A method for polishing the inner wall of a nickel-titanium alloy thick tube

Abstract

The present application relates to a kind of inner wall polishing method of nickel-titanium alloy thick pipe, first to be polished nickel-titanium alloy thick pipe is ultrasonic decontamination cleaning and drying, then the nickel-titanium alloy thick pipe to be polished after drying is placed into rotating rigid grinding device, and in the inside of nickel-titanium alloy thick pipe to be polished, fill coarse-grained grinding medium and water, start rotating rigid grinding device to nickel-titanium alloy thick pipe to be polished and carry out rough polishing, again after nickel-titanium alloy thick pipe to be polished and carried out rough polishing, it is placed into rotating flexible grinding device, and start rotating flexible grinding device using polishing liquid to nickel-titanium alloy thick pipe to be polished and carry out fine polishing, finally after nickel-titanium alloy thick pipe to be polished and carried out fine polishing, it is ultrasonic water cleaning and drying.The present application is combined with the way of rotating rigid grinding device rough polishing and the way of rotating flexible grinding device fine polishing to realize automatic polishing, can effectively remove the inner wall defect of nickel-titanium alloy thick pipe, reduce inner wall surface roughness, improve smoothness and polishing efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of metal material processing, in particular to a nickel-titanium alloy rough pipe inner wall polishing method. BACKGROUND

[0002] Nickel-titanium alloy is a shape memory alloy, which can automatically restore the plastic deformation to the original shape at a certain temperature, has good plasticity, wear resistance, corrosion resistance, high damping and super-elasticity, and excellent biocompatibility, and has wide application prospects in medical devices, aerospace, petroleum chemical industry and other fields.

[0003] The nickel-titanium alloy rough pipe is a nickel-titanium alloy pipe with an inner hole diameter of 9mm-100mm and a wall thickness greater than or equal to 0.1mm. The processing of nickel-titanium alloy rough pipe, which is a material with special physical and chemical properties, is particularly complex and requires extremely high requirements. After the nickel-titanium alloy rough pipe is processed to the final size, the inner wall surface will usually leave mechanical processing marks, such as scratches, burrs, roughness and the like. These defects not only affect the overall appearance of the pipe, but more importantly, they increase the resistance to fluid flow in the pipe during use, increase friction and wear, and even cause unnecessary irritation or damage to the contact position of the pipe. In the field of medical devices, these problems are particularly critical, and any minor surface defect can adversely affect the medical effect and even cause safety hazards. The traditional nickel-titanium alloy rough pipe inner hole processing method, including manual polishing and sand blasting, can improve the inner hole surface quality to a certain extent, but the traditional method has low efficiency, poor precision and is easy to damage the pipe during polishing and sand blasting. SUMMARY

[0004] Therefore, it is necessary to provide a nickel-titanium alloy rough pipe inner wall polishing method to solve the above technical problems, which has the characteristics of high efficiency, not easy to damage the pipe and can realize uniform polishing of the nickel-titanium alloy rough pipe inner wall and improve the polishing precision.

[0005] The present application provides a nickel-titanium alloy rough pipe inner wall polishing method, which comprises the following steps:

[0006] The nickel-titanium alloy rough pipe to be polished is subjected to ultrasonic decontamination cleaning and drying;

[0007] The dried nickel-titanium alloy rough pipe to be polished is placed in a rotary rigid grinding device, and the nickel-titanium alloy rough pipe to be polished is filled with coarse-grained grinding medium and water, and the rotary rigid grinding device is started to coarsely polish the nickel-titanium alloy rough pipe to be polished;

[0008] The nickel-titanium alloy rough pipe after coarse polishing is placed in a rotary flexible grinding device, and the rotary flexible grinding device is started to finely polish the nickel-titanium alloy rough pipe to be polished with polishing liquid;

[0009] The fine-polished nickel-titanium alloy thick tube is ultrasonically cleaned with water and dried.

