Forged crankshaft for slurry pump

Abstract

The invention provides a forged crankshaft for a slurry pump, belongs to the technical field of parts at the power end of the slurry pump, and mainly aims at solving the problems that an existing cast crankshaft can only be integrally cast and integrally machined and is high in energy consumption, high in manufacturing cost and short in service life. Each group of mounting connection positions comprises six arcs and six planes, the corresponding angle between each arc and each plane is 30 degrees, a flange is arranged on the main shaft, a third crank is arranged at one end of the flange, a second crank is arranged at the other end of the flange, a first crank is arranged at one end, far away from the flange, of the second crank, and two groups of bearing positions are respectively arranged at two ends of the main shaft; a fastening assembly is arranged on the main shaft; the forged crankshaft adopts a novel process of split forging and split machining, all parts can be arranged at the corresponding positions of the main shaft in a hot charging mode after machining is completed, the parts can be replaced at will, maintenance is convenient, the manufacturing cost is reduced, and convenience is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of power end parts of a mud pump, and more specifically, particularly relates to a forged crankshaft used for a mud pump. Background Art

[0002] As a key equipment in the process of oil and gas extraction, mud pumps play a relatively important role in various links such as exploration, drilling, and production. Mud pumps are mainly driven by hydraulics to pump mud and other materials to underground pipelines or wellheads, providing necessary power support for the entire oil and gas field operation. The crankshaft of the mud pump, as one of its core components, is the hub for the mud pump to transmit power.

[0003] For example, the Chinese utility model patent with patent number CN202220704853.3 provides a multi-cylinder mud pump crankshaft, which adopts an integrated forging structure with five cranks and six supports, which improves the crankshaft load-bearing strength and rigidity, reduces the crankshaft weight, and improves the reliability and economy of the power end. The displacement of a single mud pump can be increased by changing the input type of crankshaft power and increasing the number of cranks.

[0004] However, when processing traditional cast crankshafts, only the overall casting and overall processing production process can be adopted. The casting process consumes a lot of materials and has a low yield rate. Moreover, after the traditional cast crankshaft is processed and put into use, once it is damaged, it cannot be repaired and can only be replaced, which is less convenient. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a forged crankshaft for a mud pump to solve the technical problems in the prior art that the traditional cast crankshaft has a high scrap rate and can only be produced by integral casting and integral processing, the casting process consumes a lot of materials, the production cycle is long, the cost is high, and the convenience is low.

[0006] The purpose and effect of the forged crankshaft for a mud pump of the present invention are achieved by the following specific technical means:

[0007] A forged crankshaft for a mud pump includes a main shaft, four groups of mounting connection positions are provided on the surface of the main shaft, each group of the mounting connection positions includes six arcs and six planes, and the angles corresponding to each arc and the plane are 30°. A flange is provided on the main shaft, a third crank is provided at one end of the flange, a second crank is provided at the other end of the flange, a first crank is provided at the end of the second crank away from the flange, the first crank, the second crank, the third crank and the flange are all interference connected with the outer wall of the main shaft, two groups of bearing positions are provided at both ends of the main shaft, and a fastening component is provided on the main shaft.

[0008] As a further solution of the present invention, the fastening assembly includes two groups of first fastening sleeves, a second fastening sleeve, a third fastening sleeve and a fourth fastening sleeve, and two groups of the first fastening sleeves are respectively arranged at both ends of the main shaft, one group of the first fastening sleeves is arranged at the end of the first crank away from the flange, the second fastening sleeve is arranged between the first crank and the second crank, the third fastening sleeve and the fourth fastening sleeve are arranged between the second crank and the third crank, and the other group of the first fastening sleeves is arranged at the end of the third crank away from the flange.

[0009] As a further solution of the present invention, the fourth fastening sleeve is arranged between the flange and the third crank, the third fastening sleeve is arranged between the flange and the second crank, and the two groups of the first fastening sleeve, the second fastening sleeve, the third fastening sleeve and the fourth fastening sleeve are all interference connected with the outer wall of the main shaft.

[0010] As a further solution of the present invention, the two groups of bearing positions are both arranged at an end of the first fastening sleeve away from the flange.

