Expansion sleeve joint with double hook shaped thread connection

Abstract

The invention relates to an expansion sleeve joint with double hook shaped thread connection for the connection of integral joint expansion sleeves in oil and gas well engineering. Two-end structures of a male thread joint and a female thread joint correspondingly form sealed cabins, the sealed cabins are sealed by two fastened and inversely fastened bowl shaped rubber obturating rings, the deflection angle of a first hook surface of a hook shaped contact surface correspondingly formed by a single hook shaped thread of the male thread joint and a single hook shaped thread groove of the female thread joint is 15 DEG, the deflection angle of a second hook surface is 28 DEG, the height of the second hook surface is 25 to 30 percent of that of the thread, the rounding radius between the first hook surface and the second hook surface is 0.5 mm, the deflection angle of the reverse side of the thread is 5 DEG, the conicity of the thread is 1:23-1:25, and a hook tip of a second hook of the thread has an arc surface. The expansion sleeve joint has the close occlusion of double hook shaped internal and external threads, eliminates stress concentration, has high strength, has double hook shaped multiple metal-metal sealing and metal-rubber-metal sealing, and has the characteristics of integral sealing, strength uniformity of an expansion joint and the like.

Description

technical field [0001] The invention relates to a double-hook-shaped threaded expansion casing joint connected by expansion casings without couplings in oil and gas well engineering. Background technique [0002] Expandable casing technology will become one of the technologies that play a key role in the oil drilling and production industry in the 21st century. It is mainly used in many fields such as drilling, plugging complex formations, liner hanger and casing repair. Formation capacity, improve drilling efficiency and reduce drilling costs. Expandable casing technology is a new drilling technology that expands the pipe string radially to the plastic deformation area in the wellbore to achieve the purpose of "saving" the borehole diameter. Eventure company took the lead in the research of this technology in the world at the end of 1980s, and reached the level of commercial application in 1999. Enventure has obtained 600 patents and pending patents on expansion sleeves,...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to overcome the technical defect that the conventional API casing threads cannot meet the technical defects of maintaining the sealing and integrity of the threaded connection when directly processing on the expansion casing with no coupling and thinner wall thickness for expansion operations. The finite element simulation technology of the linear elastic-plastic thread contact problem and the nonlinear hyperelastic rubber-metal surface contact problem provides a double-hook threaded joint with good sealing integrity and uniform expansion strength for the expansion sleeve

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