[0010] In one embodiment, the coarse-grit grinding medium is quartz sand with a particle size of 400-1200 mesh, and the polishing liquid is prepared by mixing chromium oxide polishing powder, aluminum oxide polishing powder, and water in a mass ratio of 1:1:5-10, and the particle size of the chromium oxide polishing powder and the aluminum oxide polishing powder is 10-40 μm.

[0011] In one embodiment, the rotary rigid grinding device is provided with a cylindrical first inner liner that can be tightly sleeved on the outside of the nickel-titanium alloy thick tube to be polished, a first sleeve with a closed bottom, and an axial helical blade assembly that can rotate around the axis of the first sleeve. The first sleeve is sleeved on the outside of the first inner liner, and the axial helical blade assembly is arranged inside the first inner liner. The axis of the axial helical blade assembly coincides with the axis of the first sleeve. There is a horizontal gap between the axial helical blade assembly and the inner wall of the nickel-titanium alloy thick tube to be polished. The width of the gap is greater than the thickness of the tube wall of the nickel-titanium alloy thick tube to be polished.

[0012] In one embodiment, the rotary flexible grinding device is provided with a cylindrical second inner liner that can be tightly sleeved on the outside of the nickel-titanium alloy thick tube to be polished, a second sleeve with a closed bottom, and an axial cloth wheel rotating assembly that can rotate around the axis of the second sleeve. The second sleeve is sleeved on the outside of the second inner liner, and the axial cloth wheel rotating assembly is arranged inside the second sleeve. The axis of the axial cloth wheel rotating assembly coincides with the axis of the second sleeve. The maximum rotating diameter of the axial cloth wheel rotating assembly is equal to the inner diameter of the nickel-titanium alloy thick tube to be polished.

[0013] In one embodiment, the rotary rigid grinding device and the rotary flexible grinding device are both provided with a lifting mechanism. The lifting mechanism is provided with an upper base plate, a plurality of support columns, a lower base plate, a guide rail, an upper lifting block, and a lower lifting block.

[0014] The upper base plate and the lower base plate are parallel and fixedly connected in a vertical arrangement on the upper and lower ends of the plurality of support columns. The guide rail is fixedly arranged vertically in the middle of the upper base plate and the lower base plate.

[0015] The upper lifting block and the lower lifting block are both sleeved on the guide rail and can slide up and down along the guide rail.

[0016] The top of the lower base plate is provided with a circular groove, and two mounting keys are horizontally arranged inside the circular groove.

[0017] In one embodiment, the height of the first inner liner and the second inner liner is equal to the length of the nickel-titanium alloy thick tube to be polished. The first inner liner and the second inner liner each include an upper inner liner and a lower inner liner. The upper inner liner is fixedly connected to the top of the lower inner liner. The height of the upper inner liner and the height of the lower inner liner are in a ratio of 1:16-19.

[0018] The side wall of the lower inner liner is uniformly provided with a plurality of first through holes in the axial direction, each of which vertically penetrates the side wall of the lower inner liner, and the side wall of the lower inner liner is provided with a plurality of groups of second through holes in the radial direction, the number of which is equal to that of the first through holes, each group of second through holes includes a plurality of second through holes uniformly distributed in the vertical direction, each of which radially penetrates the side wall of the lower inner liner, and each first through hole communicates with all the second through holes in a group of second through holes;

[0019] The upper inner liner is provided with a groove ring in the middle of the bottom, and each first through hole communicates with the groove ring;

[0020] The side wall of the upper inner liner is provided with a first air extraction hole, which communicates with the groove ring;

[0021] The first sleeve and the second sleeve are both axially provided with a second air extraction hole, which communicates with the first air extraction hole;

[0022] The rotary rigid grinding device and the rotary flexible grinding device are both provided with an air extraction pump, which communicates with the second air extraction hole;

[0023] The shaft spiral piece assembly and the shaft cloth wheel rotating assembly are both provided with an upper spiral shaft, a lower spiral shaft, a top sealing piece and a bottom sealing piece;

