Electric submersible pump spline coupling structure for integrated well

Abstract

The invention discloses an electric submersible pump spline coupling structure for an integrated well, which comprises a motor output spline shaft end, a water pump input hexagonal shaft end and a coupling, wherein the coupling is provided with an upper half-coupling and a lower half-coupling; the upper half-coupling is a lug-bearing flange and is provided with a central threaded shaft hole, a connecting bolt hole and a counterbore; the lower half-coupling is a lug-bearing cylinder, the lug edge is provided with a notch, and the cylinder is provided with a central shaft hole and a spline hole; the tail end of the spline section of the motor output spline shaft end is provided with a thread; the upper half-coupling is connected to the thread; the end part of the water pump input hexagonal shaft end forms an interference connection with the lower half-coupling; the spline section is connected with the spline hole; the lug is arranged in the counterbore, sheathed into the lower half-coupling through a positioning connecting ring of which the inner ring edge is provided with a convex tongue and connected to the upper half-coupling; and the packaging lug is arranged in the counterbore, and the convex tongue is arranged in the lug notch, so that the upper half-coupling and the lower half-coupling are connected together. The electric submersible pump spline coupling structure ensures the coaxiality and strength, prevents inversion and come-off, lowers the processing cost, and is simple in mounting technique.

Description

technical field [0001] The invention relates to a shaft coupling structure in which a motor shaft of a well submersible pump and a water pump shaft are connected together, in particular to an integrated spline coupling structure of a submersible electric pump for well use. Background technique [0002] In the prior art, the coupling structure in which the motor shaft of the well submersible pump and the water pump shaft are connected together is usually connected by a coupling, and some are connected by welding or threaded direct connection, especially the integrated submersible pump for wells. The internal structure includes the motor and the multi-stage water pump impeller group. The two are connected together by the internal coupling structure. The output shaft of the motor is a cylindrical shaft, and its shaft head is usually processed as a flat key shaft or a spline shaft or a threaded shaft. The water pump shaft is Hexagonal shaft, when the two are connected, it is nec...

AI Technical Summary

Problems solved by technology

[0002] In the prior art, the coupling structure in which the motor shaft of the well submersible pump and the water pump shaft are connected together is usually connected by a coupling, and some are connected by welding or threaded direct connection, especially the integrated submersible pump for wells. The internal structure includes the motor and the multi-stage water pump impeller group. The two are connected together by the internal coupling structure. The output shaft of the motor is a cylindrical shaft, and its shaft head is usually processed as a flat key shaft or a spline shaft or a threaded shaft. The water pump shaft is Hexagonal shaft, when the two are connected, it is necessary to ensure the coaxiality to meet the dynamic balance requirements, otherwise the submersible pump will vibrate during operation and generate large noise, which may easily cause submersible pump failure; the internal coupling structure is an integrated well submersible The key structure of the electric pump, the hexagonal shaft of the water pump is positioned and connected by the coupling. The coaxiality between the two shafts affects the product quality and life; the coupling method is to set different ends of the coupling. Shaft hole, one end is a hexagonal shaft hole, connected to the hexagonal shaft of the water pump, one end is a spline hole or a flat key hole, connected with the motor output shaft by a spline or a flat key, the coupling can be forged or machined, to ensure Coaxiality, its processing difficulty and cost are high, and the welding method requires welding joint processing and straightening procedures after welding. The processing cost is high and the processing efficiency is low. The long shaft after welding makes the motor installation and The installation process of the water pump is complicated. The threaded direct connection means that the motor output shaft has an external threaded shaft end, and the hexagonal shaft end of the water pump has a threaded hole for direct threaded connection. This structure also has the problem of coaxiality that is difficult to guarantee, and at the same time reduces the connection. The strength of the position, but in order to ensure the strength, the diameter of the hexagonal shaft must be increased, and the material cost will increase, and this structure is not suitable for the connection of three-phase motors, because there is a phenomenon of reverse loosening, which will cause water pump failure repeatedly, so None of the above structures can ensure coaxiality while ensuring strength and reducing processing costs

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