SEALING FITTINGS (VERSIONS) Russian patent published in 1999 - IPC

FIELD: oil field equipment; applicable, both, in capacity of wellhead equipment of oil wells and wellhead sealing equipment of these wells in emergency situations on wells, or during prolonged underground repair operations. SUBSTANCE: sealing fittings have body with channels accommodating shutoff devices for communication with pipe and annular spaces. Central opening is made in fittings body to pass process equipment. Faceplate is rigidly connected with coupling for suspension of tubing string being in sealed contact with body sealing surface. Faceplate has central opening with shaped recesses and sealing insert made in form of coupling tightly installed in body sealing surface. Coupling is connected from below with tubing, and from atop, with shutoff member for closing the tubing hollow. Coupling has turning bushing whose side projections are located in companion shaped recess of body central opening. Turning bushing has spring-loaded retainers which in fixed position are also located in companion shaped recess of body central opening. Side projections of turning bushing are located inside annular recess of body and in force contact due to pressure on well side. EFFECT: provision of sealing the wellhead without use of special sealing devices. 3 cl, 8 dwg