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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 06, 2018 7:13 am 

Joined: Sun Aug 22, 2004 8:31 am
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Location: South Carolina
Here’s a current example of a locomotive frame-sized structure that’s fabricated by welding: the frames for Caterpillar’s 797B off-Road mining dump trucks.

From an article at: https://www.airfloat.com/nat-geo-tv-visits-cat-decatur/
Quote:
Components for the 797B are made in six factories across North America. The frame and most of the components are assembled in CAT’s sprawling 350-acre Decatur, Ill., facility.

The frame, considered the backbone of the dump truck, is comprised of nine separate castings forged in Louisiana. Once assembled, the frame stretches 37 feet in length and weighs 61,000 lbs. An astonishing 275 pounds of welding wire are required to stitch the metal skeleton together.


Image

I’m sure the T-1 frame will be longer, but otherwise these truck frames are similar in cross-section and complexity to a cast bed locomotive frame.

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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 06, 2018 8:23 am 

Joined: Tue Jul 17, 2012 5:24 pm
Posts: 42
I saw on Facebook this morning that the Dailey Foundation awarded the T1 Trust $5000 for work on the tender. It looks like plans are in the works for it as well. I hope they at the very least get a coat of paint on it.

It sounds like they are doing brake work to get it ready to move it. I assume up with the PRR 2-10-0? Did I miss that announcement?

https://www.facebook.com/TomEDaileyFoundation/


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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 06, 2018 1:27 pm 

Joined: Thu May 24, 2012 1:37 pm
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Randy, as a peripheral note it's been commented here, perhaps several times, that most of the cast engine beds were done with only two pours (of course with extensive and preheated gating and venting, and experienced knowledge regarding progressive speed of the pour). I had thought prior to learning that that one of the 'secrets' at GSC was having multiple pours with slightly different alloy compositions so that, say, thinner attaching brackets might have more strength, or some areas like pedestal liners might have greater hardness, with reasonable diffusion zones between them by the time slow cooldown and then stress relieving was complete.

This note comes, historically, at a time I believe submerged-arc welding was becoming a known practice, and two years after boiler pressure-vessel seam welding was approved as a practice (it had been experimented with, I believe starting on the D&H, since 1937. At this same time, the Germans had highly advanced the art of 'rotisserie' progressive welding of U-boat components, as adapted by Oliver Bulleid in both the jigging and fabrication of the Leader bogies; I have seen no real evidence that any problem either with the weld quality or with distortions was reported as a cause of failure, even as several fairly substantial refabrications of the suspension were mandated by changes in the "transmission" and the remediation of the initial poor riding of the tested engine.

I see no reason why Baldwin would not have reasonable knowledge of how to make a proper fusion-welded frame, out of reasonable-quality material even under WPB restrictions, at the time of the reported article. By no means does that invalidate Robby's thought that the claim was more for 'publicity' than reflective of an actual engineering priority; in the event, the T1 frames were famously and carefully cast, as were most of the diesel frames for some time afterward, which is where I would certainly expect to see advanced fabrication used at Baldwin's if the techniques were well-known there in 1945.

Remember that there were (and are) techniques other than controlled-atmosphere blanketing to accomplish good fusion welding downhand. And even a large and long frame in a rotisserie jig (with appropriate bob- and counterweighting added or subtracted as fabrication continues) can be made with most of the full-penetration welds executed in near-enough downhand position.

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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 06, 2018 2:05 pm 

Joined: Mon Jan 17, 2005 9:06 pm
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Location: Thomaston & White Plains
I have been told that GSC had a 50% rejection rate for engine bed castings; the rejected casting was simply cut up and "thrown back in the pot" for re-melt. That wouldn't be surprising, and with the material being re-used, not much was wasted besides all the labor involved.

Anyone with more knowledge, please comment or correct!

Howard P.

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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 06, 2018 2:53 pm 

Joined: Sat Aug 21, 2004 10:52 pm
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hi,

It was lucky for the T1 Trust that they found a complete T1 tender.

Doug vV


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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 06, 2018 4:16 pm 

Joined: Sun Aug 22, 2004 1:51 pm
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Location: Baltimore, MD
Dougvv wrote:
It was lucky for the T1 Trust that they found a complete T1 tender.


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Ummmmmmmmmmmmmmm............. no.

