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At www.tiptigusa.com, you will find a weld process that always produces superior weld quality than TIG, and is 100 to 500% faster.


Welcome to the world's largest web site on MIG , Flux Cored and TIG. Weld Process Controls & Best Weld Practices. To get to the root cause of GMAW (MIG) & Flux Cored (FCAW) weld issues, requires Weld Process Control - Best Practice Expertise, & lots of Weld Reality. The site provides the MIG - Flux Cored and TIG weld information and data required to attain the highest possible manual and robot weld quality, always at the lowest possible weld costs.

This web site was first established in 1997 by Ed Craig. Contact Ed. ecraig@weldreality.com





.Each year from 1995 to 2001, an average of 408 tankers break apart at sea or barely escaped that fate, according to the International Association of Independent Tanker Owners, known as Intertanko. The leading cause was collision, but nearly as many suffered “unknown structural failures” ot technical prblems.

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Management and Ship building.

 


MIG and flux cored Weld Issues and Weld Resolutions:

 

Canadian frigates and MIG and flux cored weld Issues:

 



This Eastern Canadian ship yard management and engineers, were not aware that their yard was in a state of Weld Process Chaos: During the nineteen nineties, I was invited to provide a weld evaluation for a Canadian Ship Yard. The yard was building Frigates for the Canadian Navy. At the ship yard, most of the welding practices could only be defined "as beyond chaos."

The weld engineers and management at the Canadian ship yard had allowed the use of poor weld practices and did not appear to understand the concepts of process controls or even the fundamentals of the MIG and flux cored weld processes utilized for most of the welds on the Navy Frigates. It was also interesting for me to find out out that thanks to the management apathy and lack of management Process Ownership, the few weld engineers that were employed in the yard were not allowed to tell the welders what to do. The bottom line was the ship yard weld quality and productivity was run by the yard welders, and the majority of these welders lacked an understanding of the MIG and flux cored processes utilized.



Incorrect weld process choices and weld settings for the Canadian Navy Frigates.

When you weld a 1/4 (6mm) horizontal fillet weld with MIG or flux cored wire you use a "single pass weld" with either a MIG Spray weld, or a flux cored wire using a a high wire feed - volt setting. Both of these weld processes would provide a typical weld deposition range of approx. 9 to 12 lb/hr. In a ship yard, welding fillets, multipass fillets or groove welds, (good groove welds use fillet wire feed settings), and with a 30% hourly weld duty cycle, any welder who is well managed, would deposit on average 20 to 25 pounds of MIG or flux cored weld wire per shift.

Note. You will find that most ship yards only average 8 to 15 lbs of wire per-eight hr. shift


 

WHEN IT COMES TO WELD COSTS, HOW GOOD IS THE MIG or FLUX CORED WELD PRODUCTION EFFICIENCY AT YOUR PROJECT?

An acceptable average MIG and Flux Cored weld wire usage per eight shift day for weld shops welding parts > 4 mm should be 20 pounds / per-shift. A highly effiicient weld shop would be depositing > 24 pounds per-shift. Those shops that weld thinner parts < 4 mm, should be depositing on average between 8 - 10 pounds per shift.

To compete in a global weld market in which the Chinese are now welding bridges for the state of California, management should have the capability to understand both the weld quality requirements and the weld deposition rate potential per welder. In a large weld shop where welders weld and someone else does the fitting on parts > 4 mm, if you multiply the total welder man hours by 3, you will see how many pounds of MIG or flux cored weld wire should be deposited daily. Then call the purchasing manager, ask them to let you know how much wire was purchased and used in the previous year. With this information you will quickly get a grasp of where you are reference the weld you are depositing and your real weld production potential.

Note: Most of the large MIG - flux cored weld projects that I visited in 13 countries were only achieving 40 - 60% of the welds that they should have been daily deposited. To be aware of how to attain the weld production goals and train the weld personnel on how to achieve these weld production goals, please visit my manual MIG - Flux Cored Process Control Programs.

Note: Single pass welds are fine with horizontal fillet welds up to 5/16 (8mm). When the horizontal fillet weld size required is larger than 5/16, the weld shop would have concern for side wall fusion. The solution is to then weld the large fillet using 1/4 (6mm) stringers. Do not allow manual weaves to be used for single pass fillet welds above 5/16 as lack of fusion may occur and excess weld heat (weaker HAZ - distortion ) will be generated.

 


In the poorly run Canadian ship yard, the two prime weld processes that were daily utilized were on the majority of the welds using INCORRECT weld PARAMETERS & INCORRECT WELL PRACTICES. For example to make the 1/4, (6.4mm) carbon steel, horizontal fillet welds on the Navy Frigates, the welders would typically apply TWO WELDS that were carried out with TWO DIFFERENT WELD PROCESSES, MIG and Gas Shielded Flux Cored.

To make a simple horizontal, steel 1/4 fillet weld ON > 6 mm steel parts, the welders would first make a cold, MIG "Short Circuit close to globular weld" that deposited 5 - 7 lb/hr. This cold weld was better suited to welding thin gauge 0.080 (1.8 mm) sheet metal. This first weld pass had to result in Frigate welds that had extensive lack of weld fusion. To finish the 1/4 fillet welds, the welders would do something which revealed the complete lack of weld control in this Canadian Navy yard. For the second weld pass on the fillet weld, the welders changed their weld process to gas shielded flux cored. With the flux cored wire they used the same wire feed and voltag as they had used with the MIG wire, (no playing around with these guys they just ued one incorrect setting for any weld). The flux cored wire feed and volt settings used ensured that the welders were placing a cold flux cored weld over the top of the cold short circuit - glob welds.

 



SOMEONE FORGOT TO TELL THE CANADIAN NAVY FRIGATE SHIP BUILDING MANAGEMENT, "THAT WHEN THEI WELDERS USE INCORRECT, COLD WELD PARAMETERS, THEY WILL END UP WITH A COSTLY WELD DEFECT, AND WE THAT HAVE SOME PRIDE LEFT IN THE WELD PROFESSION, CALL THAT DEFECT "LACK OF WELD FUSION."


The majority of the two fillet pass welds on the Canadian Frigates would reveal extensive lack of weld fusion and weld porosity. Also the cold flux cored welds would result also in extensive lack of fusion and slag entrapment. Each day using inappropriate weld settins and practices, the 200 - 300 ship yard welders would have produced hundreds or thousands of feet of single - multiipass welds on each Navy frigate. It should come as no surprise to those reading this, that as I walked around the yard and talked to the key weld decision makers and too many welders I did not manage to talk to anyone who knew what MIG Short Circuit, Globular or Spray Transfer was, and even fewer understood the optimum working parameter range and best weld practices required for the E71T-1 flux cored wires..
Note: Many of Canadian Frigate welds under discussion only required visual surface examination, and this is the crutch that enables poor poor weld management to pick up a pay check.


COSTS: THE AVERAGE WELD DEPOSITION RATE AT THE CANADIAN YARD WAS 4 - 7 LB/HR.
The MIG short circuit - globular parameters that were used with the 0.045 (1.2mm) wires were set at a the SC typical wire feed rate of 210 to 280 ipm, (average 5 - 7 lb/hr) which typically produced 180 to 230 amps with 19 to 22 volts, (20 plus volts promotes glob and excess spatter).. Without question, the majority of these welds would result in extensive lack of weld fusion, on any carbon steel parts > 4 mm.
The flux cored data that also use these settings was better suited to a poor quality "vertical up weld," The average flux cored weld deposition would have been 4 - 6 lb/hr.


 

Ed's MIG Spray, Single Pass fillet. 045 wire. 450 ipm - 28 volts. 12 lb/hr

 

COSTS: THE AVERAGE DEPOSITION RATE AT A WELL RUN WELD SHOP THAT WELDS THE SAME PARTS WOULD BE 9 - 12 LB/HR.

Ffor those few mgrs, engineers or supervisors . that have an interest with weld process control and cost info. To make a single pass, horizontal,1/4 fillet with the 0.045 flux cored wire, you would typically set approx. 500 inch/min, (average 9 - 10 lb/hr) with 27 - 28 volts. For the MIG process a wire feed rate of approx. 420 - 450 inch/min, (average 11 - 12 lb/hr).


..

.

The more one learns about ship welds,
the less one is inclined to go on a ship.


Its possible that your Navy's worst enemy
may be the welds on its ships..

.

.

IF MANAGEMENT, ENGINEERS & THEIR WELD SUPERVISION DO NOT FULLY UNDERSTAND "WELD COSTS", THE SUBJECT IS NOT LIKELY LIKELY TO BE PART OF THE DAY TO DAY WELD SHOP CONVERSATION:

To put salt in the Canadian Frigates ship yard management wounds, every weld produced with the low wire feed (low deposition rate) settings, took each of the 250 - 300 welders approx. 30 to 400% longer than it should have.

This Canadian yard simply had no effective weld management and ironically spent over a million dollars annually on "welder training" which resulted in extraordinary poor weld productivity and quality. Not that anyone gives a dam, but the low weld deposition rates and unnecessary weld rework could readilyy result in Canadian tax payers paying > 10 plus MILLION dollars per year on unnecessary weld labor costs.


I delivered my weld report to the yard management. The report provided the required data and practices for the yard to get it's welds to the quality and productivity that they should have been attaining.

I was later informed that my weld report never got as far as the first manager who reviewed it. The report then disappeared into the nearest garbage container. I was later told by the key weld suppler to the yard that the manager was too embarrassed to present the report to his executive team, and also he did not want the Canadian Navy Brass to be aware of the weld quality produced and the unnecessary yard over costs generated by the welds.