[0024] The upper spiral shaft and the lower spiral shaft are coaxial, and the top of the lower spiral shaft is threadedly connected with the bottom of the upper spiral shaft;

[0025] The top sealing piece and the bottom sealing piece are respectively fixedly connected with the two ends of the lower spiral shaft, and both of them are perpendicular to the axis of the lower spiral shaft, and the distance between the top sealing piece and the bottom sealing piece is equal to the length of the nickel-titanium alloy rough pipe to be polished;

[0026] Both the top sealing piece and the bottom sealing piece are circular and have equal radii, the top sealing piece is composed of two semicircular plates which are detachably assembled on the lower spiral shaft;

[0027] The top end of the lower spiral shaft extends out of the top sealing piece, and the bottom end of the lower spiral shaft extends out of the bottom sealing piece.

[0028] In one of the embodiments, the shaft spiral piece assembly is further provided with a spiral piece sleeved on the lower spiral shaft and a plurality of fastening rods, the top of the spiral piece is fixedly connected with the bottom of the top sealing piece, and the bottom of the spiral piece is fixedly connected with the top of the bottom sealing piece;

[0029] The maximum axial radius of the spiral piece is smaller than the radius of the top sealing piece;

[0030] The middle of each fastening rod is fixedly connected with the lower spiral shaft, and both ends of each fastening rod are fixedly connected with the spiral piece;

[0031] The rotary rigid grinding device is also provided with a first rotary motor member and a first grinding auxiliary member, the first rotary motor member is arranged above the first grinding auxiliary member, the first rotary motor member is fixedly connected with the upper lifting block, the first grinding auxiliary member is fixedly connected with the lower lifting block, the rotation axis of the rotary motor member coincides with the axis of the shaft helical blade assembly, and the upper helical shaft of the shaft helical blade assembly is fixedly connected with the first rotary motor member;

[0032] The first grinding auxiliary member comprises an auxiliary sleeve, an isolation pipe, a first sealing ring and a second sealing ring, and the auxiliary sleeve abuts against the top of the first sleeve;

[0033] The auxiliary sleeve is sleeved outside the isolation pipe, the first sealing ring and the second sealing ring are arranged at the upper end and the lower end of the auxiliary sleeve respectively, the first sealing ring and the second sealing ring are fixedly connected with the inner wall of the auxiliary sleeve, and the upper end and the lower end of the isolation pipe abut against the first sealing ring and the second sealing ring respectively;

[0034] The top of the upper inner liner of the first inner liner abuts against the bottom of the second sealing ring.

[0035] In one of the embodiments, the bottom inner side of the first sleeve is provided with a first rotary hole, and the bottom end of the lower helical shaft of the shaft helical blade assembly is inserted into the first rotary hole;

[0036] The shaft radius of the circular groove of the rotary rigid grinding device is equal to the shaft radius of the first sleeve, the bottom outer side of the first sleeve is provided with two installation grooves which can be matched with two installation keys respectively, the installation keys are embedded into the installation grooves, and the first sleeve is inserted into the circular groove.

[0037] In one of the embodiments, the shaft cloth wheel rotating assembly is also provided with a cloth wheel which is sleeved on the lower helical shaft, and the shaft radius of the cloth wheel is equal to the radius of the top sealing piece;

[0038] The top of the cloth wheel abuts against the bottom of the top sealing piece, and the bottom abuts against the top of the bottom sealing piece.

