Weld defects

By pipewelder_1999 (****)

Date 02-07-2004 02:11

Heres My opininon,

Smaller diameters take less time to complete but build up heat faster and with some materials it can be a pain. Smaller diameters are generally thinner. Since the size of allowable discontinuites is a percentage of the wall thickness, the allowable discontinuities must be smaller for thinner materials. The smaller diameters requirer faster changes in rod angles during welding, but you don't have to go very far.

Larger diameters require more passes which increases the chances for lack of fusion. Usually no LOF is permitted regardless of wall thickness. Larger diameters are sometimes more difficult to prep and fitup depending on tools so misalignment due to out of round conditions can make the root pass more challenging.

AS with anything its a matter of preference. I have made plenty of bad welds in both. I like any that are fitup and ready to weld ! The more the merrier. I haven't been on a job with enough of both small and large to do a comparison but I think the larger pipe sizes are easier. I have been on jobs where peple bragged about having "Heavy Wall" certs. A good look at the allowable porosity charts in ASME Sec I would maybe make some rethink what they are bragging about.

Regardless of what size/shape etc, it's not a skill that can be easily learned without a geat deal of practice and effort.

Have a nice day

Gerald Austin
http://www.weldinginspectionsvcs.com

By JTMcC

Date 02-07-2004 03:54

Given my druthers, I'll weld on 36" anyday over 3/4".

JTMcC.

By pipewelder_1999 (****)

Date 02-07-2004 04:20

I like them 2" .250 wall tubes myself. But that big stuff is nice too. I kinda like those welds that need to be welded!

By ssbn727 (*****)

Date 02-07-2004 14:56

Hey Guys!
This may sound like "Crocodile Dundee" but, welding together two Trident submarine hull sections together in the 5G position with no rolling - now that's a pipe!!! Absolutely no discontinuities allowed and 100% RT and UT on these joints... Talk about the pressure these joints had to withstand even though it was mostly external!!!
I do miss the challenge and competition back when I was in shape enough to weld those boiler tubes or those superheater tubes!!!
Repairing or welding piping on those submarines with mirrors and all were no joke either but the challenge of it instilled alot pride in me knowing back then that I was able to accomplish those tasks successfully...
Made you think about who was in charge of building the subs back then when there was always more than one line or structural component that was not installed under more favorable conditions where the fitters and welders had better access to the locations of the joints!!!
"Hangerbangers" did'nt have it any better when they had to install alot of the pipe or tube hangers after everything else was installed beforehand or to repair the ones that were'nt acceptable because of one thing or another... Mirror welding sure kept you on your toes to say the least!!!
I'll take those larger diameter pipes anyday of the week these days!!!

Respectfully,
SSBN727 Run Silent... Run Deep!!!

By pipewelder_1999 (****)

Date 02-08-2004 00:22

I went on a tour of a plant in Alabama that made hull sections years ago. The guy giving the tour was stressing how difficult it was to make some of the structural welds fabricating the individual hull sections. I was thinking "Yeah, you shoud try cutting out an HPD trap manifold with a wafer disk in a mirror without nicking the pipe in the socket(bighunka steel) and then welding it back in! (For $4.00 per hour or so)"

Things look different after a couple of Turbines, Turbine Generators and associated electrical, piping components are installed.

I haven't welded any of the hull sections together but I don't think is is the same level of welding as all those pipes stuffed in that tube :)

Do they still use 1688 for submarine hulls? I thought there were some discontinuities allowed. I got into QC because of inspector insisting on completely "clean" film for piping. As I read the codes I noticed that wasn't what was required. Needless to say I made many friends in 93A.

I do miss those days. I'd hate to have to crawl around one of them babies now to make a weld after working a full shift and standing a midwatch. I'm pretty sure these fat rolls would hang alot.

