How are rod/main bearings made?

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The Iron Icon
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How are rod/main bearings made?

Post by The Iron Icon »

Ive seen and looked at how bearing were poured back in the old days for some pretty old stuff. But have yet to find much on how bearings are made today. Just something vie been interested in learning. any info out there?
V12MECH
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Re: How are rod/main bearings made?

Post by V12MECH »

Robots in China most likely, aside from that, if you have a project in mind currently or down the road, buy the rings and bearings now, the way things are going some of these items might be in short supply 6 months or a year from now, or much more expensive, I have been picking up .010, 020" rings , bearings , etc. for my stuff so down the road when I make a phone call I don't hear" nope, sorry " !
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Re: How are rod/main bearings made?

Post by hoodeng »

Most bearings are plated onto a steel backing using various compositions of metals for different attributes/benefits. Some race steel back bearings also utilize coatings on the running surfaces. They are still produced in the USA and Australia and a number of other kindred countries.

Old white metal bearings that were cast into housings and rods used a different process, the housings were heated and fluxed the bearing was then 'run' in a mould mounted around the housing. On the separation line there was also tin laminated shims on some bearings, as bearings got loose, evident by a rumble when running ,the shims could be peeled off till a required clearance was met. Run bearings in production could be turned to a final finish, they could also be scraped.

In my apprenticeship white metal bearings were still used on rolling stock, they were referred to as 'brasses' these had a basic thick cast layer of white metal deposited on the face of a brass mounting block, this was filed to shape with a dreadnought file, then scraped for fit, eight axles a day every day.
If you really plowed into them you could reduce the mountain of axles in the stockpile to a slightly smaller mountain, you could never win.
In service it was the oilers job to rake up the oil soaked cotton waste in the bottom of the bearing box to supply lube to the bearings when trains were examined before dispatch, if not performed the axle could suffer what was called a 'hot box' and melt the white metal away from the axle, they could also catch fire... Until Timken made demountable axle assys, that is why you see the three bolts on the ends of nearly all rolling stock.

Cheers.
BCjohnny
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Re: How are rod/main bearings made?

Post by BCjohnny »

'Tri - Metal' type bearings usually have the main 'bronze' (usually copper/lead) layer cast (or more recently sintered) onto the steel backing, and a 'flash' plating of a Babbit type material over the whole shell

The plating is sometimes omitted in certain HD applications as, being that it's also plated onto onto the steel backing as well, can become unstable under heavy load

Reticular Aluminium Tin bearings are made IIRC by a thermal laminating / sintering type process

In the UK Vandervell were a leading developer of the former, Glacier the latter ...... both now gone

Interestingly some production applications now use a heavier duty Tri-Metal in the rod, and Al/Sn in the more lightly loaded cap
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Re: How are rod/main bearings made?

Post by In-Tech »

King "allecular" and AL are broached to size within tenths.
Heat is energy, energy is horsepower...but you gotta control the heat.
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Dan Timberlake
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Re: How are rod/main bearings made?

Post by Dan Timberlake »

Hi BCJohnny,

"Interestingly some production applications now use a heavier duty Tri-Metal in the rod, and Al/Sn in the more lightly loaded cap"

very interesting indeed.

Are those trucks, gasoline, diesel ???
PackardV8
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Re: How are rod/main bearings made?

Post by PackardV8 »

Some of both. Also, this takes us back to the bearing tang thread. Many of these newer designs have no tangs.
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Re: How are rod/main bearings made?

Post by Truckedup »

The steel back insert bearing as we know it was developed by Allison Engineering around 1921. V type aircraft engines had bronze bearing shells with a very short life span as the engines got more powerful..It was tricky to get the bearing material bonded to the steel. Not even Rolls Royce could figure it out ...
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
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Re: How are rod/main bearings made?

Post by BCjohnny »

Dan Timberlake wrote: Mon Aug 08, 2022 12:30 pm Hi BCJohnny,

"Interestingly some production applications now use a heavier duty Tri-Metal in the rod, and Al/Sn in the more lightly loaded cap"

very interesting indeed.

Are those trucks, gasoline, diesel ???
Dan .......

I don't do much 'modern' stuff if I can help it, but the one I've come across is the Ford I4 'wet belt' 2.0 diesel made at Romeo ..... very common engine used in Transits etc ...... light truck but relatively 'stressed' tune

From the ones I've seen I'd be in no rush to buy one, I mostly grasp the decisions / economics but otherwise an engineering dichotomy IMHO

Cheers John
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