Method for machining bearing seat of radial tilting pad bearing

Abstract

The invention relates to the technical field of bearing block machining, in particular to a radial tilting pad bearing block machining method which comprises the steps of blanking, rough turning, linear cutting, hardening and tempering, subdivision face milling, drilling, semi-finish turning, drilling, annealing, inner hole laser quenching, annealing, subdivision face accurate grinding, positioning pin hole machining, drilling, finish turning and demagnetization. According to the method, the inner hole laser quenching procedure is added, on the premise that it is guaranteed that the overall hardness of the bearing seat meets the use requirement, the hardness of the inner hole is improved to 45 HRC or above, the machining quality and machining efficiency of the bearing seat are guaranteed, and large deformation and thermal stress formation of the bearing seat cannot be caused by laser local quenching.

Description

Technical Field

[0001] The present application relates to the technical field of bearing seat processing, and in particular to a method for processing a radial tilting pad bearing seat. Background Art

[0002] Radial tilting pad bearings are widely used in high-speed gearboxes, high-speed compressors, high-speed motors, steam turbines, generators, expanders, high-speed pumps, turbochargers, aircraft engines and other fields due to their good stability and large load-bearing capacity.

[0003] Schematic diagram of radial tilting pad bearing structure Figure 1 As shown in the figure, the tilting pad is installed in the inner hole of the bearing seat through the limit hole on the bearing end cover, and the radius of the guide pad back is smaller than the radius of the inner hole of the bearing body. The contact between the guide pad and the bearing seat is a line, that is, line contact, so that the guide pad can swing freely during operation with the speed, load and bearing temperature, thereby forming a wedge-shaped gap and a dynamic pressure oil film to realize the bearing load.

[0004] The guide pad and the bearing seat are the two most critical components in the radial tilting pad bearing. Their processing quality and precision directly determine the quality and precision of the entire bearing. The guide pad and the bearing seat are in line contact, and the contact stress is relatively large. The high-frequency swing of the guide pad during the operation of the bearing as a whole will cause micro-wear at the contact point between the bearing seat and the guide pad. In order to ensure the service life of the bearing, the hardness of the contact surface between the guide pad and the bearing seat needs to be increased as much as possible. The surface hardness of the guide pad and the bearing seat needs to be greater than 45HRC. For high-speed and heavy-load conditions, the surface hardness of the guide pad and the bearing seat needs to be higher. Such a high hardness has a greater impact on the processing quality and efficiency of the bearing seat, especially for the quality and efficiency of small-sized threaded holes and pin holes on the bearing.

[0005] At present, the conventional processing process of bearing seats is as follows: Figure 2 As shown, usually only one quenching and tempering process is included to ensure the quality and efficiency of subsequent processes. However, quenching and tempering alone can usually only achieve a surface hardness of the bearing seat of 260 ~ 300HB, which is far from the hardness requirement of more than 45HRC, and thus the subsequent processing quality and efficiency of the bearing seat cannot be guaranteed. Summary of the invention

[0006] In order to ensure that the bearing seat has a good processing quality and processing efficiency, the present application provides a method for processing a radial tilting pad bearing seat.

[0007] The present application provides a method for processing a radial tilting pad bearing seat, which adopts the following technical solution:

[0008] A method for machining a radial tilting pad bearing seat, comprising:

[0009] S1. Cutting: according to the design drawings and models, use sawing machines and lathes or die forging to quickly punch the steel billet into a blank in the shape of a bearing seat;

[0010] S2, rough turning, placing the blank on the lathe for cutting, removing the excess material on the blank to form a workpiece close to the final shape and size;

[0011] S3, wire cutting, placing the workpiece on the electric spark wire cutting machine to perform precision cutting of the workpiece through the electric spark discharge between the electrode wire and the workpiece;

[0012] S4, quenching and tempering, quenching and tempering the workpiece after wire cutting, preliminarily improving the hardness and strength of the workpiece and improving the mechanical properties of the workpiece;

[0013] S5. Milling the split surface: according to the drawing, use a milling cutter to machine the split surface of the bearing seat on the workpiece;

