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NOVEMBER 20082

While discussing the possibilities of ajoint talk with him, he asked, “Why don’tyou come down here to Miami and par-ticipate in our Hydroweld wet weldingtraining program?” I agreed right away.

As a welding engineer trained in Ger-many, I went through an apprenticeshipprogram and I learned how to weld. So, Ibelieved, it shouldn’t be too difficult forme to weld underwater. On top of this,working also as a commercial diver Ithought it should really be a walk in thepark. Having dived in all kinds of envi-ronments, from potable water to sewage,I viewed this opportunity as just takingmy welding skills to a familiar underwa-ter environment.

What Miami Diver Dedicates Itself To

A member of the Subsea Solutions Al-liance, Miami Diver specializes in under-water ship services offering repair andmaintenance solutions worldwide.Trained service personnel with specializedequipment perform maintenance andhighly specialized repairs underwater onpredominantly floating structures any-where in the world. These structures in-clude merchant, naval, and passenger ves-sels, semisubmersibles, Floating Produc-

tion, Storage and Offloading (FPSO)/Floating Storage and Offloading unit(FSO), and barges.

In order to retain their position as aworld leader in the field of underwatership services, the company recognizes theneed to maintain a highly skilled, compe-tent workforce. It has a policy to ensureits personnel are provided with the latest,

UWE ASCHEMEIER (uwaschemeier@terracon.com) is a senior welding engineerand commercial diver for H. C. Nutting, aTerracon company, Cincinnati, Ohio, and

also provides consultation, engineering,and inspection services. To find out moreabout its diving capabilities, contact Brad

Walden at (513) 321-5816.

Underwater (Wet)Welder Training from an Engineer’sProspectiveThis first-hand account of an intensive ten-day programdetails the skills learned ranging from theoreticalpreparation to testing of welds made underwater

BY UWE ASCHEMEIER

Fig. 1 — Macro of a multipass wet weldedfillet weld.

A diver makes a fillet weld with the shieldedmetal arc process.

My adventures in underwater wet welding began with a phone call. I hadbeen asked to find a speaker to talk about underwater welding for a Ger-man Welding Society (DVS) seminar, so I called Kevin Peters, presidentof Miami Diver, Inc., Miami, Fla.

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state-of-the-art training opportunities, in-cluding specialist training in underwatershaft seal replacement, propeller straight-ening, and underwater welding.

The Basics of EducatingWelder Divers

The modular courses offered byHydroweld last for ten days and are in-tended to train commercial divers to thestandard required to pass a Welder Per-formance Qualification (WPQ) to AWSD3.6M:1999, Specification for UnderwaterWelding, to Class ‘B’ welds and, where ap-plicable, to Miami Diver Class ‘A’ proce-dures. The WPQ is witnessed by LloydsRegister (LR), which also issues the cer-tification. Lloyds Register is a major clas-sification society, and certification issuedby them is generally accepted by otherclassification societies worldwide.

The course objective is to train welderdivers who are serious about pursuing acareer in wet welding or who wish to im-prove on their current wet welding capa-bilities and gain a recognized wet weldingqualification.

Established in 1987, in West Midlands,Great Britain, Hydroweld develops wetwelding consumables, processes, andtechniques, and training programs as wellas consultancy, personnel, and serviceswith the aim of significantly improving thequality and reputation of wet welding. Themodular nature of the courses is in recog-nition of the time required to develop thewet welding skills in each position and/orjoint configuration. With wet welding pre-dominantly completed in the vertical oroverhead position, modules one and twoconcentrate on these positions and leadon to more difficult positions such as 5Fpipe to plate and further to buttjoint/groove welds.

The courses systematically guide stu-dents through various tasks designed toimprove their wet welding skills and pro-vide a sound foundation for subsequenttasks. With the philosophy that ‘practicemakes perfect’ and with some guidance,the courses have a realistic time frame inorder for even some of the less naturallycapable students to succeed. However, itis not an attendance course and studentsare subject to failure should they not meetthe standard. Student numbers are lim-ited to ensure maximum water time isachieved.

While no previous underwater weld-ing experience is necessary, an under-standing of topside welding, both theoret-ical and practical, is a significant advan-

tage to any student wishing to enroll. Thisknowledge helps the student progressmore rapidly though the courses and in-creases the likelihood of satisfactorilycompleting the welder performancecoupons to the standard required by AWSD3.6M:1999.

The courses are open to both individ-ual commercial divers and diving contrac-tors. Commercial diving contractors whowish to sponsor a number of welder diverson a project-specific wet welding courseare welcome to discuss their individual re-quirements. These requirements may alsoinclude the development and qualifica-tion of welding procedures in addition tothe qualification of wet welders to the spe-cific welding procedures.

