To provide a manufacturing method and an end machining apparatus for a steel pipe for a line pipe, having very high dimensional accuracy while holding down the manufacturing cost to the utmost.
This end machining apparatus for a steel pipe for a line pipe is an apparatus for performing cutting for the inner surface simultaneously chamfering the inner and outer surfaces and end faces of the end of a fixed steel pipe after manufacturing a pipe. An inner surface chamfering tool 6, an outer surface chamfering tool 7, an end face chamfering tool 8 and an inner surface cutting tool 9 are disposed on the side of a face plate opposite to the end face of the steel pipe. In the chamfering process for the end part of the steel pipe after manufacturing the pipe, inner surface cutting is also performed simultaneously with the chamfering for the inner and outer surfaces and the end faces. Thus, all machining at the pipe end part is performed in one centering, so the pipe end shape with very high accuracy can be formed so as to manufacture the steel pipe for the line pipe with very high accuracy. Furthermore, since machining for the pipe end part is ended in one process, the work efficiency is improved, the construction cost in a spot can be remarkably reduced, and the manufacturing cost for the line pipe can be lowered.
Tetsuya Mizogami
Yoshinori Iwahara