METHOD OF PROTECTION OF SLEEVE THREADED JOINT OF PIPES FROM CORROSION Russian patent published in 2000 - IPC

FIELD: construction engineering; erection of pipe lines; shipbuilding; oil and gas producing industry and other industries. SUBSTANCE: circular groove is made on inner surface of center portion of sleeve, depth of this groove exceeds depth of sleeve thread profile; then coat made from thermoplastic material is applied to circular groove at least to the level of minor diameter of thread of sleeve and thread is cut on thermoplastic coat of sleeve in the course of connection of pipes by means of sleeve. Additional grooves may be made on inner surface of sleeve which are symmetrical relative to center circular groove, after which thermoplastic coat is applied. EFFECT: enhanced reliability. 4 dwg