CN-115573923-B - Binary channels hydraulic lift pump

CN115573923BCN 115573923 BCN115573923 BCN 115573923BCN-115573923-B

Abstract

The invention relates to a double-channel hydraulic lifting pump for solid fluidization exploitation of marine natural gas hydrate, which consists of a pump section, a turbine section, a bridge type channel assembly, an upper joint, a shell and a lower joint. The pump section mainly comprises a pump wheel, a guide wheel, a pump shaft, a pump shell and the like. The turbine section mainly comprises a stator, a rotor, a turbine shaft, a turbine shell and the like. The bridge type channel assembly mainly comprises a bridge type channel joint, a middle connecting shaft and a sealing assembly. The pump section and the turbine section are connected into a combined body through a bridge type channel assembly, and are centered in the middle of the shell by a centering block. When the turbine section works, the energy of the power fluid is converted into mechanical energy, the mechanical energy is transmitted to the pump shaft through the intermediate connecting shaft, the pump shaft drives the pump wheel to continuously suck the flowback fluid in the shaft, and the flowback fluid is discharged after acting. The invention controls and reduces the pressure of the shaft liquid column to the stratum in operation, solves the problem of shaft leakage in solid fluidization exploitation, and greatly improves the exploitation efficiency.

Inventors

GONG YAN
LIU YONGHONG
LIU PENG
XIN YONGLIANG

Assignees

中国石油大学(华东)

Dates

Publication Date: 20260505
Application Date: 20221013

Claims (2)

1. A double-channel hydraulic lifting pump is composed of a pump section, a turbine section, a bridge channel assembly, an upper joint (1), a shell (2) and a lower joint (36), and is characterized in that the pump section mainly consists of a pump wheel (9), a guide wheel (8), radial bearings (7 and 12), a thrust bearing group (13), a pump shaft (10), an upper joint (3) of a pump shell and a lower joint (14) of the pump shell, the turbine section mainly consists of a stator (30), a rotor (31), centering bearings (29 and 32), a thrust bearing (34), a turbine shaft (27), a turbine shell (28), a spline joint (26), an upper joint (25) of the turbine shell and a lower joint (35) of the turbine shell, the bridge channel assembly mainly consists of a bridge channel joint (16), an intermediate connecting shaft (15) and a sealing assembly, the pump section and the turbine section are connected into a combined body through the bridge channel assembly, wherein the pump shaft (10) is connected with the intermediate connecting shaft (15) through threads, the intermediate connecting shaft (15) is connected with the spline joint (26) through the spline joint, then the spline joint (26) is connected with the turbine shaft (27) through the threads into a whole, and simultaneously, the bridge channel assembly is connected with the pump shell (16) through the upper joint (25) and the lower joint (35) through the bridge channel joint (16), centralizing the assembly in the middle of the shell (2) by centralizing blocks (b and c) outside the pump shell (6) and centralizing blocks (d and e) outside the turbine shell (28), sitting on the lower joint (36) through a lower joint (35) of the turbine shell, and compacting the upper joint (3) of the pump shell by the upper joint (1) to realize the axial positioning of the assembly in the shell (2); The bridge type channel joint (16) is of a double-layer structure and consists of a middle pipe and a shell, five mutually independent flow channels (alpha, beta, gamma, delta and epsilon) are uniformly arranged in the circumferential direction of the bridge type channel joint, wherein two flow channels (gamma, epsilon) are used for conveying power fluid into a lower turbine section, the other three flow channels (alpha, beta and delta) are used for conveying flowback fluid of a pump section upwards, and the flow channels (gamma, epsilon) for conveying the power fluid are opposite to the flow channels (alpha, beta and delta) for conveying the flowback fluid in an inlet and outlet manner and are alternately arranged in the circumferential direction; The sealing assembly mainly comprises a gap sealing sleeve (24), che seals (21, 23), a spacer ring (22), a gland (18), an O-shaped ring (19), a wear-resistant ring (20) and screws (17), wherein the gap sealing sleeve (24) is arranged in a middle pipe of a bridge type channel joint (16) through threads, and a middle connecting shaft (15) penetrates through the center of the sealing assembly.
2. A dual channel hydraulic lift pump as claimed in claim 1 wherein the conical section of the turbine housing lower joint (35) sits on the conical surface of the lower joint (36), the key of the lower joint (36) snaps into the groove of the turbine housing lower joint (35).

