Piston pump plunger synchronous lubrication device

Abstract

A plunger synchronous lubrication device for a plunger pump. In this invention, the hydraulic end cylinder of the balancing lubrication system is coaxially and fixedly connected to the annular booster cylinder of the booster system. The hydraulic end plunger reciprocates along the hydraulic end cylinder and the annular booster cylinder. The lubricating oil working chamber of the balancing lubrication system and the annular working chamber of the booster system are connected through a connecting pipe. The reciprocating motion of the hydraulic end plunger provides power to the lubricating oil, and the lubricating oil adjusts its lubrication pressure value under the control of the control unit of the oil control system. Its beneficial effects are: a reasonable structural design, improved lubrication conditions of the hydraulic end plunger of the plunger pump, achieving essentially uniform pressure pulsation on both sides of the sealing ring, effectively extending the service life of the sealing ring; pressurized delivery of lubricating oil within a closed pipeline, preventing contamination of the lubricating oil by external foreign matter, ensuring lubricating oil return to the lubricating oil tank; extended service life of the hydraulic end plunger assembly, reduced maintenance frequency, and improved plunger pump efficiency.

Description

Technical Field

[0001] This invention relates to a plunger pump, and more particularly to a plunger pump plunger synchronous lubrication device, belonging to the field of oil and gas development technology. Background Technology

[0002] In oil and gas development, large-displacement high-pressure plunger pumps are mainly used for booster injection operations, which involve large injection volumes, high pressures, and long operating cycles. When the plunger reciprocates under high pressure and high frequency, related components are prone to wear and heat generation, requiring forced lubrication to reduce wear and allow the generated heat to be dissipated and carried away through the lubrication chamber by the lubricating oil.

[0003] Existing plunger pumps typically use a hydraulic pump to pressurize the lubricating oil in their hydraulic end forced lubrication system, with a pressure relief valve limiting the oil supply pressure. The lubrication chamber and hydraulic end are sealed with packing, while the lubrication chamber and connecting rod end are sealed with soft packing. Lubricating oil leaks from the gaps in the soft packing at the connecting rod end, flows into the oil collection sump, and returns to the lubricating oil tank. The pressure on the hydraulic end seal comes from the liquid pumped by the hydraulic end. Due to the characteristics of plunger pumps, the pressure of the pumped liquid fluctuates with the reciprocating motion of the plunger. During plunger pump operation, the packing seal is subjected to high-frequency pulsating pressure on one side, resulting in harsh working conditions, susceptibility to failure, and increased maintenance workload. The soft packing seal relies on the axial clamping force generated by the gland to deform and press tightly against the plunger surface. Excessive clamping force leads to high resistance on the plunger, rapid heating of the soft packing, and a short lifespan; insufficient clamping force results in poor sealing and large leakage. Wear of the soft packing produces particulate matter, which mixes into the lubricating oil and contaminates it. The oil collection sump is covered by a cover to prevent foreign objects from entering. However, there is a gap between the lubricating oil pump pipeline and the cover, so the oil collection sump cannot be completely sealed. During use, due to the intrusion of moisture, water, ash and other media, the lubricating oil needs to be changed frequently. When the temperature is too low, the viscosity of the lubricating oil is high, and the lubricating oil in the oil collection sump cannot flow back to the lubricating oil tank in time, causing lubrication system failure. Summary of the Invention

[0004] In order to overcome the above-mentioned shortcomings of the hydraulic end plunger forced lubrication of existing plunger pumps, the present invention provides a plunger synchronous lubrication device for plunger pumps.

[0005] The technical solution adopted by the present invention to solve its technical problem is: a plunger pump plunger synchronous lubrication device, including a hydraulic end cylinder and a hydraulic end plunger. The synchronous lubrication device includes a balance lubrication system, a booster system, and an oil control system. The hydraulic end cylinder of the balance lubrication system is coaxially and fixedly connected to the annular booster cylinder of the booster system. The hydraulic end plunger reciprocates along the hydraulic end cylinder and the annular booster cylinder.

[0006] The lubricating oil working chamber of the balanced lubrication system is connected to the annular working chamber of the booster system via a connecting pipe.

[0007] The reciprocating motion of the hydraulic plunger provides power to the lubricating oil, and the lubricating oil adjusts its lubrication pressure value under the control of the control unit of the oil control system.

[0008] The hydraulic plunger reciprocates along the hydraulic cylinder and the annular booster cylinder, changing the size of the annular working chamber and providing power to the lubricating oil.

