Friction Bearings – How Old Is This Term?


Bob Chaparro
 

Friction Bearings – How Old Is This Term?

Way back on 6/6/16, Dave Evans defended Timken against the commonly publicized criticism that Timken invented the term “friction bearing” as a put-down against the makers of plain/solid wheel bearings.                                                                                                                                                                                

He stated, “Can we please stop claiming that the Timken Sales department "invented" the term friction bearing? In engineering, the term "friction bearing" predates the Timken company by something of the order of 100 years.”

He also stated, "… while that term may not have been widely used by many in the industry close to maintenance and operations, or accounting and sales forces that used the CBD, it was used by organizations such as the railroad division of the American Society of Mechanical Engineers (ASME) - who actually designed the equipment.”

Has anyone actually documented that the railroad division of the American Society of Mechanical Engineers used the term “friction bearing”, as asserted by Dave?

Thanks.

Bob Chaparro

Hemet, CA


D. Scott Chatfield
 

But were they using "friction bearing" to describe a type of journal bearing or were they using it correctly to describe one type of side plate bearing?

"Friction bearing" is an oxymoron since a bearing by definition is an anti-friction device.  

As has been pointed out to me in the past, plain journal bearings are a type of sleeve bearing, and the "solid" journal bearing is a variant developed later (1940s?), so not all plain bearings are solid bearings.  But before the development of the roller journal bearing there was really no reason to call journal bearings anything other than just journal bearings.  The use of the inaccurate and unnecessary term "friction bearing" had to start somewhere. 


Scott Chatfield


Daniel A. Mitchell
 

"before the development of the roller journal bearing” ...

This type bearing was known to the ROMANS and other early historical civilizations. Their versions were crude to be sure, but they well understood the principals involved. Wooden and stone, and later bronze, balls and rollers were used. Their early purpose was mostly to move or rotate heavy weights. If you want the roots of the terms used for bearings, you’ll need to go back a LONG ways.

It’s not the roller principal that’s important here, but the ability to make PRECISION components capable of running at higher speeds. This developed sometime in the mid-1800s, and was well accomplished by WWI. It was the ability to make precision anti-friction bearings at low cost in large quantities that revolutionized the industry.

Dan Mitchell
==========



On Jul 4, 2021, at 11:30 PM, D. Scott
 <blindog@...> wrote:

But were they using "friction bearing" to describe a type of journal bearing or were they using it correctly to describe one type of side plate bearing?

"Friction bearing" is an oxymoron since a bearing by definition is an anti-friction device.  

As has been pointed out to me in the past, plain journal bearings are a type of sleeve bearing, and the "solid" journal bearing is a variant developed later (1940s?), so not all plain bearings are solid bearings.  But before the development of the roller journal bearing there was really no reason to call journal bearings anything other than just journal bearings.  The use of the inaccurate and unnecessary term "friction bearing" had to start somewhere. 


Scott Chatfield


Tim O'Connor
 


I disagree. By "definition" a bearing is something that bears a weight, if words mean anything.

I have heard railroaders use the 'friction bearing' term. Terminology in the Cyclopedias is technical
and is intended for use by mech engineers machinists draftsman and skilled maintenance and construction
workers so no doubt others made up their own terms that varied by place and time.


On 7/4/2021 11:30 PM, D. Scott Chatfield wrote

But were they using "friction bearing" to describe a type of journal bearing or were they using it correctly to describe one type of side plate bearing?

"Friction bearing" is an oxymoron since a bearing by definition is an anti-friction device.  

As has been pointed out to me in the past, plain journal bearings are a type of sleeve bearing, and the "solid" journal bearing is a variant developed later (1940s?), so not all plain bearings are solid bearings.  But before the development of the roller journal bearing there was really no reason to call journal bearings anything other than just journal bearings.  The use of the inaccurate and unnecessary term "friction bearing" had to start somewhere. 


Scott Chatfield


--
Tim O'Connor
Sterling, Massachusetts


devansprr
 

ugh...

