Bearing heat treatment

Home/Uncategorized/Bearing heat treatment

Bearing heat treatment

Bearing heat treatment

(1) to expand the scope of GCR15 steel, general NSK 71938CDB angular contact ball bearings GCR15 steel M quenching ring effective wall thickness of 12MM below, but the BL quenching due to salt cooling ability, if the use of mixing, string moving, Water and other measures, ring effective wall thickness can be expanded to about 28MM.

(2) hardness and stability, good uniformity

As the BL transformation is a slow process, generally GCR15 steel 4H, GCR18MO steel 5H, ferrules in isothermal salt nitrate for a long time, the surface of the heart tissue transformation almost simultaneously, so the hardness is stable, all KOYO 52132RS angular contact ball bearings uniform Good, general GCR15 steel BL hardness after quenching 59 ~ 61HRC, uniformity ≤ 1HRC, unlike the ring when the ring is slightly larger than the quenching hardness, soft point, poor uniformity and other issues.

(3) reduce quenching, grinding cracks

In the railway, rolling mill bearing production, due to large ferrule size, heavy weight, M tissue brittle oil quenching, in order to obtain high hardness after quenching often take strong cooling measures, resulting in quenching micro-cracks; and BL quenching, due to The toughness of BL tissue is much better than that of M, and compressive stress up to -400 ~ -500MPA is formed on the surface, which greatly reduces the tendency of quenching KOYO crack. The surface compressive stress cancels the grinding stress and makes the overall stress Horizontal decline, greatly reducing the grinding cracks.

(4) bearing life increase

For large load to withstand the railway, rolling mill bearings, quenched by M after the main failure mode is used: When the inner sheath cracking, the outer wall of the outer wall of the block during use, the inner ring fragmentation, and austempered bearings SKF bearings in the impact toughness, the surface compressive stress, regardless of the assembly when the inner sleeve cracking, or the use of the outer wall of the block block block, greatly reduce the fragmentation of the sleeve, and can reduce the edge of the roller stress concentration. Therefore, after quenching after quenching than M, the average life expectancy and reliability increase

By | 2019-09-10T07:21:34+00:00 29 12 月, 2017|Uncategorized|Bearing heat treatment已关闭评论

About the Author: