THREADED CONNECTION OF PIPES FOR OIL WELLS Russian patent published in 2021 - IPC F16L15/04 E21B17/42 

FIELD: oil and gas industry.

SUBSTANCE: according to the invention, there is provided a pipe thread joint for oil wells of integral type, comprising nipple 2 having an external thread section 4, which is an external conical thread, at one end of the steel pipe; and coupling 3 having internal thread section 5, which is internal conical thread connected to external thread section, at one end of steel pipe. Design, in which nipple and coupling are in metal contact with each other for sealing of fluid medium, is made in at least one section of seal on side of external peripheral surface of nipple from end side of pipe and sealing section on side of inner peripheral surface of coupling on end side of pipe. Minimum value L_min (mm) of length L of thread (mm) in rows of external taper thread and internal taper thread is defined by expression (1): L_min = ((t × (Dt)) / (α_t × D_t/√3)) × coefficient of strength, and length L of thread (mm) in rows of thread satisfy expression (2): L_min × 1.0 ≤ L ≤ L_min × 2.5.

EFFECT: threaded connection of pipes for oil wells, in which effective thread length is provided and processing time and installation time are reduced.

1 cl, 2 dwg, 1 tbl