Sorry to stray from the topic but sometimes you have to re-live those "glory days"

GA

By ssbn727 (*****)

Date 02-08-2004 20:59

Hi Pipewelder1999!
The hull sections on the older submarines were made of different grades of high tensile steel that varied as the technology in steelmaking advanced... 2" to 4" HY-80, HY-100 steel was used on the 688's and theTridents for the pressure hull itself but this was'nt the first time these grades were used.
The superstructures, most of the conning tower and the majority of the structure that made up the ballast tanks were comprised of a combination of HY-80, HY-100 and High Tensile Steel...
The hull sections we worked (Los Angeles and Ohio class) on were fabricated @ Quonset Point, RI.
For the Seawolf and Virginia class submarines, the hull sections are still being fabricated @ Quonset Point but as I have been informed, there is alot more modular assembly going on - meaning that they're packing inside more and more components, structures and piping to these hull sections in order to save more time in final assembly at the shipyards (Electric Boat & Newport News) they're headed to... I believe they're also using a different type of metal for the hull sections...
As far as the piping and tubing was concerned - miles and miles of various grades including: stainless, CuNi, NiCu, inconel, hastelloy, HTS and HY-80 were used...
Nowadays they're using Ti piping components to replace most of the Cu Ni piping because of the extended service life regarding seawater use...
There are other metal alloys being used but, I do'nt think it's appropriate to reveal these in a public forum due to the classified nature of their use so forgive me for not mentioning them... I'll just add that there was a variety of tubing and pipe sizes used also and most of the joints were groove welds with consumable inserts although, there also were alot of socket joints too...
If I remember correctly, most - if not all of brazed joints were done by the qualified pipefitters themselves...
After the "Thresher" and "Scorpion" accidents, Rear Admiral Hymie Rickover (Father of the US nuclear navy) got real tough with respect to QC on the weldments and any other joints on any of the variety of components that made up a nuclear powered submarine. This of course included the welds that joined the hull sections together so, to answer your question as to whether or not some dicontinuities were allowed - the answer is emphatically a resounding NO!!! Think about it Gerald...
Would you want to go down (underwater) to operate in depths exceeding 1500 ft. (they go alot further down than 1500 ft.) knowing that some discontinuities were allowed in the welds that held the pressure hull together? I did'nt think so! I know I would'nt and I've been down that deep underwater in more than one submarine!!!
The submarines I worked on while I was in the USN were older class subs (mostly FBM's or otherwise known as "boomers" but also the newer fast attacks otherwise known as "hunter-killers") were also subjected to the same QC/QA standards that were implemented during the construction of the Los Angeles (fast attack) and Ohio (super-boomers) class submarines that were built back in the late seventies - early eighties...
We used alot of mirrors back then also (maybe that's why I've had all the bad luck in life so far) and we also did alot of stuff inside very similar to what you describe, so the level of difficulty at times was very high.
Even though the level of difficulty was'nt the same when one welded the hull sections together; The quality and consistency of those welds had to be just about perfect! In other words, only the best were allowed to weld those sections together!!!
Everything that was'nt subjected to the level of pressure coming from the outside of the submarine (in other words inside) could be reworked or even replaced but, not when it came to any of the components subjected to the extreme pressures of +1500 ft. of seawater so, one had to focus on quality rather than quantity because these weldments required that the 1st class welders have less than an overall 2% rejection rate through out their employment @ EB prior to being assigned welding any of the pressure vessels that made up a submarine and pass a series of qualification tests that required zero discontinuities in order to pass then be allowed to work side by side someone that already had experience plus the stats to train the "newbie" on how to weld these joints properly... I'm not going to discuss any further on how we went about welding the hull sections together but, I will say that there was alot more than just welding skills required to successfully complete these joints to the level of quality they were subjected to meet and exceed... Not to say that any of the joints inside were of less quality as far as the welds were concerned but, think about it for a minute; a 2" diameter pipe has much less length of weld deposited than an over 40' diameter hull section (the hull sections are'nt cylindrical - they're more elliptical in shape so they're really not like pipe)...
When the submarine reaches a certain depth, the shape of the hull changes due to the increase in external pressure at the top and the bottom of the hull which in turn changes from an elliptical to a cylindrical shape. The allowance for this is designed into all of the internal components including all of the structural and piping components...
Btw, all of the pipe welded joints that were welded inside the submarines had to be performed using the GTAW process period!
However, there were other processes used in the pipe shops prior to being installed in the submarines. Alot of mirror welding those joints in the submarines!!!

Respectfully,
SSBN727 Run Silent... Run Deep!!!

