| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve constructing property in a threaded joint fitting a pin having external thread and a shoulder part on the outer face of a pipe into a box having internal thread and a shoulder part corresponding to the pin on the inner face of the pipe by forming the threaded parts into parallel thread arranged in a staircase-shape consisting of different pitch diameters. SOLUTION: This thread joint for a landslip suppressing pile is constituted of a pin 1 and a box 2, a shoulder part 3 is only provided on the extreme end of the box, and a threaded part is composed of parallel thread 4 of large diameter pitch and parallel thread of small diameter pitch arranged staircase- likely. By thread element formed into parallel thread in this way and progressing fastening which is a defect in the case of ordinary taper thread, a problem of rise of torque can be dissolved. Namely even when fastening is progressed, rise of grease pressure accompanying increase of thread interference allowance is not generated, and fastening can be stably completed in low torque by manual fastening. Further, the threaded part can be formed into multiple thread, hence the rotation quantity can be reduced even if it is parallel thread, and the number of rotation can be restrained.</p> |
