WO2021081752A1 - Five-cylinder plunger pump having integrated-type power end structure - Google Patents

Abstract

A five-cylinder plunger pump having an integrated-type power end structure, said pump comprising a power end assembly (1), a fluid end assembly (3) and a reduction gearbox assembly (2). A first end of the power end assembly (1) is connected to the fluid end assembly (3), and the other end of the power end assembly (1) is connected to the reduction gearbox assembly (2). The power end assembly (1) comprises a crankcase body, a crosshead body and a spacer frame (14). The crankcase body and the crosshead body are integrally welded to form a power end housing (5). The power end housing (5) is connected to the spacer frame (14) and comprises vertical plates (24), bearing seats (25), a front cover (28), a rear cover (23), a base plate (26), support plates (27), and an upper cover (29). There are six vertical plates (24) and six bearing seats (25), each vertical plate (24) connects to one corresponding bearing seat (25), and the six vertical plates (24) are arranged parallel to one another to form a power end cavity. The base plate (26) is installed in the lower part of the power end cavity, the upper cover (29) is installed in the upper part of the power end cavity, the front cover (28) is installed at the front end of the power end cavity, the rear cover (23) is installed at the rear end of the power end cavity, and the support plates (27) are disposed between two adjacent vertical plates (24) that are arranged parallel to one another.

Description

Five-cylinder plunger pump with integral power end structure Technical field

The invention relates to the technical field of plunger pumps, in particular to a five-cylinder plunger pump with an integral power end structure.

Background technique

With the further development of unconventional oil and gas and shale oil and gas, the pressure and displacement requirements of fracturing operations are constantly increasing. Not only does the operating pressure continue to increase with the increase in the depth of horizontal wells, but also the discharge required for single-stage wells The volume is also getting higher and higher, which makes the scale of fracturing construction larger and larger, and the harsh operating conditions also place higher requirements on the fracturing equipment, especially the plunger pump. At present, in the process of shale oil and gas development, the operating pressure generally reaches 80-90MPa or even higher, and the single-stage operating displacement is generally 1800m ³ -2000m ³ or more. The plunger pump must not only be able to meet the high pressure and large displacement Continuous operation must also ensure the quality stability under continuous high-load operation and reduce pump shutdown time and maintenance time. At present, the most widely used fracturing truck on the market is the 2500 fracturing truck, which is equipped with a 2800hp plunger pump. Other commonly used fracturing pumps include 2500hp pump, 3300hp pump, 4000hp pump, etc. Take 2800hp pump as an example, due to power limitation In high-pressure operation, the single pump displacement is relatively low. A ^{shale gas well site with a single-stage displacement requirement of 14-16m 3} /min requires close to 20 fracturing trucks to operate at the same time to meet the total fracturing operation. Displacement requirements will occupy a large area of the well site and increase the difficulty of equipment layout in small oil and gas field well sites. In addition, conventional plunger pumps are facing increasingly harsh operating conditions and remain high for a long time. Load work, the frequency of problems is also increasing, increasing the cost of maintenance and overhaul. In recent years, electric drive fracturing operations have emerged. The use of electric motor drive has also solved the problem of limited diesel engine power, and is more suitable for driving high-power plunger pumps.

With the increase of the power of the plunger pump, higher requirements are put forward for the operation stability of the plunger pump itself, especially the strength of the power end structure of the plunger pump, and the support stability.

Summary of the invention

The purpose of the present invention overcomes the shortcomings of the prior art and provides a five-cylinder plunger pump with an integral power end structure, which adopts an integral welding structure for the crankcase and the crosshead box in the power end assembly of the five-cylinder plunger pump , Which makes the structural strength of the power end assembly higher, and the support stability is better, which can reduce the vibration of the whole pump. The cylinder spacing is 13-14 inches, which provides protection for the high-power output of the five-cylinder plunger pump. The power of the specific five-cylinder plunger pump can reach 7000hp. The high-power five-cylinder plunger pump can effectively solve the shale gas cracking well. The narrow field area and the need for more fracturing equipment can reduce the use of equipment and facilitate the layout of the well site. The 11-inch long-stroke design can better realize the large-displacement work requirements and improve work efficiency. The multi-point support design for the crankcase, crosshead box and hydraulic end assembly can improve the support strength of the five-cylinder plunger pump, reduce vibration, and better ensure high-load operation and more stable operation. The five-cylinder plunger pump adopts the two-stage deceleration of planetary gearbox and parallel-stage gearbox to obtain a large reduction ratio. Increasing the reduction ratio can reduce the input torque, increase the service life of the gearbox, and better match the engine and Motor selection; increasing the reduction ratio can also effectively reduce the stroke times of the five-cylinder plunger pump and prolong the service life of each component.

