A fracturing pump plunger sealing device

Abstract

A fracturing pump plunger sealing device relates to the technical field of fracturing pumps. A piston sleeve is installed in a step hole B, a gland is installed on the outside of the piston sleeve, a support sleeve is processed on the inside of the gland, and a step shaft is processed on the outside of the support sleeve. The step shaft is connected to the step hole B through a sealing ring gap fit, and the piston sleeve is connected to the support sleeve and the step hole B through a sealing ring gap fit. The beneficial effect of the present invention is that when the fracturing pump is discharging liquid under high pressure, the high-pressure liquid acts on the inside of the seal from the pump body on the one hand, and the high-pressure liquid acts on the piston sleeve through the horizontal counterbore, the vertical hole and the step hole B on the other hand. The piston sleeve moves to the outside of the seal under the action of the high-pressure liquid. The pressure on both sides of the seal can be balanced by calculation. When the pump body absorbs liquid, both sides of the seal are not subjected to pressure, which reduces the wear of the seal and the plunger, thereby reducing the possibility of liquid leakage from the seal during high-pressure discharge, increasing the service life of the seal, and reducing the replacement cycle of the seal.

Description

Technical Field

[0001] The present invention relates to the technical field of fracturing pumps, and in particular to a fracturing pump plunger sealing device. Background Art

[0002] During oil fracturing operations, the fracturing pump is the key core equipment. The reciprocating plunger in the fracturing pump adopts a plunger sealing device with multiple V-shaped sealing rings in series. The fracturing process requires the fracturing pump to have a large displacement and high pressure. The plunger seal pressure difference in the reciprocating motion of the fracturing pump is large and the working life is short, which seriously restricts the reliable operation of the fracturing pump. Summary of the invention

[0003] In order to solve the problems of short service life and poor reliability of the current fracturing pump plunger seal, the present invention provides a fracturing pump plunger seal device.

[0004] The technical solution provided by the present invention is: a fracturing pump plunger sealing device, including a pump body and a plunger, the pump body is provided with a transverse countersunk hole and a vertical hole inwardly, the transverse countersunk hole is connected with the discharge channel of the pump body, the transverse countersunk hole and the vertical hole are cross-connected, a through hole is provided in the pump body, the through hole is connected with the plunger through clearance, the pump body is provided with a step hole A and a step hole B on the outside of the through hole, the step hole B is larger than the step hole A, the step hole A is larger than the through hole, the pump body is threadedly sealed and connected with a plug B at the outer end face of the transverse countersunk hole, and the pump body is threadedly sealed and connected with a plug A at the outer end face of the vertical hole; A baffle B, a seal and a baffle A are installed in sequence from the inside to the outside between the step hole A and the plunger, a piston sleeve is installed in the step hole B, a pressure cover is installed on the outside of the piston sleeve, the pressure cover is connected to the pump body by bolts, a support sleeve is processed on the inside of the pressure cover, a step shaft is processed on the outside of the support sleeve, the outer diameter of the step shaft is larger than the support sleeve, the step shaft is connected to the step hole B through a sealing ring clearance fit, the piston sleeve, the support sleeve and the step hole B are connected through a sealing ring clearance fit, the inner side of the piston sleeve is against the baffle A, there is a space between the piston sleeve and the step shaft, and the vertical hole is connected to the step hole B through the space.

[0005] A floating piston is provided in the transverse counterbore. The floating piston is located in the hole after the transverse counterbore passes through the discharge channel. A limit hole is opened on the pump body between the floating piston and the discharge channel. The limit hole is vertically connected to the transverse counterbore. The limit hole thread seal is connected to the limit rod. The limit rod extends into the transverse counterbore. The limit rod is blocked on the outside of the floating piston. The space inside the floating piston, the vertical hole and the step hole B is filled with hydraulic oil.

[0006] A compression spring is arranged between the outer side of the piston sleeve and the end surface of the step shaft.

[0007] The beneficial effects of the present invention are as follows: by arranging a piston sleeve on the outside of the seal, the piston sleeve is connected to the step hole B and the support sleeve through a sealed movement, and the piston sleeve is connected to the discharge channel through a transverse countersunk hole and a vertical hole, so that when the fracturing pump is discharging liquid under high pressure, the high-pressure liquid acts on the inner side of the seal from the pump body on the one hand, and the high-pressure liquid acts on the piston sleeve through the transverse countersunk hole, the vertical hole and the step hole B on the other hand. The piston sleeve moves to the outside of the seal under the action of the high-pressure liquid, and the pressure on both sides of the seal can be balanced through calculation. When the pump body absorbs liquid, both sides of the seal are not subjected to pressure, which reduces the wear of the seal and the plunger, thereby reducing the possibility of liquid leakage from the seal during high-pressure discharge, increasing the service life of the seal, and reducing the seal replacement cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Attached Figure 1 It is a schematic diagram of the structure of the present invention; Attached Figure 2 Yes Figure 1 A magnified image of point A; Attached Figure 3 It is a schematic diagram of the structure of the pump body in the present invention; Attached Figure 4 It is a structural schematic diagram of the gland in the present invention.

[0009] In the figure, 1- pump body, 2- plunger, 3- seal, 4- piston sleeve, 5- gland, 6- transverse countersunk hole, 7- vertical hole, 8- thread plug A, 9- thread plug B, 10- discharge channel, 11- floating piston, 12- limit hole, 13- limit rod, 14- through hole, 15- step hole A, 16- step hole B, 17- baffle A, 18- baffle B, 19- compression spring, 20- support sleeve, 21- step shaft. DETAILED DESCRIPTION

[0010] like Figures 1 to 4 As shown, a fracturing pump plunger sealing device includes a pump body 1 and a plunger 2. The pump body 1 is provided with a transverse counterbore 6 and a vertical hole 7 inwardly, the transverse counterbore 6 is connected with a discharge channel 10 of the pump body 1, and the transverse counterbore 6 crosses and connects with the vertical hole 7. A through hole 14 is provided in the pump body 1, and the through hole 14 is connected with the plunger 2 in a clearance fit. The pump body 1 is provided with a step hole A15 and a step hole B16 on the outside of the through hole 14, respectively. The step hole B16 is larger than the step hole A15, and the step hole A15 is larger than the through hole 14. The pump body 1 is threadedly sealed at the outer end surface of the transverse counterbore 6 to connect with a thread plug B9, and the pump body 1 is threadedly sealed at the outer end surface of the vertical hole 7 to connect with a thread plug A8; Baffle B18, seal 3 and baffle A17 are installed in sequence from inside to outside between step hole A15 and plunger 2, piston sleeve 4 is installed in step hole B16, pressure cover 5 is installed on the outside of piston sleeve 4, pressure cover 5 is connected to pump body 1 by bolts, support sleeve 20 is processed on the inner side of pressure cover 5, step shaft 21 is processed on the outside of support sleeve 20 of pressure cover 5, the outer diameter of step shaft 21 is larger than that of support sleeve 20, step shaft 21 is connected with step hole B16 through sealing ring clearance fit, piston sleeve 4 is connected with support sleeve 20 and step hole B16 through sealing ring clearance fit, the inner side of piston sleeve 4 is against baffle A17, there is a space between piston sleeve 4 and step shaft 21, vertical hole 7 is connected with step hole B16 through this space.

[0011] By arranging a piston sleeve 4 on the outside of the seal 3, the piston sleeve 4 is connected to the step hole B16 and the support sleeve 20 through a sealed movement, and the piston sleeve 4 is connected to the discharge channel 10 through the transverse countersunk hole 6 and the vertical hole 7, so that when the fracturing pump is discharged under high pressure, the high-pressure liquid acts on the inner side of the seal 3 from the pump body 1 on the one hand, and the high-pressure liquid acts on the piston sleeve 4 through the transverse countersunk hole 6, the vertical hole 7 and the step hole B16 on the other hand. The piston sleeve 4 moves to the outside of the seal 3 under the action of the high-pressure liquid. The pressure on both sides of the seal 3 can be balanced through calculation. When the pump body 1 absorbs liquid, the pressure on both sides of the seal 3 is not maintained, which reduces the wear of the seal 3 and the plunger 2, thereby reducing the possibility of liquid leakage from the seal 3 during high-pressure discharge, increasing the service life of the seal 3, and reducing the replacement cycle of the seal 3.