[0014] S6. Drilling: Drilling screw holes for connecting the upper and lower halves of the bearing seat on the workpiece;

[0015] S7, semi-finishing turning, using a lathe to remove the defects such as knife marks and burrs on the surface of the workpiece after the above steps, while leaving enough margin for finishing turning to reduce the amount of finishing cutting;

[0016] S8, drilling, drilling a circumferential hole of the bearing seat on the workpiece;

[0017] S9, annealing, performing low temperature annealing on the workpiece to remove the internal stress of the workpiece after drilling;

[0018] S10, inner hole laser quenching, laser quenching the inner hole of the workpiece after drilling, and increase the hardness of the inner hole of the workpiece to above 45HRC;

[0019] S11, annealing, performing low temperature annealing on the quenched workpiece to eliminate the internal stress generated during the quenching process;

[0020] S12, fine grinding of the split surface, use a suitable grinding wheel to finely grind the workpiece plane to make the split surface of the bearing seat smooth and flat;

[0021] S13, process the positioning pin holes and drill the positioning pin holes in the upper and lower halves of the bearing seat;

[0022] S14, drilling, drilling a plane hole on the bearing seat;

[0023] S15, fine turning, turning the bearing seat by a fine turning lathe to determine the size and shape of the bearing seat so that the bearing seat can achieve the high precision and surface finish required by the design;

[0024] S16, demagnetization, placing the bearing seat in a DC magnetic field, then gradually changing the direction of the magnetic field, while gradually reducing the magnetic field intensity to zero, to obtain a finished bearing seat.

[0025] By adopting the above technical solution, the inner hole laser quenching process is added. Under the premise of ensuring that the overall hardness of the bearing seat meets the use requirements, the inner hole hardness is increased to above 45HRC, thereby ensuring the processing quality and processing efficiency of the bearing seat, and the laser local quenching will not cause large deformation of the bearing seat and form thermal stress; by adding two stress relief annealing processes, most of the processing stress can be eliminated, and deformation of the bearing seat after fine processing can be avoided; the processing process of the locating pins on the split surfaces of the upper and lower bearings is moved to after the stress relief, thereby ensuring the accuracy of the upper and lower bearing seats after assembly; all drilling processes are moved to before fine turning, thereby avoiding surface bumps and scratches on the bearing seat during processing, clamping and transportation, and greatly improving the apparent quality of the bearing seat.

[0026] Optionally, in the processes S2, S5, S12, etc., a magnetic clamp is used to clamp and fix the blank, and the magnetic clamp is used to magnetize the blank.

[0027] By adopting the above technical solution, the blank is clamped and fixed with a magnetic clamp while being magnetized, so that when the blank is subsequently cut into a bearing body, the bearing body can absorb iron chips, reducing the probability of iron chips generated during cutting work splashing into the working environment; adding a demagnetization process at the end reduces the probability of iron chips being absorbed by the bearing, making it easier to clean the iron chips absorbed by the bearing, reducing the probability of the bearing guide bushing being worn by iron chips in subsequent work, and reducing the risk of bearing wear caused by the absorption of iron chips by the bearing during use.

[0028] Optionally, the magnetic clamp comprises:

[0029] A fixed frame, wherein the fixed frame is arranged on the machine tool;

[0030] A chuck, the chuck being rotatably mounted on a fixed frame;

[0031] A clamping rod, wherein four clamping rods are provided, and the four clamping rods are slidably provided on a fixed frame along a direction close to or away from the center of the chuck, and the four clamping rods are evenly distributed along the circumference of the center of the chuck, and an oblique sliding groove is provided on the chuck, and the clamping rod passes through the sliding groove, and the clamping rod moves close to or away from the center of the chuck along the direction of the sliding groove;

[0032] A rotating motor, wherein the rotating motor is arranged on a fixed frame and an output shaft is connected to the chuck;

[0033] A magnetizing component is arranged on a fixing frame and is used for magnetizing a workpiece clamped by a clamping rod.