[0039] In one of the embodiments, the shaft cloth wheel rotating assembly is also provided with a second rotary motor member and a second grinding auxiliary member, the second rotary motor member is arranged above the second grinding auxiliary member, the second rotary motor member is fixedly connected with the upper lifting block, the second grinding auxiliary member is fixedly connected with the lower lifting block, the rotation axis of the rotary motor member coincides with the axis of the shaft cloth wheel rotating assembly, and the upper helical shaft of the shaft cloth wheel rotating assembly is fixedly connected with the second rotary motor member;

[0040] The second grinding auxiliary member is cylindrical, the inner diameter is equal to the inner diameter of the inner liner, and the outer diameter is equal to the outer diameter of the second sleeve;

[0041] The bottom of the second rotary motor component is provided with a circular protrusion, and the top of the second grinding auxiliary component is provided with a cylindrical assembly cavity with a radius equal to that of the circular protrusion, and the circular protrusion is assembled in the assembly cavity;

[0042] The bottom of the second grinding auxiliary component abuts against the top of the second sleeve;

[0043] The bottom of the second sleeve is provided with a second rotary hole in the center of the inner side, and the bottom end of the lower helical shaft of the shaft rotating assembly is inserted into the second rotary hole;

[0044] The shaft radius of the circular groove of the rotary flexible grinding device is equal to the shaft radius of the second sleeve, the bottom of the second sleeve is provided with two installation grooves which can be matched with the two installation keys respectively, and the second sleeve is inserted into the circular groove;

[0045] The second sleeve is provided with a support ring inside, the outer wall of the support ring is fixedly connected with the inner wall of the second sleeve, the inner diameter of the support ring is equal to the inner diameter of the nickel-titanium alloy rough pipe to be polished, and the distance from the bottom of the support ring to the inner side of the bottom of the second sleeve is greater than the height of the second inner liner;

[0046] The top of the second inner liner abuts against the bottom of the second grinding auxiliary component, and the bottom abuts against the top of the support ring.

[0047] The beneficial effects of the present application are that the present application realizes automatic polishing by combining the rough polishing mode of the rotary rigid grinding device and the fine polishing mode of the rotary flexible grinding device, can effectively remove the inner wall defects of the nickel-titanium alloy rough pipe, reduce the surface roughness of the inner wall, and improve the smoothness and polishing efficiency. In addition, in the polishing process of the rotary rigid grinding device and the rotary flexible grinding device of the present application, the nickel-titanium alloy rough pipe can be closely attached to the first inner liner or the second inner liner, so that damage to the outer wall of the pipe during polishing can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 The flowchart of the inner wall polishing method of the nickel-titanium alloy rough pipe provided in the embodiment of the present application is shown;

[0049] Figure 2 The overall structure diagram of the rotary rigid grinding device provided in the embodiment of the present application is shown;

[0050] Figure 3 One of the cross-sectional structure diagrams of the rotary rigid grinding device provided in the embodiment of the present application along the first sleeve axis is shown;

[0051] Figure 4 The overall structure diagram of the rotary flexible grinding device provided in the embodiment of the present application is shown;

[0052] Figure 5Figure 1 is a schematic view of a cross-sectional structure along a first sleeve axis of a rotary flexible grinding device according to an embodiment of the present application;

[0053] Figure 6 Figure 2 is a schematic view of a structure of a lifting mechanism according to an embodiment of the present application;

[0054] Figure 7 Figure 3 is a schematic view of a structure of a first inner liner or a second inner liner according to an embodiment of the present application;

[0055] Figure 8 Figure 4 is a schematic view of a cross-sectional structure along an axial plane of the first inner liner or the second inner liner according to an embodiment of the present application;

[0056] Figure 9 Figure 5 is a schematic view of a structure of a shaft spiral fin assembly according to an embodiment of the present application;

[0057] Figure 10 Figure 6 is a schematic view of a structure of a shaft cloth wheel rotating assembly according to an embodiment of the present application;

[0058] Figure 11 Figure 7 is a schematic view of a structure of a first sleeve according to an embodiment of the present application;

[0059] Figure 12 Figure 8 is another schematic view of a structure of the first sleeve according to an embodiment of the present application.

[0060] Figure 1 is a schematic view of a cross-sectional structure along a first sleeve axis of a rotary flexible grinding device according to an embodiment of the present application; DETAILED DESCRIPTION

[0061] In order to make the purpose, technical scheme and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0062] It should be noted that in the description of the present application, "upper", "lower", "top", "bottom", orientation or positional relationship is based on the drawings and should be understood as these orientation terms are only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application. Figure 1

[0063] In one embodiment, as shown in the drawings, a method for polishing the inner wall of a nickel-titanium alloy rough pipe includes the following steps: Figure 1

[0064] S101, ultrasonic decontamination cleaning and drying of the nickel-titanium alloy rough pipe to be polished.

