Patent ID: 6062777
Filing Date: 2000-05-16
Classification: B23G,Y10T

Abstract:
A method for threading a cylindrical part on a rotary spindle threading machine having a die head with at least six circumferentially spaced blocks therein, a first set of three blocks equally spaced circumferentially and a second set of three blocks located intermediate the blocks in the first set, the blocks in said second set being equally spaced circumferentially from each other, said method comprising:providing a set of four thread chasers each having a unique profile on a cutting edge thereof for progressively forming threads on said cylindrical part,mounting three of the four thread chasers in the first set of blocks and the remaining chaser in one of the blocks of the second set,mounting turning tools in the remaining two blocks of the die head,advancing the turning tools to remove excess metal from the cylindrical part while the die head of the rotary spindle machine is rotated, andradially advancing said chasers to perform a thread cutting operation on the cylindrical part while the die head of the rotary spindle machine is rotated,whereby metal burrs on the first and last portion of threads cut on said part are significantly decreased by reducing the total tool cutting forces imposed on the part and said threading machine.