Packing-free fluid end

Abstract

The packing-free fluid end comprises a pump head, a pressure relief sleeve and a plunger, the pump head is provided with a working cavity, the pressure relief sleeve is connected to the pump head, the pressure relief sleeve communicates with the working cavity, the pressure relief sleeve is provided with a pressure relief hole, the pressure relief hole penetrates through the pressure relief sleeve, and the plunger is arranged in the working cavity. One end of the plunger penetrates through the pressure relief sleeve and then is embedded in the working cavity in a sliding mode, and the plunger is in clearance fit with the side wall of the working cavity. The plunger is in clearance fit with the side wall of the working cavity, so that frictional wear between the plunger and the working cavity is reduced; meanwhile, under the condition that the plunger goes deep into the working cavity to output high-pressure water, trace high-pressure water permeates into the space between the plunger and the side wall of the working cavity and flows to the space between the plunger and the pressure relief sleeve, the trace high-pressure water releases pressure at the pressure relief hole to become low-pressure water, high-pressure leakage is avoided, and the plunger is cooled.

Description

Technical Field

[0001] The present application relates to the field of plunger pumps, and in particular to a filler-free hydraulic end. Background Art

[0002] The existing document with announcement number CN207297326U discloses a high-pressure plunger pump, including a crankcase and a pump head. A working chamber is arranged in the pump head. The tail of the plunger is connected to the crankshaft by transmission, and a ceramic tube is coaxially fixed to the head. A sealing assembly is arranged on the outer periphery of the ceramic tube, and the sealing assembly is sealed at one end of the working chamber.

[0003] During the operation of the plunger pump, the plunger (ceramic tube) and the sealing assembly rub against each other. When the wear of the sealing assembly reaches the specified value, the sealing assembly needs to be replaced. Summary of the invention

[0004] In order to facilitate maintenance, the present application provides a packing-free hydraulic end.

[0005] The present application provides a packing-free hydraulic end adopting the following technical solution: A packing-free hydraulic end comprises a pump head, a pressure relief sleeve and a plunger. The pump head is provided with a working chamber. The pressure relief sleeve is connected to the pump head, the pressure relief sleeve is connected to the working chamber, and the pressure relief sleeve is provided with a pressure relief hole, and the pressure relief hole passes through the pressure relief sleeve. One end of the plunger passes through the pressure relief sleeve and is slidably embedded in the working chamber, and there is clearance fit between the plunger and the side wall of the working chamber.

[0006] By adopting the above technical solution, the clearance between the plunger and the side wall of the working chamber is matched to reduce the friction and wear between the two; at the same time, when the plunger penetrates deep into the working chamber to output high-pressure water, a small amount of high-pressure water penetrates between the plunger and the side wall of the working chamber, and a small amount of high-pressure water flows between the plunger and the pressure relief sleeve. The small amount of high-pressure water releases the pressure at the pressure relief hole and becomes low-pressure water, thereby avoiding high-pressure leakage and cooling the plunger.

[0007] Preferably, the cylinder body is provided with a cooling channel. The pressure relief hole is connected to the cooling channel.

[0008] By adopting the above technical solution, low-pressure water directly flows into the cooling channel to avoid wanton leakage, so that the hydraulic end remains clean.

[0009] Preferably, the pressure relief sleeve is provided with a micro-slowing hole, the micro-slowing hole penetrates the pressure relief sleeve, and the micro-slowing hole is located on the side of the pressure relief hole away from the working chamber.

[0010] By adopting the above technical solution, the micro-slow hole is a backup design. Under normal circumstances, high-pressure water releases pressure at the pressure relief hole. Under abnormal circumstances, if the pressure at the pressure relief hole is not completely released, the pressure is further released at the micro-slow hole.

[0011] Preferably, the pressure relief sleeve and the plunger are clearance-fitted, and the pressure relief sleeve and the pump head are clearance-fitted.

[0012] By adopting the above technical solution, the clearance fit reduces friction, and the clearance allows water to penetrate and buffer the water pressure.

[0013] Preferably, it further comprises a sealing ring, wherein the sealing ring fits the plunger, the sealing ring fits the pump head, and the sealing ring is located on a side of the pressure relief sleeve away from the working chamber.

[0014] By adopting the above technical solution, leakage of low-pressure water can be avoided.