[0011] As a further solution of the present invention, the flange, the first crank, the second crank and the third crank all correspond to the installation connection position, and the six arcs and the six planes are arranged in sequence along the circumferential direction.

[0012] As a further solution of the present invention, the flange is provided with a central through inner hole, and the first crank, the second crank and one end of the third crank are provided with eccentric through inner holes, the central through inner hole and the three groups of eccentric through inner holes are all regular in shape, the flange is interference connected with the main shaft through the central through inner hole, and the first crank, the second crank and the third crank are interference connected with the main shaft through the eccentric through inner holes.

[0013] As a further solution of the present invention, the first crank, the second crank, one end of the third crank and both end surfaces of the main shaft are respectively provided with a plurality of accessory connection holes, and the flange is provided with a plurality of through holes.

[0014] As a further solution of the present invention, the plurality of groups of accessory connection holes are all threaded blind holes.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The forged crankshaft can process the main shaft, flange, three cranks and five fastening sleeves in single-piece forging. After processing, the forged crankshaft can be assembled into a finished product by hot assembly. Compared with the traditional overall processing of cast crankshafts, separate forging and processing can enhance the material strength of each component and extend the service life of the forged crankshaft. In addition, materials can be saved when processing components separately, reducing the consumption of processing materials, thus solving the problem of high material consumption and low yield rate in the casting process of traditional cast crankshafts.

[0017] 2. After the forged crankshaft is processed and put into use, when the user needs to repair the forged crankshaft, the main shaft, flange, fastening sleeve, crank and other parts can be disassembled at will, and then each part can be repaired or replaced separately, which solves the problem that it is inconvenient for users to repair the cast crankshaft and improves convenience. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a cross-sectional view of a forged crankshaft for a mud pump according to the present invention;

[0019] Figure 2 It is a cross-sectional view of a main shaft in a forged crankshaft for a mud pump according to the present invention;

[0020] Figure 3 It is a schematic structural diagram of a main shaft in a forged crankshaft for a mud pump according to the present invention;

[0021] Figure 4 It is a cross-sectional view of a first fastening sleeve in a forged crankshaft for a mud pump according to the present invention;

[0022] Figure 5 It is a cross-sectional view of the second fastening sleeve in the forged crankshaft of the mud pump of the present invention;

[0023] Figure 6 It is a cross-sectional view of the third fastening sleeve in the forged crankshaft for a mud pump of the present invention;

[0024] Figure 7 is a cross-sectional view of a fourth fastening sleeve in a forged crankshaft for a mud pump according to the present invention;

[0025] Figure 8 It is a front view of a first crank in a forged crankshaft for a mud pump of the present invention;

[0026] Fig. 9 is a cross-sectional view of a first crank in a forged crankshaft for a mud pump of the present invention;

[0027] Fig.10 It is a front view of the second crank in the forged crankshaft for a mud pump of the present invention;

[0028] Fig.11is a cross-sectional view of a second crank in a forged crankshaft for a mud pump according to the present invention;

[0029] Fig.12 It is a front view of the third crank in the forged crankshaft for a mud pump of the present invention;

[0030] Fig.13 is a cross-sectional view of a third crank in a forged crankshaft for a mud pump of the present invention;

[0031] Fig.14 It is a front view of a flange in a forged crankshaft used for a mud pump according to the present invention;

[0032] Fig.15 It is a cross-sectional view of a flange in a forged crankshaft used for a mud pump according to the present invention.

[0033] In the figure, the corresponding relationship between the component names and the figure numbers is as follows:

[0034] 100. spindle; 101. first fastening sleeve; 102. second fastening sleeve; 103. third fastening sleeve; 104. fourth fastening sleeve; 106. first crank; 107. second crank; 108. third crank; 109. flange; 110. bearing seat; 111. arc; 112. plane. DETAILED DESCRIPTION

[0035] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the technical solutions of the present invention, but cannot be used to limit the protection scope of the present invention.

