| 摘要 |
PROBLEM TO BE SOLVED: To provide a pipe joint excellent in seizure resistance for preventing a seizure at a screw engaging part when a screw joint of a oil well pipe is screwed in, and provide a manufacturing method of the pipe joint. SOLUTION: This pipe joint is a coupling type where a pin with a taper male screw part formed on an outer peripheral surface at a tip part of a pipe is screwed into a box with taper female screw part engaged with the taper male screw part on inner peripheral surfaces on both ends of a short pipe. One pitch of the male screw is smaller than one pitch of the female screw by 1 to 7 micron, and this makes the pipe joint excellent in seizure resistance. When the pipe joint is manufactured on a lathe, screw cutting is conducted such that the setting for the male screw is smaller than that of the female screw by 1 to 7 microns in manufacture of this pipe joint excellent in the seizure resistance.
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