[0034] By adopting the above technical solution, the rotating motor is started to drive the chuck to rotate, the rotation of the chuck drives the clamping rod to move, and the four clamping rods move to clamp the blank, so that the position of the blank is fixed by controlling the rotating motor, and then the blank is magnetized by the magnetizing component before cutting, so that the blank can absorb iron chips when cutting.

[0035] Optionally, the magnetizing component includes:

[0036] A magnetizing capacitor, which is arranged on a fixing frame and is connected to a power source;

[0037] A magnetizing coil, wherein the magnetizing coil is arranged on the chuck, and the clamping rod is located in the inner circle of the magnetizing coil;

[0038] A magnetizing switch is arranged on the fixing frame and is connected to both the magnetizing capacitor and the magnetizing coil.

[0039] By adopting the above technical solution, after the magnetizing capacitor is charged, the magnetizing switch is turned on, the magnetizing capacitor passes direct current to the magnetizing coil, and the magnetizing coil generates a stable magnetic field to magnetize the blank, thereby completing the magnetization of the blank.

[0040] Optionally, a cooling mechanism for cooling the workpiece is provided on the fixing frame, and the cooling mechanism includes:

[0041] A cooling pipe, wherein the cooling pipe is arranged on a fixing frame and a cooling liquid flows through the cooling pipe;

[0042] A first liquid pipe, wherein a cooling channel is provided inside the clamp rod, the first liquid pipe is a hose, and two ends of the first liquid pipe are respectively connected to the inside of the cooling pipe and the cooling channel;

[0043] A condensation component is arranged on a fixing frame and is used for exchanging heat with the cooling pipe.

[0044] By adopting the above technical solution, the cooling pipe passes the coolant into the cooling channel inside the clamp rod through the first liquid pipe. The coolant exchanges heat with the workpiece clamped by the clamp rod in the cooling channel, thereby reducing the temperature of the machine tool tool and the workpiece during cutting, reducing the thermal deformation and thermal wear of the tool due to high temperature, thereby extending the service life of the tool, reducing the thermal deformation of the workpiece during the cutting process, and ensuring the accuracy of the processing size.

[0045] Optionally, the condensation component includes:

[0046] Heat exchange fins, wherein a plurality of heat exchange fins are provided, and the plurality of heat exchange fins are evenly distributed on the cooling tube;

[0047] The porous sintered wall is arranged on the inner wall of the cooling tube.

[0048] By adopting the above technical scheme, a plurality of heat exchange fins are arranged on the cooling tube, and the heat dissipation area of ​​the cooling tube is increased by the heat exchange fins, thereby improving the heat dissipation effect of the cooling tube, so that the coolant evaporated after heat exchange with the workpiece can be condensed back into liquid when it is guided back into the cooling tube; a porous sintering wall is arranged on the inner tube wall of the cooling tube, so that the coolant can be evenly distributed on the inner tube wall of the cooling tube along the porous sintering wall, so that the liquid coolant in other positions can be replenished in time after the coolant is heated and evaporated, thereby ensuring the cooling effect.

[0049] Optionally, the cooling tube is arranged in a vertical spiral, and the spiral diameter of the cooling tube gradually decreases from bottom to top, and the heat exchange fins are connected to each spiral section of the cooling tube and are in an inclined state.

[0050] By adopting the above technical solution, the cooling pipe is arranged in a vertical spiral, and the diameter of the spiral cooling pipe gradually decreases from bottom to top. Since the hot air flows upward, the cooling pipes are arranged in a vertically staggered manner, so that each spiral cooling pipe can dissipate heat evenly, and the cold air under the cooling pipe can also evenly exchange heat with the cooling pipes on different sides, so that the gaseous coolant guided out from the cooling channel can be condensed back into liquid when it is guided back into the cooling pipe, so that a stable coolant storage amount is maintained in the cooling pipe at all times, ensuring a continuous supply of coolant to the cooling channel.

[0051] Optionally, the cross-section of the heat exchange fin is in a water drop shape, and the end surface area of ​​one end of the heat exchange fin fixedly contacting the cooling tube is larger than the end surface area of ​​one end of the heat exchange fin away from the cooling tube.