[0036] Example:

[0037] As attached Figures 1 to 15 As shown:

[0038] The forged crankshaft for a mud pump includes a main shaft 100. The main shaft 100 has four groups of mounting connection positions on its surface. The four groups of mounting connection positions are used to mount a flange 109, a first crank 106, a second crank 107 and a third crank 108, respectively. Each group of mounting connection positions includes six arcs 111 and six planes 112. The six arcs 111 and the six planes 112 of each group of mounting connection positions are arranged in equal parts in the circumferential direction. When processing, the outer diameter of the main shaft 100 can be divided into 12 equal parts. One of the planes 112 is processed at an angle of 30 degrees every 60 degrees, and the processing tolerance of this position is ±0.025 wire. The circumference is equally divided into six planes 112 and six arcs 111. The six arcs 111 in the installation connection position provide a positioning basis for the installation of subsequent parts, and the six planes 112 provide a connection basis for the installation of subsequent parts. The six planes 112 replace the traditional keyway connection, and its ability to resist torque and impact force far exceeds that of the keyway connection. A flange 109 is provided on the spindle 100. A third crank 108 is provided at one end of the flange 109, a second crank 107 is provided at the other end of the flange 109, and a first crank 106 is provided at one end of the second crank 107 away from the flange 109. The first crank 106, the second crank 107, the third crank 108 and the flange 109 are all connected with the outer wall of the main shaft 100 by interference fit. The interference fit between the first crank 106, the second crank 107, the third crank 108 and the flange 109 and the main shaft 100 ensures that the mud pump can stably transmit power and withstand the load when working. Torque and impact force, two groups of bearing positions 110 are respectively arranged at both ends of the main shaft 100, and the two groups of bearing positions 110 are arranged at the end of the first fastening sleeve 101 away from the flange 109. The bearing position 110 is used to install bearings. After the bearings are installed, they are connected and fixed with the bearing positions of the external crankcase. The two groups of bearings can effectively reduce the friction resistance of the main shaft 100 during rotation, reduce energy loss, and improve the rotation accuracy and stability of the forged crankshaft, thereby ensuring that the mud pump can continue to operate reliably under a long-term, high-intensity working environment.

[0039] The main shaft 100 is provided with a fastening assembly, which includes two groups of first fastening sleeves 101, a second fastening sleeve 102, a third fastening sleeve 103 and a fourth fastening sleeve 104. Two groups of first fastening sleeves 101 are respectively provided at both ends of the main shaft 100, one group of first fastening sleeves 101 is provided at one end of the first crank 106 away from the flange 109, the second fastening sleeve 102 is provided between the first crank 106 and the second crank 107, the third fastening sleeve 103 and the fourth fastening sleeve 104 are provided between the second crank 107 and the third crank 108, and the other group of first fastening sleeves 101 is provided at one end of the third crank 108 away from the flange 109, through which The cooperation of a group of first fastening sleeves 101 and a fourth fastening sleeve 104 can prevent the third crank 108 from being displaced during operation. The cooperation of the fourth fastening sleeve 104 and the third fastening sleeve 103 can prevent the flange 109 from being displaced during operation. The cooperation of the third fastening sleeve 103 and the second fastening sleeve 102 can prevent the second crank 107 from being displaced during operation. The cooperation of the second fastening sleeve 102 and another group of first fastening sleeves 101 can prevent the first crank 106 from being displaced during operation. The setting of these fastening sleeves ensures the axial and radial stability of the forged crankshaft during operation.

[0040] The fourth fastening sleeve 104 is arranged between the flange 109 and the third crank 108, and the third fastening sleeve 103 is arranged between the flange 109 and the second crank 107. The two groups of the first fastening sleeve 101, the second fastening sleeve 102, the third fastening sleeve 103 and the fourth fastening sleeve 104 are all interference connected with the outer wall of the main shaft 100. The first fastening sleeve 101, the second fastening sleeve 102, the third fastening sleeve 103 and the fourth fastening sleeve 104 are all provided with fastening inner holes in the center. These fastening inner holes enable these fastening sleeves to be sleeved on the main shaft 100, and when the first fastening sleeve 101, the second fastening sleeve 102, the third fastening sleeve 103 and the fourth fastening sleeve 104 are assembled on the main shaft 100, the interference is controlled to be about 15 threads.

