摘要 |
A threaded joint for an oil well pipe having a tapered thread having roughly the shape of a buttress thread, a pin (11) having a male thread and a box (21) having a female thread, a seal and a torque shoulder, characterized in that (i) the load flank angle ( alpha ) of the threads is -20 DEG or greater and less than 0 DEG , the stab flank angle ( theta ) is greater than 30 DEG and at most 60 DEG (ii) there is a positive amount of interference between the male threads and the female threads, and (iii) during and at the completion of make-up, the load flanks and the stab flanks are contacting each other, and there is a gap between the crests and the roots. <IMAGE> |