It's back.

The term bearing in the broad sense means a method to support the relative motion of one surface against another - a bearing surface, usually under some manner of "load" that need to be transferred from one surface to the other..

The vast majority of bearings are designed to reduce friction, but they are not "anti-friction". Outside of roller bearings, pretty much ALL bearings have some amount of friction.

In the case of railroad journal bearings of the original types (you can do patent searches back to the early 1800's on railroad bearings as friction bearings, to include a number of British patents), when first starting the train, the axles and bearings are truly in direct contact and suffering from significant sliding friction between the axle and the bearing.

Within a few axle revolutions, with enough oil and some manner of helping spread the oil, if the speed was high enough (I suspect at least one and maybe two mph), an oil film between the two surfaces would be established that turned the bearing into a hydrodynamic bearing, where there was no longer direct contact between the axle and bearing. But with one side of that oil film "stuck" to the axle, and the other side of that oil film "stuck" to the bearing, there is significant shear within that fluid, and shear in fluid is itself, by nearly every properly trained mechanical engineer I have ever known, referred to as "friction", which is why the oil in your car engine, which also has hydrodynamic bearings on the crank shaft, also gets hot (from the friction!) (And that same shear friction is why pressure drops along a pipe moving fluids - that is also friction.)

Which is why it was so hard to start a train with "friction bearings" and why engineers, especially steam locomotive engineers, would "take slack" so that only a few cars at a time were starting, otherwise the direct contact friction in the cars that have not yet established the hydrodynamic oil film was so high it would stall the locomotive, or exert so much drawbar pull to cause the drivers to slip.

A roller bearing can properly be called an "Anti-friction" bearing because there is NO sliding between the contact surfaces inside the roller bearing that transmit the load (weight of the car) from the truck sideframe to the axle - the contact is just like the wheel rolling on the rail.

Bottom line, there is significant friction occurring in the original railroad journal bearings, and almost no "friction" in today's modern roller bearings (there is some friction in the bearing cages, but that friction is not related to transmitting the weight of the car to the axle.)

What I really don't understand is where does this seemingly "hate" for Timken come from? Roller bearings, especially Timken's tapered roller bearings, where a vast improvement in safety and economy of freight rail. The fact that Timken stuck with it for nearly 50 years before wide spread adoption is amazing to me. The real tragedy is the refusal of railroad line engineers to adopt the technology. That refusal to accept change is not unique - having studied "disruptive" technologies one finds this to be quite common across many industries - a current example being SpaceX's Falcon 9 taking over the commercial satellite launch market from aerospace companies that refused to modernize their rockets (effectively derivatives of late 1950 ICBM's.)

The 1929 report of a test train of 100 roller bearing equipped hoppers on the PRR helps illustrate the inability of the PRR's engineering staff to understand how roller bearings work. There is a copy of the draft report in the PA state Archives that I hope to copy and analyze some day but a quick review of it about 5 years ago highlighted the almost irrational resistance to the roller bearing concept by a number of PRR engineers (that draft has a LOT of pencil'd markups.)

If there is ANY criticism due, it is of the RR's line engineers (not the locomotive engineers), refusal to change to a safer and more efficient technology (although there were economic dis-incentives to adopt roller bearings in freight service.)

Dave Evans


Jeff Ford
 

One of the greatest dis-incentives I've heard of was the various railroads' reluctance to spend the premium to equip interchange equipment with roller bearings.  The thought there being that the investment would disappear into interchange service and ultimately benefit "the competition."

It is bewildering that PRR or any of the other coal-hauling roads didn't see the benefit in equipping their captive fleets.  Makes you wonder what train lengths a C&O H-8 or PRR J-1 could start had the cars been equipped with roller bearings. 