[0041] A central through inner hole is provided at the center of the flange 109, and an eccentric through inner hole is provided at one end of the first crank 106, the second crank 107, and the third crank 108. The central through inner hole and the three sets of eccentric through inner holes are all in regular shape. The flange 109 is connected to the main shaft 100 through the central through inner hole by interference fit. The first crank 106, the second crank 107, and the third crank 108 are connected to the main shaft 100 through the eccentric through inner holes by interference fit. The central through inner hole and the eccentric through inner hole correspond to the shapes of the mounting connection positions of the outer wall of the main shaft 100. 9. The inner diameter circumference of the four positions of the first crank 106, the second crank 107 and the third crank 108 is equally divided into 12 parts, each part is 30 degrees, and an identical plane 112 or arc 111 is processed every 60 degrees, and the circumference of the inner hole is equally divided into six planes 112 and six arcs 111, so that these inner holes correspond to the six planes 112 and six arcs 111 of the outer wall of the main shaft 100, and the flange 109, the first crank 106, the second crank 107 and the third crank 108 are all interference connected with the main shaft 100 through the through inner hole.

[0042] Among them, the main shaft 100, the third crank 108, the fourth fastening sleeve 104, the flange 109, the third fastening sleeve 103, the second crank 107, the second fastening sleeve 102, the first crank 106 and the two first fastening sleeves 101 are all forged with 35Crmo material and are hot assembled after rough machining, normalizing, tempering and finishing.

[0043] When the flange 109, the first crank 106, the second crank 107, the third crank 108, the two first fastening sleeves 101, the second fastening sleeve 102, the third fastening sleeve 103, the fourth fastening sleeve 104 and the main shaft 100 are all processed, the flange 109, the first crank 106, the second crank 107, the third crank 108 and the five fastening sleeves can be placed in an external heating furnace and heated to about 150-180 degrees Celsius to expand the inner hole to an ideal size, so as to facilitate the flange 109, the first crank 106, the second crank 107, the third crank 108 and the five fastening sleeves to be hot-mounted.

[0044] Furthermore, the heated parts are installed on the main shaft 100 in order: the installation of the forged crankshaft starts from the direction of the third crank 108, and the order is from large to small according to the diameter of the main shaft 100: 1. the third fastening sleeve 103, 2. the flange 109, 3. the fourth fastening sleeve 104, 4. the third crank 108, 5. the first fastening sleeve 101. After the installation of this side is completed, the other side is installed: the installation order is 1. the second crank 107, 2. the second fastening sleeve 102, 3. the first crank 106, 4. the first fastening sleeve 101. From then on, the assembly is complete. After the assembled crankshaft cools down to room temperature, the crankshaft is clamped on the machine tool and the bearing positions 110 at both ends are aligned and processed using the double center.

[0045] It can be understood that during the thermal assembly process, the inner hole parts to be assembled are heated to expand due to the heat, and the size of the inner hole increases. When the size of the inner hole expands to be larger than the outer diameter of the shaft parts that match it, the shaft parts are quickly installed into the inner hole. After the parts cool down, the inner hole shrinks and is tightly clamped on the shaft, thereby achieving a tight and firm fit and achieving the effect of interference fit, ensuring that the parts will not easily loosen or move during operation, and ensuring the stability and reliability of the connection.

[0046] By adopting the hot assembly method, for some fits with large interference, if cold assembly is used, very large assembly force may be required, and even parts may be damaged. Hot assembly expands the inner hole by heating, which greatly reduces the external force required for assembly, makes the assembly process easier to operate, and reduces the requirements for equipment and tools. The tight fit formed by hot assembly makes the bonding force between parts stronger, and can effectively transmit force when bearing working loads, and is not prone to loosening, slipping and other phenomena, which improves the reliability and stability of the connection and extends the service life of the forged crankshaft.

[0047] The inner diameters of the first crank 106, the second crank 107, the third crank 108 and the flange 109 are set according to the mud pump model and the main shaft 100. One end of the first crank 106, the second crank 107 and the third crank 108 and the two end surfaces of the main shaft 100 are respectively provided with a plurality of threaded blind holes for connecting accessories. One end of the flange 109 is provided with a plurality of through holes. Both sets of bearing positions 110 are interference connected with the outer wall of the main shaft 100.