ALL WELD DECISION MAKERS SHOULD FOCUS ON THEIR BEST WELD PRACTICES - PROCESS CONROL EXPERTISE. USING MY SELF TEACHING - TRAINING RESOURCES
, IT'S EASY TO GENERATE MULTI-MILLION DOLLAR COST SAVINGS WITH ANY LARGE SCALE WELD PROJECTS:



.Each year from 1995 to 2001, an average of 408 tankers break apart at sea or barely escaped that fate, according to the International Association of Independent Tanker Owners, known as Intertanko. The leading cause was collision, but nearly as many suffered “structural/technical failures” — often a euphemism in industry circles for excessive corrosion or structural problems.

.

 

 

 



INTHIS USA SHIP YARD, I PROVIDED PROCESS CONTROL - BEST PRACTICE TRAINING WHICH REDUCED THE OIL TANKER CONSTRUCTION WELD REPAIR COSTS BY > 6 MILLION DOLLARS PER SHIP.

In building a fleet of oil tankers in Philadelphia, Aker Kvaerner, a global ship building company had budgeted a few hundred thousand dollars per-ship for its projected ship weld repairs. In 2007, I was called in to help this yard with it's weld quality and productivity problems. At this time the weld repair costs per oil tanker was approx. eight million dollars.

The prime manual weld process at this USA ship yard, was the Gas Shielded Flux Cored weld process. Most of the 300 welders in the yard used E71T-1 (1.2 mm) flux cored wires to weld all position, Vee Groove, 9 to 25mm, steel joints that used ceramic backing for the open roots.


Like many ship yards, the Aker management, engineers and QA personnel knew little about the flux cored and MIG processes, their experience was usually with the SMAW (stick) process, a process in which weld skills is the prime requirement and minimal weld process expertise is requied.

In this yard, as it is with too many large scale weld projects, the flux cored welder training focus was on the "welder's skills", and the skills taught had more to do with the SMAW process and were not the optimum skills - practices required for flux cored. As is common in most ship yards, the training provided no best weld practices and process controls, both of which are essential to optimize both flux cored and MIG weld quality and productivity.




To work at the yard, the welders had to pass an all position, flux cored weld tests with ceramic backed vee groove welds, (6 mm root gaps) The welds were to be made in accordance with the yards weld procedures.

TOO OFTEN, "WELD QUALIFICATION TESTS" ARE IRRELEVANT TO THE WELDS MADE ON THE ACTUAL WELD APPLICATIONS.

It's important to emphasize, that like many code quality weld applications, the weld - welder qualification tests will too often have little in common with the real world weld joints typically found in the weld shop or the yard.

This ship yard was managed by managers - engineers and supervisors who while comfortable around a box of stick electrodes, lacked the awareness - expertise of the unique requirements necessary to attain consistent optimum manual or automated flux cored weld quality for those ceramic backed steel groove welds. In the last five decades, the lack of valuable weld process control - best practice expertise appears to be common on large scale weld projects, and it does not take a rocket scientist to figure out the future weld liability and the weld cost consequences.


THE EXTRAORDINARY OVER BUDGET SHIP YARD WELD REWORK COSTS WOULD NOT CHANGE TILL I INSISTED THAT ALL THOSE INVOLVED, INCLUDING THE FRONT OFFICE PERSONNEL ATTEND MY TRAINING SO THEY WOULD ALL FULLY UNDERSTAND THE WELD PROCESSES THEY OWNED.


For the Flux Cored Weld Best Practices - Process Control Training Program that I was to present, I insisted that all the welders, supervisors, engineers, managers and QA personnel in the yard participate in my unique
Note for the bean counters: This weld process training program requires approx. ten hours, "five hours classroom and five hours hands on".

With my best friend Tom O'Malley assisting, Tom in light blue jkt on right died in Feb. 2015.. RIP TOM and keep your eye on me. In a few weeks, we completd the training for approx. 300 welders and the yards newly eductated weld decision makers.


After the training was complete, the ship yard QA department was given the responsibility to evaluate the weld cost saving results through the weekly reductions with the ship's weld rework. Three months after the training, the ship yard QA department indicated a 50 - 60% reduction in the required weld rework per-ship. The ship yard management reported that the reduced weld rework, labour and NDT costs, would result "at that time" in a weld cost savings of approx. 4 million dollars per-ship. As the weld rework was still decreasing further cost reductions were projected and dont forget I have not discussed the increased weld productivity that was attained from the welders using the correct (higher) wire feed settings.


Ed's MIG and flux cored self teaching or training programs are available at
this site




HOW MANY MORE DECADES WILL WE REQUIRE FOR MANAGERS TO REALIZE THAT SMAW HAS NOTHING IN COMMON WITH MIG OR FLUX CORED AND THESE TWO PROCESSES HAVE UNIQUE REQUIREMENTS?

It's not unusual for weld personnel to have many weeks of flux cored hands on training at global ship yards, and then at the training completion find that when it comes to MIG and flux cored welds, the weld personnel that have under gone weld training will do the following;


[a] PLAY AROUND: Many welders will play around with two simple MIG or flux cored weld controls that have not changed in sixty years, The welders and their supervisors will rarely be able to dial in the optimum flux cored weld settings for the Vee groove root, hot pass, fill pass and cap passes. And don't ask that welder to tell you the optimum MIG settings for that common horizontal 1/4 fillet weld.

[b] NOT BE AWARE OF PROCESS CONTROLS AND LIMIT THEIR WELD ADJUSTMENTS: Instead of optimizing the welds through the MIG weld equipment controls, many welders will typically find one weld setting and if they cant find one, the welder may copy the settings of another welder although that welder is doing a very different weld. A welder should be able to make optimum weld parameter changes that suit the conditions they have to deal with. Imagine how annoyed a machine shop supervisor would be, if his lath and milling machine operators used one control setting for every different job they were given.

[c] NOT BE AWARE OF THE BEST WELD PRACTICES? As they have rarely received best practice training, it should be no surprise that most MIG and flux cored welders will not utilize the optimum weld practices - techniques required for either the MIG or flux cored process.


[d] NOT BE AWARE OF THEIR INFLUENCE ON WELD COSTS? Lack of management, engineer, supervisor and welder awareness of the wire feed to weld deposition relationship and the weld deposition rate potential for the common flux cored or MIG welds certainly makes it difficult to be competitive and to control weld costs.



A BREAK DOWN OF THE WELD COST SAVINGS GENERATED FOR THIS USA SHIP YARD:

Examine the following ship yard weld cost reduction and the weld benefits attained from my unique process control training program. Many mangers may not be keen on training as in the past the weld training did not improve the weld quality or productivity. (Managers, if you dont provide the right training you don't get the results). Training cost money, and the larger the weld shop the greater the training costs. With this in mind it should be no surprise to find some one in management that may be worried about the production man hours lost for training their employees.

Weld Best Practices - Process Control Training Costs:


The Acker training program I produced, required 300 x 8 man/hrs. = 2400 man hours at an approx. weld labor overhead cost of $30/hr. The base labour training cost for the ship yard training was $72,000. To this add the actual training and material costs was approx. $100,000.
Total training costs for the 300 welders was approx. $172,000.


Shipi Yard Weld Rework Cost Reduction Savings Per-Ship:

The initial weld improvement results revealed an instant savings of
four million dollars. With management - engineering and supervision focus on maintaining the skills - process control expertise required, the reduction in weld rework costs will continue and could easily reach 7 million dollars on each oil tanker produced.

Ship Yard Weld Cost Reduction from Increased Weld Productivity:

An unreported weld cost fact from the Aker yard was the changes that I created in the development of the new weld procedures. My weld procedures generated a dramatic increase in the gas shielded flux cored wire feed rates, (increasing the weld deposition rates). The new weld procedures increased the daily weld productivity potential per-man in the range from 25 to 35%. If the managers and supervisors kept their focus on weld deposition potential, it would be easy for the yard to attain a weld labor cost reduction per ship of between four and five million dollars.

Ship Yard Weld Cost Reductions from welding the Correct Size Weld Joints:

If this ship yard manufacturing management, engineers, supervisors and fitters, decided to provide the weld joints in accoradance with the design dimensions and tolerances it would be easy to reduce the weld labor and rework by another 1 to 2 million dollars per-ship.


Ship Yard Management - Ownership - Responsibility - Accountability.

The weld quality - labor cost reduction savings for each oil tanker could if well managed readily achieve "8 to 13 million dollars" per-ship. Larger ships built at this yard would provide increased weld cost savings. The welders have the skills which when combined with the best practices and process control training they recieved has given them the resources they require. To sustain the weld cost savings and weld quality, a commitement is required from the yard management to ensure that they and their engineers and supervisors maintain ownership of the weld processes utilized and be responsible and accountable for the weld quality and productivity attained.


Note I took > 2500 - 3000 hours to develop both the Flux Cored - MIG training programs available at this site. My unique Weld Control Clock Method simplifies the training or self teaching, this is a method I developed over three decades. This program can be used for any gas shielded flux cored alloys or applications. The program is available here

My thanks to the Aker
Kvaerner management for allowing me to be their short term catalyst for welding change
.

 

 

 


1945 0R 2015, When will they ever learn ?

 



In the good old STICK (SMAW) weld days which for some projects is ongoing, some steel ships broke apart at the welds before they left the dry dock.