[0009] The inner bore of the hydraulic cylinder is provided with sealing component I and sealing component II in sequence along the axial direction of the hydraulic plunger, with sealing component I and sealing component II installed facing each other.

[0010] The hydraulic cylinder between sealing component I and sealing component II is provided with two radial through holes I, one of which is connected to the outlet pipe and the other is connected to the connecting pipe.

[0011] The radial clearance between the hydraulic plunger and the hydraulic cylinder, and the radial hole I, constitute the lubricating oil working chamber.

[0012] The Glyd ring I, guide ring I, and dustproof gasket I of the sealing assembly I are installed sequentially from the inside to the outside of the lubricating oil working chamber.

[0013] The sealing assembly II, consisting of the step seal, guide ring II, and dustproof gasket II, is installed sequentially from the inside of the lubricating oil working chamber outwards.

[0014] One end of the annular booster cylinder is fixedly connected to the hydraulic cylinder, and the other end is provided with an annular working chamber. Two radial holes II of the annular booster cylinder are connected to the annular working chamber. One radial hole II is connected to the connecting pipe, and the other radial hole II is connected to the inlet pipe.

[0015] The annular working chamber is provided with an annular booster plunger that is fixedly connected to the hydraulic end plunger. The outer ring sealing assembly and the inner ring sealing assembly provided in the annular working chamber radially seal the annular working chamber and the annular booster plunger.

[0016] The outer ring sealing assembly has a Glyd ring III and a guide ring III arranged sequentially from the inside to the outside along the annular working cavity; the inner ring sealing assembly has a Glyd ring IV and a guide ring IV arranged sequentially from the inside to the outside along the annular working cavity.

[0017] The outer end of the annular booster plunger is fixedly connected to two semi-circular blocks, which together form a circle and are fixedly connected to the hydraulic end plunger.

[0018] The pressure sensor for measuring the pressure of the hydraulic end working chamber of the oil control system is connected to the control unit; two or more pressure stage units of the oil control system are connected in parallel, and the electrically controlled directional valve of each pressure stage unit is connected to the control unit respectively. The control unit selects pressure stage units with different pressure values.

[0019] When the hydraulic plunger reciprocates to provide power to the lubricating oil, the lubricating oil of the oil control system passes through the inlet pipe, the annular working chamber, the connecting pipe, the lubricating oil working chamber, the outlet pipe, and the pressure stage unit in sequence and returns to the oil tank.

[0020] The pressure stage unit includes a pressure relief valve and an electrically controlled directional valve connected in series; a pressure relief pipeline with a pressure relief valve is provided between the outlet pipe and the oil tank.

[0021] The beneficial effects of this invention are: reasonable structural design, improved lubrication conditions of the hydraulic end plunger of the plunger pump, basically consistent pressure pulsation on both sides of the sealing ring, effectively extending the service life of the sealing ring; pressurized delivery of lubricating oil in a closed pipeline, preventing external foreign matter from contaminating the lubricating oil, ensuring the lubricating oil returns to the lubricating oil tank; extended service life of the hydraulic end plunger assembly, reduced maintenance frequency, and improved working efficiency of the plunger pump. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the plunger pump plunger synchronous lubrication device of the present invention.

[0023] Figure 2 This is a schematic diagram of the balanced lubrication system and the booster system of the present invention.

[0024] In the diagram: 1. Hydraulic end cylinder, 2. Dustproof gasket I, 3. Guide ring I, 4. Glyd ring I, 5. Step seal, 6. Guide ring II, 7. Dustproof gasket II, 8. Annular booster cylinder, 9. Glyd ring III, 10. Guide ring III, 11. Bolt, 12. Semi-circular retaining block, 13. Hydraulic end plunger, 14. Inner ring sealing assembly, 15. Outer ring sealing assembly, 16. Annular booster plunger, 17. Guide ring IV, 18. Glyd ring IV, 19. Annular working chamber, 20. Inlet check valve, 21. Filter, 22. Oil tank, 23. Limit 24. Pressure relief valve I, 25. Control unit, 26. Electrically controlled directional valve II, 27. Electrically controlled directional valve I, 28. Liquid outlet check valve, 29. Pressure relief valve, 30. Pressure sensor, 31. Lubricating oil working chamber, 32. Hydraulic end working chamber, 33. Connecting pipe, 34. Radial through hole I, 35. Pressure stage unit, 36. Sealing assembly I, 37. Sealing assembly II, 38. Radial hole II, 39. Liquid outlet pipe, 40. Liquid inlet pipe, 100. Balanced lubrication system, 200. Pressure boosting system, 300. Oil control system. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings and embodiments. However, those skilled in the art should understand that the present invention is not limited to the specific embodiments listed, and any embodiment that conforms to the spirit of the present invention should be included within the scope of protection of the present invention.