[0065] Ultrasonic cleaning is to use an aqueous oil stain remover as a cleaning medium for cleaning, which can remove oil stains, impurities, etc. on the inner and outer surfaces of the pipe, facilitating subsequent polishing treatment.

[0066] Specifically, the oil stain remover is a commercially available cleaner, and the mixing ratio of the cleaner and water is according to the usage instructions of the cleaner; the ultrasonic cleaning temperature is 50-80℃, and the cleaning time is 5-10 minutes; the drying temperature after cleaning is 70-85℃, and the drying time is 5-10 minutes; the drying machine is a commercially available box-type drying machine.

[0067] S102, placing the dried nickel-titanium alloy rough pipe to be polished into a rotary rigid grinding device, filling the nickel-titanium alloy rough pipe to be polished with coarse-grained grinding medium and water, and starting the rotary rigid grinding device to perform rough polishing on the nickel-titanium alloy rough pipe to be polished.

[0068] Specifically, the coarse-grained grinding medium is quartz sand with a particle size of 400-1200 mesh. The rotary rigid grinding device is combined with the coarse-grained grinding medium to drive the coarse-grained grinding medium to polish the inner wall of the nickel-titanium alloy rough pipe to be polished during rotary grinding, which can remove obvious machining marks on the pipe.

[0069] S103, placing the nickel-titanium alloy rough pipe after rough polishing into a rotary flexible grinding device, and starting the rotary flexible grinding device to use polishing liquid to perform fine polishing on the nickel-titanium alloy rough pipe to be polished.

[0070] ​​The polishing liquid is prepared by mixing chromium oxide polishing powder, aluminum oxide polishing powder and water in a mass ratio of 1:1:5-10, and the particle size of the chromium oxide polishing powder and the aluminum oxide polishing powder is 10-40 microns.

[0071] The chromium oxide polishing powder and the aluminum oxide polishing powder in the polishing liquid are fine abrasive grains, the rotary flexible grinding device does not cause damage to the pipe wall, and the rotary flexible grinding device and the polishing liquid can be combined to achieve high-precision polishing of the inner hole surface of the pipe.

[0072] S104, the nickel-titanium alloy rough pipe after fine polishing is ultrasonically cleaned and dried. The effect of ultrasonic water cleaning is to remove the polishing liquid, and after cleaning, the nickel-titanium alloy rough pipe with a high smooth inner wall surface is obtained.

[0073] As shown in Figure 2 and Figure 3 , the rotary rigid grinding device is provided with a cylindrical first inner liner 100 which can be tightly sleeved outside the nickel-titanium alloy rough pipe to be polished, a first sleeve 110 which is closed at the bottom, and an axial helical blade assembly 120 which can rotate around the axis of the first sleeve 110. The first sleeve 110 is sleeved outside the first inner liner 100, the axial helical blade assembly 120 is arranged inside the first inner liner 100, the axis of the axial helical blade assembly 120 coincides with the axis of the first sleeve 110, there is a gap between the axial helical blade assembly 120 and the inner wall of the nickel-titanium alloy rough pipe to be polished in the horizontal direction, and the width of the gap is greater than the thickness of the pipe wall of the nickel-titanium alloy rough pipe to be polished.

[0074] The axis of the axial helical blade assembly 120 coincides with the axis of the first sleeve 110, and the first sleeve 110 is sleeved outside the first inner liner 100, so that the axial helical blade assembly 120 can rotate along the axis inside the first inner liner 100. The width of the gap is greater than the thickness of the pipe wall of the nickel-titanium alloy rough pipe to be polished, which can ensure that the axial helical blade assembly 120 will not scratch the nickel-titanium alloy rough pipe during rotation.