These and the catastrophic structural failures that occurred at sea, were often a result of low hydrogen cracking, poor weld practices, steels with poor chemistry (high impurities) and design ignorance of plate - weld mechanical properties and the influence of cold temperatures.

Since the 1980's the majority of ships have been built from high quality,low carbon steels and welded with low hydrogen SMAW - MIG and flux cored consumables. You would have thought these two important attributes would have resolved the catastrophic ship failure issues that occur in >2008.

Lets face it, welds on low carbon steels, are typically supposed to surpass the strength and ductility of the base steels and if the welds are applied correctly, the
welds and surrounding base metals are not supposed to fail.

The reality is however different, while many ships and oil platforms have plate and pipe that will be affected by rust, during unforeseen circumstances or severe weather while the steel parts impregnated with rust stay intact, the welds and weld heat affected zones will tear apart like a wet paper bag.

03/ 2007: Is it possible that the global ship building flux cored, lack of best weld practices and lack of weld process controls are partially responsible for many of the catastrophic failures that sink many ships each year?

 

 

ABOVE, A COMMON FABRICATION ATTITUDE.

 



THE USA SHIP YARD HAD EUROPEAN, HIGHLY QUALIFIED SHIP BUILDING MANAGEMENT, AND A LARGE QA AND ENGINEERING DEPARTMENT, YET THEY ALLOWED WELD JOINTS LIKE THIS..

It's a weld reality that the QA departments in many ship yards and oil platform yards, while looking for weld defects the QA department personnel will place minimal focus on the design fit tolerances and the quality standards that are supposed to be applied to the part fit and weld edge preparations. Its also a fact that pre-heat and interpass weld temperatures are often not utilized when they could provide good weld / part benefits
.


The picture on the left is a flux cored weld edge prep (made in 2007) at a major USA ship yard. Yes the gap opening is larger than one inch and that is ice and water surrounding the weld joint. On this joint there was no weld preheat applied and no interpass weld temperatures applied during the numerous welds. To add to this pathetic weld situation, the mill scale was left on the groove edges and cutting oxides were left on the groove surfaces. Weld joints like this shoud never be allowed especially in these industries.

The increased root openings not only dramatically adds to the weld labor costs and increased potential for weld defects, the weld heat from the additional weld passes has a tremendous negative influence on the weld's HAZ (heat affected zones).




2007: WE SHOULD ALL KNOW THE ANSWER TO THIS QUESTION.

DOES A STEEL BACKED, 6 mm ROOT GAP ON SHIPS PLATE, PROVIDE THE SAME HAZ MECHANICAL PROPERTIES, WHEN THAT ROOT GAP IS ALLOWED TO INCREASE IN THE RANGE OF 8 TO 25 mm.?

WITH THE EXTRA WELD PASSES FROM THE OVER SIZED ROOT WELDS, THE RESULTING , INCREASED WELD HEAT AND INCREASED WELD DEFECTS WILL HAVE DRAMATIC NEGATIVE RESULTS FOR BOTH THE WELD AND WELD JOINT INTEGRITY. WITH THIS IN MIND, YOU WOULD EXPECT THE SHIP YARD ENGINEERS TO PROVIDE STRICTER SHIP YARD WELD REQUIREMENTS AND ENSURE THE CORRECT FABRICATION AND WELD CONTROLS ARE APPLIED.

Weld - steel qualification tests for critcal ship weld plate joints are typically taken from optimum weld joints with specified max root gap openings. It would be of interest, if the navy and ship building industry, both of which turn a blind eye or enable welds that allow extensive, plus, open root tolerances, would provide the necessay research to find out the following;


[a] what the negative weld heat influence will be from the numerous extra weld passes.

[b] what the negative consequences will be from the combinations of the extra weld defect buildup and extra weld heat would be on the mechanical properties,

[c] what is the real world maximum root gap cut off point before the mechanical properties will be outside those specified by the ship's designers? After this research, I would anticipate a dramatic reduction in the open root tolerances, more focus on interpass temperature controls and and stricter part fit controls in the fab shops.

The additional HAZ weld heat provides many questions about the mechanical properties being achieved with many weld joints. Every time I see photos of ships that unexpectantly tear apart at sea, and you see that nice clean straight tear where the welds HAZ is located I think about these weld situations.





Quick, before it sinks, examine how nice and clean the catastrophic failure tears are, right down the weld seams and their HAZs...


2007: The weld failures on this ship occurred in the locations in which the welds should have been sound, as they would have be subject to NDT. With ship welds we need more focus on the weld quality that is being accepted and on the mechanical properties being attained in the weld's HAZ.

 

 




2007: It's a weld reality that in ship yards and on other mega oil and natural gas projects, that many unacceptable variables will happen to the weld joints and welds and those "variables that impact the welds are typically not considered in the pre-qualification welder procedures generated".

When the weld personnel are not supplied with the process control training necessary to deal with the weld shop variables, the welders will typically play with the weld controls and not provide optimum weld settings to deal with the weld situations.


Weld Quality Standards will have a different meaning for each company that builds ships or oil platforms. One thing most QA departments will have in common, is their weld quality focus will be on "finding rather than preventing weld defects".


Have we learnt anything about welding ships in the last six decades?

29/07 Note from Ed:

Designers and metallurgists will typically look to the ship's design, steel - alloy compositions, environment, water temp, weather and the formation of rust for the causes of many catastrophic ship failures. I wonder how many designers will take into account that on any global built ship the NDT that examines the internal weld quality is only applied to a small percentage of the ships welds.

IRRESPECTIVE OF THE WELD CODES, COMMON SENSE WOULD ENSURE THAT ENGINEERS CREATE PRE- QUALIFICATION WELD TESTS THAT ALLOW FOR THE REAL WORLD "WORSE CASE WELD SITUATIONS THAT ARE LIKELY TO TAKE PLACE WITH THE INTENDED WELD APPLICATIONS".


 

 

Poor Welds and the Consequences.

Shit, it broke apart right along the bloody weld seams, and it was not much of a storm.

 

 


Many ship yards forget that oversized weld joints require many more weld passes producing extra weld heat (larger HAZ) and more internal weld defects. An increase in weld defects with a weaker plate HAZ is not a combination any organization should accept.

While the ABS code, Navy or any ship builder will stipulate a maximum root gap allowance in most instances its rarely adhered to. The weld reality is weld and material metallurgical weld qualification tests should always be carried out with the maximum allowable root gaps and those root gap dimensions must have strict min and max tolerances that must be followed. Unfortunately as the photo on the left indicates this is the real world weld joints that are rarely shown in the engineers office.

When building merchant or naval vessesls, the too common poor control of the weld joint will often leave edge preps that have irregular, oxide and scale laden surfaces. The edge preps may also not have the required pre-heat on those cold or wet days. The wet plates or cold plates, lack of pre-heat combined, oxides - scale and frequent lack of interpass controls with innapropriate weld parameters, techniques and practices, and the usual lack of care of the consumables leads to extensive lack of weld fusion, weld slag inclusions, porosity and lower than required plate / weld mechanical properties..

As only a small portion of a ship's welds are typically subject to NDT, both the navy and merchant navy would do well to put a renewed focus on weld process control training that is directed at weld defect prevention and good weld practices. All managers need to be aware that it's just as easy to produce optimum quality welds as it is to produce poor welds.

 

 



The following are a sample of recent news paper or web reports on typical weld and related issues that have occured in ship yards. It's true that with large scale weld fabrications it should be no surprise that they are extensive weld issues. It just seems strange that few managers today seem to want to take opportunity to take ownership ot their processes and control of the many variables that can provide dramatic weld cost reductions for their organizations.


 

 

 

When building the USS Nimitz, as reported by the Navy, only one weld out of approximately 100 tested passed the NDT.

 

 

 

 

Was the ship's or OIL platform demise from a freak of nature, or from poor welds?

MOST DESIGNERS ASSUME THAT THE SHIPS OR OIL PLATFORMS THAT THEY DESIGN, WILL BE BUILT IN ACCORDANCE WITH THE WELD SPECIFICATIONS PROVIDED. THE WELD REALITY IS FEW ARE. THE REASON WHY MANAGEMENT - ENGINEERS GET AWAY WITH POOR WELD CONTROLS AND PRACTICES IS, IT'S DIFFICULT TO TEST AND CONFIRM THE OVERALL WELD INTEGRITY ONCE THE SHIP YARD OR OIL PLATFORM IS ON THE OCEAN FLOOR.

 

 

The amount or type of weld defects typically found in a ship's construction in 2015, has hardly changed from the defects found six decades ago.

 

 

 


In the 1940's, poor quality stick (SMAW) welds were the norm. The weld quality was further influenced by electrode issues combined with poor quality steels and poor weld practices. The end result was numerous Liberty ships suffered from catastrophic weld & steel failures.

Seventy years later, in general (there are of course exceptions) in the weld industry we have achieved what.? Today we have a superior flux cored wires for those all position ship plate - pipe welds. We also have the MIG process and good automated weld equipment. We also weld on far superior quality steels, yet due to the global lack of weld process control expertise, the too common poor weld practices and the ineffective (we take no ownership) weld management, ships and oil platforms are riddled with costly weld defects and these applications are still at risk for catastrophic failures.

 

<1960: 5000 liberty ships built, 1000 catastrophic
failures right down te weld seam.




Decades later,oil platforms heading down to the ocean floor




 

 

For those looking for the structural security attained from the double hull construction that will occur when building large ships or more costly ships, keep in mind that unless ship yards change their approach to weld best practices and process controls, the double hull ships may simply enable double the amount of bad welds.