The present invention is achieved through the following technical solutions: a five-cylinder plunger pump with an integral power end structure, including a power end assembly, a hydraulic end assembly and a reduction box assembly, one end of the power end assembly is connected to The hydraulic end assembly is connected, and the other end of the power end assembly is connected to the reduction box assembly. The power end assembly includes a crankcase, a crosshead case and a spacer, the crankcase and the crosshead case The body is integrally welded to form a power end shell, which is connected to the spacer frame. The power end shell includes a vertical plate, a bearing seat, a front end plate, a rear cover plate, a bottom plate, a support plate and an upper cover plate. The number of vertical plates is 6, the number of bearing seats is 6, one vertical plate is connected to one bearing seat, and the 6 vertical plates are arranged in parallel to form a power end cavity, and the bottom plate is installed at the bottom of the power end cavity, An upper cover plate is installed on the top of the power end cavity, a front end plate is installed at the front end of the power end cavity, and a rear cover plate is installed at the rear end of the power end cavity. A supporting board is arranged between the vertical boards.

Further, a crankshaft support body is provided at the bottom of the crankcase body, and the crankshaft support body is used to support the crankshaft case body.

Further, a crosshead support body is provided at the bottom of the crosshead box body, and the crosshead support body is used to support the crosshead box body.

Further, a hydraulic support body is provided at the bottom of the spacer, and the hydraulic support body is used to support the hydraulic end assembly.

Further, a crankshaft is provided in the crankcase body, the crankshaft is forged integrally with alloy steel, the crankshaft includes six journals and five cranks, and a crankshaft is provided between two adjacent journals. In other words, the cylinder spacing of the five-cylinder plunger pump is 13-14 inches.

Further, a spline is provided in the crankshaft, and the reduction box assembly is connected with the crankshaft spline.

Further, a crosshead assembly is arranged in the crosshead box, a connecting rod assembly is arranged between the crankcase and the crosshead box, a crankshaft is arranged in the crankcase, and one end of the connecting rod assembly passes through the connecting rod. The bearing bush is connected with the crankshaft, and the other end of the connecting rod assembly is connected with the crosshead assembly through a crosshead bushing. The connecting rod bushing and the crosshead bushing are both steel-backed bushings with alloy plating.

Further, the stroke of the five-cylinder plunger pump of the integral power end structure is 11 inches.

Further, the reduction gearbox assembly includes a planetary-stage reduction gearbox and a parallel-stage reduction gearbox. One end of the planetary-stage reduction gearbox is connected to the power end assembly, and the other end of the planetary-stage reduction gearbox is connected to the parallel-stage reduction gearbox. The two-stage deceleration of the gearbox assembly is realized through the planetary gearbox and the parallel-stage gearbox, and the reduction ratio is 8:1-15:1.

Compared with the prior art, the present invention has the following beneficial effects: 1. The integral welding structure is adopted for the crankcase and the crosshead box in the power end assembly of the five-cylinder plunger pump, so that the structural strength of the power end assembly is stronger. High, better support stability, can reduce the vibration of the whole pump. 2. The cylinder spacing is 13-14 inches, which increases the bearing area of the connecting rod, crosshead and bearing bush, and provides protection for the high-power output of the five-cylinder plunger pump. The power of the specific five-cylinder plunger pump can reach 7000hp. The high-power five-cylinder plunger pump can effectively solve the problems of narrow shale gas fracturing wellsite area and more fracturing equipment required, reducing the use of equipment and facilitating well site layout. 3. The 11-inch long-stroke design can better realize the large displacement operation requirements and improve the operation efficiency. 4. The multi-point support design for the crankcase, crosshead box and hydraulic end assembly can improve the support strength of the five-cylinder plunger pump, reduce vibration, better ensure high-load operation, and run more smoothly. 5. The five-cylinder plunger pump adopts the two-stage deceleration of planetary gearbox and parallel-stage gearbox, which is beneficial to obtain a large reduction ratio. Increasing the reduction ratio can reduce the input torque, increase the service life of the gearbox, and better match. Engine and motor selection; increasing the reduction ratio can also effectively reduce the stroke times of the five-cylinder plunger pump and prolong the service life of each component.

The present invention will be described in detail below with reference to the drawings and specific embodiments.

