DEVICE FOR HERMETIC SEALING OF INNER SPACE IN STRING OF PUMP-COMPRESSOR PIPES AT LIFTING IT FROM WELL UNDER PRESSURE Russian patent published in 1999 - IPC

FIELD: oil and gas production industry. SUBSTANCE: this can be used for pipes of various diameters. Additional body of device allows for its transportation through pipes of large diameter. Shear pins are intended for fastening of additional body with main body during transportation of device through pipes of large diameter and permit main body to get free from additional body at transition into string of pipes of smaller diameter. Additional body is provided with members for sealing it relative to string of pump-compressor pipes of large diameter, and also with centering members. Actuator of main body fixing members is made in the form of spring-biased tie-rod with stop. Mounted on actuator is pusher of fixing members. Also provided is control mechanism which comprises shackle with hole pivotally installed on tie-rod. Fixed in hole are two cotters. Main body fixing members come into operation when device reaches open end of pipe string. Rod of actuator of main body additional fixing members is hollow and provided with piston. Piston has isolating diaphragm. Hollow is made in connecting sleeve of main body. Hollow in rod contains liquid phase of gas-generating mixture, and hollow in sleeve contains solid component of gas-generating mixture. Additional member for sealing space inside pipes ensures reliable sealing. Protective housing prevents wear of pipe space additional sealing member when transporting device through pipes of smaller diameter. EFFECT: higher efficiency. 5 dwg