[0052] By adopting the above technical solution, the heat exchange fins are set in a water drop shape, so that the heat exchange fins can provide a larger surface area, increase the contact area with the surrounding air, and facilitate the rapid dissipation of heat. The water drop shape design can guide the airflow to be more evenly distributed on the surface of the heat sink, avoid the formation of vortices or stagnation of airflow in certain areas, and improve the heat dissipation efficiency.

[0053] Optionally, a cooling cavity is opened inside the chuck, and a second liquid pipe is provided on the chuck. The second liquid pipe is also a hose, and the second liquid pipe connects the cooling cavity with the cooling pipe.

[0054] By adopting the above technical solution, a cooling cavity is opened in the chuck, and then the cooling cavity is connected to the cooling pipe through a second liquid pipe. The coolant in the cooling pipe can flow into the cooling cavity in the chuck, so that the workpiece can also be cooled by heat exchange through the chuck, thereby improving the cooling effect on the workpiece.

[0055] Optionally, a temperature sensor is provided on the side surface of the chuck in contact with the workpiece and on the rod end of the clamp rod, a warning light is provided on the fixing frame, and a controller electrically connected to the temperature sensor and the warning light is provided on the fixing frame.

[0056] By adopting the above technical solution, temperature sensors are installed on the chuck and the clamp rod. The temperature sensors sense the temperature of the workpiece and transmit the temperature signal to the controller. When the temperature of the workpiece sensed by the temperature sensor is too high, the controller controls the warning light to light up, warning the staff not to approach the workpiece, thereby reducing the probability of the staff being burned due to accidentally touching the workpiece.

[0057] In summary, the present application includes at least one of the following beneficial technical effects:

[0058] 1. By adding the inner hole laser quenching process, the inner hole hardness is increased to above 45HRC while ensuring that the overall hardness of the bearing seat meets the use requirements, thus ensuring the processing quality and efficiency of the bearing seat, and the local laser quenching will not cause large deformation of the bearing seat and form thermal stress;

[0059] 2. By adding two stress relief annealing processes, most of the processing stress can be eliminated and deformation of the bearing seat after finishing can be avoided;

[0060] 3. By moving the processing steps of the locating pins on the split surfaces of the upper and lower bearings to after stress elimination, the accuracy of the upper and lower bearing seats after assembly is guaranteed; all drilling processes are moved to before fine turning, avoiding surface bumps and scratches on the bearing seats during processing, clamping, and transportation, greatly improving the apparent quality of the bearing seats. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 It is a schematic diagram of the structure of a radial tilting pad support bearing in the background technology of this application; Figure 2 It is a schematic diagram of the conventional processing process flow of the bearing seat in the background technology of this application; Figure 3 It is a schematic diagram of the process of machining a radial tilting pad bearing seat in the present application; Figure 4 is a schematic diagram of the three-dimensional structure of the magnetic clamp in this application; Figure 5 It is a structural schematic diagram of the cooling mechanism and condensing assembly in this application.

[0065] Figure numerals: 1. Magnetic clamp; 11. Fixed frame; 12. Clamping disc; 13. Clamping rod; 14. Rotating motor; 15. Magnetizing assembly; 16. Sliding groove; 17. Temperature sensor; 18. Controller; 19. Warning light; 21. Magnetizing capacitor; 22. Magnetizing coil; 23. Magnetizing switch; 3. Cooling mechanism; 31. Cooling pipe; 32. First liquid pipe; 33. Condensation assembly; 34. Second liquid pipe; 35. Heat exchange fins. DETAILED DESCRIPTION

[0066] The following is combined with Figure 3 -Attached Figure 5 This application is described in further detail.

[0067] An embodiment of the present application discloses a method for machining a bearing seat of a radial tilting pad bearing.

