success of MIG weld using any mode of weld transfer. However you can be sure the traditional "manual weld weave inconsistency" would make the pulsed process a poor choice for pipe fill welds in contrast to the superior weld fusion, gas shielded all position flux cored electrodes.

ANOTHER SECTION OF THE CODE.

API. 5.2.2 Short Circuiting Gas Metal Arc Welding (GMAW-S).

The use of GMAW-S shall be limited to the following conditions:

a]. The short circuit process shall not be used for branch connections or socket welds.

(What if there is a good size root to fill in?)

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

(Have you tried uphill with short circuit?, if so you would not recommend it.)

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

(Any short circuit welds made uphill on parts over 3/16 >5 mm are sure to end up with inconsistent weld fusion)

d]. What about the weld gas? The API code does not spell out the MIG gas mix that must be used with the short circuit process or pulsed on pipe welds. Use short circuit with argon <10% CO2 and you can weld in any position and almost guarantee lack of fusion on any parts > 1/8 (>3 mm), (none gap welds).

e]. Why is it that the API code will stipulate where a process can be used but will not stipulate a simple thing like weld parameter limitations for that consumable or process?

(Is it possible the code committee are not aware of this data)?

Finally the API code makes no mention of the higher energy MIG globular or spray transfer modes, does that mean they can or cannot be used. Spray transfer can be an excellent method for a rotated hot fill pipe pass and globular is great for ID roots or hot pass welds.

To repeat an important point .

IF A CODE DOES NOT OR CANNOT PROVIDE THE COMPLETE, FUNDAMENTAL REQUIREMENTS OF A WELD PROCESS RECOMMENDATION, THE WELD REALITY IS THAT CODE SHOULD PROVIDE NO WELD RECOMMENDATIONS OR WELD RESTRICTIONS.

WELD CODES SHOULD PRIMARILY BE CONCERNED THAT WELDS ARE CORRECTLY PRE-QUALIFIED AND CONCERNED WITH THE "CONDITION OF THE FINISHED WELD PRODUCT".

2007: I REALIZE THE IMPORTANCE OF THE PIPE AND PRESSURE VESSEL WELD CODES AND THEIR CONTRIBUTIONS. MY POINT IS HOPEFULLY THAT THE NEXT GENERATION OF WELD CODE / SPEC REVISIONISTS WILL SEE THAT THEIR MIG AND FLUX CORED WELD DATA RECOMMENDATIONS DOES NOT GENERATE THE PROCESS CONFUSION THAT THEIR PREDECESSORS HAVE GENERATED.

 

NEED HELP WITH CODES AND THEIR INTERPRETATION? A rare individual and one of the world's leading experts on the ASME boiler code is a gentleman named Walt Sperko. If you need CODE expertise, contact Walt at, sperko@asme.org

 

 

 

LIKE SOME INFO ON HOW TO PREVENT ARC BLOW?

 

 

Flux Cored Weld Question: Here in Canada we are welding a 4 in. A335-P22 pipe to A234-WP22 pipe. We are using a E-91T1-B2 0.045 in. dia. Gas-shielded, flux-cored wire with a 75 Ar - 25 CO2 gas mix. We preheat the pipes to 400° F and do not exceed 550° F for the inter-pass weld temperature. The flux-cored weld current range is from 150 - 225 A. Voltage ranges from 24-29. The supervisor says all his welders have experienced massive worm tracks in the center of the weld bead usually on the cap pass. Yet it doesn't happen on every weld. I told the supervisor to reduce the weld voltage and this seemed to fix the problems. Could you explain why?

Ed's Answer: The worm tracks which are accumulated porosity typically appear in an irregular line on the weld surface. The tracks result from moisture in the electrode wire flux. This is a common problem especially with flux-cored electrodes purchased at bargain prices from wire manufacturers that simply don't give a dam.

However even with quality flux cored consumables the moisture can get into the wire flux due to inadequate weld wire storage or from no protection for the wire when it's out in the shop.Take note of the flux-cored wire manufacturers storage and baking recommendations.

The reason you see the common worm track weld problem in the pipe weld cap pass, is that this weld pass is typically the one with the least weld depth and therefore, has the fastest weld freeze, providing the opportunity for trapping porosity.

Using a slightly longer wire stick out will preheat the weld wire and this sometimes helps. I suggest you use the highest possible weld current, slow down weld travel rate, and increase the weld depth. Turning down the voltage, which is reducing weld energy, is not likely to help unless you end up with a more convex weld — a weld with increased weld depth.

 

IF YOU ARE LOOKING FOR A WELD BOOK THAT WILL ALLOW YOU TO INSTANTLY SET THE WIRE FEED AND VOLTAGE CONTROLS FOR ANY GAS SHIELDED FLUX CORED WELD THIS IS IT, TO REVIEW OR ORDER CLICK HERE.

 

Question: FLUX CORE WIRE SIZES: Ed we will be welding various diameter stainless / steel pipes in all weld positions, some welders like 1/16 and other welders like 0.052, apart from welder preference is there a logical approach to the selection of an optimum wire diameter.

Ed's Answer. Current compatibility with the part thickness and the weld deposition rate attained is what drives the selection of the correct size weld consumable. For pipes with a wall thickness < 1/2, without question the 0.045 1.2 mm gas shielded, all position flux cored wire welding in the 140 to