By - Date 02-09-2004 00:50

Hate to be nitpicky about terminology, but having worked on Trident subs and therefore being familiar with the standards involved I know that "discontinuities" are allowed in welds up to the limit of their type, size, and distribution. Once these limits are exceeded, they are now called "defects", and are not accepted.
On this point I agree with you. They are NOT accepted. I worked with a very professional group of people, and the quality of both workmanship and inspection/examination was such that this statement can be made with confidence.
Mankenberg

By ssbn727 (*****)

Date 02-10-2004 16:27

Hi Kip!
You worked in "Rotten Groton' also? Small world is'nt it?
Maybe I was incorrect in the terminology regarding the hull penetrations because I was going by what was told to me as to what was required for the joining of the hull sections... I was'nt inspecting them so, you would know about that better than myself.
I do know the difference between a discontinuity and a defect and how they are determined. I'm just going by what I was told...
I do remember repairing lengths of welds on a variety of hull penetrations and section joints that were rejected also and the inspectors were very adamant about letting us (the welders) know that they did'nt want to see anything at all show up in the RT film...
I guess they did that in order for us to do better... So they lied to me huh? Oh well - I do'nt mind if it meant for us to weld the best we could!!!
Btw, what shift did you work when you were there?
I worked second shift mostly but, I also worked third for awhile on alot of the 688's that were in the "wet docks" when they had to get them out of the yard ASAP!
However, most of my time was spent working on the first three Tridents in all of the compartments and it was always a fun place to work!!!
Do you remember "Elfie's" or the "El Bolero"? How about "American Chop Suey"? Anywho, it's good to talk to someone that knows about the quality of workmanship that was performed at EB!!!

Respectfully,
SSBN727 Run Silent... Run Deep!!!

By - Date 02-10-2004 23:40

Actually, and believe it or not, I worked in Minneapolis (FMC) on the missile tubes that of course also form part of the hull. EB had some reps there, and though I did not interface with them extensively, from what I saw they were very active and very keen. I have no doubt that things were/are done right in Groton.
I was the night shift NDT lead man, at the time, on the missile tubes.
Mankenberg

By ssbn727 (*****)

Date 02-11-2004 18:08

Hi Kip!
I believe you!
I welded quite a few of those missile tubes also!
Tons of weld metal deposited to join them to the hull sections and more more pounds than I care to remember to connect them to the decks via gussets & vibration isolators; not to mention all of the piping, pipe hangers, control panels and machinery associated with each of those missile tubes... I also spent some time building up a few of those tubes that were "over"-bored by the the machinists for placement of the rings that were used to ensure a water tight seal when the hatches were shut! What a fiasco! Thank god this only happened on the first two submarines and only on a few of the tubes!!!
The machinists (@EB) mistakes resulted in the delay of installing the superstructures to the subs...
Anywho, It's nice to converse with someone that had an important part in fabricating those tubes!

Respectfully,
SSBN727 Run Silent... Run Deep!!!

By pipewelder_1999 (****)

Date 02-09-2004 01:44

I was never involved in the building but spent numerous hours replacing valves in MS,AS, ASW,HPD, CHV, MC and a few other designations. Our hull work was limited to Bulkhead 119 cutouts for 300 KW rewinds. I remember the the acceptance criteria being much more stringent than what I work with now but a certain number of rounded indications were allowed of certain sizes from what I remember.

The boomers I worked on were HY80 on pressure hull componenets and HTS on other parts of the structure. Never worked on any HY 100 but I can imagine it was a pain on small diameter penetrations.

The CuNi was one of the most dreaded materials we had to work with when it was a butt joint. It sure was a pain to get a purge with a good dewpoint.

I remember a few pieces of film having discontinuities measured to see if they were "defects" and I was pretty sure that was on HY-80 but I may be mistaken. Otherwise, that of course would make the acceptance criteria section of the code VERY short. I may be mistaken regarding how clean an RT had to be for hulls but I spent a good bit of time reading MS 1688 and 1689. I don't think those codes are used any more.

It was my understanding that the one of the submarines lost was related to a piping component failue (Brazed Seawater Line) and subsequent equipment failures but I think the investigation was not completely conclusive.

I agree that the quality required and service conditions are extreme. The quality of mechanical, welded and brazed joints should match those requirements but I would think some discontinuities are allowed but of course I could be in error.

