| 摘要 |
PROBLEM TO BE SOLVED: To provide a thread joint for an oil well pipe that has a sufficient resistance to tensile force and compressive force, is easily manufacturable to a machining tolerance, excels in sealing performance, and is appreciably reliable. SOLUTION: The smaller clearance L (mm) of a clearance L1 (mm) between a thread top face 1a of a taper external thread 1 and a thread bottom face 2b of a taper internal thread 2 and a clearance L2 (mm) between a thread bottom face 1c of the taper external thread 1 and a thread top face 2c of the taper internal thread 2, a loaded face angleα( deg.), an inserted face angelβ( deg.), and an axial clearance 5 (mm) generable in a thread width direction or the difference between the thread width of the taper external thread 1 and the root width of the taper internal thread 2 engaged with each other, have the following relationship:δ<=L.(tanα+tanβ). If some degree of interference is required in the threaded portions, an initially set degree of thread interference H is provided by: H>2L. |