[0026] In the description of this invention, it should be noted that the terms "vertical", "up", "down", "left", "right", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing or simplifying the description of this invention, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0027] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," "join," and "seal" should be interpreted broadly. For example, a connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; it can also refer to the internal communication between two components. A seal can be an oil seal, a packing seal, or other sealing methods. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] See appendix Figure 1 , 2 The present invention provides a plunger synchronous lubrication device for a plunger pump, comprising a balanced lubrication system 100, a booster system 200, and an oil control system 300. The hydraulic end cylinder 1 of the balanced lubrication system 100 is coaxially and fixedly connected to the annular booster cylinder 8 of the booster system 200. The hydraulic end plunger 13 reciprocates along the hydraulic end cylinder 1 and the annular booster cylinder 8.

[0029] The lubricating oil working chamber 31 of the balanced lubrication system 100 is connected to the annular working chamber 19 of the booster system 200 through a connecting pipe 33.

[0030] The reciprocating motion of the hydraulic plunger 13 provides power to the lubricating oil, and the lubricating oil adjusts its lubrication pressure value under the control of the control unit 25 of the oil control system 300.

[0031] The hydraulic plunger 13 reciprocates along the hydraulic cylinder 1 and the annular booster cylinder 8, changing the volume of the annular working chamber 19 and providing power to the lubricating oil.

[0032] The balanced lubrication system 100 includes a hydraulic cylinder 1, a lubricating oil working chamber 31, a sealing component I 36, and a sealing component II 37. The sealing component I 36 and the sealing component II 37 are sequentially arranged along the axial direction of the hydraulic plunger 13 in the inner hole of the hydraulic cylinder 1, and the sealing component I 36 and the sealing component II 37 are installed facing each other.

[0033] Furthermore, the sealing assembly I36 includes a Glyd ring I4, a guide ring I3, and a dustproof gasket I2, which are installed sequentially from the inside to the outside of the lubricating oil working chamber 31; preferably, the guide ring I3 and the dustproof gasket I2 are made of polytetrafluoroethylene.

[0034] Furthermore, the sealing assembly II37 includes a step seal 5, a guide ring II6, and a dustproof gasket II7, which are installed sequentially from the inside to the outside of the lubricating oil working chamber 31; preferably, the guide ring II6 and the dustproof gasket II7 are made of polytetrafluoroethylene.

[0035] The hydraulic end cylinder 1 between the sealing component I 36 and the sealing component II 37 is provided with two radial through holes I 34, one of which is connected to the outlet pipe 39, and the other is connected to the connecting pipe 33.

[0036] The radial clearance between the hydraulic plunger 13 and the hydraulic cylinder 1, and the radial hole I 34, constitute the lubricating oil working chamber 31.

[0037] The pressurization system 200 includes an annular pressurization cylinder 8, an annular pressurization plunger 16, an outer ring sealing assembly 15, and an inner ring sealing assembly 14. One end of the annular pressurization cylinder 8 is fixedly connected to the hydraulic end cylinder 1 of the balance lubrication system 100, and the other end is provided with an annular working chamber 19, which is an annular deep groove. Two radial holes II 38 of the annular pressurization cylinder 8 are connected to the annular working chamber 19. One of the radial holes II 38 is connected to the connecting pipe 33, and the other radial hole II 38 is connected to the liquid inlet pipe 40.

[0038] The piston portion at one end of the annular booster plunger 16 is located inside the annular working chamber 19, and the other end is fixedly connected to the hydraulic end plunger 13; the outer ring sealing assembly 15 and the inner ring sealing assembly 14 provided in the annular working chamber 19 radially seal the annular working chamber 19 and the annular booster plunger 16.

[0039] Furthermore, the outer ring sealing assembly 15 has its Glyd ring III 9 and guide ring III 10 arranged sequentially from the inside to the outside along the annular working cavity 19; the inner ring sealing assembly 14 has its Glyd ring IV 18 and guide ring IV 17 arranged sequentially from the inside to the outside along the annular working cavity 19.

