摘要 |
A threaded joint for pipes includes a pin member and a box member, the pin member having an external thread configured to correspond to an internal thread of the box member, a thread form of the internal and external threads having generally dovetail-shaped profile with stab flanks and load flanks and flat roots and crests, wherein the internal threads are increasing in width in one direction on the box and the external threads are increasing in width in the other direction on the pin, so the roots, crests, and flanks of the threads move together and form seals that resist the flow of fluids between the seals. The threaded joint further includes a fluoropolymer-based coating applied to specific regions of the internal and external threads and a resin coating disposed in regions of the internal and external threads that are devoid of the fluoropolymer-based coating, wherein the fluoropolymer-based coating and the resin coating are configured to form a layer of substantially uniform thickness on the overall surface of the internal and external threads. |