Description of the drawings

Figure 1 is a schematic diagram of the structure of a five-cylinder plunger pump.

Figure 2 is a schematic diagram of the structure of the power end assembly.

Figure 3 is a schematic diagram of the structure of the power end housing.

Figure 4 is a schematic diagram of the structure of the reduction gearbox assembly.

Figure 5 is a cross-sectional view of the planetary gearbox.

Figure 6 is a cross-sectional view of a parallel-stage reduction gearbox.

Figure 7 is a schematic diagram of the crankshaft structure.

Figure 8 is a schematic diagram of the connecting rod assembly and the crosshead assembly connection structure.

Among them, 1. Power end assembly, 2. Gearbox assembly, 3. Hydraulic end assembly, 4. Drive flange, 5. Power end housing, 6. Crankshaft, 7. Bearing, 8. Connecting rod bearing , 9. Connecting rod body, 10. Slide rail, 11. Cross head, 12. Cross head bearing, 13. Tie rod, 14. Spacer, 15. Long screw, 16. Nut, 17. Clamp, 18. Plunger , 19. Valve box, 20. Crankshaft support, 21. Crosshead support, 22. Hydraulic support, 23. Rear cover, 24. Vertical plate, 25. Bearing seat, 26. Bottom plate, 27. Support plate , 28. Front end plate, 29. Upper cover, 30. Parallel-stage gearbox, 31. Planetary gearbox, 32. Ring gear, 33. Planetary gear, 34. Sun gear, 35. Planetary carrier, 36. Big gear, 37. Small gear, 38. Spline, 39. Connecting rod cover, 40. Connecting rod bolt, 41. Cross head gland, 42. Guide plate, 43. Screw.

Detailed ways

An embodiment, as shown in Figures 1 to 8, a five-cylinder plunger pump with an integral power end structure includes a power end assembly 1, a hydraulic end assembly 3, and a reduction box assembly 2. The power end assembly One end of the assembly 1 is connected to the hydraulic end assembly 3, and the other end of the power end assembly 1 is connected to the reduction box assembly 2. The power end assembly 1 includes a crankcase, a crosshead box and a spacer 14 The crankcase body and the crosshead box body are integrally welded to form a power end shell 5. The power end shell 5 is connected to the spacer frame 14. The power end shell 5 includes a vertical plate 24, a bearing seat 25, and a front end plate. 28. The back cover 23, the bottom plate 26, the support plate 27 and the upper cover 29, the number of the vertical plates 24 is 6, the number of the bearing seats 25 is 6, and one vertical plate 24 is correspondingly connected to a bearing seat 25, Six vertical plates 24 are arranged in parallel to form a power end cavity. A bottom plate 26 is installed at the bottom of the power end cavity, and an upper cover 29 is installed on the top of the power end cavity. A front end plate 28 is installed at the front end, a rear cover 23 is installed at the rear end of the power end cavity, and a support plate 27 is provided between two adjacent vertical plates 24 arranged in parallel. The crankcase and crosshead box in the power end assembly 1 of the five-cylinder plunger pump adopt an integral welding structure, which makes the structure of the power end assembly 1 stronger, better support stability, and can effectively reduce the power end shell. The body 5 bears deformation, which can reduce the vibration of the whole pump and improve the operation stability of the five-cylinder plunger pump.

A crankshaft support body 20 is provided at the bottom of the crankcase body, and the crankshaft support body 20 is used to support the crankshaft case body. A crosshead support body 21 is provided at the bottom of the crosshead box body, and the crosshead support body 21 is used to support the crosshead box body. The bottom of the spacer 14 is provided with a hydraulic support 22, and the hydraulic support 22 is used to support the hydraulic end assembly 3. The five-cylinder plunger pump adopts a multi-point support design, which can improve the support strength of the five-cylinder plunger pump, reduce vibration, and better ensure high-load operation and run more smoothly.

A crankshaft 6 and a bearing 7 are provided in the crankcase body. The crankshaft 6 is integrally forged with alloy steel. The crankshaft 6 includes six journals and five crankshafts, between two adjacent journals. A crank is set, and the cylinder spacing of the five-cylinder plunger pump is 13-14 inches. Increasing the cylinder spacing design is beneficial to increase the contact area between the crankshaft 6 and the connecting rod bush 8, the crosshead 11 and the slide rail 10, and improve the support strength. Provide guarantee for the high-power output of the five-cylinder plunger pump. The high-power five-cylinder plunger pump can effectively solve the problems of narrow shale gas fracturing wellsite area and more fracturing equipment required, which can reduce the use of equipment and facilitate Well site layout. There are 6 bearings 7 and the 6 bearings 7 are installed on the six journals. At the same time, the outer ring of the bearing 7 is assembled on the 6 bearing seats 25 of the power end housing 5, and the rotary motion can be realized in the bearing seat 25.