[0068] Reference Figure 3 , the radial tilting pad bearing seat processing method includes S1, blanking, according to the design drawings and models, using a sawing machine and a lathe or a die forging to quickly punch the steel billet into a billet in the shape of the bearing seat;

[0069] S2, rough turning, placing the blank on the lathe for cutting, removing excess material from the blank to form a workpiece close to the final shape and size. The lathe is provided with a magnetic fixture 1, and the blank is fixed in position by the magnetic fixture 1 during cutting, and the magnetic fixture 1 magnetizes the blank; S3, wire cutting, placing the workpiece on the electric spark wire cutting machine to perform precision cutting of the workpiece through electric spark discharge between the electrode wire and the workpiece; S4, tempering, quenching and tempering the workpiece after wire cutting to preliminarily improve the hardness and strength of the workpiece; S5, milling the split surface, according to the drawing, use a milling cutter to process the split surface of the bearing seat on the workpiece; S6, drilling, drilling screw holes connecting the upper and lower halves of the bearing seat on the workpiece; S7, semi-finishing turning, using a lathe to remove tool marks, burrs and other defects on the surface of the workpiece after the above steps, and leaving enough margin for fine turning; S8, drilling, drilling a circular hole of the bearing seat on the workpiece; S9, annealing, low-temperature annealing of the workpiece to remove the workpiece after drilling internal stress; S10, inner hole laser quenching, laser quenching the inner hole of the workpiece after drilling, and increase the hardness of the inner hole of the workpiece to more than 45HRC; S11, annealing, low-temperature annealing of the quenched workpiece to eliminate the internal stress generated during the quenching process; S12, fine grinding of the split surface, select a suitable grinding wheel to finely grind the plane of the workpiece to make the split surface of the bearing seat smooth and flat; S13, machining locating pin holes, drill out the locating pin holes between the upper and lower halves of the bearing seat; S14, drilling, drill out the plane holes on the bearing seat; S15, fine turning, turning the bearing seat through a fine turning lathe, determine the size and shape of the bearing seat, so that the bearing seat can achieve the high precision and surface finish required by the design; S16, demagnetization, place the bearing seat in a DC magnetic field, and then gradually change the direction of the magnetic field, while gradually reducing the magnetic field intensity to zero, to obtain a finished bearing seat.

[0070] Compared with the conventional processing method, the processing method of the present invention has the following advantages: 1. The inner hole laser quenching process is added. On the premise of ensuring that the overall hardness of the bearing seat meets the use requirements, the inner hole hardness is increased to more than 45HRC, thereby ensuring the processing quality and processing efficiency of the bearing seat, and the laser local quenching will not cause large deformation of the bearing seat and form thermal stress; 2. By adding two stress relief annealing processes, most of the processing stress can be eliminated, and deformation of the bearing seat after fine processing can be avoided; 3. The processing process of the locating pins of the upper and lower half bearing split surfaces is moved to after the stress relief, thereby ensuring the accuracy of the upper and lower half bearing seats after assembly; 4. All drilling processes are moved to before fine turning, thereby avoiding surface bumps and scratches on the bearing seat during processing, clamping and transportation, and greatly improving the apparent quality of the bearing seat; 5. Because the magnetic fixture 1 is used to magnetize the bearing body during the processing process, the bearing body can absorb iron filings, which is easy to cause wear of the bearing guide shoe, and the demagnetization process is added to avoid this problem.

[0071] Reference Figure 4and Figure 5 The magnetic clamp 1 includes a fixed frame 11, a chuck 12, a clamping rod 13, a rotating motor 14 and a magnetizing assembly 15. The fixed frame 11 is fixedly mounted on the machine tool. The chuck 12 is rotatably mounted on the fixed frame 11. Four sliding grooves 16 are evenly distributed in the circumferential direction on the side wall of the chuck 12 with the center of the chuck 12 as the center. The sliding grooves 16 are arranged obliquely, with one end of the sliding groove 16 close to the center of the chuck 12 and the other end of the sliding groove 16 close to the edge of the chuck 12.