 

 

 

HOW RELEVANT IS SHIP DESIGN WITHOUT SOUND WELDS:




2006: Each week one or two global ships sink, many as a result of weakened
structures from corrosion.
Does anyone ask how many ships sink annualy as a result of bad weld practices, and why do ships appear to get torn apart in calm waters?

 

 

The US automotive industry that this year had 60 million vehicle recalls, loves the infamous and highly ineffective Six Sigma Crutch and this management crutch is now heading to other industries whos management also requires a crutch. Ship yards and large weld fab shops are showing interest in the SS even after it has failed with the majority of manual and robot MIG and flux cored weld applications found in US automotive and truck plants. Remember when it comes to welding MANAGEMENT does not need a crutch, they do need weld best practices and process expertise.



 

THE QA SYTEM (typically finds, rather than prevents weld defects) USED THROUGHOUT THE WELD INDUSTRY OFTEN DOES LITTLE TO REDUCE THE LIABILITY POTENTIAL..... While the QA manager focuses on the ISO and his never ending after the weld fact inspection reports, the lack of affective process control training, the lack of weld best practices and the lack of management - supervision process expertise in his organization leaves many of the ships welds in a precarious situation.

 

 

 

 

Be a professional with the processes and consumables utilized.

 


A note from Ed Craig. 03/2007:


A ship yard may use half to a million pounds of flux cored weld wire each year, however it's rare to find a ship yard that has management and engineers who have established Best Weld Practices and implemented effective Flux Cored Weld Process Control Training for the weld personnel.


How many ship yard managers and supervisors are aware of the following?

For decades the global shipyard focus has been on the welder's "stick welding skills while the majority of global ship yard welders that weld with the flux cored - MIG process, lack weld best practices - process control and consumable expertise.

Too many weld personnel in ship yards will daily use the unsuitable techniques and skills they learnt with the lower weld energy, lower weld deposition stick welding process
.

With the flux cored process, the variable size root gaps and the placement of weld across none conductive ceramic backing requires unique weld considerations and specific instructions for the all position, root, fill and cap weld passes. A visit to any global ship yard, would reveal that few welders, supervisors or "engineers" are aware of the flux cored process and ceramic requirements necessary for consistent weld optimisation.

2008: It's a sad comment in a time when MIG and flux cored weld defects inundate ships and oil platform construction, that at many global ship yards, weld apprentices will spend more time practicing with stick electrodes than they will with MIG and flux cored consumables. It's also a weld reality that many weld instructors when providing MIG and flux cored training, will teach the apprentices inappropriate stick welding practices and techniques. You dont want to ask any weld instructor in a ship yard this fundamental MIG question. " What is the wire feed and current start point of spray transfer with the world's most common 0.045, E70S-6 MIG wire and argon - 20% CO2"..




YOU CANNOT CONTROL THE WELD QUALITY - PRODUCTIVITY
AND COSTS IF YOU CANNOT CONTROL THE PROCESS.




Try the following fundamental weld process questions
.

 

[] Fundamental MIG Process Control Weld Test

[] Fundamental Flux Cored Process Control Weld Test.

[] Ed's Unique, MIG and Flux Cored Weld Process Control Training Resources

 

 

 

It looks like someone needs a lesson in ship building.

Accountability - Responsibility - Ownership....36 million in repairs and 400 million
over budget & the seniior management and engineers are still on the job.

 

HOW "NOT" TO BUILD A SHIP, BUT HEY WHO CARES,? IT'S ONLY TAX PAYERS DOLLARS:

NORFOLK - The new amphibious ship San Antonio failed to complete a series of sea trials in late March, and faces $36 million in repairs during the next three months.
The San Antonio has been plagued by mechanical and structural problems since the Navy took ownership two years late, in July 2005. Northrup Grumman Ship Systems in Pascagoula, Miss, built the ship at a cost of $1.2 billion, roughly $400 million over budget.

With optimum flux cored weld consumables and extensive use of a grinder, the gas shielded flux cored process is perfectly able to produce optimum, all position quality welds on any steel applications as long as those applications have weld joints that meet the design and code criteria.

The bottom line is MIG or flux cored welds on any ship should be the strongest part of the ship. The reality with too many structures welds are creating the weakest link.

 


IF I MANAGED A SHIP YARD THE FIRST EASY THING TO FIX WOULD BE THE QA DEPARTMENT.
For decades, on many mega weld projects, a typical QA / CWI primary function has been to "find fault after the weld completion". With minimal cost managers could provide my Weld Process Control - Best Weld Practice Training Program and demand that their weld inspection personnel learn the requirements necessay to prevent the MIG or flux cored weld defects. The reduction in weld defects, less weld rework and much lower NDT costs, has to have a big impact on the companies bottom line.



If the guys in the front office don't fully understand weld costs, who is going to understand the requirements necessary to attain optimum quality welds at the lowest possible cost?.

There are ten individuals comprising of managers, engineers and supervisors having a weld meeting in the ship yard managers office. The meeting was called to discuss the reasons for the increasing weld costs associated with the weld rework. Most of the welds are made on fabricated components that require simple 1/4 flux cored fillet welds. The weld procedure is passed around with information on the consumable type and size, the wire feed rate and the volts being utilized. There is much finger pointing at the afternoon shift guys on the shop floor The discussion is heated and tempers are on the rise. The manager is a pragmatic individual who admits he knows little about weld costs, he stands hits the table, looks around the room and says, "gentlemen there appears to be much confusion here and little expertise, is there one of us in this room that can tell us the real cost of a 1/4 fillet weld one meter in length"?.

You know that if you were in that meeting, instead of the few minutes to provide the correct answer, it would likely take many hours of more discussion and then the answers provided will be all over the place. Then again, possibly the manager should never have asked the question in the first place as he is part of the problem.


Note from Ed, please don't shoot the messanger.

Sometimes I feel that my comments on this site may be seen by some as a little too critical, however there is a reason this site is called "weld reality" and I don't just criticize, I provide highly effective practical weld quality - productivity and cost solutions. To those who are interested in weld best practices and process controls or weld cost simplification, click here.



Concerned about weld costs and weld liability consequences?

For those weld shop managers and engineers that live behind glass walls and are rearing up in defensive exasperation at my hands off, inexperienced manager - supervision and engineer comments, and my criticism for the general lack of global lack of process control - best practice expertise, please remember that their will be thousands of weld shops this year that will have to deal with lower weld labor costs from other companies in other states / provinces or countries, over budget weld costs, inconsistent and poor weld production efficiency, over budget NDT costs, and extra weld rework costs.

The typical common unexpected weld - part issues will of course lead to tighter production schedules which typically makes the weld situation worse as the weld shop supervision now has to drive more production before quality. And lets not forget, the lack of process ownership ensures all involved will continue to work too many hours and loose too much sleep.

 





WELD LIABILITY CONSEQUENCES ARE MANY..

 






Every person who makes a weld decision, should learn weld process controls and understand the requirements to prevent defective welds

 



With all the money Ed makes from his weld consulting, he has made

the down payment on his dream "house boat".



I wonder how many weld shop managers, supervisors and engineers would last in their jobs, if every weld they were responsible for, was given a 100% UT or radiograph examination?









This ship yard welder was allowed to weld USA oil tankers for three years,
and this was his best attempt at a welder requalification test.

|

 

 


The weld equipment and consuambles purchased in a weld shop are always a reflection of the weld or fabrication managers expertise.

PURCHASE OF RIDICULOUS WELD EQUIPMENT
AND LACK OF FUNDAMENTAL BEST WELD
PRACTICES AND PROCESS EXPERTISE..


Take a moment look around your weld shop. Watch as the weld personnel "play with their MIG and flux cored weld controls". Evaluate why you are using a wide variety of unnecessary weld consumables and weld equipment. Go to your gas cylinder rack and ask your self whay there are more than two gas mixes. Chat with the purchasing mgr and find out how much was spent last year on grinding wheels and other equipment used for cleaning welds. And last, find out how much was paid last year for service, repair and maintenance costs" associated with the electronically sensitive welding equipment and weld guns purchased.





SHOULD THERE BE DOUBLE STANDARDS APPLIED TO WELDS AND
SHOULD THE SO CALLED CRITICAL SHIP
WELDS BE MANUAL OR AUTOMATIC?

 

In my world every weld produced on a ship or used to fabricate a work bench should be considered critical, after all, whats the purpose of a weld? and why would you not ensure every weld produced is optimum. Also why would any manager allow double standards for welds:

In the ship yard, the structural welds in the center area of the ships are considered critical and subject to internal NDT weld evaluation. When NDT finds defects in these welds, then more weld area is subject to the NDT. This has great weld cost repercussions for the ship builder so these welds are given extra consideration and often the best welders are used on these joints. The point is in any facility that welds, if the correct training is provided there should be no best welders. Welding is not rocket science and there is only one standard that can be applied to all welds. If after the proper training is provided, you get rid of the welders who cannot meet that standard.

In many of the weld facilities that I visit, I note manual welders typically will make long fillet or vee groove welds, when low cost, easy to set up, automatic weld carriage equipment is on a shelf gathering dust. Controlling weld speed, weld weaves and wire stickout is essential if you want to attain consistent, optimum, uniform weld quality.