The crankshaft 6 is provided with a spline 38, the reduction box assembly 2 is connected to the power end housing 5 by bolts, and the reduction box assembly 2 is provided with an external spline, and the external spline is connected to the spline 38 Connected for power output, the installation angle of the reduction box assembly 2 can be adjusted according to the input requirements. The reduction box assembly 2 is provided with a driving flange 4, and the driving flange 4 is connected with an external power source to realize power input.

A crosshead assembly is arranged in the crosshead box body, a connecting rod assembly is arranged between the crankcase body and the crosshead box body, a crankshaft 6 is arranged in the crankshaft box body, and one end of the connecting rod assembly passes through the connecting rod bearing bush 8 Connected to the crankshaft 6, the other end of the connecting rod assembly is connected to the crosshead assembly through the crosshead bearing 12 to realize reciprocating swing, and the other end of the crosshead assembly is connected to the pull rod 13. The tie rod 13 has a hollow structure. The connecting rod bearing 8 and the crosshead bearing 12 are both steel-backed bearings with alloy plating. The width to diameter ratio is large, and the support strength is high.

Slide rails 10 are fixed on the support plate 27 in the power end housing 5, there are two slide rails 10, and the two slide rails 10 form a semicircular space. The crosshead 11 is installed in the semicircular space to achieve reciprocation. Straight line movement.

The crosshead always has a split structure design, including the crosshead gland 41 and the crosshead 11. The crosshead gland 41 and the crosshead 11 are connected to facilitate the assembly and disassembly of the connecting rod assembly.

The connecting rod assembly includes a connecting rod cover 39 and a connecting rod body 9. The connecting rod cover 39 and the connecting rod body 9 are made of integral forging and then cut with high strength. The connecting rod cover 39 and the connecting rod body 9 are connected by bolts. Specifically, one end of the connecting rod body 9 is connected to the crank through the connecting rod cover 39, the connecting rod bolt 40 and the connecting rod bearing bush 8, and the other end of the connecting rod body 9 is connected to the crosshead through the crosshead gland 41 and the crosshead bearing bush 12 11Connect. The upper and lower ends of the crosshead 11 are respectively fixed with guide plates 42 by screws 43. The guide plates 42 are made of copper alloy and directly contact the slide rail 10 for relative movement.

The crankshaft 6, the connecting rod body 9, and the crosshead 11 are all designed with a lubricating oil circuit for lubricating the bearing 7, the connecting rod bushing 8, and the crosshead bushing 12.

The hydraulic end assembly 3 includes a valve box 19, a plunger 18, a clamp 17, etc. The hydraulic end assembly 3 connects the plunger 18 and the tie rod 13 together through the clamp 17, and uses a long screw 15 and a nut 16 to connect the plunger 18 and the tie rod 13 together. It is fixed on the spacer frame 14, and the long screw 15 is connected to the power end housing 5 through threads.

The stroke of the five-cylinder plunger pump with the integral power end structure is 11 inches. The long-stroke design is very suitable for the current shale gas fracturing zipper operation requirements, reducing the number of wellsite equipment and improving operation efficiency and economy.

The reduction gearbox assembly 2 includes a planetary-stage reduction gearbox 31 and a parallel-stage reduction gearbox 30. One end of the planetary-stage reduction gearbox 31 is connected to the power end assembly 1, and the other end of the planetary-stage reduction gearbox 31 is connected to the parallel-stage reduction gearbox. The gearbox 30 is connected, and the two-stage deceleration of the gearbox assembly 2 is realized through the planetary gearbox 31 and the parallel-stage gearbox 30, and the reduction ratio is 8:1-15:1. The parallel-stage reduction gearbox 30 includes a large gear 36 and a small gear 37 to perform one-stage reduction; the planetary-stage reduction gearbox 31 is composed of an inner ring gear 32, four planet gears 33, a sun gear 34, and a planet carrier 35 to form a planetary gear mechanism. Two-stage deceleration. The sun gear 34 is located at the center of the planetary gear mechanism, meshes with the planet gear 33 and is coaxial with the large gear 36 of the parallel-stage reduction box 30. During operation, the driving flange 4 is connected with an external power source to drive the input shaft to rotate, and is transmitted to the large gear 36 through the pinion 37 to achieve a one-stage reduction, and is transmitted to the sun gear 34 through the large gear 36, and the sun gear 34 drives the planet carrier 35 through the planet gear 33 The two-stage deceleration is realized, and the power is finally transmitted to the crankshaft 6 through the spline 38. A large transmission ratio can be obtained through the two-stage speed change, which effectively reduces the input torque and reduces the stroke frequency of the pump.