The presence of a "Long Haul" PRR 210F75, rescued from Hagerstown by the Wilmington & Western and later sold to the Western NY RHS, custodians of PRR 2-10-0 4483, was long known even before the T1 Trust was formed, so it didn't have to be "found."

Further, although this eliminates the need to replicate eight-wheel tender trucks and a frame, it still requires a great deal of conversion to make it into the T1 PRR 180P84.

Seev previous thread: viewtopic.php?f=1&t=40050&start=30


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 Post subject: Re: PRR T1 Build Update
PostPosted: Thu Feb 08, 2018 10:18 am 

Joined: Mon May 24, 2010 10:22 am
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A History of Welding

http://weldinghistory.org/


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 Post subject: Re: PRR T1 Build Update
PostPosted: Thu Feb 08, 2018 2:22 pm 

Joined: Fri Dec 22, 2017 6:47 pm
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Location: Philadelphia, PA
I would make a correction to the welding reference. For the year 1930, the Budd Company (see also 1912 for E. G. Budd himself) built the Pioneer, not Privateer. It is an airplane, a stainless steel amphibious biplane with fabric covered wings and tail, and is currently displayed in front of the Franklin Institute in Philadelphia.

Also in 1933, Congress authorized 4 submarines for Fiscal Year 1934: USN SS 172-175. SS 172-173 built at Portsmouth Navy Yard (Kittery ME) were riveted while SS 174-175 built at Electric Boat (Groton CT) were welded. All subsequent fleet subs are welded. These boats also introduced diesel-electric propulsion where the electric motors are used on the surface as well as submerged. Power for each boat was 4 Winton 16-201A engines.

As a parallel to the submarines, prototype GG1 4800 of 1934 has a riveted carbody while the production motors have welded carbodies. All have cast frames, though.

The point is that welding science was evolving in the steam era but it would appear that cast frames were state of the art at the time. Even EMC was having trouble selling RR's on welded frames on its shifters in the 1930's.

Phil Mulligan


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 Post subject: Re: PRR T1 Build Update
PostPosted: Thu Feb 08, 2018 4:25 pm 

Joined: Thu May 24, 2012 1:37 pm
Posts: 958
Quote:
"The point is that welding science was evolving in the steam era but it would appear that cast frames were state of the art at the time."


A point to remember is that cast beds offered relatively thick homogeneous sections against bending and distortion. A history of welding that does not have a section explicitly dealing with extremely-thick-section fusion welding (which really began, in my opinion, only with electroslag welding) is really missing the point. Just as welding a 300psi steam pressure vessel is different from welding a submarine hull, even for substantial depth, in relatively cold water, or a largely-nonstructural GG1 shell, a welded frame that did not comprise the permanent stiffness and freedom from 'working joints' of a good cast bed is a very different thing from what EMD calls a welded frame.

In a sense, this provides some support for Robbie Peartree's view that a fabricated version of a T1 frame in 1945 might be materially weaker in some respects than a cast bed equivalent would. I would need to see more detailed drawings of the frame or the components used in it, perhaps involving the equivalent of doubled plate frames to get the penetration zones down to what could give the right mix of cost-effectiveness and weld depth.

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 Post subject: Re: PRR T1 Build Update
PostPosted: Fri Feb 09, 2018 6:18 pm 

Joined: Sat Oct 17, 2015 5:55 pm
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What is the record of welded frame repairs on cast frames? Did railroads ever have a new frame cast to replace a cracked frame, or were welds the standard? I would guess there is a large body of evidence for weld repairs, and those repairs would be rather crude compared to what is planned for the T1.


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 Post subject: Re: PRR T1 Build Update
PostPosted: Mon Feb 12, 2018 11:21 pm 

Joined: Thu May 24, 2012 1:37 pm
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Quote:
What is the record of welded frame repairs on cast frames?"


I don't have firsthand experience with these repairs, but I have read and heard a great deal about them particularly as they were conducted for the P5 and GG1 frames
In general I would expect fusion welding of a cracked cast design to be very different from what is involved with a new-built welded frame' you already have what is probably substantial overbuilding in the structure, and the welding inherently accounts for some of the opening/crack-stress relieving that may have contributed to the cracking in the first place. Much of the supposed reason for the problems was described as 'crystallization' (which may actually be several things related to aging of a cast frame) and the fusion welding only addresses the region of such a crack with the associated HAZ, if anything, making the adjacent situation worse.