[0015] Preferably, a buffer hole is provided on the side wall of the working chamber.

[0016] By adopting the above technical solution, the water pressure is first buffered by the buffer hole, and then the water pressure is reduced by the pressure relief hole, thereby releasing the pressure in multiple stages.

[0017] Preferably, the pump body comprises a main body and a bushing. The bushing is embedded in the main body, and the bushing forms the working chamber. The buffer hole passes through the inner and outer circumferences of the bushing.

[0018] By adopting the above technical solution, the bushing can be made of wear-resistant material.

[0019] Preferably, it also includes a connecting shaft, a connecting piece, an assembly piece, a clamp and an elastic piece. The connecting member is connected to the outer periphery of the connecting shaft. The assembly is connected to the outer periphery of the other end of the plunger. The clamp is provided with an embedding groove. The connecting piece, the assembling piece and the elastic piece are all embedded in the embedding groove.

[0020] By adopting the above technical solution, the side wall of the working chamber and the plunger are in hard contact. When there is a small angle between the connecting shaft and the axis of the working chamber, the elastic deformation of the elastic member is used to compensate, thereby ensuring that the plunger can move back and forth.

[0021] Preferably, it also includes a retaining spring, The clamp is in the shape of a fan ring, the central angle of the clamp is an obtuse angle or a straight angle, the clamp is provided with a clamping groove, and the clamp is provided with two, The clamping spring is sleeved outside the clamping hoop, and the clamping spring is embedded in the clamping groove.

[0022] By adopting the above technical solution, axial and radial limiting of the connecting shaft and the assembly parts can be achieved.

[0023] In summary, the present application includes at least one of the following beneficial technical effects: 1. The clearance between the plunger and the side wall of the working chamber is matched to reduce the friction and wear between the two. At the same time, when the plunger goes deep into the working chamber to output high-pressure water, a small amount of high-pressure water penetrates between the plunger and the side wall of the working chamber, and a small amount of high-pressure water flows between the plunger and the pressure relief sleeve. The small amount of high-pressure water releases pressure at the pressure relief hole and becomes low-pressure water, avoiding high-pressure leakage and cooling the plunger. 2. Low-pressure water flows directly into the cooling channel to avoid leakage and keep the hydraulic end clean; 3. There is hard contact between the side wall of the working chamber and the plunger. When there is a small angle between the connecting shaft and the axis of the working chamber, the elastic deformation of the elastic part is used to compensate and ensure that the plunger can move back and forth. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the fluid end without packing.

[0025] Figure 2 It is a cross-sectional schematic diagram of the fluid end without packing.

[0026] Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0027] Figure 4 It is a schematic diagram of the cylinder body.

[0028] Figure 5 It is a cross-sectional schematic diagram of the connecting shaft and assembly parts.

[0029] Explanation of the reference numerals in the accompanying drawings: 1. Pump head; 11. Main body; 12. Cylinder body; 121. Pressure relief groove; 122. Cooling channel; 123. Connecting hole; 13. Bushing; 131. Buffer hole; 2. Plunger; 3. Pressure relief sleeve; 31. Pressure relief hole; 32. Micro-buffer hole; 4. Sealing ring; 51. Connecting shaft; 511. Groove; 52. Connecting piece; 6. Assembly piece; 61. Bucket; 62. Assembly ring; 7. Gasket; 81. Clamp; 811. Slot; 812. Embedded groove; 82. Retaining spring; 9. Elastic piece. DETAILED DESCRIPTION

[0030] The present application is further described in detail below in conjunction with the accompanying drawings.

[0031] Reference Figure 1 and Figure 2 The embodiment of the present application discloses a filler-free hydraulic end, including a pump head 1 and a plunger 2.

[0032] The pump head 1 includes a main body 11, a cylinder body 12 and a bushing 13. There are multiple cylinder bodies 12, and the cylinder bodies 12 are embedded in the main body 11. The bushings 13 and the cylinder bodies 12 correspond to each other one by one, and the bushings 13 are embedded in the cylinder bodies 12, and a working chamber is formed in the bushings 13. One end of the plunger 2 is embedded in the working chamber, and the plunger 2 and the bushing 13 are clearance-matched. In this embodiment: there are three cylinder bodies 12.

