Direct connection type special-thread thermal-insulating oil pipe

Abstract

The invention discloses a direct connection type special-thread thermal-insulating oil pipe. The direct connection type special-thread thermal-insulating oil pipe is characterized in that the outer diameter of one end of an outer pipe (1) is upset and thickened, one end of the outer pipe (1) is sequentially provided with special fastening inner thread structures (5), the other end of the outer pipe (1) is provided with a special fastening outer thread structure (8), and the thermal-insulating oil pipes are directly connected to form a pipe column. By the arraignment, the direct connection type special-thread thermal-insulating oil pipe has the advantages that connection is performed by the threads at two ends of the outer pipe, the coupling connection of existing thermal-insulating oil pipes is avoided, structure simplification is achieved, and cost is reduced; wall thickness is increased, so that the tensile strength of the oil pipe is increased; sealing conical faces are disposed at the ends and tails of the threads, so that sealing performance is increased; by anti-torque shoulders, the compression resistance, the torque resistance and the thermal insulating effect of the oil pipe are increased greatly as compared with the prior art.

Description

technical field [0001] The invention relates to the technical field of heat-insulated oil pipes for thermal recovery wells in the petroleum industry, in particular to a direct-connection type special-threaded heat-insulated oil pipe. Background technique [0002] my country's heavy oil resources are widely distributed, and heavy oil accounts for a considerable proportion of my country's oil production, and the production of heavy oil in various oil fields is also increasing year by year. Heavy oil is mainly exploited by thermal extraction, which can be divided into steam huff and puff extraction, steam flooding, and steam-assisted gravity flooding. Affected by high temperature, the casing damage of thermal recovery wells is very serious. At present, most domestic heavy oil thermal recovery oil fields use heat-insulated tubing. The heat-insulated oil pipe is composed of inner and outer pipes. The outer pipe is connected to the inner pipe by welding. The inner and outer pipe...

AI Technical Summary

Problems solved by technology

The API (American Petroleum Institute) standard threaded joints used in large quantities in the past cannot meet the needs of oil and gas wells with harsh environmental conditions in terms of air tightness, connection strength and corrosion resistance, thus forcing people to research and develop special ones with more reliable performance. threaded joint

Images