$0.02,
-Jeff Ford
Sanger, Texas


Dave Nelson
 

For the STMFC list it probably goes back to when the list was hosted on a university server and a schism developed between those who argued on behalf of physical and jargon accuracy vs. I can do whatever I damn well please on my model railroad.   IIRC the people who were interested in the facts departed to start this list on a different server and a different admin.  This list on groups.io is the third incarnation of that break.  In all cases the Admin was and is Mike Brock with help from Jeff Aley.

Please correct me if this account misses anything important.

 

Dave Nelson

 

From: main@RealSTMFC.groups.io [mailto:main@RealSTMFC.groups.io] On Behalf Of devansprr
Sent: Monday, July 05, 2021 8:55 AM
To: main@RealSTMFC.groups.io
Subject: Re: [RealSTMFC] Friction Bearings – How Old Is This Term?


What I really don't understand is where does this seemingly "hate" for Timken come from?

Dave Evans


devansprr
 

Jeff,

Actually the C&O was an early adopter for their hoppers since many were effectively in captive service. And the benefit of roller bearings when starting a coal train was significant (as the PRR tests demonstrated, especially in cold weather.)

The C&O soon discovered that their hump yards were too steep for the roller bearing equipped hoppers - they rolled much more freely and ended up descending too fast. IIRC, in the early days of RB deployments those cars had special markings.

UP was also an early adopter for their stock car fleet - the higher speeds the roller bearings supported could, on some solid trains of stock cars, reduce schedule run time enough to eliminate a watering stop.

And you are quite correct - the prevailing view into the 1950's was that the much more expensive roller bearings would not have any "pay back" if the cars ranged widely in interchange service - especially for the smaller roads.

In addition, there were competing roller bearings that were not tapered roller bearings, and they were not as free rolling, nor as reliable, as the Timken tapered roller bearings. Eventually Timken licensed their patents to the other vendors so they could also make tapered roller bearings. I do not know if that helped reduce resistance to tapered roller bearings being adopted industry wide.

Dave Evans


steve_wintner
 

I can only speculate about their mindset, but speaking as an engineer who has faced the hydrostatic vs. rolling element bearing issue in his own career in aerospace and turbomachinery, I suspect there was substantial concern about the durability and tolerance to poor maintenance. Hydrostatic bearings are very tolerant to abuse - including the direct injection of metal chips into inappropriate place, like, say, the bearing journals (ask me how I know) - whereas rolling elements are relatively fragile. The prevailing attitude amongst engineers I have worked with reflects that. "If it ain't broke, don't fix it." 

Time has shown that rolling elements can be successful, I don't doubt that. But hesitancy to adopt a new, more expensive device of what seemed at the time questionable durability doesn't surprise me in the least.

As for terms, at least in my experience, I and my colleagues rarely manage to stick to standard terms across one firm, let alone an industry. Gas turbine vanes are commonly called nozzles, blades are sometimes called buckets, outer air seals are called liners, inner air seals are called diaphragms, and on and on - I imagine the railroad industry was similar (in our case, it has historical roots, mostly). Attempting to follow industry standard terminology is fine, but I imagine terms like journal, journal bearing, plain bearing, hydrostatic bearing, etc. all were found in official documents & usage.

Steve


devansprr
 

Dave,

You raise a good point, and perhaps I need to be less serious about this - modelers are entitled to use whatever term they like. The engineer in me wants to be accurate, perhaps too accurate, but then the rolling characteristics of roller bearing versus "plain journal" bearings was quite different, and that has operational implications for those trying to accurately model STMFC operations.

I used to be impressed with the idea of a steam locomotive on a model railroad crawling away with a freight in tow at 1 smph. Big flywheels, great decoder, etc. But I would now challenge anyone to show me a movie of a steam locomotive sustaining a 1 mph speed for any significant distance when starting a train. Even though slack action was frowned upon, when starting a freight train with plain journal bearings, the engineer really had to take slack, reverse, and then quickly get the locomotive up to at least 2 to 3 mph until all of the slack was gone and the entire train was moving. They would have to increase the steam flow to accomplish that as the train started, but you didn't want to be any faster than 3 mph until the caboose was moving. Then and only then would the train accelerate.

