PURPOSE: To make possible to perform a cutting operation with high efficiency by controlling a remaining thickness of a tube end within a given range with the aid of a measuring device and a calculator.
CONSTITUTION: The inner surface of a steel pipe 1 is worked with a cutter 6 and a remaining thickness is measured every revolution with a measuring device 13 of the remaining thickness consisted of a photodiode. A max. allowable value and a mim. allowable value of the remaining thickness and a standard rotation value at the time of operation end are set on a setting table 14 respectively. A signal based on a position of the rotation of the steel pipe detected by a rotary encoder 11 and a signal based upon a detection value with the device 13 are supplied to the calculator 15 respectively, whereby the max. and mim. values of the remaining thickness every rotation of the steel pipe is obtained and shown in 17. The working machine is controlled by the signal of a judging device of a completion of a chamfering.
OKAZAKI YOSHIHIRO
YOSHIDA TSUNEO
SAKURAI KATSUMI
TANABE HIDEYA