[0072] Reference Figure 4 and Figure 5 There are four clamping rods 13, and the four clamping rods 13 are slidably mounted on the fixed frame 11 in the direction close to or away from the center of the chuck 12 and are respectively penetrated in four sliding grooves 16. The rotating motor 14 is fixedly mounted on the fixed frame 11 and the output shaft is connected to the center of the chuck 12. The rotating motor 14 is started to drive the chuck 12 to rotate, and the rotation of the chuck 12 drives the clamping rods 13 to move, and the four clamping rods 13 move to clamp the blank, so that the position of the blank is fixed by controlling the rotating motor 14.

[0073] Reference Figure 4 and Figure 5 The magnetizing component 15 is arranged on the fixed frame 11 and is used to magnetize the workpiece clamped by the clamping rod 13. The magnetizing component 15 includes a magnetizing capacitor 21, a magnetizing coil 22 and a magnetizing switch 23. The magnetizing capacitor 21 is fixedly mounted on the fixed frame 11 and is connected to the power supply. The magnetizing coil 22 is fixedly mounted on the side of the chuck 12, and the four clamping rods 13 are all located in the inner circle of the magnetizing coil 22. The magnetizing switch 23 is fixedly mounted on the fixed frame 11 and is connected to both the magnetizing capacitor 21 and the magnetizing coil 22. After the magnetizing capacitor 21 is charged, the magnetizing switch 23 is turned on, and the magnetizing capacitor 21 can pass direct current to the magnetizing coil 22, so that the magnetizing coil 22 generates a stable magnetic field to magnetize the blank.

[0074] Reference Figure 4 and Figure 5 A cooling mechanism 3 for cooling the workpiece is provided on the fixed frame 11, and the cooling mechanism 3 includes a cooling pipe 31, a first liquid pipe 32 and a condensing assembly 33. The cooling pipe 31 is fixedly mounted on the fixed frame 11, and the cooling pipe 31 is arranged to spiral upward in the vertical direction, and the spiral diameter of the cooling pipe 31 gradually decreases from bottom to top. A cooling channel is provided inside the clamping rod 13, and a cooling cavity is provided inside the chuck 12. The first liquid pipe 32 is a hose, and the two ends of the first liquid pipe 32 are respectively connected to the inside of the cooling pipe 31 and the cooling channel. A second liquid pipe 34 is fixedly mounted on the chuck 12, and the second liquid pipe 34 is also a hose, and the second liquid pipe 34 connects the cooling cavity with the cooling pipe 31.

[0075] Reference Figure 4 and Figure 5The cooling pipe 31 passes the coolant into the clamping rod 13 and the chuck 12 through the first liquid pipe 32 and the second liquid pipe 34. The coolant exchanges heat with the workpiece clamped by the clamping rod 13 in the cooling channel and the cooling cavity, thereby reducing the temperature of the machine tool tool and the workpiece during cutting, reducing the thermal deformation and thermal wear of the tool due to high temperature, thereby extending the service life of the tool, reducing the thermal deformation of the workpiece during the cutting process, and ensuring the accuracy of the processing size.

[0076] Reference Figure 4 and Figure 5 The condensation assembly 33 is arranged on the fixing frame 11 and is used to condense the gaseous coolant in the cooling tube 31. The condensation assembly 33 includes a heat exchange fin 35 and a porous sintered wall. The heat exchange fin 35 is provided with a plurality of heat exchange fins 35, and the plurality of heat exchange fins 35 are fixedly mounted on the cooling tube 31 and arranged in an inclined state. The cross section of the heat exchange fin 35 is arranged in a water drop shape. The end surface area of ​​the end of the heat exchange fin 35 fixedly contacting the cooling tube 31 is larger than the end surface area of ​​the end of the heat exchange fin 35 away from the cooling tube 31.

[0077] Reference Figure 4 and Figure 5 The heat exchange fins 35 increase the heat dissipation area of ​​the cooling tube 31 and improve the heat dissipation effect of the cooling tube 31, so that the evaporated coolant after heat exchange with the workpiece can be condensed back into liquid when it is guided back into the cooling tube 31. A porous sintering wall is provided on the inner tube wall of the cooling tube 31, so that the liquid coolant can be evenly distributed on the inner tube wall of the cooling tube 31 along the porous sintering wall, so that the liquid coolant at other positions can be replenished in time after the coolant is heated and evaporated, thereby ensuring the cooling effect.