Working principle: The external power or speed drives the gearbox assembly 2 to rotate through the drive flange 4, and the power and torque are transmitted to the crankshaft 6 through the spline 38 through the secondary speed change. The crankshaft 6 and the bearing 7 rotate in the power end housing 5 , Driving the connecting rod body 9, the crosshead 11, and the tie rod 13 to move, transforming the rotary motion of the crankshaft 6 into the reciprocating linear motion of the tie rod 13. The tie rod 13 drives the plunger 18 through the clamp 17 to reciprocate in the valve box 19, thereby Realize the suction of low-pressure liquid and discharge of high-pressure liquid, and realize the pumping of liquid.

Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have Various changes and improvements fall within the scope of the claimed invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims (9)

1. A five-cylinder plunger pump with an integral power end structure includes a power end assembly, a hydraulic end assembly and a reduction box assembly. One end of the power end assembly is connected to the hydraulic end assembly. The other end of the end assembly is connected with the reduction box assembly, and is characterized in that: the power end assembly includes a crankcase, a crosshead box and a spacer, the crankcase and the crosshead box are integrally welded to form the power The end shell, the power end shell is connected with the spacer frame, the power end shell includes a vertical plate, a bearing seat, a front end plate, a rear cover plate, a bottom plate, a support plate and an upper cover plate, the number of the vertical plates is 6 The number of bearing seats is 6, and one vertical plate is connected to one bearing seat. The six vertical plates are arranged in parallel to form a power end cavity. A bottom plate is installed at the bottom of the power end cavity. An upper cover plate is installed on the top of the body, a front end plate is installed at the front end of the power end cavity, a rear cover plate is installed at the rear end of the power end cavity, and a support is provided between two adjacent vertical plates arranged in parallel board.
2. The five-cylinder plunger pump with an integral power end structure according to claim 1, wherein a crankshaft support body is provided at the bottom of the crankcase body, and the crankshaft support body is used to support the crankshaft case body.
3. The five-cylinder plunger pump with an integral power end structure according to claim 1, wherein the bottom of the crosshead box body is provided with a crosshead support body, and the crosshead support body is used to support the crosshead box body .
4. The five-cylinder plunger pump with an integral power end structure according to claim 1, wherein a hydraulic support body is provided at the bottom of the spacer, and the hydraulic support body is used to support the hydraulic end assembly.
5. The five-cylinder plunger pump with an integral power end structure according to claim 1, wherein a crankshaft is provided in the crankcase, the crankshaft is integrally forged from alloy steel, and the crankshaft includes six The shaft journal and five crankshafts are provided with a crankshaft between two adjacent shaft journals. The cylinder spacing of the five-cylinder plunger pump is 13-14 inches.
6. The five-cylinder plunger pump with an integral power end structure according to claim 5, wherein a spline is provided in the crankshaft, and the reduction box assembly is connected with the crankshaft by the spline.
7. The five-cylinder plunger pump with an integral power end structure according to claim 1, wherein a crosshead assembly is provided in the crosshead box, and a connecting rod is provided between the crankcase and the crosshead box. Assembly, a crankshaft is set in the crankcase, one end of the connecting rod assembly is connected to the crankshaft through a connecting rod bearing, the other end of the connecting rod assembly is connected to the crosshead assembly through a crosshead bearing, the connecting rod bearing and the crosshead bearing All steel back bearings with alloy coating.
8. The five-cylinder plunger pump of the integral power end structure according to claim 1, wherein the stroke of the five-cylinder plunger pump of the integral power end structure is 11 inches.
9. The five-cylinder plunger pump with an integral power end structure according to claim 1, wherein the reduction gearbox assembly includes a planetary-stage reduction gearbox and a parallel-stage reduction gearbox, one end of the planetary-stage reduction gearbox and the power The end assembly is connected, the other end of the planetary gearbox is connected with the parallel-stage gearbox, and the two-stage reduction of the gearbox assembly is realized through the planetary gearbox and the parallel-stage gearbox. The reduction ratio is 8:1-15 :1.

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