[0040] The outer end of the annular booster plunger 16 is fixedly connected to two semi-circular locking blocks 12, which together form a circle. The two semi-circular locking blocks 12 are fixedly connected to the annular booster plunger 16 by bolts 11. The two semi-circular locking blocks 12 are also fixedly connected to the hydraulic end plunger 13. When the hydraulic end plunger 13 reciprocates, it drives the annular booster plunger 16 to reciprocate synchronously. The reciprocating motion of the annular booster plunger 16 causes the volume of the annular working chamber 19 to change pulsatingly, providing power to the lubricating oil. This balances the pressure pulsation on both sides of the plunger seal ring of the lubrication system 100, effectively extending the service life of the seal ring.

[0041] The oil control system 300 includes a control unit 25, an oil tank 22, two or more pressure stage units 35, and a pressure sensor 30 for measuring the pressure of the hydraulic end working chamber 32. Each pressure stage unit 35 consists of a pressure limiting valve and an electrically controlled directional valve connected in series. Two or more pressure stage units 35 are connected in parallel, and each pressure stage unit 35 is preset with a fixed pressure value. The pressure sensor 30 and the electrically controlled directional valve of each pressure stage unit 35 are respectively connected to the control unit 25. During operation, the control unit 25 selects pressure stage units 35 with different pressure values ​​according to process requirements. A pressure relief pipeline with a pressure relief valve 29 is provided between the outlet pipe 39 and the oil tank 22.

[0042] Figure 1 The diagram illustrates two of the multiple pressure stage units 35: pressure relief valve I 23 and electrically controlled directional valve I 27, and pressure relief valve II 24 and electrically controlled directional valve II 26. The electrically controlled directional valves I 27 and II 26 are pre-set with different pressure values, and the lubrication pressure is selected by the control unit 25 according to the design requirements of the plunger pump injection process.

[0043] When the hydraulic plunger 13 reciprocates, it provides power to the lubricating oil. After being filtered by the filter 21 from the oil tank 22, the lubricating oil passes through the inlet check valve 20, the inlet pipe 40, the annular working chamber 19, the connecting pipe 33, the lubricating oil working chamber 31, the outlet pipe 39, the outlet check valve 28, and the pressure stage unit 35 before returning to the oil tank 22. The lubricating oil circulates repeatedly to complete the sealing and lubrication of the hydraulic plunger 13.

[0044] Furthermore, when the annular booster plunger 16 reciprocates along with the hydraulic end plunger 13, increasing the volume of the annular working chamber 19, lubricating oil from the lubricating oil tank 22 is drawn into the filter 21, passes through the inlet check valve 20 and the inlet pipe 40, and enters the annular working chamber 19. The inlet check valve 20 ensures that the lubricating oil flows unidirectionally into the annular working chamber 19. When the volume of the annular working chamber 19 is compressed, the inlet check valve 20 ensures that the lubricating oil does not flow back into the oil tank 22. The lubricating oil is forced into the lubricating oil working chamber 31 through the connecting pipe 33. Excess oil flows into the pressure stage unit 35 through the outlet pipe 39 and the outlet check valve 28. The outlet check valve 28 ensures that the lubricating oil does not flow back into the lubricating oil working chamber 31. When the pressure in the pipeline exceeds the set maximum safe pressure value, the pressure relief valve 29 on the pressure relief pipeline opens to ensure the safe operation of the synchronous lubrication device. Pressure sensor 30 monitors the pressure in the hydraulic end working chamber 32 and feeds it back to control unit 25 in real time. Control unit 25 controls the electronically controlled directional valve II 26 and electronically controlled directional valve I 27, and connects the corresponding pressure stage unit 35 according to the pressure value in the hydraulic end working chamber 32 to adjust the lubrication pressure.

[0045] The present invention discloses a plunger synchronous lubrication device for a plunger pump, which relies on the movement of the hydraulic end plunger 13 to provide power for the lubricating oil. The working chamber of the lubricating oil and the two sides of the hydraulic end sealing ring pulsate in unison. Under the control of the control unit, the pressure of the lubricating oil is adjusted to reduce the pressure difference between the working chamber of the lubricating oil and the two sides of the sealing ring at the hydraulic end, thereby improving the stress condition of the sealing ring and increasing its service life.

[0046] The lubricating oil is transported in a closed pipeline, effectively isolating it from the external environment, reducing contamination of the lubricating oil, and effectively extending its service life. The lubricating oil is then pressurized and transported back to the hydraulic oil tank in a closed system, ensuring the stable operation of the lubrication system.