[0078] Reference Figure 4 and Figure 5 A temperature sensor 17 is fixedly mounted on the side of the chuck 12 that contacts the workpiece and the rod end of the clamp rod 13. A warning light 19 is fixedly mounted on the fixing frame 11, and a controller 18 electrically connected to the temperature sensor 17 and the warning light 19 is provided on the fixing frame 11. The temperature sensor 17 senses the temperature of the workpiece and transmits a temperature signal to the controller 18. When the temperature of the workpiece sensed by the temperature sensor 17 is too high, the controller 18 controls the warning light 19 to light up, warning the staff not to approach the workpiece, thereby reducing the probability of the staff being burned due to accidentally touching the workpiece.

[0079] The working principle of the embodiment of the present application is as follows:

[0080] By adding the inner hole laser quenching process, the inner hole hardness is increased to above 45HRC while ensuring that the overall hardness of the bearing seat meets the use requirements, thus ensuring the processing quality and efficiency of the bearing seat, and the laser local quenching will not cause large deformation of the bearing seat and form thermal stress; by adding two stress relief annealing processes, most of the processing stress can be eliminated to avoid deformation of the bearing seat after fine machining; the positioning pin processing process of the upper and lower bearing split surfaces is moved to after stress relief, ensuring the accuracy of the upper and lower bearing seats after assembly; all drilling processes are moved to before fine turning, avoiding surface bumps and scratches on the bearing seat during machining, clamping and transportation, greatly improving the apparent quality of the bearing seat.

[0081] 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 method for machining a radial tilting pad bearing seat, characterized in that: include: S1. Cutting: according to the design drawings and models, use sawing machines and lathes or die forging to quickly punch the steel billet into a blank in the shape of a bearing seat; S2, rough turning, placing the blank on the lathe for cutting, removing the excess material on the blank to form a workpiece close to the final shape and size; S3, wire cutting, placing the workpiece on the electric spark wire cutting machine to perform precision cutting of the workpiece through the electric spark discharge between the electrode wire and the workpiece; S4, quenching and tempering, quenching and tempering the workpiece after wire cutting, preliminarily improving the hardness and strength of the workpiece and improving the mechanical properties of the workpiece; S5. Milling the split surface: according to the drawing, use a milling cutter to machine the split surface of the bearing seat on the workpiece; S6. Drilling: Drilling screw holes for connecting the upper and lower halves of the bearing seat on the workpiece; S7, semi-finishing turning, using a lathe to remove the defects such as knife marks and burrs on the surface of the workpiece after the above steps, while leaving enough margin for finishing turning to reduce the amount of finishing cutting; S8, drilling, drilling a circumferential hole of the bearing seat on the workpiece; S9, annealing, performing low temperature annealing on the workpiece to remove the internal stress of the workpiece after drilling; S10, inner hole laser quenching, laser quenching the inner hole of the workpiece after drilling, and increase the hardness of the inner hole of the workpiece to above 45HRC; S11, annealing, performing low temperature annealing on the quenched workpiece to eliminate the internal stress generated during the quenching process; S12, fine grinding of the split surface, use a suitable grinding wheel to finely grind the workpiece plane to make the split surface of the bearing seat smooth and flat; S13, process the positioning pin holes and drill the positioning pin holes in the upper and lower halves of the bearing seat; S14, drilling, drilling a plane hole on the bearing seat; S15, fine turning, turning the bearing seat by a fine turning lathe to determine the size and shape of the bearing seat so that the bearing seat can achieve the high precision and surface finish required by the design; S16, demagnetization, placing the bearing seat in a DC magnetic field, then gradually changing the direction of the magnetic field, while gradually reducing the magnetic field intensity to zero, to obtain a finished bearing seat.

2. A method for machining a radial tilting pad bearing seat according to claim 1, characterized in that: When cutting the blank in S2, a magnetic clamp (1) is used to clamp and fix the blank, and the magnetic clamp (1) magnetizes the blank.