[0033] A buffer hole 131 is provided in the middle of the bushing 13 in the axial direction. A plurality of buffer holes 131 are provided at intervals along the circumference of the bushing 13. The buffer holes 131 penetrate the inner and outer circumferences of the bushing 13 in the radial direction. In this embodiment, four buffer holes 131 are provided.

[0034] When the plunger 2 penetrates deeply into the working chamber to output high-pressure water, a small amount of high-pressure water penetrates between the plunger 2 and the side wall of the working chamber, and the high-pressure water flows through the buffer hole 131 to buffer the water pressure.

[0035] Reference Figure 2 and Figure 3 The non-filled hydraulic end also includes a pressure relief sleeve 3. The pressure relief sleeve 3 is coaxially embedded in the cylinder body 12, and the pressure relief sleeve 3 abuts against the bushing 13. One end of the plunger 2 passes through the pressure relief sleeve 3 and extends into the bushing 13; and the pressure relief sleeve 3 and the plunger 2 have clearance fit, and the pressure relief sleeve 3 and the cylinder body 12 have clearance fit.

[0036] The pressure relief sleeve 3 is provided with a pressure relief hole 31 and a slow hole 32. In the axial direction, the slow hole 32 is located on the side of the pressure relief hole 31 away from the working chamber. The pressure relief hole 31 and the slow hole 32 both penetrate the inner and outer peripheries of the pressure relief sleeve 3 in the radial direction.

[0037] Reference Figure 3 and Figure 4 The cylinder body 12 is provided with a pressure relief groove 121 , a cooling channel 122 and a connecting hole 123 .

[0038] The pressure relief groove 121 is an annular groove, and the pressure relief groove 121 is directly opposite to the pressure relief hole 31. The communication hole 123 extends in the radial direction, and the communication hole 123 is connected to the cooling flow channel 122.

[0039] The non-filler hydraulic end further comprises a sealing ring 4. The sealing ring 4 fits the plunger 2, the sealing ring 4 fits the pump head 1, and the sealing ring 4 is located on the side of the pressure relief sleeve 3 away from the working chamber.

[0040] The high-pressure water flows to the pressure relief sleeve 3 , and the high-pressure water releases pressure at the pressure relief hole 31 to become low-pressure water, and the low-pressure water flows into the cooling flow channel 122 .

[0041] Reference Figure 1 and Figure 5 The non-filler hydraulic end further comprises a connecting shaft 51 and a connecting member 52. One end of the connecting shaft 51 is used for transmission connection with the crankshaft.

[0042] The connecting member 52 is annular and coaxially connected to the outer periphery of the other end of the connecting shaft 51 . The surface of the connecting member 52 is flush with the other end surface of the connecting shaft 51 , and a groove 511 is coaxially provided on the other end surface of the connecting shaft 51 .

[0043] The floating connection structure further comprises an assembly part 6. The assembly shaft comprises a sleeve barrel 61 and an assembly ring 62.

[0044] One end of the sleeve barrel 61 is provided with an opening, and the plunger 2 is embedded in the opening of the sleeve barrel 61 . An interference fit can be adopted between the plunger 2 and the sleeve barrel 61 .

[0045] The assembly ring 62 is coaxially connected to the outer periphery of the sleeve barrel 61. Along the axial direction of the sleeve barrel 61, the assembly ring 62 is located in the middle of the sleeve barrel 61.

[0046] The other end of the sleeve barrel 61 is used to be embedded in the groove 511 of the connecting shaft 51 , and there is a gap between the outer periphery of the sleeve barrel 61 and the groove wall of the groove 511 .

[0047] A gasket 7 is also embedded in the groove 511 . The other end surface of the sleeve barrel 61 is a spherical surface, the center of which coincides with the axis of the sleeve barrel 61 , and the spherical surface is used to abut against the gasket 7 .

[0048] At the same time, when the spherical surface abuts against the gasket 7 and the axis of the sleeve 61 coincides with or is parallel to the axis of the connecting shaft 51 , there is a gap between the assembly part 6 and the connecting part 52 .

[0049] The fillerless hydraulic end further includes a clamp 81 , a retaining spring 82 and an elastic member 9 .

[0050] There are two clamps 81, which are in the shape of a fan ring, and the central angle of the clamp 81 is an obtuse angle or a straight angle. In this embodiment: the central angle of the clamp 81 is a straight angle.