Description

Binary channels hydraulic lift pump Technical Field The invention relates to a double-channel hydraulic lifting pump for solid fluidization exploitation of marine natural gas hydrate, belonging to the field of marine natural gas hydrate exploitation equipment. Background The solid state fluidization exploitation method of the marine natural gas hydrate is developed aiming at the problems of natural gas escape, easy collapse of stratum and the like in other exploitation methods, and adopts a rotary drilling method to mechanically crush the solid state natural gas hydrate in situ in a natural gas hydrate reservoir to form a pilot hole, and then adopts a high-pressure water jet mode to crush the solid state hydrate and mix the solid state hydrate with drilling fluid. And circulating the drilling fluid, and carrying the drilling fluid containing the hydrate solid-phase particles back to the sea surface from the sea floor, so as to realize green exploitation of the natural gas hydrate on the sea floor. However, due to the fact that the equivalent density window of the hydrate reservoir is narrow, the fracture pressure is low, stratum is extremely easy to leak, most drilling fluid pumped into the hydrate reservoir by the sea surface is leaked, and cannot return to the sea surface, and effective exploitation of the hydrate cannot be achieved. The method for reducing the pressure of the liquid column of the well bore on the hydrate reservoir and controlling the stratum leakage is an effective method for solving the problems. In a shaft of a submarine hydrate reservoir, a lifting pump is used for pumping, and drilling fluid containing hydrate solid-phase particles is conveyed to the sea surface in a pumping mode, so that the problem of leakage of the hydrate reservoir can be effectively solved, and the exploitation efficiency is improved. Disclosure of Invention The invention aims to meet the requirements of a solid-state fluidization exploitation process of marine natural gas hydrate, and provides a double-channel hydraulic lifting pump so as to realize green and efficient exploitation of the marine natural gas hydrate. The technical scheme adopted by the invention is as follows: The invention relates to a double-channel hydraulic lifting pump which consists of a pump section, a turbine section, a bridge type channel assembly, an upper connector, a shell and a lower connector. The pump section mainly comprises a pump wheel, a guide wheel, a radial bearing, a thrust bearing group, a pump shaft, a pump shell upper joint, a pump shell lower joint, a compression nut, an overcurrent sleeve, a stop pin and the like. The pump wheels are sleeved on the pump shaft through clearance fit, a plurality of pump wheels are arranged on the pump shaft for meeting different head demands, and the guide wheels are arranged behind each pump wheel, alternately arranged with the pump wheels and connected in series to form a pump. The pump wheel drives the flow-back fluid in the flow channel to move, does work on the flow-back fluid, converts mechanical energy into energy of the flow-back fluid, enters the guide wheel after being discharged by the pump wheel, decelerates in the flow channel of the guide wheel, changes the flow direction, then enters the pump wheel at the next stage with proper speed and direction, the energy is further increased, enters the subsequent pump wheel and the guide wheel again after being subjected to deceleration guiding of the guide wheel at the next stage, and flows out of the pump section after the energy of the flow-back fluid is increased to corresponding requirements until the guide wheel at the last stage. Radial bearings are arranged at two ends of the pump shaft to centralize the pump shaft, so that the pump shaft is not eccentric when rotating. The thrust bearing group is arranged at the lowest end of the pump shaft and is used for bearing the axial load generated by the pump wheel during operation and transmitting the axial load to the pump shell. The lower section of the pump shaft is hollow, the length of the hollow section extends upwards to the lower end of the suction inlet of the pump wheel in the pump shaft, grooves are uniformly distributed on the top end of the hollow section corresponding to the pump shaft along the circumferential direction, and a through flow channel is formed, so that flow-back fluid at the lower end of the pump shaft can smoothly enter the pump wheel through the hollow section of the pump shaft. The upper joint of the pump shell, the lower joint of the pump shell and the pump shell are all connected by screw threads, and parts of the pump section are fixed in the pump shell. The outer wall of the pump shell is provided with centering blocks which are uniformly distributed along the circumference corresponding to the position for placing the radial bearing. The turbine section mainly comprises a stator, a rotor, a centralizing bearing, a thrust bearing, a turbine shaft,