[0075] As shown in Figure 4 and Figure 5 , the rotary flexible grinding device is provided with a cylindrical second inner liner 200 which can be tightly sleeved outside the nickel-titanium alloy rough pipe to be polished, a second sleeve 210 which is closed at the bottom, and an axial cloth wheel rotating assembly 220 which can rotate around the axis of the second sleeve 210. The second sleeve 210 is sleeved outside the second inner liner 200, the axial cloth wheel rotating assembly 220 is arranged inside the second sleeve 210, the axis of the axial cloth wheel rotating assembly 220 coincides with the axis of the second sleeve 210, and the maximum rotating diameter of the axial cloth wheel rotating assembly 220 is equal to the inner diameter of the nickel-titanium alloy rough pipe to be polished.

[0076] The shaft cloth wheel rotating assembly 220 can rotate in the second inner liner 200, the polishing liquid contains smaller polishing particles, and the shaft cloth wheel rotating assembly 220 and the polishing liquid can further polish the inner wall of the nickel-titanium alloy thick tube, thereby improving the surface finish of the inner wall.

[0077] In the embodiment, the automatic polishing is realized by combining the rough polishing mode of the rotary rigid grinding device and the fine polishing mode of the rotary flexible grinding device, the inner wall defects of the nickel-titanium alloy thick tube can be effectively removed, the surface roughness of the inner wall is reduced, and the polishing efficiency is improved. The first inner liner 100 and the second inner liner 200 can be tightly sleeved outside the nickel-titanium alloy thick tube to be polished, so that damage to the outer wall of the tube during polishing can be avoided.

[0078] In one embodiment, as shown in Figure 6 The rotary rigid grinding device and the rotary flexible grinding device are both provided with a lifting mechanism 300, the lifting mechanism 300 is provided with an upper base plate 310, a plurality of support columns 320, a lower base plate 330, a guide rail 340, an upper lifting block 350, and a lower lifting block 360.

[0079] The upper base plate 310 and the lower base plate 330 are parallel and vertically fixedly connected to the upper and lower ends of the plurality of support columns 320, and the guide rail 340 is vertically fixed to the middle of the upper base plate 310 and the lower base plate 330. The upper lifting block 350 and the lower lifting block 360 are both sleeved on the guide rail 340 and can slide up and down along the guide rail 340. The lower base plate 330 is provided with a circular groove 370 at the top, and two mounting keys 380 are horizontally arranged inside the circular groove 370. The depth of the circular groove 370 is half the thickness of the lower base plate 330.

[0080] Specifically, the upper base plate 310 and the lower base plate 330 of the lifting mechanism 300 in the embodiment are both rectangular metal plates and are horizontally arranged; the lifting mechanism 300 has four support columns 320, which are respectively connected at the four corners of the upper base plate 310 and the lower base plate 330, and the four support columns 320 are perpendicular to the upper base plate 310 and the lower base plate 330. The guide rail 340 is two slide columns, each of which is arranged in the middle of two support columns 320, and the slide columns are perpendicular to the upper base plate 310 and the lower base plate 330. The upper lifting block 350 and the lower lifting block 360 each include a fixed ring and two fixed ears on both sides of the fixed ring, which are respectively sleeved with two slide columns. The upper lifting block 350 and the lower lifting block 360 can slide up and down along the guide rail 340.

[0081] In the embodiment, the lower lifting block 360 and the upper lifting block 350 can move up and down at a certain speed under the control of a motor, and the specific type and structure of the motor are not limited.

[0082] In one embodiment, as shown in Figure 7 and Figure 8As shown, the heights of the first inner liner 100 and the second inner liner 200 are equal to the length of the nickel-titanium alloy rough pipe to be polished, and the first inner liner 100 and the second inner liner 200 each include an upper inner liner 400 and a lower inner liner 410, the upper inner liner 400 is fixedly connected to the top of the lower inner liner 410, and the height ratio of the upper inner liner 400 to the lower inner liner 410 is 1:16-19.

