Displacement variable oil-well pump

Abstract

The invention relates to a displacement variable oil-well pump. A pump cylinder, a connecting pipe, an oil inlet valve and a small pump are sequentially connected; a large plunger, an oil outlet valve and an uncoupling device are sequentially connected, an oil inlet is arranged between the oil outlet valve and an upper body of the uncoupling device, the diameter of the upper body of the uncoupling device is less than the internal diameter of the large pump cylinder, the inner diameter of the connecting pipe is more than that of the large pump cylinder to ensure that the joint of the lower part of the large pump cylinder and the upper part of the connecting pipe generates a releasing ledge, and the upper body of the uncoupling device and the lower body of the uncoupling device can be separated at the releasing ledge. Due to the combination of the large cylinder and the connecting pipe, a releasing ledge of the uncoupling device is formed, and the displacement of the oil-well pump can be changed by adopting the common uncoupling device; because the outer diameter of the lower body of the common uncoupling device is more than the internal diameter of the releasing ledge, only the uncoupling device is released after lifted to the releasing ledge, and the uncoupling device can be released as long as being lifted to the releasing ledge. The invention can be used for reliably changing the displacement and prolonging the oil well production period, and has remarkable economic benefit.

Description

technical field [0001] The invention belongs to equipment for oil pumping in oil fields, in particular to a variable displacement oil pump. Background technique [0002] Some pumping wells have high liquid production and low crude oil viscosity at the beginning of pumping, such as heavy oil wells exploited after steam huffing and puffing, which require large-scale production. Since the crude oil viscosity is low at the initial stage of pumping, there is no need for the pump to have feedback force to help When the oil pump goes down, the liquid production rate decreases in the later stage of well opening, and the viscosity of crude oil increases. The displacement of the oil pump needs to be reduced, and the feedback force of the oil well pump is also required to help it go down. Ordinary oil well pumps cannot adapt to this change and requirement. . Chinese patent application 89206034.4 "Variable Displacement Viscous Oil Pump" is designed for this requirement, because its des...

AI Technical Summary

Problems solved by technology

[0002] Some pumping wells have high liquid production and low crude oil viscosity at the beginning of pumping, such as heavy oil wells exploited after steam huffing and puffing, which require large-scale production. Since the crude oil viscosity is low at the initial stage of pumping, there is no need for the pump to have feedback force to help When the oil pump goes down, the liquid production rate decreases in the later stage of well opening, and the viscosity of crude oil increases. The displacement of the oil pump needs to be reduced, and the feedback force of the oil well pump is also required to help it go down. Ordinary oil well pumps cannot adapt to this change and requirement.

Chinese patent application 89206034.4 "Variable Displacement Viscous Oil Pump" is designed for this requirement, because its design scheme can not adopt the disconnecting device commonly used, have to design a set of disconnecting device (6) specially, in order to adapt to the requirements of the invention, this The sleeve disconnecting device is disconnected and connected at the lower starting point, and the connection and connection are realized by touching the pump alternately. This disconnection method is not easy to complete correctly on site, because the length of the sucker rod must be adjusted many times before pumping to meet the requirements. The matching length between the upper part of the sucker rod and the wellhead, the operator sometimes misremembers the adjustment and the number of pump touches, and cannot accurately know whether the disconnecting device is disconnected or connected, so that the oil well cannot be produced accurately as expected, and the production data after the subsequent well is opened There are also great deficiencies in the method of analyzing and judging the state of the tripping device.

Moreover, it is impossible for all disconnecting devices to be connected in one docking operation. Sometimes multiple contacts are required to successfully connect, and the disconnecting method of the disconnecting device in the Chinese patent application 89206034.4 "Variable Displacement Heavy Oil Pump" is also impossible to disconnect at one time. Sexual manipulation can get rid of

Therefore, variable displacement pumping technology has poor reliability and cannot meet the needs of heavy oil wells exploited after steam huffing and puffing

Images