Sintered Bushes are Self-Lubricating bearing
Posted on:1/2/2006
Written By: Manish Dadhania
Website: www.precisionsintered.com
| The properties of self-lubricating bearings are determined by the defined density of the bearing material. After forming, sintering and sizing, the bearings are vacuum impregnated with SAE 40 oil that provides lubricant which is metered from the bearing to the shaft during rotation. The resulting number of pores acts as a reservoir for the lubricant. |
PSP offers sintered bronze oil impregnated bearings, Plain, flanged bearings, thrust bearings. Our sintered bronze products conform to ASTM / MPIF/IS/DIN Standards recommended Materials, dimensions and tolerances. After forming, sintering and sizing, the bearings are vacuum impregnated with SAE 40 oil that provides lubricant which is metered from the bearing to the shaft during rotation. Standard sintered bronze bearings and wear plates will function satisfactorily in temperatures ranging from -60ºc to 200ºc. Consult us if your application is subject to higher temperatures or other specific operating conditions.
The properties of self-lubricating bearings are determined by the defined density of the bearing material. The resulting number of pores acts as a reservoir for the lubricant. Through linking of the pores, a canal system is produced which forms a lubricating film on the contact surface and helps to circulate the lubricant. In running condition, within a short time equilibrium is established in the circulation of the lubricant.
Powder metallurgy is the process where by metal parts in large quantities can be made by compressing and sintering various powdered metals such as brass, bronze, stainless steel, and iron. Self-lubricating sintered metal bearings are produced by powder metallurgical methods. Powder metals are fed into a die and axially compacted. The resulting "green parts" are sintered in a protective gas atmosphere at temperatures below the melting point. Through diffusion, a bonding results at the points of contact of the powder particles. This bonding defines the strength of components. Through subsequent calibration, the specified tolerances -- primarily in the bore -- are met without blocking up the pores. Vacuum impregnation with a suitable lubricant is the final stage of the process. To improve the feed in automatic bowl feed systems, there is normally an additional operation to produce a dry-to-the-touch bearing and supplementary heat treatments may be employed.
The physical properties of the final product are comparable to those of cast or wrought products of the same composition, if the parts are processed to provide high density. A lower density will result in lower physical properties.
1) Design
PSP designs all tooling required to produce a part to customer specifications.
2) Blending
Metal powders are first mixed with lubricants and/or other alloys to produce a homogeneous blend of ingredients. Often the blending is done by the metal powder producer.
3) Compaction
The powder is gravity-fed into the die and is usually compacted at room temperature. The most common compacting pressures are in the 30 - 50 tons per square inch range. PSP has automated pressing equipment ranging from 4 - 250 tons.
4) Sintering
During sintering the pressed parts move through a controlled-atmosphere furnace. The pressed powder particles fuse together, forming metallurgical bonds. PSP has high temperature sintering capabilities up to 3000 degrees F.
5) Secondary operations
PSP can provide the part with a variety of secondary operations including grinding, impregnating, drilling, tapping, repressing and reaming.