In the encouragement for flux cored or MIG weld automation, one of the problems ship and oil platform companies have, is that due to lack of weld process expertise, especially with the supervisors who should be providing the automation weld training, many welders do not know the correct data to dial in for the common 3/16 - 1/4 - 5/16 fillet welds. Ask 10 welders in a yard what is the MIG or flux cored "wire feed and weld travel rate settings" are for a 1/4 (6 mm) fillet weld and I guarantee you will get 10 different answers.


I have assisted ship yards in the USA, and Canada and in Europe. At the yards I worked with Norwegian, Swedish, Danish, German, Polish Italian. English, Korean, Japanese, Yanks and Canadians and and don't forget those tenacious thick skinned, highly intelligent, hairy, canny Scottish weld personnel. My experiences with these hard working, great characters indicated that the majority played around with their weld controls and none had ever received MIG or flux cored weld best practice - process control training, or training in dealing with ceramic backed welds.

From my ship yard experiences, i developed thicker skin, an increased sense of humour and also developed the following flux cored, CD. Best Practices - Process Control Training Resources. This program is applicable to all position, open root, steel and ceramic backed, pipe and plate, fillets and vee groove welds.

For Ed's "MIG and Flux Cored" Weld Best Practices - Process Control Training resources.

 

 

WELD MANAGEMENT STARTS WITH "PROCESS - EQUIPMENT AWARENESS":


The first step for ship yard management is be aware of the level of weld process control expertise and reponsibility of the key weld decision makers in the yard. Lets face it, If these guys knew what was needed to minimize weld defects and optimize weld productivity, then the weld and rework costs would not be out of control.

Weld quality responsibility should be in the hands of managers, engineers, technicians and supervisors. Typically the weak link in this chain are the weld or fabrication supervisors. The irony is the supervisors are given more responsibilty for the welders than the engineers and technicians get. Notice that QA persons who find weld defects after the welds are complete are not included.

IF AN ENGINEER IN A SHIP YARD THINKS A WELDER IS NOT CAPABLE OF PRODUCING THE WELD QUALITY DESIRED, HIS OPINION ON THAT WELDER WILL HAVE LESS MEANINING THAN WHAT THE LESS QUALIFIED SUPERVISOR'S OPINION MIGHT BE.


The second step for ship yard management is the managers have to be aware that the weld equipment, process and consumables used in their yard rarely reach their full weld quality and productivity potential.
The soution to this is in the training programs provided. Yard management have to be aware that the MIG and flux cored welder training programs provided for weld personnel are obviously not effective, therefore training changes are required and training focus is necessary on teaching all weld personnel best weld practices and weld process controls




The ship yard management needs to be aware that the stick (SMAW) weldesr with 20 years experience typically only brings incorrect techniques and bad weld practices to the MIG and flux cored process? There is a global shortage of welders. If the weld management was aware that when new welders walk into their yard, few will have seen a ceramic backed root gap. If something like ceramic backing is unique or rarely utilized in other industries, that means welder's need to undersatnd the best practices and process controls necessary for welding on none conductive ceramics.

As its difficult to hire drug free welders, I dont want to waste ship yard money on testing welders to fail. Before testing welders I would give them a one day training on the best practice and process controls necessary for the process and consumable used in the weld test. I would also provide the welders with the optimum weld settings. With this logic ship yards would have less issues hiring welders?



As a matter of interest to the few managers that read this stuff please note. Any "none welding person" with the right attitude and provided with the correct skills, best practices and process control weld training, should with "ten days training" be able to meet the all position code weld quality requirements necessary for the majority of MIG and flux cored welds in any ship yard.


MANAGEMENT ENSURES SHIP YARD WELDER TRAINING DEALS WITH THE YARD WELD VARIABLES:


[] While the ship yard management complains that their weld over cost per-ship is one to ten million dollars, they allow the ship yards fitters to produce oversize weld preps that typically add 30 to a 100% more weld.


[] In ship yards, thanks to lack of management / engineering focus on providing weld joints that are in compliance with the design, its not uncommon to find weld joints outside the code requirements with variable root weld gaps from 8 to 25 mm. These welds will be made. How will the welders react to the techniques and parameter changes required when welding across the extra size ceramic root gap.

[] How does the welder react when the weld procedure does not requ
ire preheat but the steel is either wet or cold.

[] How does the welder react when they have to put in twice as many welds that are specified in the procedure but there are no interpass temp controls or information about additional weld passes?

The ship and oil platform welders are daily offered unique challenges by fabrication supervisors who frequently know little about the flux cored or MIG process, supervisors who deliver weld joints that are simply not acceptable. To make their job a little more complex, ship yard welders often have to make the challenging welds on the poor oversized edge preps in 20 mph winds, 50 feet up on a scaffold, at minus 20 degrees.



THE FOLLOWING ARE A FEW WELD VARIABLES FOUND ON SHIPS AND OIL PLATFORM PROJECTS. THESE VARIABLES ARE THE REASONS WHY WELDERS REQUIRE THE ABILITY TO WALK UP TO THEIR WELD EQUIPMENT AND INSTANTLY SELECT OPTIMUM WELD PARAMETERS FOR THE THINGS THAT ARE ABOUT TO IMPACT THEIR WELD QUALITY OR PRODUCTIVITY POTENTIAL.


[] narrow, inconsistent root gaps,
[] variable and excess root gaps,
[] a lack of understanding of the unique weld requirements
necessary for ceramic backed roots with variable gaps,
[] poor weld edge preparations,
[] welding on primer, paint, rust and cutting oxides,
[] welding in an inconsistent daily changing environment,
[] difficult weld access,
[] extensive difficult, vertical and over head welds,
[] recieving weld joints from ship yard fitters who have never been educated on the cost consequences, the quality liability potential or difficulties of welding poor weld joints,
[] supervisors, managers and engineers making flux cored and MIG process and equipment welding decisions, when the reality is, their
weld knowledge never got past a E7018 stick electrode.

 



PREVENTING HYDROGEN CRACKS:

What about those ships being built with the higher strength and low alloy steels? My gut instinct tells me that if a ship yard cannot control the weld issues that occur with the common low carbon steels, that ship yard will not provide any better controls on the higher strength or low alloy steels.

In the good old days when welders deposited a leisurely three or four pounds of stick electrode a shift, they would be concerned about the sponge like flux on the stick electrodes and it's attraction for The stick electrodes would be protected (sometimes) in a heated storage oven or electric portable heater.


Most welders on large projects typically only produce 50 - 60%
of the weld they should be producing.



Today MIG and flux cored welders on large projects should be depositing a minimum of 20 - 23 pounds of weld wire a shift, (few do). The reality is during the construction of many ships and oil platforms, that due to the lack of supervision - management focus on attaining weld deposition rates, most welders will typically deposit only 10 to 15 pound of flux cored weld per shift.

Due to lack of logical flux cored weld best practices, few weld facilities ask the welders to date and time tag new wire reels utilized. Whats normal is the flux cored wires are left out in cold, damp or humid conditions for god knows who knows how long.

In contrast to stick welding, which has the flux on the surface of the electrode, a primary benefit of the flux cored wire is the wire's flux is protected by an outer steel sheath. Some wire sheaths have a straight butt seam and it's easy for them to allow moisture through the seam, other wires like the one in the picture have seams that are designed with a little more consideration for keeping moisture away from the flux. With flux cored wires you get what you pay for.


Gas shielded flux cored wires are supposed to be low hydrogen products, however that definition only applies as long as the weld wire is sealed in it's container. The flux in these wires or the wire surface can readily be be contaminated with moisture, and show me a ship yard where moisture is not an issue.


Ed's flux cored, process control training program available on a CD also
deals with the weld practices necessary for all weld defect prevention.

 



WHAT IT TAKES TO GET HYDROGEN CRACKS STARTED:

[] High strength steels.

[] Large root gaps, plate misalignment, anything that results in excess weld heat and excess stresses.

[] Lack of control on the steel surface contaminates.

[] Lack of control with preheat and interpass temp controls.

[] Lack of history and protection for the flux cored weld consumables used.

[]
Lack of awareness of the potential for moisture in the welding gases utilized

[] Lack of process and weld technique knowledge that could help minimize the effects of moisture

[] Lack of concern for the quality of the weld gases used. Many cylinders and pipes supplying MIG and flux cored weld gas mixes, will contain moisture.




WITHOUT BEST WELD PRACTICES AND PROCESS CONTROLS,
THOSE WELD CRACKS WILL HAPPEN.


It's inevitable that on that on that one billion dollar naval vessel,containing high strength steels, that when that vessel leaves the docks, it will leave with hydrogen cracks.

To add misery to misery, the cracks will typically be in the weakened weld's heat affected zones, along side welds that are bound to contain lack of fusion, slag inclusions and extensive porosity.



Please remember when building a ship, or an oil plat form, a failed weld can have the same consequence as those weapons of mass destruction.





INVESTIGATION OF FRACTURED STEEL PLATES REMOVED FROM WELDING SHIPS.

Corporate Author : PENNSYLVANIA STATE UNIV UNIVERSITY PARK

Personal Author(s) : Williams, M. L. ; Meyerson, M. R. ; Kluge, G. L. ; Dale, L. R.

Abstract : Samples of fractured plates from 72 ships were examined, and various laboratory examinations and tests were made on 113 plates selected from these samples. Information regarding the structural failures involved was obtained from the cooperating agencies, and the failures were analysed on the basis of this information combined with the results of the laboratory investigations. The ship weld failures usually occurred at low temperatures, and the origin of the fractures could be traced, invariably, to a point of stress concentration at a geometrical or metallurgical notch resulting from design details or from welding defects.