Identifying Four WeldClasses

The AWS D3.6, Specification for Un-derwater Welding, was first published in1983 to establish a standard reflectingstate-of-the-art technology relative to un-derwater welding and to provide thosewith a requirement for underwater weld-ing a choice of weld quality, on a fitness-for-purpose basis. As with all AWS/ANSIdocuments, the specification is revised ona regular basis (approximately every fiveyears) to keep up with modern technol-ogy. The AWS D3.6 specification sets outfour classes of welds identified as A, B, C,or O. These classes are broadly definedas follows:

• Class ‘A’ welds, which are intendedto be comparable with above-water weldsby virtue of specifying comparable prop-erties and testing requirements.

• Class ‘B’ welds, which are intendedfor less critical applications where lowerductility, greater porosity, and larger dis-continuities can be tolerated.

• Class ‘C’ welds, which are intendedfor applications where load bearing is nota primary consideration and that satisfylesser requirements than Class A, B,and O.

• Class ‘O’ welds, which must alsomeet the requirements of another code orspecification.

The AWS D3.6 specification details alist of essential variables, which are ad-dressed and recorded during the develop-ment of the welding procedures. Thesevariables take into consideration the jointconfiguration, base metal, filler metal, po-sition, weldment temperature, electricalcharacteristics, technique, and environ-ment — Fig. 1. The specification also de-tails the nondestructive and destructive

Fig. 2 — Hydroweld’s 35,000-gal trainingtank.

Fig. 3 — Arrangement of the communica-tion station.

Fig. 4 — Michael A. Pett watching the au-thor through the observation window.

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NOVEMBER 20084

testing criterion for each class of weld.While Class ‘B’ and ‘C’ welds are easilyachieved with the wet welding process, theproduction of Class ‘A’ welds has not, untilrecently, been an option because of thedifficulties in meeting all of the mechani-cal and visual property requirements de-tailed in the specification.

Essential to the production of theseClass ‘A’ surface quality welds is the weld-ing consumable. Many diving contractorscarry out wet welding using off-the-shelfwelding electrodes originally designed forsurface welding. These electrodes are ei-ther taped up or dipped in paint, varnish,or other such coatings in an attempt to in-sulate and waterproof them. However,while these electrodes may perform wellon the surface, when used underwater theenvironmental conditions can signifi-cantly alter the welding characteristics andthe mechanical properties of the com-pleted weld.

Wet welding is often seen as a poor re-lation of conventional dry welding withsome justification. Although wet weldingcan produce results to Class ‘A’ surfacequality welds, the process is discreditedby diving contractors unfamiliar with thetechnology taking on projects, includingship repairs, that frequently result in un-acceptable weld defects and, in somecases, weld failure. This failure or unac-ceptability is then seen by clients who thenare subsequently reluctant to accept wetwelding for anything other than noncriti-cal, temporary repairs.

Advantages of Underwater Wet Welding

It is with the above in mind that we canturn to the importance of wet welder train-ing and certification. In today’s world withan ever-increasing requirement for trace-ability, quality assurance, and quality con-trol, it should be possible to virtually elim-inate or at least minimize the risk of un-acceptable wet welding. In the offshoreoil and gas industry, generally there is al-ways a requirement for proof of compe-tency, training, and qualification, yet inthe shipping industry it is often a case ofwhoever is available at the time the workneeds to be performed.

Underwater wet welding for repairinglarge structures submerged in the sea isoften much more economical than the al-ternative of building a hyperbaric contain-ment structure around the weld locationsin order to perform welding in a dry environment.

The wet welding process is the mostversatile, cost effective, and widely usedmethod of repairing and modifying steelstructures underwater. The process isused extensively in the offshore oil andgas industry, for applications such as re-placement and modifications to structuralmembers, strengthening project and newinstallations. Most of this wet welding issubject to class approval and generally re-quires the qualification of wet weldingprocedures and welder qualifications. Incivil engineering, permanent repairs andstrengthening of structural piles onbridges and jetties as well as dock wallsare also completed using the wet weldingprocess.

Day-by-Day Details of the Program

The class took place in Miami in Feb-ruary at the corporate office of MiamiDiver. Hydroweld shares part of the facil-

ities: a classroom, shop area to preparetest specimens, and the heart of the train-ing facility, a 35,000-gal training tank —Fig. 2. The 20-ft-diameter tank providesthree workstations, allowing three diversto weld at one time. The instructor canwatch and critique each welder throughan observation window of about 1 ft in di-ameter at each welding station. He cancommunicate with each welder through ahead set and microphone.

Students learn to master couponpreparation and wet welding in the 3F(vertical fillet weld) position in the con-trolled environment.

The program is scheduled for 10 days.I thought, “Ten days … who needs ten daysto learn how to weld two pieces of steeltogether with a fillet weld in the verticalposition?” After the program was over, Icompletely understood the need for tendays. There were nine wet welders-to-bein the class from such places as the UnitedStates, Canada, and the Caribbean.

The first day we got familiar with thefacility and equipment, and received ex-tensive theoretical training in underwaterwet welding. The instructor, Michael Pett,taught us the theory of welding underwa-ter, including introductions to the equip-ment, safety aspects, and underwaterwelding techniques.