Personally I think that would be a neat thing to model but YMMV....

With all roller bearings in the consists today, the need "take-slack" and then to "walk-out" the slack disappeared, so I suspect that part of the art of being a steam locomotive engineer has been lost.

As for layout owner terminology, to each his own I guess, but then I know very few PRR modelers who call their cabins "cabooses" ;-)

Dave Evans


np328
 

I cannot help but wonder...
     We here have the wonderful ability to use hindsight. I recall a professor in college stating that it takes 30 years for things to settle and calm down before we can come to a consensus on historical events. Since this STMFC timeline stops effectively at 1960, well, we are there with some time to spare. 

However first, a set of guideposts need to be put in place.
       And those guideposts are as I have stated to my historical society from time to time: Never forget - that a railroad is first and foremost a business established and indeed, required by law to (1) make a profit and (2) protect at all times, the shareholders financial interests.      

So with that in mind, and about the adoption of roller bearings. How soon would a payoff be seen?  
         I am not arguing that an eventual payoff would not be there. What I am hoping to establish is - the reports of roller bearing relief, I'll call it. Are there many other than the PRR report in historical engineering files of the railroads. I will admit I have never looked specifically. I know the NP was pleased with the Timken locomotive and that it did influence locomotive designing. (And yes, I know why the NP bought it.) 

         I had the fortune to research at times over the years with a civil engineer (Jerry) formerly employed by the NP, GN, and BN, and while researching posed him questions like this one. Track realignment projects, grade reduction projects, tunneling projects, and other matters. 

(Typical 1980-2010 research conversation and I have uncovered some file tangential to the days research. ) 
Me: Hey Jerry, this looks like a great idea! Why was it never done? 
Jerry: Oh that project. Yeah it was a OK idea.  Why wasn't it done? Because it would not have given a return on the monies spent within four years. 
Me: It would have paid dividends back for the last fifty years now and forever after.      So four years ROI, that's what a project needs to be OK'd? 
Jerry: Well, that was back then in the 50s and 60s. It's tighter now. 

    And so,  would you like to be the person that submits an AFE that states:

      This will cost a good sum of money, of which much of it may need to be borrowed, and we will need to cover the interest on that. It will require that much of the current stock in our storehouses be rendered obsolete before its time and so we will lose that benefit. Besides that, not all sideframe or truck castings on the currently running freight cars are adoptable so we will need to handle that additional aspect with our shop forces. Payback or ROI of this project to be realized will take some time to be before it starts to accrue.  And as we expand this program, the return on investment will start to diminish well before the program is complete.
     Meanwhile we need to keep in place some of the prior mentioned items such as brasses, cotton waste, and other misc. parts so that we can readily repair other railroads equipment when it breaks down while it is on our property. (So if it is used on captive equipment, the train must be pure, with home road equipment only in those trains, to answer to Jeff. Or else benefits diminish accordingly.)  

     Yes, I know that monies for locomotives, other projects were borrowed however these are normally accompanied by reports of motive power or rolling stock needs written prior to the purchases. Some of those studies done by your railroad and mine covered years of compilation. After which more time where officers debated the merits.  

I do not think that anyone was consciously trying to gum up the works. I believe that it is just that - a quick quantifiable payback was hard to be found.   
     And as is stated elsewhere: If your paycheck depends on you ignoring the facts, many can find a way. And the bigger the prestige and money, the farther one will reach for reasons to ignore the truth. 
     With aspects of "siloing" which have always been in business, another departments costs is not a concern as long as it does not come out of your budget. Train delays due to hotboxes were someone else's concern, not your departments budget. And fuel usage of the C&O H-8 or PRR J-1, not out of your budget. And so on.  

       To circle back, we open files to study the freight cars, and other stock, that are by now commonly one hundred years old and wonder - why?
And have the benefit of hindsight they never enjoyed.  

                                                                                                                                                                                                                      James Dick - Roseville, MN