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 Post subject: Re: From the TRAIN News Blog (Re: New Locomotive Boiler Code
PostPosted: Fri Mar 03, 2017 5:38 pm 

Joined: Sun Aug 22, 2004 7:19 am
Posts: 5262
Location: southeastern USA
We don't know if hundreds of bolts were done all poorly. This is just one.

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 Post subject: Re: From the TRAIN News Blog (Re: New Locomotive Boiler Code
PostPosted: Fri Mar 03, 2017 6:47 pm 

Joined: Tue Sep 14, 2004 7:52 am
Posts: 1251
Location: Strasburg, PA
Lincoln Penn wrote:
This is why you NEVER get your welding done by the enthusiastic guy who took night courses in auto body work at the local community college, and is ready and anxious with his Harbor Freight wire welder. This is a job for highly skilled and experienced pressure vessel welders, backed up by sound engineering and properly made parts.

People who make their living building or working on pressure vessels in steam power plants, refineries, chemical process plants, etc. don't come cheap, but they also don't use your job as their learning experience. Enthusiasm is no substitute for experience and sound judgement.

People at this level know a great deal about proper fit-up, properly machined parts, fit tolerances, pre-heat, proper rod choice and care, proper materials, and they tend to be fast. They are used to welding in all sorts of odd configurations, be it hanging upside down or whatever is needed to do the job right.

Proper procedures will specify the root pass and all other passes. And there will be pauses to verify the work as it proceeds.

Re: The photo above. If photos could be taken at this stage, they should have been taken as the work was progressing. Had that been the case, this would have been caught and corrected before hundreds of bolts were done, all poorly.

The photo I posted above is of the water side of the crown sheet of a boiler that was built new to the ASME code by a well known major boiler maker circa 1970. Literally every bolt that can be seen (several dozen at least, it's too small to climb into) is of this quality. There is no reason to believe that these are not the original crown bolts in this boiler.

The photo below is of a bolt and piece of sheet we cut out of the same boiler. You are looking at the water side of the outside side sheet, lightly glass beaded at the joint. There is no reason to expect that the bolt is not original to the boiler. I am at a loss to explain what the marks on the side of the bolt that look like torch scars are.

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I submit that the vast majority of full pen bolts in service today look like these two on the water side. The code may call for full penetration, but what you get from a tired welder (or one that needs to take a dump, or is thinking about his girl friend) isn't going to be perfection on every bolt. I am not inclined to trust "full pen" welded bolts any father than I can throw #90.

Lincoln Penn, you may want to edit your post praising the quality work done by professionals. Some yes, but certainly not all.

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 Post subject: Re: From the TRAIN News Blog (Re: New Locomotive Boiler Code
PostPosted: Fri Mar 03, 2017 6:59 pm 

Joined: Wed Jan 28, 2009 4:30 pm
Posts: 130
This would appear to be a poor job of welding and certainly not up to the parameters of the code. That said, who is to blame? It occurs to me that the weld inspector wasn't inspecting very well. If this boiler has a stamp then more blame belongs to the inspector. If a welder gets away with a poorly executed job due to poor oversight then he (or she) will continue to perform at that level. Just saying that boiler construction is a team effort and all must work to a high standard.

CCdW


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 Post subject: Re: From the TRAIN News Blog (Re: New Locomotive Boiler Code
PostPosted: Fri Mar 03, 2017 11:24 pm 

Joined: Tue Aug 24, 2004 10:34 pm
Posts: 620
Pretty scary looking. Recall seeing cut out inner sheets on C&NW #1385 that had a similar look. The weld side looked fine, but the inner side had very little penetration. The weld was an old C&NW repair on Engineers side sheets down by the front corner. You would never of suspected it. Was a welder back then and it scared me to think that anybody thought it was good enough. Stayed or not. The weld I am talking about was a longitudinal patch, not the staybolts. But the lack of penetration was very similar, but probably worse. This was found back in early 1970s when the fitter put his chipping hammer through the sheet they were so thin. Sorry to ramble so. But the lack of penetration on the pictures above reminded me of that. Wished we would of kept that pc of cutout side sheet to illustrate how a reasonably good looking repair was deceiving. Regards, John.


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 Post subject: Re: From the TRAIN News Blog (Re: New Locomotive Boiler Code
PostPosted: Sat Mar 04, 2017 9:41 am 

Joined: Sun Aug 22, 2004 7:19 am
Posts: 5262
Location: southeastern USA
OK, so we're all in agreement that very good welders who know how to weld should weld on pressure vessels. Full penetration means full penetration. Fillet welded stays can create corrosion issues after some time in service and must be watched carefully.

Screwed in stays aren't immune either. A locomotive I was responsible for developed a situation in which the side sheets and stays were all good but the threads connecting the two had been progressively disappearing for decades. All invisible, and until caulking or seal welding no longer held out for long completely unknown. The solution in this case was trepanning out around the stays and sheets and welding in full penetration by a ASME shop's certified welder. Eventually she was shut down for overhaul and the stays were replaced years later. I wasn't present to see that process.

Given a choice between 1.5 intact threads and 90% penetration by a less skilled welder, I'll take the 90%.

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"Techies never minded eating bits and jots of their work. They were grit and grease inside and out and could turn a pile of junk into a magical kingdom."

Andrea Hairston


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 Post subject: Re: From the TRAIN News Blog (Re: New Locomotive Boiler Code
PostPosted: Wed Oct 11, 2017 12:47 am 

Joined: Wed Aug 25, 2004 11:16 am
Posts: 574
I understand the ASME boiler committee is meeting in Phoenix on October 30th. Does anyone have any information as to the agenda or even if the meeting will actually take place?

Thanks

Robby Peartree


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 Post subject: Re: From the TRAIN News Blog (Re: New Locomotive Boiler Code
PostPosted: Wed Oct 11, 2017 10:55 am 

Joined: Mon Mar 14, 2011 6:45 pm
Posts: 71
Robby Peartree wrote:
I understand the ASME boiler committee is meeting in Phoenix on October 30th. Does anyone have any information as to the agenda or even if the meeting will actually take place?


ASME Boiler Code Week is October 29 - November 3, 2017 at the Point Hilton Squaw Peak Resort in Phoenix, Arizona. Subgroup Locomotive Boilers is meeting on Monday, October 30. This meeting usually starts at 8am and runs as long as it takes to get through the agenda. The BPV I main committee meeting will be on Thursday, November 2 at 8am and usually runs to about 1pm. More information can be found at ASME.org.


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