Stator for screw drills and machining process of stator

Abstract

The invention relates to a stator for screw drills and a machining process of the stator. A stator body and a convex helicoid are integrated, thereby greatly improving the strength of the stator; steel balls are arranged in the stator body and the convex helicoid, the steel balls are subjected to pile-up welding to be connected to form a whole body, thereby further increasing the strength of the stator; a rubber layer is firmly connected with the convex helicoid, and the deformation of a rubber layer subjected to stressing is uniform, and therefore, the deformation-resistant performance of the rubber layer is strong; and the heat dissipation performance and sealing performance of the stator are improved, thereby improving the operating efficiency and service life of the screw drill. The stator body and the convex helicoid are directly cast by using aluminum water, and therefore, the machining process of the stator is simple; the convex helicoid is machined without machining, so that the machining difficulty of convex helicoids of stators which are equal in wall thickness is greatly reduced, thereby greatly reducing the production cost of the stator.

Description

technical field [0001] The invention relates to a device for oil drilling, in particular to a stator for a screw drilling tool and its processing technology. Background technique [0002] The screw drilling tool is a downhole dynamic drilling tool commonly used in petroleum and natural gas drilling engineering. The screw drilling tool is composed of two basic parts: the rotor and the stator. The stator currently used is composed of a stator housing and a rubber bushing. The inner cavity of the stator housing is a smooth cylindrical surface. The rubber is bonded to the inner wall of the stator housing through a vulcanization process. A convex helicoid forms a continuous helical surface. During the working process, due to the periodic extrusion of the rotor and the pressure difference between the stator and rotor seal chamber, the rubber bush will be deformed unevenly due to the unequal wall thickness of the rubber bush, which will lead to the weakening of the mechanical seal...

AI Technical Summary

Problems solved by technology

During the working process, due to the periodic extrusion of the rotor and the pressure difference of the stator and rotor seal chamber, the rubber bush will be deformed unevenly due to the uneven wall thickness of the rubber bush, which will lead to the weakening of the mechanical sealing performance of the rubber bush, and at the same time Due to the uneven heat dissipation of the rubber bushing, the thermal hysteresis is serious, which makes the rubber easy to age and tear, shortening its service life

[0003] In order to improve the service life of the rubber bushing in the stator, stators for screw drilling tools with equal wall thickness have appeared at home and abroad. Because the wall thickness of the stator rubber bushing is the same, the rubber bushing deforms evenly after being stressed, has strong deformation resistance, and dissipates heat. The performance and sealing performance are improved, which improves the working efficiency and service life of the screw drilling tool, but the inner surface of the constant-wall-thickness stator shell is a continuous spiral curved surface, which is difficult to process, complex in processing technology, and high in processing cost

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