Application-trunion of very large track back hoe. I.D. bearing 5"-
O.D. approx. 5.5" bearing approx, 7" long 2 per on steel shaft
(rockwell 42) 34.5" long. Back hoe subject to extreme shock loads and
hostile enviornment(talc mine). Bearing is lubricated with grease but
no seals. Will cut grease grooves. Must line bore trunion and make
oversize bushings. Discuss options phosphor, manganese, silicon,
alumna bronze, C93200. Pros and cons for each and any other options.
Thanks Robert Williams 3rrotec. P.S. Would like to know good reference
book to buy.

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Request for Question Clarification by krobert-ga on 25 Feb 2003 20:57 PST

3rrotec-ga,

Good to see you on Google Answers again! Do you have (or does anyone
else involved have) any concerns with constant wear due to the talc?

The following book is an excellent reference source on the topic of
lubrication and tribology:

ASM Handbook Volume 18: Friction, Lubrication, and Wear Technology
http://www.asminternational.org/Template.cfm?Section=Search&template=Ecommerce/ProductDisplay.cfm&ProductID=10493

What kind of detail were you looking for regarding the different
bronze alloy variations? What major concerns do you have with regard
to your application?

Best to you... lefty,

krobert-ga

Though I would like to, I don't have the background necessary to
research your question and I don't know if another researcher will or
not. However, finding an applicable referemce work sounds like a good
idea. I went to Amazon.com, entered "industrial lubrication" and got
76 "hits". You might take a look at some of those books to see if they
meet your needs.

Best of luck,

ericynot-ga

Glad you responded. Us "lefty's" have to stick together! I'm more
interested in the composition of the bronze than the lubrication. The
hostile enviornment is due mainly from grit generated in a mine (open
pit). Similar to any earth moving equipment. The backhoe has a jack
hammer, drill attachment. First they  jack hammer holes in the mine
bottom and walls. Then they blast the talc ore. The jack hammer
attachment is then removed and the bucket is put back on the back hoe.
The talc is then loaded on a conveyor and is "conveyed" onto big
Eucled trucks. The trunion I'm repairing is the first one under the
cab. It carries the whole load of the arms, jack hammer or bucket, and
the load. It is subject to tremendous pounding when they jack hammer
the holes. Over time the bushings tend to stretch and get loose in the
trunions. They begin to wear out and "egg" the trunion. I don't know
what alloy bronze Caterpillar uses, but it is too soft for this
application. We must be careful though! I've tried to replace some
bushings before with alumna bronze. They tend to crack or gall on the
shaft (higher rpm's). I will replace these with 550 bronze, but
looking for better material in the future. I'll do 6 to 8 of these a
year. Thanks Robert P.S. You would enjoy seeing the redneck
contraption I've come up with to line bore these jobs. Works good. I
always seem to end up with these "It can't be done" jobs. I guess I
enjoy stuff like this. Pays good too!