I do know that it was discussed in the 1970s that thorough cleaning and beading of GG1 underframes, followed by prolonged reheat and soaking and some welding under controlled atmosphere as necessary, was supposed to redissolve the 'crystallization' and otherwise bring the cast underframes to near-original condition. Problem was that there were better as well as less expensive methods to make a GG1 a 'better' passenger engine.

Quote:
Did railroads ever have a new frame cast to replace a cracked frame, or were welds the standard?


I don't remember offhand a case where a locomotive had its whole cast bed replaced (by GSC) as a consequence of serious cracking that couldn't be patched by fusion welding. I have seen references (some of them, in retrospect, more than a little scary!) about early autogenous fusion welding of bar frames, I believe on ATSF for one. It's orders of magnitude less money, time, and effort to weld up detected cracking, even if careful attention to getting enough 'full penetration' has to be made, than arranging a whole new frame.

A possible exception is the Victorian R class, in Australia -- ISTR something about fairly severe cracking of cast beds in these that required rework or replacement, but I can't find the references properly with the flu.

Quote:
I would guess there is a large body of evidence for weld repairs, and those repairs would be rather crude compared to what is planned for the T1."


That was certainly true right up to the end of 'practical' repairs of cast large frames. It would be interesting to see figures for different kinds of diesel cast truck frames, and current 'best practice' for managing these when they crack.

It is interesting to consider where and how cracking might develop in the composite cast and forged construction anticipated for the T1. What I might note is that the jigging, NDT, and welding equipment needed to work on the frame in proper 'finish' alignment is part of the currently budgeted plan, as is the facility on the mobile support equipment to do lighter versions of frame welding and testing, so even in the unlikely event that cracking unanticipated by the design modeling and stress analysis should occur, it would be easily remediated and not constitute a 'showstopper' failure.

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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 13, 2018 9:33 am 

Joined: Tue Sep 14, 2004 7:52 am
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Location: Strasburg, PA
PMC wrote:
Did railroads ever have a new frame cast to replace a cracked frame, or were welds the standard?

I doubt that ever happened with steam locomotives in that none were in service long enough to "wear out" their cast bed frames (GG1's were around forty years old before frame cracking was noted as being a problem.

I do recall Smith mentioning in One Man's Locomotives about a RR sending a bed frame back to GSC for "straightening" after they "bent" it. I would love to hear the back story on that one.

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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 13, 2018 12:08 pm 

Joined: Sun Aug 22, 2004 12:15 am
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PMC wrote:
Did railroads ever have a new frame cast to replace a cracked frame, or were welds the standard?


I would think the Industrial RRs and Mine RRs would have been more likely to destroy the frames in use than the railroads as they were pushing their locomotives harder than the railroads. I know Standard Steel Works Co #10 (Baldwin's Steel plant) at our museum has some heavy frame welds just behind the pilot beam (haven't checked under the cab), and she was a modern little 0-4-0T.

-----.

History of #10, she was built in 1934 and worked at SSW until 1949, where she went to Wickwire-Spencer in Palmer Mass. In the 1970 she helped to start the Valley RR in Essex (privately owned separate from VALE), in 1999 she was moved to Shelburne Falls Trolley Museum, and in Oct 2008 she came to the Ct Eastern RR Museum in Willimantic, Ct.

Rich C.


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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 13, 2018 5:23 pm 

Joined: Mon Aug 23, 2004 5:10 pm
Posts: 971
Here are a couple of photos of welded repairs to PRR M-1b No. 6755 at the Railroad Museum of Pennsylvania, taken this afternoon. One shows a massive weld to the frame just behind the cylinder block, while the other shows repair to the link block. Looks to me like the engine was side-swiped or hit something pretty hard. The cylinder half-saddle is a replacement as well.


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 Post subject: Re: PRR T1 Build Update
PostPosted: Tue Feb 13, 2018 6:15 pm 

Joined: Thu May 24, 2012 1:37 pm
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Mr. Laepple, is that a cast bed or just cast-steel frames? (They would weld about the same but be fabricated differently).

ISTR a couple of instances where cast beds were severely damaged, and I think this led to the engines involved being scrapped. I don't think the Hudson in the Gulf Curve accident at Little Falls had a full cast bed but was certainly not repairable; the situation could be that damage substantial enough to knock a bed sufficiently out of line would 'total' enough of the other structure and other components on the engine.

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