The second day the nine welders ro-tated in groups of three: One groupwelded underwater, one group operatedthe communications stations, and onegroup prepared the weld specimens —Fig. 3. Every two and a half to three hoursthe rotation was switched, which is onereason for the ten days, since each welderonly practices underwater up to threehours per day. Any longer, student con-centration drops off and, in some cases,cold sets in.

The first task was to weld beads onplate — first just stringer beads, then apad across the plate. This relatively sim-ple task enabled students to familiarizethemselves with the setup underwater, todeposit a considerable number of weld-ing electrodes, and provide the instructorwith a guide to the general capability ofeach student.

On the third day, the task was to weldfillet welds 12 in. long on a ¼-in.-thick cru-ciform specimen (see lead photo). Dur-ing my 30 years in the welding field, I havefirmly held to the rule that vertical weld-ing on structural steel is performed in anupward progression. With some excep-tion, such as the root on pipes, sheetmetal, or to repair undercut on welds onstructural steel, you never weld down-ward. I had to learn that it is opposite un-

Fig. 5 — Underwater welding station setup.

Fig. 6 — Location of test specimen on ½-in.-thick fillet weld test plate.

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derwater and that travel speed is differ-ent. When welding downhill topside (asin nonstructural applications), you gener-ally have to weld quickly to be ahead ofthe weld pool; underwater, travel speedis much slower due to the rapid cooling ofthe slag and weld metal. Just about every-thing is more critical and precise under-water — the heat generated by the arc ismore constricted and every movement ofthe electrode, such as a wobble, will beseen in the finished weld. Travel speed iscritical as is electrode angle and bead po-sitioning.

First we learned how to weld the rootpass on the cruciform, which was a bigchallenge for me. It seemed for the firstfew days in the tank I was unable to ac-complish the given task; mastering con-trol over the tip of the electrode was dif-ficult resulting in incomplete side wall fu-sion, cavities in the weld, and burningmore holes than depositing weld metalinto the joint. Initially the amperage for a1⁄8-in.-diameter shielded metal arc welding(SMAW) rod was 150 A.

I continued to practice welding theroot pass with a 1⁄8-in.-diameter rod into¼-in. material. While the other welderswere making progress, I was not.

On the fourth day, those who masteredthe amperage of 150 A and were produc-ing constant acceptable welds had theiramperage increased to 160 A. I was stillproducing holes in my welds though.

On the fifth day, for those who mas-tered the increased root amperage, theystarted to weld a second and third pass. Istill stuck with my root pass.

Pett was very patient with me. He puton his headset with his microphone,watching me the entire time through theobservation window, and never gave upon me.

The sixth day was basically the same asthe other days, increasing the amps onroot and cover passes for those who mas-tered the previous parameters and wereproducing constant acceptable welds. Butnot me. Pett even had a stool in front ofmy observation window at this point —Fig. 4.

The seventh day, Pett took me into thewelding booth where we produced thesamples, and I demonstrated to him thatI can produce a sound specimen in the dry— Fig. 5. We discovered that the problemwas my vision. Since there is limited roomin the diving hat for glasses, we usuallydon’t dive with glasses, but use cheaterlenses on the outside of the hat attachedto the weld lens holder. We decided tojerry-rig my glasses and wear them in thediving hat. Problem solved. When the ro-

tation reached me for welding underwa-ter, I was able to control the pool and toproduce satisfactory root and coverpasses. I felt much better than I had thedays before.

The eighth day I caught up with thedivers using ½-in. cruciform plates and in-creased the amperage for the root pass to175 A and for the cover passes 150 A.

The ninth day we increased the amper-age again, this time to 180 A, and left thecapping runs the same at 150 A.

The tenth day was test day — Figs. 6,7. We had about one hour of practice timein the tank to weld the test specimen ac-cording to AWS D3.6, Fig. 5.8 (½-in. fil-let weld, ½-in.-thick material, 12 in. long).The test was witnessed by Lloyds Regis-ter. After welding the specimen, I cameout of the water and presented it to Pettand the inspector from Lloyds. They did-n’t seem too impressed with my weldingskills. After discussions, they agreed to ac-cept it visually, but the break test resultscaused me to fail due to incomplete rootpenetration. I had to go back in the water.The second run proved to be much moresuccessful. I remembered the tips Pett had

given me the previous days, and I appliedthem during the test. This time the resultswere satisfactory for the visual and breaktest. The macros showed very deep pene-tration with no defects.

Concluding Thoughts

Now I understand why the training isscheduled for ten days. To produce AWSD3.6 Class ‘B’ welds underwater is not aseasy as it seems. It requires the welder toadopt new welding techniques and to bevery patient. The ten days of the coursealso makes sense, since each welder hasonly 2.5 to 3 hours of practice time eachday in the tank.◆

Acknowledgment

As a welding engineer and a commer-cial diver, this was a very challenging andeducational experience. I am very grate-ful for all the help Michael Pett providedme and the invitation from Kevin Petersto be a part of this wonderful opportunity.I hope I will get the call one day to put mynewly acquired skills to work.

Fig. 7 — Diver welding a fillet weld with the shielded metal arc welding process on a ½-in.-thick plate.