[0047] It should be noted that the above embodiments are examples and not limitations of the present invention, and those skilled in the art will be able to design many alternative embodiments without departing from the scope of the claims of this patent.

Claims

1. A plunger synchronous lubrication device for a plunger pump, comprising a hydraulic end cylinder and a hydraulic end plunger, characterized in that: The synchronous lubrication device includes a balanced lubrication system, a pressurization system, and an oil control system. The hydraulic cylinder at the hydraulic end of the balanced lubrication system is coaxially and fixedly connected to the annular pressurization cylinder of the pressurization system. The hydraulic plunger reciprocates along the hydraulic cylinder at the hydraulic end and the annular pressurization cylinder. One end of the annular booster cylinder is fixedly connected to the hydraulic end cylinder, and the other end is provided with an annular working chamber. An annular pressure boosting plunger is fixedly connected to the hydraulic end plunger inside the annular working chamber. The lubricating oil working chamber of the balanced lubrication system is connected to the annular working chamber of the booster system via a connecting pipe. The reciprocating motion of the hydraulic plunger provides power to the lubricating oil, and the lubricating oil adjusts its lubrication pressure value under the control of the control unit of the oil control system. The hydraulic plunger reciprocates along the hydraulic cylinder and the annular booster cylinder, changing the size of the annular working chamber and providing power to the lubricating oil.

2. The plunger synchronous lubrication device for a plunger pump according to claim 1, characterized in that: The inner bore of the hydraulic cylinder is provided with sealing component I and sealing component II in sequence along the axial direction of the hydraulic plunger, with sealing component I and sealing component II installed facing each other; The hydraulic cylinder between sealing component I and sealing component II is provided with two radial through holes I, one of which is connected to the outlet pipe and the other is connected to the connecting pipe. The radial clearance between the hydraulic plunger and the hydraulic cylinder, and the radial hole I, constitute the lubricating oil working chamber.

3. The plunger synchronous lubrication device for a plunger pump according to claim 2, characterized in that: The Glyd ring I, guide ring I, and dustproof gasket I of the sealing assembly I are installed sequentially from the inside of the lubricating oil working chamber to the outside. The sealing assembly II, consisting of the step seal, guide ring II, and dustproof gasket II, is installed sequentially from the inside of the lubricating oil working chamber outwards.

4. The plunger synchronous lubrication device for a plunger pump according to claim 1, characterized in that: The two radial holes II of the annular booster cylinder are connected to the annular working chamber. One radial hole II is connected to the connecting pipe, and the other radial hole II is connected to the liquid inlet pipe. The outer ring sealing assembly and inner ring sealing assembly of the annular working chamber provide radial sealing between the annular working chamber and the annular booster plunger.

5. The plunger synchronous lubrication device for a plunger pump according to claim 4, characterized in that: The outer ring sealing assembly has a Glyd ring III and a guide ring III arranged sequentially from the inside to the outside along the annular working cavity; the inner ring sealing assembly has a Glyd ring IV and a guide ring IV arranged sequentially from the inside to the outside along the annular working cavity.

6. The plunger synchronous lubrication device for a plunger pump according to claim 5, characterized in that: The outer end of the annular booster plunger is fixedly connected to two semi-circular blocks, which together form a circle and are fixedly connected to the hydraulic end plunger.

7. The plunger synchronous lubrication device for a plunger pump according to claim 1, characterized in that: The pressure sensor for measuring the pressure of the hydraulic end working chamber of the oil control system is connected to the control unit; two or more pressure stage units of the oil control system are connected in parallel, and the electrically controlled directional valve of each pressure stage unit is connected to the control unit respectively. The control unit selects pressure stage units with different pressure values.

8. The plunger synchronous lubrication device for a plunger pump according to claim 7, characterized in that: When the hydraulic plunger reciprocates to provide power to the lubricating oil, the lubricating oil of the oil control system passes through the inlet pipe, the annular working chamber, the connecting pipe, the lubricating oil working chamber, the outlet pipe, and the pressure stage unit in sequence and returns to the oil tank.

9. The plunger synchronous lubrication device for a plunger pump according to claim 8, characterized in that: The pressure stage unit includes a pressure relief valve and an electrically controlled directional valve connected in series; a pressure relief pipeline with a pressure relief valve is provided between the outlet pipe and the oil tank.

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