HEAT-INSULATED OIL WELL TUBING Russian patent published in 2004 - IPC

FIELD: oil and gas industry, extraction of oil and gas with utilization of pressure pumping of heat transfer agent into bed, heat insulation of pipe-lines employed in other branches of industry. SUBSTANCE: heat-insulated oil well tubing includes intercoupled bearing tubes and jackets placed concentrically. Temperature expansion compensator in the form of quarter-torus diaphragms fixed between jackets. Bearing tube is internal and internal bearing tubes are joined tube to tube. Internal bearing tube is made with upset end with female conical thread on one side and with male conical thread on the other side. Temperature expansion compensator in the form of quarter- torus diaphragm is put on internal bearing tube on side of male conical thread with concave part outwards and is butt joined to jacket with one end having larger diameter and is fillet joined to internal bearing tube with other end having smaller diameter. On side of upset end of internal bearing tube jacket is made fast to internal bearing tube by means of ring-diaphragm. EFFECT: increased operational reliability of heat-insulated oil well tubing. 1 dwg