Low-stress threaded connection structure

Abstract

The invention discloses a low-stress threaded connection structure. The low-stress threaded connection structure comprises an outer threaded part and an inner threaded part, the outer threaded part isprovided with an outer thread, the inner threaded part is provided with an inner thread, and the outer thread and the inner thread are engaged with each other in a screwed state; the guide surface ofthe inner thread is composed of an upper half-section inclined surface and a lower half-section inclined surface, the inclination angle of the upper half-section inclined surface is beta, the inclination angle of the lower half-section inclined surface is gamma, and beta is smaller than gamma; and the guide surface, corresponding to the guide surface of the inner thread, of the outer thread is aninclined surface with the inclination angle of beta. The lower half-section inclined surface of the guide surface of the inner thread is smooth so that buckle aligning can be convenient, and the upper half-section inclined surface of the guide surface of the inner thread is steep, so that the thread has good compression resistance; and the guide surface of the outer thread corresponding to the inner thread is only provided with one section with the inclination angle of beta so that buckle aligning can be convenient and buckle staggering is not liable to occur during buckling, stress concentration is not liable to occur on the guide surfaces, and thus the guide surfaces are prevented from being stuck.

Description

technical field [0001] The invention relates to a low-stress thread connection structure, which belongs to the technical field of oil casing thread connection. Background technique [0002] With the development of the country's economy, the demand for oil and natural gas is increasing, the depth of oil and gas wells drilled is getting deeper and deeper, and the stratum structure encountered is becoming more and more complex. Tubes and drill pipes, etc.) have higher and higher requirements, which are mainly reflected in the material properties of mining tools and the quality requirements of threaded connections: for materials, it is mainly to develop high-strength, corrosion-resistant, high-temperature-resistant materials, and for connecting threads. In other words, it is necessary to continuously develop high-quality joints with high connection efficiency, good sealing performance, strong torsion resistance, and repeated loading and unloading. [0003] For deep and ultra-de...

AI Technical Summary

Problems solved by technology

The disadvantage is that the guide surface is too flat, although the anti-sticking ability of the joint is improved, but the anti-compression performance of the joint will be reduced

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