[0012] A floating piston 11 is provided in the transverse counterbore 6. The floating piston 11 is located in the hole after the transverse counterbore 6 passes through the discharge channel 10. A limiting hole 12 is opened on the pump body 1 between the floating piston 11 and the discharge channel 10. The limiting hole 12 is vertically connected to the transverse counterbore 6. The limiting hole 12 is threadedly sealed and connected to a limiting rod 13. The limiting rod 13 extends into the transverse counterbore 6. The limiting rod 13 blocks the outside of the floating piston 11. The space inside the floating piston 11, the vertical hole 7 and the step hole B16 is filled with hydraulic oil. The high-pressure liquid transmits the hydraulic pressure to the piston sleeve 4 through the floating piston 11, which is beneficial to the operating environment of the piston sleeve 4 and improves its service life.

[0013] A compression spring 19 is provided between the outer side of the piston sleeve 4 and the end surface of the step shaft 21 to provide a pre-tightening force to the sealing member 3 .

Claims

1. A fracturing pump plunger sealing device, comprising a pump body (1) and a plunger (2), characterized in that: The pump body (1) is provided with a transverse counterbore (6) and a vertical hole (7) inwardly, the transverse counterbore (6) is connected with the discharge passage (10) of the pump body (1), the transverse counterbore (6) and the vertical hole (7) are cross-connected, a through hole (14) is provided in the pump body (1), the through hole (14) is connected with the plunger (2) by clearance fit, the pump body (1) is provided with a step hole A (15) and a step hole B (16) on the outside of the through hole (14), the step hole B (16) is larger than the step hole A (15), the step hole A (15) is larger than the through hole (14), the pump body (1) is provided with a threaded sealing connection thread plug B (9) at the outer end surface of the transverse counterbore (6), and the pump body (1) is provided with a threaded sealing connection thread plug A (8) at the outer end surface of the vertical hole (7); A baffle plate B (18), a sealing member (3) and a baffle plate A (17) are installed in sequence from the inside to the outside between the step hole A (15) and the plunger (2); a piston sleeve (4) is installed in the step hole B (16); a gland (5) is installed on the outside of the piston sleeve (4); the gland (5) is connected to the pump body (1) by bolts; a support sleeve (20) is processed on the inside of the gland (5); a step shaft (21) is processed on the outside of the support sleeve (20) of the gland (5); the outer diameter of the step shaft (21) is larger than that of the support sleeve (20); the step shaft (21) is connected to the step hole B (16) by a sealing ring clearance fit; the piston sleeve (4) is connected to the support sleeve (20) and the step hole B (16) by a sealing ring clearance fit; the inner side of the piston sleeve (4) abuts against the baffle plate A (17); there is a space between the piston sleeve (4) and the step shaft (21); the vertical hole (7) is connected to the step hole B (16) through the space.

2. A fracturing pump plunger sealing device according to claim 1, characterized in that: A floating piston (11) is arranged in the transverse counterbore (6). The floating piston (11) is located in a hole after the transverse counterbore (6) passes through the discharge channel (10). A limiting hole (12) is opened in the pump body (1) between the floating piston (11) and the discharge channel (10). The limiting hole (12) is vertically connected to the transverse counterbore (6). The limiting hole (12) is threadedly sealed and connected to a limiting rod (13). The limiting rod (13) extends into the transverse counterbore (6). The limiting rod (13) is blocked on the outside of the floating piston (11). The space inside the floating piston (11), the vertical hole (7) and the step hole B (16) is filled with hydraulic oil.

3. A fracturing pump plunger sealing device according to claim 1, characterized in that: A compression spring (19) is provided between the outer side of the piston sleeve (4) and the end surface of the step shaft (21).

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