SEALED THREADED JOINT FOR TUBING PIPES

摘要

 Sealed threaded joint for tubing pipes The invention belongs to the oil and gas-extraction industry. The joint contains male (1) and female (2) elements with trapezoidal threads (3) with 1:16 taper and contacting each other taper sealing (5) and bearing (6) end surfaces. The slope angle between the thread profile lead-in flank (7) and the thread axis normal line amounts to 10-24°, the slope angle between the load flank (8) and the thread axis normal line amounts to -4 to +5°. The thread profile crests (9) and lead-in flanks make gaps (10, 11) in between, 0,05-0,15 mm wide, during joint make-up process. The thread profile on the area of mating of the load flank and the crest and on the area of mating of lead-in flank and the crest is produced rounded, with the different rounding radii for the male and female elements. The bearing end surfaces have a 10-20° slope angle with the thread axis normal line. A slope angle between the sealing surface of the male element and the thread axis normal line amounts to 13-18°, a slope angle between the sealing surface of the female element and the thread axis normal line amounts to 8-12°. On the female element on the thread run-out area and on the area of mating of the sealing and the bearing end surfaces are produced circumferential grooves (12) and (14). The female element area of mating of the sealing surface and the circumferential groove (14) surface and the male element area of mating of the sealing surface and the thread run-out surface are produced rounded. High tightness of the joint under sufficient mechanical loads, its wear resistance during multiple makes and breaks and its operation are achieved.