To provide a manufacturing method of a race for a thrust needle bearing which is excellent in processing performance, favorable in an yield of a material, and can be manufactured at low cost.
A manufacturing method of a race for a needle bearing comprises: a cutting process for cutting a wire rod or a round rod material of medium carbon steel to a prescribed length, and manufacturing a raw material; a forging process for forging the raw material and forming a flat-shaped first middle raw material; a grinding process for applying grinding processing to the surface of the first middle raw material and finishing it to a second middle raw material having a prescribed shape and surface roughness; a shearing process for press-processing the second middle raw material, thirling its center, and separating it to a ring-shaped third middle raw material and a thirled material 25; a burring process for erecting a flange at the internal peripheral edge side or the external peripheral edge side of the third middle raw material, and forming it to a fourth middle raw material having a prescribed shape; and a heat treatment process for applying hardening treatment such as carbonitriding, quenching and tempering to the fourth middle raw material, and finishing it as the race.
TAKEMURA HIROMICHI
JP2011174506A | 2011-09-08 | |||
JP2008082434A | 2008-04-10 | |||
JP2007170447A | 2007-07-05 | |||
JP2009250371A | 2009-10-29 | |||
JP2002180203A | 2002-06-26 |
Next Patent: HYDRAULIC CONTINUOUSLY VARIABLE TRANSMISSION