Railway Preservation News
http://rypn.org/forums/

Uh Oh, Journal Bearing Terms
http://rypn.org/forums/viewtopic.php?f=1&t=46831
Page 1 of 2

Author:  jayrod [ Tue Aug 16, 2022 3:35 pm ]
Post subject:  Uh Oh, Journal Bearing Terms

An interesting find while cataloging drawings:

Ya know how there always seems to be feathers ruffled when someone refers to plain brass (another misnomer) bearings on axle journals as friction bearings or journals?

And that it always gets attributed to a Timken marketing ploy?

Well.... I just cataloged PRR drawing number D-88792 dated 6-11-29 for Class 3F-T2 trucks titled "TENDERS & FREIGHT CARS TRUCK EQUALIZER WITH FRICTION JOURNAL BOX".

Sorry. Couldn't resist.

[OP pulls chair back, crawls under desk and pulls chair back up]

Author:  mldeets [ Tue Aug 16, 2022 4:45 pm ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

What? You're not even going to make popcorn?........mld

Author:  jayrod [ Tue Aug 16, 2022 5:09 pm ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

I should have made the popcorn before posting. Too late now.

Author:  Rick Rowlands [ Tue Aug 16, 2022 7:55 pm ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

Well if the STANDARD RAILROAD says that is what it is, then that must be it! Who could possibly dispute the STANDARD RAILROAD?

Author:  EDM [ Wed Aug 17, 2022 8:18 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

A good friend once said that if the PRR was the 'Standard Railroad of the World', there were other railroads that were the 'Superior Railroads...' Just saying...

Author:  Overmod [ Wed Aug 17, 2022 10:09 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

I suggest we get someone like Nick Fry or Chris Baer to review some of the relevant PRR documents to see how widespread this naming convention might have been.

If I remember correctly, NYC has at least one official document mentioning 'friction' bearings on locomotives -- it is in vol.2 of Tom's NYCSHS book on Mohawks.

The Timken 'connection' is actively spreading the term for a plain bearing, usually in a disparaging context. Note that the 'antifriction' argument for Roller Freight fell relatively flat -- it was the long-term naintenance and freedom from defects that carried the day for grease-lubricated M-931 or whatever the standard is AP bearings.

There are people who continue to call simple articulateds "Mallets" -- even thous this has Anatole spinning in his grave. In fact many railroaders referred to a hinged engine as a "Malley" -- at least they bothered to respect the pronunciation. One of the smartest steam enthusiasts I know, with an engineering degree from a reputable university, maintains that we should go by the chassis arrangement rather than the compounding system and call any engine so hinged a "Mallet" -- perhaps volume II of Wiener's 'Articulated Locomotives' (covering everything since 1930, which is every true high-speed simple articulated ever built) will have a different distinction: in the original (or the Kalmbach 1970 reprint) he sometimes uses "Mallet" or other terms in quotes when referring to a simple-expansion locomotive.

Out of respect for M. Mallet's explicit request, I don't call a simple-expansion hinged engine a Mallet. I don't call a plain bearing a 'friction' bearing, whether or not it's formally hydrodynamic. In either case, I have resolved not to be the equivalent of a grammar Nazi and presume to 'correct' anyone who uses such terms wrong...

Author:  NYCRRson [ Wed Aug 17, 2022 12:51 pm ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

To quote Harold Crouch (Long time NYCRR Mechanical Engineer that worked up into PC and maybe Conrail);

"Those Pennsy Guys Knew Everything, But Nobody Copied Them......"

Harold was one of the crew members that rode out on the smokebox of the NYCRR Niagara class steam locos while they did full speed testing with a dynamometer car and 20/30 coaches along as a load.

Later in life Harold was a bit hard of hearing, wonder why.

Author:  Dick_Morris [ Wed Aug 17, 2022 9:05 pm ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

Quote:
There are people who continue to call simple articulateds "Mallets" -- even though this has Anatole spinning in his grave. In fact many railroaders referred to a hinged engine as a "Malley" -- at least they bothered to respect the pronunciation.