Note from me: Fifty six years have passed since the above reports. When will ship yards get control of the common welding processes they utilize?

 

 



THE SUPERSTRUCTURE ON FFG 7 CLASS SHIPS HAS EXPERIENCED EXTENSIVE CRACKING. THE CAUSE OF THE CRACKING HAS BEEN DETERMINED TO BE A COMBINATION OF HIGH DESIGN STRESS COUPLED WITH POOR WELD QUALITY





I had a good laugh in 2005 when I read in the AWS magazine about some VP in a ship yard looking at purchasing a CO2 laser for ship welding applications.

This was a yard I was familer with. It was a yard in which the management and engineers were unable to get control of the simple to use, two control, MIG - flux cored process. This was a yard where the managers had a difficult time getting their weld personnel to feel comfortable with simple Bug-O welds, (mechanized MIG or flux cored carriage welds). This was a yard in which none of the weld management understood the cost of a weld. This was a yard in which the managers and supervisors lacked the ability to provide edge preps and weld gaps that meet the design specifications for flux cored weld, and now this is a yard in which the management wants to to bring a laser into their yard.



IN MY WORLD, A SHIP YARD WOULD BE RUN LIKE A NAVY SHIP:

Ship yard management would do well to compare themselves with the way the navy runs a ship and submarine. A captain or engineer on these vessels typically has the ability to operate or take apart most things on the ship. I am not suggesting that today that this comprehensive, technical expertise should be part of this generation's manufacturing managers job description, (it should however be part of an engineers job description). I am suggesting that in 2012 the global weld industry would benefit from a compromise in which managers and engineers have less reliance on salesmen or weld equipment rep and show more ownership interest in the equipment responsible for building their products.


To get manufacturing management and engineers back into the weld equipment process control loop, an important first step would be for these individuals to show the workers that when they open their mouths on the subject of welding, they can provide welders on the shop floor something most don't have "weld process control knowledge"
.

If you are looking for excellent MIG and flux cored weld process control knowledge resource, it's here.





IF MANAGERS, ENGINEERS AND SUPERVISORS LACK THE ABILITY TO CONTROL
THEIR WELD PROCESSES, THEY WILL TYPICALLY LEAVE IT THE THOSE LOWER PAID
GUYS IN THE WELD SHOP TO EVALUATE NEW OR DIFFERENT WELD TECHNOLOGY.




2001: The evolution from the shielded metal arc welding (stick) process, to the gas shielded flux cored welding process has for many pressure vessel shops, pipe shops and pipe line contractors been painful and slow. The flux cored wires that offered many practical benefits for all position welds were developed > twenty five ago. The weld reality for those industries that weld pipe lines or and code projects with the SMAW process, is the gas shielded flux cored weld process evolution for most all position code application should have taken a few weeks.

Note: When the management and engineers don't provide weld process ownership, the so called weld decision makers will leave it to their welders to test new weld wires or gas mixes.

Some of the greatest resistance to the uses of flux cored wires came from the global pipe weld shops that supply the oil industry. These weld shops like ship yards were entrenched in SMAW (stick) weld practices, and the unqualified reps who were selling the flux cored wires lacked the process expertise necessary to optimize the flux cored weld performance and therefore could not convince the stick pipe welders to accept the superior flux cored process.

The majority of welders will lack the best practices and process control expertise necessary for weld consumable evaluation, and therefore the new consumable weld test results will often be poor. Also what motivation will welders have for going outside their comfort zones and recommending something new that would require major learning curve changes for the shop?

HAPPY WITH A PROCESS THAT REQUIRES MINIMAL PROCESS CONTROL EXPERTISE:
As the SMAW equipment provides a single weld current control, the STICK welder simply increases or decreases the weld current and therefore needs minimal weld process control expertise. In most instances even the choice of the electrode is made for the welder.
In contrast to the SMAW process, the MIG equipment that's also used for flux cored welding allows a welder to use seven distinct modes of weld transfer for MIG - FCA welds..

The reality today in 2012 is that most of the weld shops that use the common MIG and flux cored processes will have focus on the welder's skills rather than on the welder's weld process control expertise. Every day in these weld shops you will find that the MIG equipment and consumables are rarely used to provide their full weld quality - productivity potential and therefore every day weld costs are more than they need to be. The upside is in most weld shops there is always good potential for dramatic weld cost savings.

WELDERS WILL NOT FEEL COMFORTABLE WITH WIRE FEED PROCESSES UNTIL SOME INDIVIDUAL STEPS UP TO THE PLATE AND TEACHES THEM THE BEST PRACTICES AND PROCESS CONTROLS NECESSARY TO OPTIMIZE THESE TWO PROCESSES. PLEASE NOTE. YOU DO NOT NEED WELD EXPERTISE TO PRESENT MY UNIQUE WELD PROCESS CONTROL TRAINING RESOURCES.

 

 



HOW BAD WELDS KILL.

History of USS Thresher (SSN-593)
Related Resources:

 

In company with Skylark (ASR-20), the USS Thresher put to sea on 10 April 1963 for deep-diving exercises. In addition to her 16 officers and 96 enlisted men, the submarine carried 17 civilian technicians to observe her performance during the deep-diving tests. Fifteen minutes after reaching her assigned test depth, the submarine communicated with Skylark by underwater telephone, appraising the submarine rescue ship of difficulties. Garbled transmissions indicated that--far below the surface--things were going wrong. Suddenly, listeners in Skylark heard a noise "like air rushing into an air tank"--then, silence.

Efforts to reestablish contact with Thresher failed, and a search group was formed in an attempt to locate the submarine. Rescue ship Recovery (ASR-43) subsequently recovered bits of debris, including gloves and bits of internal insulation. Photographs taken by bathyscaph Trieste proved that the submarine had broken up, taking all hands on board to their deaths in 5,500 of water, some 220 miles east of Boston. Thresher was officially declared lost in April 1963.

Subsequently, a Court of Inquiry was convened and, after studying pictures and other data, they said that the loss of Thresher was in all probability due to a casting, piping, or weld failures that flooded the engine room with water. This water probably caused electrical failures that automatically shutdown the nuclear reactor, causing an initial power loss and the eventual loss of the boat.

 

How lack of metallurgical expertise
and cold water helped destroy the Titanic.

True Titanic Facts

 


Eight More Ships with Structural - Weld Problems.

From Marine Log Home Page:

Italian classification society RINA, Genoa, says its initial findings on the causes of the sinking of the Maltese-flag tanker Erika during a major storm in December point to a small structural failure or leak low down in the hull structure. This was followed by cracking that eventually led to the collapse of the hull.

RINA says its investigations prove that the calculated residual strength of the vessel at the time of the casualty should have been sufficient to withstand normal operation of the vessel in the prevailing weather. The residual strength was within IACS limits.

Initial investigations show that the hull structure initially failed at some point low in the hull, and that complete failure occurred only after cracks had propagated from that source.

RINA is continue its investigations to determine the cause of that initial failure and the results of the subsequent actions of the master, owners and other parties involved. RINA will focus on several potential causes of the initial failure, including:

[] possible poor loading or poor ship handling,
[] poor workmanship during weld repairs,
[] failure of welds due to poor design and poor weld practices during it's construction.

RINA has appointed Three Quays Marine Service and Studio Tecnico Navale Ansaldo to conduct further independent investigations covering: design and construction of the Erika and its seven sister ships. "Eight sister ships of the Erika class were built, under two different class societies, and have been classed by five different IACS classification societies at some time in their lives. All of these ships had suffered structural problems. Three of them, other than the Erika, were serious. No information on this history of problems was available to RINA," he says.


Side Note: It appears that in the case of the Prestige and the Erika tankers that the structural failures occurred a few months after welding repairs were carried out on the hulls. This would suggest that welding could be a factor in the structural failures.

 

 

IF THE BAD WELDS DONT GET YOU, MAYBE THE RUST WILL:

 

 

THE NEW SUPERTANKER PLAGUE
By Richard Martin

--------------------------------------------------------------------------------
Blame it on super-rust, a virulent form of corrosion that has destroyed hundreds of ships and could sink the oil industry.
--------------------------------------------------------------------------------


On December 7, 1999, the oil tanker Erika set sail from Dunkirk, France, bound for Sicily, carrying 10 million gallons of heavy fuel oil. A few days later, the ship headed south around the coast of Brittany and cruised directly into a powerful storm.

The Erika battled swells of more than 20 feet as it steamed across the Bay of Biscay. Soon the ship began to list, and 11-foot cracks appeared in the deck and hull. The Erika was breaking apart. A helicopter evacuated the crew just before the vessel split in half and sank in 400 feet of water, spreading tarlike petroleum across more than 250 miles of the Loire-Atlantic coastline — Europe’s largest oil spill in two decades.

Built in Japan in 1975, the Erika was typical of today’s older tankers. Sailing under the flag of Malta, it was managed by an Italian operator and chartered by a Bahamian company headquartered in Switzerland. Its Maltese owner was itself owned by two Liberian firms. Deemed seaworthy by Registro Italiano Navale — one of many organizations, known as classification societies, responsible for inspecting and certifying commercial vessels — the Erika had passed every inspection over the year prior to its sinking.

The final report on the disaster, issued in January 2000 by the French investigative agency Bureau d’Enquetes sur les Accidents en Mer, concluded that severe corrosion had weakened the Erika’s hull, causing the ship to flex in the storm and eventually to fracture.