[0083] In this embodiment, the height ratio of the upper inner liner 400 to the lower inner liner 410 is specifically 1:19. The first inner liner 100 and the second inner liner 200 are each made of an acid-resistant high polymer material.

[0084] The middle part of the side wall of the lower inner liner 410 is uniformly provided with a plurality of first through holes 420, each of which vertically penetrates the side wall of the lower inner liner 410, and the side wall of the lower inner liner 410 is provided with a plurality of groups of second through holes 430 in the radial direction, the number of which is equal to that of the first through holes 420, each group of second through holes 430 includes a plurality of second through holes 430 uniformly distributed in the vertical direction, each of which radially penetrates the side wall of the lower inner liner 410, and each first through hole 420 communicates with all the second through holes 430 in a group of second through holes 430.

[0085] Specifically, the diameters of the first through holes 420 and the second through holes 430 are each 0.5-5 mm.

[0086] The bottom of the upper inner liner 400 is provided with a groove ring 440, and each first through hole 420 communicates with the groove ring 440; the side wall of the upper inner liner 400 is provided with a first air extraction hole 450, which communicates with the groove ring 440. The first sleeve 110 and the second sleeve 210 are each axially provided with a second air extraction hole 460, which communicates with the first air extraction hole 450; the rotary rigid grinding device and the rotary flexible grinding device are each provided with an air extraction pump, which communicates with the second air extraction hole 460.

[0087] In this embodiment, the first through holes 420, the second through holes 430, the groove ring 440, the first air extraction hole 450, the second air extraction hole 460, and the air extraction pump are all in communication, forming an air extraction channel, so that when the air extraction pump is turned on, the nickel-titanium alloy rough pipe can be tightly attached to the inner wall surface of the first inner liner 100 or the second inner liner 200, and damage to the outer wall of the pipe during polishing can be avoided.

[0088] In one of the embodiments, as shown in Figure 9 and Figure 10 The shaft helical fin assembly 120 and the shaft cloth wheel rotating assembly 220 are each provided with an upper helical shaft 500, a lower helical shaft 510, a top blocking fin 520, and a bottom blocking fin 530. The upper helical shaft 500 is coaxial with the lower helical shaft 510, and the top of the lower helical shaft 510 is threadedly connected to the bottom of the upper helical shaft 500.

[0089] The top sealing sheet 520 and the bottom sealing sheet 530 are fixedly connected with two ends of the lower helical shaft 510 respectively, the top sealing sheet 520 and the bottom sealing sheet 530 are perpendicular to the axis of the lower helical shaft 510, and the distance between the top sealing sheet 520 and the bottom sealing sheet 530 is equal to the length of the nickel-titanium alloy rough pipe to be polished;

[0090] The top sealing sheet 520 and the bottom sealing sheet 530 are both circular and have equal radii, so that the top sealing sheet 520 and the bottom sealing sheet 530 can seal the space between the first inner liner 100 or the second inner liner 200 during polishing, avoiding the spilling of the grinding medium or the polishing liquid. The top sealing sheet 520 is composed of two semicircular plates, which can be detachably assembled on the lower helical shaft 510. The top sealing sheet 520 is composed of two semicircular plates, which facilitates the disassembly and assembly of the top sealing sheet 520.

[0091] In this embodiment, the shaft helical fin assembly 120 and the shaft cloth wheel rotating assembly 220 are also provided with fasteners for fixing the two semicircular plates, which are fastened after the two semicircular plates are assembled on the lower helical shaft 510.

[0092] The top end of the lower helical shaft 510 penetrates the top sealing sheet 520 and extends out, and the bottom end of the lower helical shaft 510 penetrates the bottom sealing sheet 530 and extends out. The top end of the lower helical shaft 510 extends out to be connected with the upper helical shaft 500, and the bottom end of the lower helical shaft 510 extends out to be connected with the lifting mechanism 300.