One of the commands I was at sent the welders to captains mast with the threat of NJP if you had more than 3 rejects in a 30 day period including welder quals. I was sent to an interview with the repair officer or my division offivcer ? after making numerous acceptable 1/2" Schedule 80 butt joints on various boats in glovebags with a mirror and then when I did one in the shop welding extensions on a valve it was rejected for convexity less than 1/16" of an inch. They truly though I did it on purpose.

I regularly stand next to pressure vessels that are allowed to have discontinuities (Not defects) with a good deal of faith based on the skilled craftsman, inspectors and invaluable engineers that designed and put them together. I feel much safer on that than I did on the last ship I was on (Riveted Hull and Wooden Decks!).

We GTAW welded all roots but I think that one of the reasons for that is to reduce foriegn material in the systems. I have never come across any data that indicates GTAW is any better than SMAW but it does have some advantages for the welder. Mirror welding with stick sure is a pain to keep the mirror clean. Of course I'm not an engineer so I am only guessing.

I worked on boomers when in Scotland and fast attacks in New London. If I remember right the fast attacks were 593 (Thresher) class.

Did you have anyinfo on the Collins class Austrailian Sub that ruptured a pipe ? I think it was Austrailian but I may be wrong.

Anyway, have a good day and thanks for the discussion

G Austin

By ssbn727 (*****)

Date 02-11-2004 19:03

Hi Pipewelder1999!
Small world!
As a welder @ EB we were'nt given complete access to all of the inspection criteria or the standards that the inspectors had to work from during the time of my employment there so, both you and Kip were privvy to more info than we were. I suspect that things have changed since for the better... We just went by what the welding foremen, supervisors and inspectors told us so both of you are probably correct!
I know one thing for sure is that very few - if any indications were found on the hull section welds for a given submarine.

Anywho, to answer your question about that Australian conventional submarine of Swedish design - built in Australia, no I have'nt heard of a pipe rupturing but, I did read about how all six of the Collins class subs had some extensive re-fit work performed because of excessive noise and a multitude of other problems which have since been supposedly resolved... General Dynamics - Electric Boat Division was or is supposed to be in the process of providing service support and upgrades to the Australian Navy but, I heard there were some delays because of national security issues regarding the access of technology with respect to the Swedish designer (Kockums) that was or is partially owned by a German firm that also provides work and technical expertise to not so friendly countries. I do'nt know the specifics but this is what I read.
The Royal Navy is investigating an advanced concepts design by BAE that has a rather unique foward sonar configuration that looks like a bill on a platypus in case you're interested...

The New London area has changed so much and not for the better since you or I were last there basically because of the Foxwoods casino and the increase in crime as a result but, I still go out there every once in awhile to visit some old friends of mine that still live there... Gales Ferry is still humming though!!!

Anywho, good talking to someone else that knows their way around our submarines!!! USN - Second to NONE!!!

Respectfully,
SSBN727 Run Silent... Run Deep!!!

By pipewelder_1999 (****)

Date 02-12-2004 03:05

I drove through New London a couple of years ago and state pier had changed quite a bit. It brought back some good memeories though. I hop to make it back to Scotland some day and look around as a civilian.

The 30 weeks of welding school I went through in the Navy actually included quite a few weeks of code study. We had MS 248, 278, 1688, NS 250-1500 and NSTM 389-0317(Seal Weld Manual) . We actually had to carry these books back and forth if I remember right.

I never thought I'd need it till I ran into a few inspectors that though if it ain't white it ain't right. I studied the codes and found out what was and wasn't acceptable and that actually got my interest in QA/QC. A couple of film readers would often reject a guys 1st qualification plates or pipes when they arrived. I was qual P.O. and started paying closer attention to the film and questioning the film readers. They didn't like it when I explained that a 1/64" diameter rounded indication wasn't rejectable. I would get referred to the statement that "this is the minimum requirement for repair of U.S. Navy......." I then explained the USN "Waste Fraud and Abuse Policy" and things seemed to workout a little better.

I'm sure things have changed now. I'd like to know what its like for an active duty Nuc Welder now.