The volume of oil moving by ship is soaring. And in traditional tankers, accelerated corrosion is engineered right into the body of the vessel.


The Erika was neither the first nor the last tanker to succumb unexpectedly to corrosion. Each year from 1995 to 2001, an average of 408 tankers broke apart at sea or barely escaped that fate, according to the International Association of Independent Tanker Owners, known as Intertanko. The leading cause was collision, but nearly as many suffered “structural / technical failures” — often a euphemism in industry circles for excessive corrosion and bad welds .

Ships have been corroding since the late 18th century, when wooden hulls were first covered with copper to protect against worms. Mariners have recognized the threat to steel tankers in particular since the 1950s, and classification societies have established a regime of inspections and maintenance to keep corrosion at bay. But the system has failed. Ships that cost hundreds of millions of dollars to build are falling apart on the open sea, endangering the lives of crew members and spilling millions of gallons of oil each year.

For instance, the Nakhodka went down two years before the Erika sank. This 27-year-old tanker broke apart off the coast of Japan, spilling 1.3 million gallons of crude and killing one sailor. The Japanese Ministry of Transport found that portions of the ship’s hull had rusted 20 to 50 percent. In December 2000, the Castor, carrying 8.7 million gallons of unleaded gasoline across the Mediterranean, developed cracks in its deck and had to be drained of its cargo in a risky ship-to-ship maneuver.

Preliminary findings in the Castor case rocked the industry. According to the American Bureau of Shipping, the classification society that certified the vessel, the Castor had fallen prey to “hyper-accelerated corrosion” — swiftly dubbed “super-rust” in the trade press. The ABS downgraded its assessment to “excessive corrosion” in its final report, issued this past October. Nonetheless, that document noted that the vessel’s steel had disintegrated at rates of up to 0.71 millimeter a year — more than seven times the “nominal” rate expected by the bureau. (The ABS declined numerous requests for an interview. David Olson, the Colorado School of Mines professor who served as the “independent” metallurgist for the Castor report, also refused to comment.)

Super-rust was initially explained as an unprecedented phenomenon, a highly evolved form of corrosion neither foreseeable nor preventable. The truth is less mysterious: Hyper-accelerated corrosion is the inevitable result when unforgiving chemistry meets the harsh economics and tangled industry politics of transporting fossil fuels.

Rust attacks steel from the moment the metal encounters moisture. To keep that from happening, ship owners paint steel surfaces with corrosion-resistant coatings. The coatings break down with age; conventional maintenance protocols dictate that tankers be recoated periodically. If all this is done properly, any ship should carry cargo for 30 years or so and then retire to the scrap yard without incident.

But first-class ship maintenance has become increasingly rare in recent decades. Since the 1970s — when the Erika, Nakhodka, and Castor were built — profit margins in the tanker business have fallen steadily. Today, tankers change hands two or three times before they’re taken out of service. Temporary owners of second — or third — hand ships tend to be less interested in maintaining their vessels than maximizing the return on their investments. What’s more, the classification societies lack the authority to enforce rigorous standards. These nongovernmental agencies depend for revenue on their clients: shipbuilders, owners, and operators, who can and often do shop their business to competing societies. For instance, the Erika’s owners switched to Registro Italiano Navale after the French agency Bureau Veritas, which had certified the ship for the previous five years, refused to overlook its deterioration. The Erika went down just 18 months later.

So far, super-rust has destroyed only old ships at the end of their useful lives, allowing many in the industry to maintain that the problem is contained. This complacency has become increasingly dangerous in the face of evidence that the latest generation of tankers is even more vulnerable than its predecessors. Ever since the Exxon Valdez ran aground in 1989 — the worst spill in US history, dumping 11 million gallons of crude into Alaska’s Prince William Sound — shipbuilders have focused on constructing tankers that would be impervious to grounding and collision. The solution has been to wrap a second hull around the first; the Oil Pollution Act of 1990 mandates that, by 2015, all tankers operating in the US have double hulls. This innovation has prevented dozens of spills, but it has inadvertently propelled corrosion to unheard-of levels.

Tales of double hulls rusting far more rapidly than expected began to circulate in the early ‘90s, not long after the first such vessels entered the water. The 5-year-old Mobil tanker Eagle, for example, spent almost three months dry-docked in Singapore in 1998, reportedly having her cargo tanks treated for corrosion. According to Seatrends, a leading trade magazine, the Eagle had leaked oil into the space between its inner and outer hulls. (Contacted earlier this year, an ExxonMobil spokesperson repeated the company’s assertion that the ship docked in Singapore for “routine maintenance” and that no leakage had occurred.)

Fearful of government regulation, the shipping world has attempted, as Seatrends editor Ian Middleton put it in a 1999 editorial, to “keep a lid” on such incidents. But inspections keep turning up severe corrosion in new tankers. A 2000 Intertanko report concluded that excessive rust is afflicting double hulls within two years of launch. Without a serious shift in industry practice, it won’t be long before the first double hull goes the way of the Erika.

Rust arises from an intricate subatomic dance in which water’s oxygen and hydrogen atoms snatch electrons from atoms of iron. Because saltwater conducts electricity better than freshwater, the iron in steel oxidizes more quickly in seawater — up to 0.10 millimeter per year, as foreseen in classification-society manuals. Given enough time, this process can eat through even the thickest hull.

The way corrosion attacks the interior of a tanker, however, is more insidious. It can be seen most vividly in the cargo tanks, which line up along the ship’s backbone beneath the deck, and in the ballast tanks that cushion the cargo tanks along their outer edges. In these areas, steel deteriorates at five, ten, even thirty times the nominal rate.

In the ballast tanks, which are normally filled with seawater when the cargo tanks are empty, water conducts electrons between plates on either side, and between separate areas of a single plate — that is, the tanks become huge, if weak, batteries. The increased electrical activity hastens the metal’s degradation. To combat the problem, shipbuilders have traditionally installed bars of reactive metal like zinc or aluminum inside the tanks. The added metal becomes a “sacrificial anode,” which corrodes in place of the ship’s steel. Known as cathodic protection, this method has become less popular as paint manufacturers have developed rust-resistant coatings over the past 20 years or so. In the absence of cathodic protection, however, corrosion sets in when coatings break down. Shoddy repairs can also play a role. In the Castor, corroded plates discovered during inspections were replaced with new plates of uncoated steel, turning the uncoated metal into a sacrificial anode. Thus, the patches rusted even faster than the original metal had.

The processes that drive ballast-tank corrosion hasten the familiar action of oxidation. What happens in cargo tanks, on the other hand, involves more ruinous chemical and biological forces.

At the top of the cargo tanks, the vapor space between the oil’s surface and the underside of the deck traps highly acidic gases — products of the reaction between petroleum, oxygen, and water — that condense against the metal. The deck flexes at sea, causing degraded steel to flake off the ceilings of the tanks, exposing more bare steel for the acid to attack. Examining this area isn’t easy. Scaffolding must be constructed inside empty, unlit tanks, and even then inspectors can view only small portions up-close.

At the bottoms of the tanks, in the water that settles under the oil, corrosive bacteria thrive. Consuming hydrocarbons, microbes like Desulfovibrio desulferican produce acids that dissolve the tanks’ floors and lower sides at rates as high as 2 millimeters per year. Some microorganisms even feed on the coatings that protect the tanks from rust. Essentially, a tanker is a gigantic floating petri dish for a peculiarly vicious sort of steel-eating sludge — the ultimate metallivore.

Super-rust in aging single-hull vessels can be blamed on an industry in denial. In double hulls, accelerated corrosion is engineered right into the ships themselves. The extra layer of steel gives rust many more square feet of surface area to attack, much of it hidden in cramped, inaccessible crawl spaces. What’s more, these crawl spaces form an insulating layer that keeps the internal temperature much higher than it would be in a single-hull tanker. Corrosion rates tend to double with each 20-degree Fahrenheit increase.


At the same time, manufacturing efficiencies have reduced the thickness of hulls and decks. Guided by software modeling, designers put plenty of steel where it’s needed for strength, while reducing it in the rest of the structure. The advent of high-tensile steel — stronger than conventional steel but no more rustproof — has allowed naval architects to further pare down the metal structure.

These developments have led many shipbuilders to trade corrosion-resistance for lower cost. Every ounce of steel saved in the construction of a new ship translates into greater profits for the builder and reduced fuel bills for the owner. Between 1970 and 1990, the amount of steel used to construct a tanker declined by almost one-fifth, according to Tankers Full of Trouble, a 1994 book by Eric Nalder based on his Pulitzer Prize-winning Seattle Times series. Modern tanker walls are only 14 to 16 millimetres thick, compared with 25 millimeters a generation ago. Assuming a microbial corrosion rate of 1.5 millimeters a year, rusted-out pits would reach halfway through those hulls in five years.

Even without a spill, the consequences of an internal breach leaking oil into a double hull could be catastrophic. Asked what might result, shipbuilding consultant Rong Huang gives a one-word answer: “Explosion.”






Polar Resolution.

All ships look old unless they’re freshly painted. At the Avondale Shipyard, upriver from New Orleans, the only unblemished metal surfaces are rails that support rolling dockside cranes and the gleaming blue sides of the state-of-the-art tanker Polar Resolution. Every other steel surface in the yard is dusted with flash rust, a ruddy patina that appears almost as soon as the steel is exposed to air. This superficial oxidation is sandblasted away before the metal is painted and coated. Some surfaces, however, never get coated at all. These unprotected areas invite the risk of destruction from within.