3. A method for machining a radial tilting pad bearing seat according to claim 2, characterized in that: The magnetic clamp (1) comprises: A fixed frame (11), wherein the fixed frame (11) is arranged on a machine tool; A chuck (12), wherein the chuck (12) is rotatably mounted on the fixed frame (11); A clamping rod (13), wherein four clamping rods (13) are provided, and the four clamping rods (13) are slidably provided on the fixed frame (11) in a direction close to or away from the center of the chuck (12); the four clamping rods (13) are evenly distributed circumferentially along the center of the chuck (12); an oblique sliding groove (16) is provided on the chuck (12); the clamping rod (13) passes through the sliding groove (16), and the clamping rod (13) moves close to or away from the center of the chuck (12) in the direction of the sliding groove (16); A rotating motor (14), wherein the rotating motor (14) is arranged on the fixing frame (11) and the output shaft is connected to the chuck (12); A magnetizing component (15) is arranged on a fixing frame (11) and is used for magnetizing a workpiece clamped by a clamping rod (13).

4. A method for machining a radial tilting pad bearing seat according to claim 3, characterized in that: The magnetizing component (15) comprises: A magnetizing capacitor (21), wherein the magnetizing capacitor (21) is disposed on the fixing frame (11) and is connected to a power source; A magnetizing coil (22), wherein the magnetizing coil (22) is disposed on the chuck (12), and the clamping rod (13) is located in the inner circle of the magnetizing coil (22); A magnetizing switch (23) is arranged on the fixing frame (11) and is connected to both the magnetizing capacitor (21) and the magnetizing coil (22).

5. The method for machining a radial tilting pad bearing seat according to claim 3, characterized in that: The fixing frame (11) is provided with a cooling mechanism (3) for cooling the workpiece, and the cooling mechanism (3) comprises: A cooling pipe (31), wherein the cooling pipe (31) is arranged on the fixing frame (11), and a cooling liquid flows through the cooling pipe (31); A first liquid passage pipe (32), wherein a cooling channel is provided inside the clamping rod (13), the first liquid passage pipe (32) is a hose, and both ends of the first liquid passage pipe (32) are respectively connected to the inside of the cooling pipe (31) and the cooling channel; A condensation component (33) is arranged on the fixing frame (11) and is used to condense the gaseous cooling liquid in the cooling pipe (31).

6. A method for machining a radial tilting pad bearing seat according to claim 5, characterized in that: The condensation component (33) comprises: Heat exchange fins (35), wherein a plurality of heat exchange fins (35) are provided, and the plurality of heat exchange fins (35) are evenly distributed on the cooling tube (31); A porous sintered wall, wherein the porous sintered wall is arranged on the inner wall of the cooling tube (31).

7. A method for machining a radial tilting pad bearing seat according to claim 6, characterized in that: The cooling tube (31) is arranged to spiral upward in a vertical direction, and the spiral diameter of the cooling tube (31) gradually decreases from bottom to top. The heat exchange fins (35) are connected to each spiral section of the cooling tube (31) and are in an inclined state.

8. A method for machining a radial tilting pad bearing seat according to claim 7, characterized in that: The cross section of the heat exchange fin (35) is arranged in a water drop shape, and the end surface area of ​​the end of the heat exchange fin (35) fixedly contacting the cooling tube (31) is larger than the end surface area of ​​the end of the heat exchange fin (35) away from the cooling tube (31).

9. A method for machining a radial tilting pad bearing seat according to claim 5, characterized in that: A cooling cavity is provided inside the chuck (12). A second liquid passage (34) is provided on the chuck (12). The second liquid passage (34) is also a hose. The second liquid passage (34) connects the cooling cavity with the cooling pipe (31).

10. The method for machining a radial tilting pad bearing seat according to claim 3, characterized in that: A temperature sensor (17) is provided on the side surface of the chuck (12) in contact with the workpiece and on the rod end of the clamp rod (13); a warning light (19) is provided on the fixing frame (11); and a controller (18) electrically connected to the temperature sensor (17) and the warning light (19) is provided on the fixing frame (11).

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