RU2290539C2 - Submersible screw pump relief unit - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention can be used in production of equipment for recovery of high-viscosity oil. Proposed relief unit for submersible screw pumps has housing, and shaft with fitted-on support members. Unit includes sealed chamber filled with hydraulic oil with system of check valves and diaphragm used to equalize pressure inside chamber with pressure of formation fluid. Support members are made in form of axial thrust bearings arranged in sealed chamber provided with adjusting screws for uniform distribution of axial load. Said unit can take up and dampen axial loads directed to opposite sides.

EFFECT: improved reliability is service.

1 dwg

Description

The invention relates to mechanical engineering and can be used in the manufacture of equipment for the production of highly viscous oil.

Known submersible pump installation containing a submersible screw pump connected to the engine through a gearbox, filter and support and sealing assembly with a thrust bearing (RU 2059112 C1, 04/27/1996, F 04 C 29/00).

The disadvantage of this installation is that the presence of two pipe columns - an elevator and transmitting torque - complicates the installation of the installation in the well and does not provide sufficient reliability of the installation.

The design with submersible drive is deprived of these shortcomings (Well pumping units for oil production, Moscow, Oil and Gas, Russian State University of Oil and Gas named after IM Gubkin, 2002, p. 389). When using a submersible drive, the axial forces transmitted by the screw pump have a destructive effect on the heel of the hydraulic protection of the electric motor. To neutralize them, special designs of support nodes are used.

Known unloading unit containing a housing, a shaft with support elements placed on it (RU 2235226 C2, 04/10/2004, F 16 C 17/26).

The disadvantage of this design of the support node can be considered low reliability in the perception of axial loads created by a screw pump, since its support elements are in contact with the reservoir fluid, which also adversely affects the operation of the device.

An object of the invention is to provide a device design capable of absorbing and absorbing axial loads directed in opposite directions to both the base and the head of the unloading unit.

This problem is solved in that in the unloading unit for submersible screw pumps, comprising a housing, a shaft with supporting elements disposed thereon, according to the invention, the unit is equipped with a sealed chamber filled with hydraulic oil, with a check valve system and a diaphragm, which serves to equalize the pressure inside the chamber with the pressure of the reservoir fluid, while the supporting elements are made in the form of axial thrust bearings located in a sealed chamber, with adjusting screws that ensure uniform distribution axial load.

The drawing shows a discharge unit for submersible screw pumps.

The unloading unit includes a housing 1, a sealed chamber with interconnecting cavities 2, 3 filled with hydraulic oil, which provides cooling and lubrication of the radial bearings 4 of the shaft 5, sliding bearings 6 of the shaft 7, as well as the main supporting elements. The tightness of the chamber is ensured by mechanical seals 8, a system of valves 9 and a diaphragm 10, which also serves to equalize the pressure inside the cavity 2 with the pressure of the reservoir fluid. The valves 9 located in the upper part of the chamber also allow for the release of excess oil during thermal expansion of the diaphragm 10. The support elements are made in the form of axial thrust bearings 11, 12, 13 located in the lower part of the chamber and providing perception of axial loads. They are equipped with adjusting screws 14, 15, tightening which ensures uniform distribution of loads from the screw pump (not shown in the drawing). The shafts 5, 7 are rigidly articulated with a coupling 16 with pins 17.

When starting the electric motor (not shown in the drawing), the torque is transmitted through the shafts 7, 5 to the screw pump. In this case, radial loads are perceived and absorbed by bearings 6, 4, and axial loads directed downward to the electric motor, from the screw pump through the shaft end 5 along the thrust bushings on the shaft 7, are absorbed and absorbed by bearings 12, 13, and upward loads by the bearing 11. In this case, the axial loads through the bearings 11, 12, 13 and the adjusting screws 14, 15 are transferred to the housing 1 and are quenched by it.

Claims (1)

An unloading unit for submersible screw pumps, comprising a housing, a shaft with supporting elements placed on it, characterized in that the assembly is equipped with a sealed chamber filled with hydraulic oil, with a check valve system and a diaphragm, which serves to equalize the pressure inside the chamber with the pressure of the reservoir fluid, this supporting elements are made in the form of axial thrust bearings located in a sealed chamber, with adjusting screws that ensure uniform distribution of axial load.