Contracted by Polar Tankers, a division of Phillips Petroleum, the Polar Resolution is one of four $230 million ships designed for the iceberg and reef-strewn run from Valdez, Alaska, to Puget Sound. The 895-foot vessel has not only a two-layer hull but duplicate engine rooms, navigation systems, and propellers. Its 12 cargo tanks hold 42 million gallons of oil. When its sister ship, Polar Endeavor, set sail last spring, Professional Mariner magazine named it Ship of the Year.

A series of ladders and stairways descends steeply to the floor of the Polar Resolution’s empty cargo tank number five. The walls rise 100 feet to the main deck. A band of light streams from the hatch high above. From the inside, the tank is like a vast steel cathedral, a shrine to man’s thirst for oil.

The tank floor is covered with epoxy. But overhead, the vapor space is uncoated — contrary to classification-society recommendations.

This expanse of bare metal is a stark emblem of the industry’s failure to face up to the hazard of corrosion. With each disaster or near-disaster, authorities have launched an investigation. When corrosion has been implicated, the result has been a litany of recommendations that hardly varies from year to year: Coat the vulnerable surfaces of the ballast and cargo tanks, inspect them frequently, and remove substandard tankers from service. But these guidelines are honored mostly in the breach. According to the ABS report on the Castor, the ship’s last inspections “failed to adequately represent the condition of the vessel’s structure.” In other words, the investigators missed the damage.

Supertankers are the biggest moving structures ever built, yet the system for constructing, inspecting, and certifying them is a relic of the 19th century.

At one time, the classification societies were adjuncts to the marine insurance business. Today, they call themselves the self-regulating arm of the shipping world; the avowed mission of the ABS, for instance, is “to serve the public interest as well as the needs of our clients by promoting the security of life, property, and the natural environment.” In practice, the societies serve the shipowners. The leading organizations, which include the ABS, Lloyd’s Register in London, and Det Norske Veritas of Norway, are staffed by conscientious experts, but they work within a system where no one is answerable for the condition of the ships. There is no FAA for tankers.

 

What’s more, the tanker industry is overrun with so many holding companies, limited-liability partnerships, and owners-of-record that even determining who bears ultimate responsibility for a ship can be difficult. Authorities investigating the Erika found the owner’s capital structure so opaque that it was nearly impossible to figure out who controlled the company. Following the inquiry, Paul Slater, chair of shipping conglomerate First International Group and a member of Intertanko’s Communications Committee, declared the current inspection system “monstrously outdated.”





Most American tax payers are rarely aware of where their taxes go and some goverment weld - bld rework costs can be extraordinary.


According to the program office the LPD 17 Amphibious Transport Dock, which was delivered to the Navy in July 2005, experienced numerous quality problems of varying degrees that significantly impacted the ship’s mission. These problems contributed to a delay of 3 years in the delivery of the ship and a cost increase of $846 million.


In June 2007, the Secretary of the Navy sent a letter to the Chairman of the Board of Northrop Grumman expressing his concerns for the contractor’s ability to construct and deliver ships that conform to the quality standards maintained by the Navy and that adhere to the cost and schedule commitments agreed upon. Northrop Grumman’s Chairman acknowledged that the company was aware of the problems and is working on improving its processes.

The LPD 17 encountered a problem with the isolators on titanium piping. The isolators are used to separate different types of metals to keep them from corroding. The problem was discovered in 2006, about a year after the launch of the first ship. According to DOD program officials, the titanium piping is used throughout the ship because it is lighter than the traditional copper-nickel piping and has a longer service life. However, it has not been used much in naval surface ships or by the American shipbuilding industry, and therefore required new manufacturing and installation processes. According to the program office, these processes were being developed as Northrop Grumman Ship Systems was building the ship. In addition, designs for the piping hangers, which hold the piping in place, as well as tests of the isolators were subsequently delayed. When the titanium piping on the ship was changed, the hanger design had to be modified as well. The final hanger design was not completed until about 90 percent of the titanium piping was already on the ship, which resulted in additional rework and schedule delays.


(Note from Ed. Welding Titanium. It would have been an easy task with TIP TIG which was available at this time.


The ship alsp encountered problems with faulty welds on P-1 piping systems, a designation used in high-temperature, high-pressure, and other critical systems. This class of piping is used primarily in hydraulic applications in engineering and machinery spaces. P-1 piping systems require more extensive weld documentation than other pipes as they are part of critical systems and could cause significant damage to the ship and crew if they failed. Welds of this nature must be documented to ensure they were completed by qualified personnel and inspected for structural integrity. Further investigation revealed that weld inspection documentation was incomplete. As a result, increased rework levels were necessary to correct deficiencies and to re-inspect all the welds. Failure to complete this work would have increased the risk of weld failure and potentially presented a hazard to the ship and crew. According to the program office, a contributing factor was turnover in production personnel and their lack of knowledge on how to complete the proper documentation.

Note from Ed. If people are not doing their job, not qualified to do the job, it's time to hire qualified managers who can rectify these situations.





THE FOLLOWING IS A REASON YOU CANNOT APPLY DOUBLE STANDARDS TO SHIP OR OIL PLATFORM WELDS:




AS THIS NEXT ARTICLE INDICATES. EVERY WELD SHOULD BE CONSIDERED A CRITICAL WELD:

 


 

Authors KITUNAI, Yoshio (Japan Crane Association)
KOBAYASHI, Hideo (Yokohama National University)


On March 27th, 1980, the semi-submersible platform Alexander Kielland suddenly capsized during a storm in the North Sea, because one of its five vertical columns supporting the platform was broken off. 123 workers among the 212 people on board were killed in the accident.

The investigation showed that a fatigue crack had propagated from the double fi
llet weld near the hydrophone mounted to the tubular bracing D6. As a result, the five other tubular bracings connecting to the vertical column D broke off due to overload, and the column D became separated from the platform. Consequently, the platform became unbalanced and capsized. After the accident, the offshore design rules were revised and some countermeasures were added to maintain a reserve of buoyancy and stability for a platform under a storm.


Cause (1) Fracture features
A circular hole was introduced to the underside of the D6 bracing, and a pipe, which is called a hydrophone, was mounted into the circular hole by welding. The hydrophone was 325 mm in diameter with a 26 mm wall thickness. The hydrophone was welded using a double fillet weld with a weld throat thickness of 6 mm. A drain of the bracing D6 had to be installed at a location 270 mm away from the hydrophone.

As a result of examination of the welds of the D6 bracing, some cracks related to lamellar tearing were found in the heat affected zone (HAZ) of the weld around the hydrophone. Traces of paint coinciding with the paint used on the platform were recognized on the fracture surface of the fillet weld around the hydrophone in the bracing D6.

The paint traces show that the cracks were already formed before the D6 bracing was painted.
Examination of the fracture surface also showed that the fatigue cracks propagated from two initiation sites near the fillet weld of the hydrophone to the direction circumferential to the D6 bracing. Moreover, the fatigue fracture surface occupied more than 60% of the circumference of the D6 bracing (Fig. 7), and beach marks were formed on the fracture surface, which was about 60 to 100 mm away from the hydrophone. Striations with spacing of 0.25E-3 to 1.0 E-3 mm were observed in patches on the fracture surface of the D6 bracing.

(2) Characteristics of the welds of the hydrophone. Considering of the importance of the strength of the D6 bracing, welding of the drain into the bracing was carried out carefully according to the design rules. In the case of the installation of the hydrophone, however, a circular hole was made on the D6 bracing by gas cutting, and the surface of the hole was not treated by some process, such as a grinding. After cutting, a pipe, which was made by cold bending and welding using a plate with 20 mm thickness, was mounted into the hole of the bracing, and the pipe was attached by welded around the hole by double fillet welding with a throat thickness of 6 mm.

When the hydrophone was installed by welding, the weld defects, such as incomplete penetration, slag inclusion, and root cracks, were introduced in the welds, because of the poor gas cutting and welding practices. Moreover, lamellar tearing related to inclusions in the material used was found near the HAZ of the hydrophone. The stress concentration factor, Kt, of the fillet weld of the hydrophone was in the range of 2.5 to 3.0, which is higher than the average value of Kt of 1.6 for a fillet weld performed under normal conditions.


(3) Chemical composition and mechanical properties of materials
The chemical composition of the materials was found to be within the specified limits. A comparison of the mechanical properties between the specification and the test results for the fractured materials is shown in Table 2. The yield strength of the D6 bracing in the longitudinal direction is slightly lower than the specified minimum values. In case of the hydrophone, the Charpy impact energy is lower than the required val
ue of 39 J at -40 C. Moreover, the reduction of area of the hydrophone for the through-thickness direction is markedly reduced because of the large amount of weld inclusions.


(1) Although the D6 bracing was one of primary components of the platform, little attention was given to the installation of the hydrophone into the bracing. Hence, a crack with a length of about 70 mm was introduced in the fillet weld around the hydrophone, before the D6 bracing was painted.

(2) Fatigue cracks propagated from two initiation sites near the fillet weld of the hydrophone in the direction circumferential to the D6 bracing at the early stage of the life of the platform.

(3) The five other bracings connected to the column D broke off due to overload, and the column D was separated from the platform. Consequently, the platform became unbalanced and capsized

(4) Inspection of the D6 bracing had not been carried out.


This is a partial report found on the web and it enpahasizes that all welds should be considered critical.

D
ate August 10, 2001. Revised Nov 20

 

Vist all of Eds MIG and Flux cored programs.

 

 

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