My mom always called the SP cab forwards "Malleys." For several years in the mid to late 1940s she operated a Teletype, keying in manifests and hand delivering the hard copies in Kalmath Falls, Roseville, and Sacramento. That indicates to me that this was the name in common use by the railroaders she worked with.

Author:  Overmod [ Thu Aug 18, 2022 8:48 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

I came to the 'compound realization' very, very late. When I was a kid, my introduction to simple articulateds came, as with so much else, via Trains Magazine in the DPM years; I thought that all these hinged engines were called 'Mallets' and in fact...

...an early bicycle came with a headlight, made in England, that featured a center-mounted visored reflector, with a horizontal cylindrical battery holder on either side. This looked just like a picture of a Rio Grande 'Mallet' in early-'60s Trains, and that's what I thought of every time I looked at it. (Someone should find and duplicate the design, and market it to bicycling railfans!)

Author:  Stationary Engineer [ Fri Aug 19, 2022 12:35 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

Mallet's patent specifically called for compounding. His reasoning was that when his articulated engine slipped, the change in the receiver pressure would stop the slipping. So the Mallet locomotive incorporates his articulation design "and" compound operation. To me, the term compound Mallet is redundant. But the terms, compound Mallet Articulated locomotive or single expansion Mallet Articulated locomotive would be correct. The term Mallet Articulated could apply to both types. The shorten term simple Mallet, would be ok, I guess. Railway Age and Railway Mechanical Engineer used the term single expansion articulated. But that ignores not only the other forms of single expansion articulation, but also the more numerous (then American built Mallet engines) geared engines that were built in America and were in common use at the time. But generally not on class ones. I guess context matters.

Author:  Frisco1522 [ Fri Aug 19, 2022 8:56 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

And I always referred to them as solid bearings.
Considering that there should be no metal to metal contact, rather running on a film of oil or grease, friction bearings would melt.

Author:  John T [ Fri Aug 19, 2022 9:00 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

From 1919 https://www.google.com/books/edition/Ca ... frontcover

Author:  Overmod [ Fri Aug 19, 2022 9:25 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

The term 'journal bearing' is interesting, because it refers to the rotating bearing surface on the axle, rather than the thing in the truck frame that provides the tribology. So any form of bearing where the bare face of the axle rides against something, whether it be white metal, 'brass', an Isothermos type with nominal coolant channels, etc. -- is a journal bearing.

Technically a needle bearing might be thought of as a 'journal bearing' (as the needles provide a self-restoring hard surface on the 'journal' of the pin, for reducing wear and the development of lost motion, and aren't intended to rotate in a cage for 'friction reduction' as in full rolling-element bearings). Semantically a rolling-element bearing whose 'inner race' was machined into the axle rather than pressed on might be considered a 'journal' bearing, but I wouldn't.

The point about nomenclature might be more open except that Mallet himself appears to have argued, vociferously at times, that unless the arrangement explicitly featured compounding it was not a "Mallet" as he had intended and his patent protection indicated. I accepted the term 'Mallet' for any articulated locomotive with Bissel-hinged forward engine all the way up until I was in my '40s... then learned about the controversy, and precisely why we should respect the inventor's memory and respect his distinction. That in no way means that people are "wrong" if they want to refer to these hinged engines by the chassis inventor's name.

Author:  jayrod [ Fri Aug 19, 2022 9:32 am ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

Frisco1522 wrote:
And I always referred to them as solid bearings.
Considering that there should be no metal to metal contact, rather running on a film of oil or grease, friction bearings would melt.

I find it most effective, especially for the not as mechanically inclined, to differentiate by referring to them as “plain brass” and “roller” bearings. Simple and descriptive. Friction may be mentioned only as something to avoid by the use of either type of bearing.

Author:  Dick_Morris [ Fri Aug 19, 2022 10:10 pm ]
Post subject:  Re: Uh Oh, Journal Bearing Terms

Even "brass" may be a bit of a misnomer. From my reading, brass is generally a poor choice for bearings. The specs I've seen call for bronze or a shell lined with Babbitt or similar.

Page 1 of 2 All times are UTC - 5 hours [ DST ]
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/