Have a good day

GA

By mstrmnipulator Date 03-06-2004 02:36

There are no more "nuc" welders in the navy. Our '4956' nec was taken away in '96. I think it was because there were so many so called 'nucs' who had spent their first few tours on conventional ships and had never done any nuc repair and then showed up somewhere like TRF Bangor or TRF Kings Bay or at one of the prototypes in NY or ID. and proved that they could neither do detailed welding in restrictions nor work efficiently from a CWP. Its a shame because there were some of us who had worked their entire time as nuc welders and were quite good at it. I went from C-1 to the Orion then to the Gompers then on to TRF Bangor(lots of experience there) and finally the Dixon ...then BAM! my NEC was gone...I went on to a DD and finally a 'port ops' command. Oh well...I guess the only way I'll see another QA-6 is if I go to work for PSNS!

By pipewelder_1999 (****)

Date 03-06-2004 03:12

I figured it was coming. It was so much more efficient to have a shipyard spend 5 shifts replacing the same CHV we would do in 3:)

I never met any 56's that hadn't welded(Other than fresh out of school) but I could see the problem with one showing up at a site and not having any experience.

Thanks for the info.

G Austin, USS Hunley AS 31 83-86, USS Fulton 86-88

By MBSims

Date 03-06-2004 04:32

Gerald,

Luckily I spent my whole tour in shop 26 on the Proteus and the Dixon after finishing C school. It seemed that me and one other welder got most of the tough jobs like CHV-19 and 21, XC-19, and the CuNi seawater valve body repairs. I got two 1/2" Monel welds one time that I must have done 10 mockup welds on before the job and they shot clean the first time. I was sweating bullets on those welds because of how easy it is to get crater pits on the nickel alloys. I don't miss the days of 12 on/12 off shiftwork though for the hot jobs and drydock work, but I have to say it was good experience and would not trade it for anything.

I did meet a few 56's that did little or no welding after school. They usually got sent to P&E, NSRO or RadCon right out of school and seemed to get trapped there. It was a tough break because they couldn't get the experience they needed to utilize that C school training.

By pipewelder_1999 (****)

Date 03-06-2004 14:40

Thats about what we did. We also did a few of the HPD 171's (Secondaray Side but still NUC). We did a few CRDM mods.

On the 1/2" joints, I did quite a few on the boats in place with radcon and later I had to do one in the shop. It shot bad and they wanted to put me on report. We had a period of time where the PMA and RO decided that 3 bad welds a months was unacceptable and you may be subject to NJP.

We did quite a bit of the 12 on 12 off with 3 section duty. All duty nights were TC. Boy was it hard to get me to turn down overtime after I got out. THEY ACTUALLY PAID EXTRA!

When I ent on my twoweeks of trainig on the Cable when I got in the reerves Inoticed alot less work being done in the weld shop than in my other commands. Many didn't know what TC was.

I'll be honest though, I think the HPD Trap manifolds were greater skill builders than most of the NUC work. Except for hand prepping a bevel in a glovebag with +/- 2-1/2" degress .

By mstrmnipulator Date 03-06-2004 06:27

Hmmm...the Hunley? I knew of a few that didn't do much nuc welding there...I won't mention their names in the public forum though...one was there when you were though...got there just as you were leaving probably...like in sept. 85...email me and I'll let you know:) Alot of the 56's welded, yes, but not many on actual nuc jobs. There were only so many of those at regular IMA's that could be done or actually needed to be done. I can remember praying for a 'sat' bluecheck for leakby on some of those CUNI ones! YUK!!! We use to say it ran like toothpaste! The canopy seals weren't bad on the job....it was getting the qual through that cut & etch...especially the NICU TA-2!
I found this site with a search for "navy 4956 welders". I was originally trying to find out if there was a specific site for those of us who are still welding and passionate about the craft. Anyone know of such a site, club or organization? Thanks.

By pipewelder_1999 (****)

Date 03-06-2004 14:31

We started a 38N shop and many of us welded out of there and some just stuck with HPD's. We did a couple of SGI's and had a regular shipalt on a CHV on every boat. We also did some MC lines which was one of the items I referred to regarding the number of shifts for the shipyard vs 26A

We stayed pretty busy with Nuc work but all of the 56's did non nuc work. Some of the 56's only stick welded other than keeping up quals.

Those TA 2s were tough. NICU and CUNI socket weld quals were tough too. You just didn't seem to get much penetration beyond the root. I had been known to run a ball burr around the joint prior to welding the root. BAD WELDER!

Gaustin

By pipewelder_1999 (****)

Date 03-06-2004 14:44

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