[0051] The surface of the clamp 81 away from the center of its own circle is provided with a coaxial clamping groove 811. The clamping spring 82 is sleeved outside the clamp 81, and the clamping spring 82 is embedded in the clamping groove 811.

[0052] The surface of the clamp 81 facing the center of its own circle is provided with a coaxial embedding groove 812. The connecting member 52, the assembly ring 62, and the elastic member 9 are all embedded in the embedding groove 812.

[0053] In this embodiment: the elastic member 9 includes a disc spring, which is sleeved outside the sleeve barrel 61 and is located on the side of the assembly member 6 away from the connecting member 52; the disc spring is provided with three groups, each group has two disc springs, and the large diameter ends of the two disc springs in any group are opposite to each other.

[0054] The implementation principle of a filler-free hydraulic end in an embodiment of the present application is as follows: the clearance between the plunger 2 and the side wall of the working chamber is matched to reduce the friction and wear between the two; at the same time, when the plunger 2 penetrates into the working chamber to output high-pressure water, a small amount of high-pressure water penetrates between the plunger 2 and the side wall of the working chamber, and a small amount of high-pressure water flows between the plunger 2 and the pressure relief sleeve 3. The small amount of high-pressure water releases the pressure at the pressure relief hole 31 and becomes low-pressure water, thereby avoiding high-pressure leakage and cooling the plunger 2.

[0055] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A packingless hydraulic end, characterized in that: It includes a pump head (1), a pressure relief sleeve (3) and a plunger (2). The pump head (1) is provided with a working chamber. The pressure relief sleeve (3) is connected to the pump head (1), the pressure relief sleeve (3) is in communication with the working chamber, the pressure relief sleeve (3) is provided with a pressure relief hole (31), and the pressure relief hole (31) passes through the pressure relief sleeve (3). One end of the plunger (2) passes through the pressure relief sleeve (3) and is then slidably embedded in the working chamber, with a clearance fit between the plunger (2) and the side wall of the working chamber.

2. The packingless fluid end according to claim 1, characterized in that: The pump head (1) is provided with a cooling flow channel (122). The pressure relief hole (31) is connected to the cooling flow channel (122).

3. The packingless fluid end according to claim 1 or 2, characterized in that: The pressure relief sleeve (3) is provided with a micro-slowing hole (32), the micro-slowing hole (32) passes through the pressure relief sleeve (3), and the micro-slowing hole (32) is located on a side of the pressure relief hole (31) away from the working chamber.

4. The packingless fluid end according to claim 1, characterized in that: There is a clearance fit between the pressure relief sleeve (3) and the plunger (2), and there is a clearance fit between the pressure relief sleeve (3) and the pump head (1).

5. The packingless fluid end according to claim 4, characterized in that: It also comprises a sealing ring (4), wherein the sealing ring (4) fits the plunger (2), the sealing ring (4) fits the pump head (1), and the sealing ring (4) is located on a side of the pressure relief sleeve (3) facing away from the working chamber.

6. The packingless fluid end according to claim 1, characterized in that: A buffer hole (131) is provided on the side wall of the working chamber.

7. The packingless fluid end according to claim 3, characterized in that: The pump body comprises a cylinder body (12) and a bushing (13). The bushing (13) is embedded in the cylinder body (12), and the bushing (13) forms the working chamber. The buffer hole (131) passes through the inner and outer circumferences of the bushing (13).

8. The packingless fluid end according to claim 1, characterized in that: It also includes a connecting shaft (51), a connecting member (52), an assembly member (6), a clamp (81) and an elastic member (9). The connecting member (52) is connected to the outer periphery of the connecting shaft (51). The assembly part (6) is connected to the outer periphery of the other end of the plunger (2). The clamp (81) is provided with an embedding groove (812). The connecting member (52), the assembly member (6), and the elastic member (9) are all embedded in the embedding groove (812).

9. The packingless fluid end according to claim 8, characterized in that: Also includes a retaining ring (82), The clamp (81) is in the shape of a fan ring, the central angle of the clamp (81) is an obtuse angle or a straight angle, the clamp (81) is provided with a clamping groove (811), and the clamp (81) is provided with two The clamping spring (82) is sleeved outside the clamping hoop (81), and the clamping spring (82) is embedded in the clamping groove (811).

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