SAE 660 Oil Impreg. Bushing Matl Equivalent?

[farmer2]

Does anyone know the Powder Metal equivalent spec for this?

SAE 660 is used on an old bushing dwg that uses bar or tubing to machine the bushing. Am looking to tool the bushing to make from oil impreg. powder metal and hopefully save money. Cost of machined bushing has increased 76% this year due to copper price increase.

Would SAE 841 Oil-Filled powder metal bronze be equivalent? I noticed that we use this callout on a different bushing?

If you have material properties or can point me to them, would appreciate it.

Thanks,

 

[unclesyd]

Checkout this site for information on oil impregnated bearings. They have a nice bearing calculator for Oilite Bearings.

http://www.beemerprecision.com/

 

[btrueblood]

Also see MPIF Standard 35, "Materials Standards for P/M Self-Lubricating Bearings",

http://www.mpif.org

For data on copper alloys, see

http://www.copper.org,

or more specifically:

http://www.copper.org/resources/properties/db/CDAPropertiesSelectionServlet.jsp?mode=basic

 

[farmer2]

Unclesyd,
Looks like the beemer bearing calculator will not give me the results I am looking for.

I have a bushing with a bore of 2.50, od of 3.00 and length of 3.5 inches. Shaft load on ID is 25,000 lb, speed is 11 RPM. Need to know if this is made from SAE 841 Oilube (P/M) with a yield strength of 11,000 psi and yield of 14,000 psi if it will be ok. . The press fit of the bushing at the od is very small and should be able to ignore the effect.

 

[unclesyd]

Your bearing application falls out on the P of the PV calculation. It is over but not by much so it would behove you to give one of the bearing supplies a call with your information as the overall PV isn't that bad.

Here is another supplier that carries both the SAE 660 and the SAE 841.

http://www.anchorbronze.com/932stocklist.htm

What is happening to the 660?

 

[farmer2]

Unclesyd,
Thanks for your replies.

The load on the shaft is actually higher - 30,000 lbs, instead of 25,000 lbs. In fact, the proof test load is 60,000 lbs for two shaft revolutions. The 660 has worked fine. We have been using a machined 660 bushing and the cost has increased 76% since the first of the year. I thought if the bushing was tooled and made from powder metal, it might reduce the cost even when tooling cost is considered.

It now appears that we need the 660 properties and that the 841 Oilite does not have the strength. I was looking for a P/M material equiv to the 660. Could the bushing be cast using 660? There is an O-ring groove on the ID which would require secondary machining. It is a flanged bushing.

 

[unclesyd]

I would check with Beemer or Anchor Bronze as they have continious cast bar/tube SAE 660 bearing material and might have what you need.

Even though I've used static cast bronze bearings I've found the continious cast material to be a far superior bearing.

 

[tripleZ]

Farmer,

Judging from the sizes you've listed, even with a material switch conventional P/M may not be the most cost effective way to go. Length might be an issue with this part. A 3.5" long part using a conventional 2.1:1 fill ratio means you've got a die with probably a minimum of 8" of useable length, all the while trying to eject a part with a 1/4" wall. The shape is simple, but getting the part out of the die and to print with sintering alone is going to be a whole other issue. I'm not saying it can't be done, but your selection of vendors might be limited.

 

[farmer2]

Unclesyd,

Sent a bushing dwg to Beemer and had a quote within 3 hrs.

Great service!

Thanks,

 

[unclesyd]

Thanks for the feedback.

Both companies have helped me cover you know what several times.