Patent ID: 9611535
Date: 2017-04-04
CPC Classifications: B23D,B23F,B24B,C23C

Claim:
1. A method for forming a profile having at least three consecutive concave surfaces in an internal surface of a metal part: piercing the metal part to create the at least three consecutive concave surfaces comprising a first concave surface having a first radius of curvature, a second concave surface having a second radius of curvature and a third concave surface having a third radius of curvature, the second concave surface being between the first and third concave surfaces and the second radius of curvature being different from the first and third radii of curvature; carburizing the metal part; grinding the second concave surface of the internal surface; and linear broaching the first and third concave surfaces with an abrasive-covered broach.