[0048] The forged crankshaft can process all the above-mentioned parts such as the first fastening sleeve 101, the second fastening sleeve 102, and the third fastening sleeve 103 separately. During the separate processing, each part can adopt a more suitable processing technology and parameters according to its own structural characteristics and performance requirements, so as to maximize the optimization of the material structure and enhance the material strength. After the processing is completed, the forged crankshaft can be assembled into a finished product by hot assembly. Compared with the traditional overall processing of the cast crankshaft, it can not only improve the quality of each part, but also extend the service life of the forged crankshaft, and it is more efficient in material use, avoiding excessive waste of materials caused by taking into account all parts during the overall processing, thereby greatly reducing the consumption of processing materials, and solving the problem of high material consumption in the casting process of the traditional cast crankshaft. After the forged crankshaft is processed and put into use, when the user needs to repair the forged crankshaft, there is no need to use complex special tools or use destructive methods. All parts can be disassembled in a certain order and specification, and then each part can be repaired or replaced separately, which solves the problem that it is inconvenient for users to repair the cast crankshaft and improves convenience.

[0049] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. Forged crankshaft for mud pump, characterized by: The invention comprises a main shaft (100), wherein the main shaft (100) is provided with four groups of installation connection positions on its surface, each group of the installation connection positions comprises six arcs (111) and six planes (112), and the angles corresponding to each arc (111) and the plane (112) are all 30°. The main shaft (100) is provided with a flange (109), one end of the flange (109) is provided with a third crank (108), and the other end of the flange (109) is provided with a There is a second crank (107), and a first crank (106) is arranged at one end of the second crank (107) away from the flange (109); the first crank (106), the second crank (107), the third crank (108) and the flange (109) are all interference-connected with the outer wall of the main shaft (100); two groups of bearing positions (110) are respectively arranged at both ends of the main shaft (100), and a fastening component is arranged on the main shaft (100).

2. The forged crankshaft for a mud pump according to claim 1, characterized in that: The fastening assembly comprises two groups of a first fastening sleeve (101), a second fastening sleeve (102), a third fastening sleeve (103) and a fourth fastening sleeve (104); two groups of the first fastening sleeves (101) are respectively arranged at two ends of the main shaft (100); one group of the first fastening sleeves (101) is arranged at an end of the first crank (106) away from the flange (109); the second fastening sleeve (102) is arranged between the first crank (106) and the second crank (107); the third fastening sleeve (103) and the fourth fastening sleeve (104) are arranged between the second crank (107) and the third crank (108); and the other group of the first fastening sleeves (101) is arranged at an end of the third crank (108) away from the flange (109).

3. The forged crankshaft for a mud pump according to claim 2, characterized in that: The fourth fastening sleeve (104) is arranged between the flange (109) and the third crank (108), the third fastening sleeve (103) is arranged between the flange (109) and the second crank (107), and the two groups of the first fastening sleeve (101), the second fastening sleeve (102), the third fastening sleeve (103) and the fourth fastening sleeve (104) are all interference-connected with the outer wall of the main shaft (100).

4. The forged crankshaft for a mud pump according to claim 2, characterized in that: The two groups of bearing positions (110) are both arranged at an end of the first fastening sleeve (101) away from the flange (109).

5. The forged crankshaft for a mud pump according to claim 1, characterized in that: The flange (109), the first crank (106), the second crank (107) and the third crank (108) all correspond to the installation connection position, and the six arcs (111) and the six planes (112) are arranged in sequence along the circumferential direction.

6. The forged crankshaft for a mud pump according to claim 1, characterized in that: The flange (109) is provided with a central through inner hole, and one end of the first crank (106), the second crank (107) and the third crank (108) are provided with an eccentric through inner hole, and the central through inner hole and the three groups of eccentric through inner holes are all of regular shape. The flange (109) is interference-connected with the main shaft (100) through the central through inner hole, and the first crank (106), the second crank (107) and the third crank (108) are interference-connected with the main shaft (100) through the eccentric through inner holes.

7. The forged crankshaft for a mud pump according to claim 1, characterized in that: The first crank (106), the second crank (107), one end of the third crank (108) and both end surfaces of the main shaft (100) are respectively provided with a plurality of groups of accessory connection holes, and the flange (109) is provided with a plurality of groups of through holes.

8. The forged crankshaft for a mud pump according to claim 7, characterized in that: The plurality of groups of accessory connection holes are all threaded blind holes.

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