[0093] In one embodiment, the shaft helical fin assembly 120 is also provided with a helical fin 540 sleeved on the lower helical shaft 510 and a plurality of fastening rods 550. The top of the helical fin 540 is fixedly connected with the bottom of the top sealing sheet 520, and the bottom of the helical fin 540 is fixedly connected with the top of the bottom sealing sheet 530. The maximum axial radius of the helical fin 540 is smaller than the radius of the top sealing sheet 520. The middle of each fastening rod 550 is fixedly connected with the lower helical shaft 510, and both ends of each fastening rod 550 are fixedly connected with the helical fin 540.

[0094] The function of the fastening rod 550 is to fix the helical fin 540 with the lower helical shaft 510.

[0095] In one of the embodiments, the rotary rigid grinding device is further provided with a first rotary motor member 130 and a first grinding auxiliary member 140, the first rotary motor member 130 is arranged above the first grinding auxiliary member 140, the first rotary motor member 130 is fixedly connected with the upper lifting block 350, the first grinding auxiliary member 140 is fixedly connected with the lower lifting block 360, the rotation axis of the rotary motor member coincides with the axis of the shaft helical blade assembly 120, the upper helical shaft 500 of the shaft helical blade assembly 120 is fixedly connected with the first rotary motor member 130. The first rotary motor member 130 can drive the upper helical shaft 500 of the rotary rigid grinding device to rotate.

[0096] The first grinding auxiliary member 140 comprises an auxiliary sleeve 141, an isolation pipe 142, a first sealing ring 143 and a second sealing ring 144, and the auxiliary sleeve 141 abuts against the top of the first sleeve 110. The auxiliary sleeve 141 prevents the coarse-grained grinding medium from spilling out when the shaft helical blade assembly 120 rotates.

[0097] The auxiliary sleeve 141 is sleeved outside the isolation pipe 142, the first sealing ring 143 and the second sealing ring 144 are arranged at the upper and lower ends of the auxiliary sleeve 141 respectively, the first sealing ring 143 and the second sealing ring 144 are fixedly connected with the inner wall of the auxiliary sleeve 141, the upper and lower ends of the isolation pipe 142 abut against the first sealing ring 143 and the second sealing ring 144 respectively; the top of the upper inner liner 400 of the first inner liner 100 abuts against the bottom of the second sealing ring 144. The first sealing ring 143 and the second sealing ring 144 are used to install the isolation pipe 142, the isolation pipe 142 is made of wear-resistant material, which can prevent the coarse-grained grinding medium from damaging the auxiliary sleeve 141.

[0098] The rotary motor can be arranged inside the first rotary motor member 130 to drive the upper helical shaft 500 to rotate.

[0099] In one of the embodiments, as shown in Figure 11 and Figure 12 The bottom inside center of the first sleeve 110 is provided with a first rotary hole 111, and the bottom end of the lower helical shaft 510 of the shaft helical blade assembly 120 is inserted into the first rotary hole 111.

[0100] The shaft radius of the circular groove 370 of the rotary rigid grinding device is equal to the shaft radius of the first sleeve 110, the bottom outside of the first sleeve 110 is provided with two installation grooves 112 which can be matched with two installation keys 380 respectively, the installation keys 380 are embedded into the installation grooves 112, and the first sleeve 110 is inserted into the circular groove 370.

[0101] The installation keys 380 and the installation grooves 112 can prevent the first sleeve 110 from rotating relative to the lower base plate 330.

[0102] In one embodiment, the shaft cloth wheel rotating assembly 220 is further provided with a cloth wheel 560 sleeved on the lower helical shaft 510, the shaft radius of the cloth wheel 560 is equal to the radius of the top blocking piece 520; the top of the cloth wheel 560 is in abutment with the bottom of the top blocking piece 520, and the bottom is in abutment with the top of the bottom blocking piece 530. The top blocking piece 520 of the shaft cloth wheel rotating assembly 220 is further provided with a fastening bolt sleeved on the lower helical shaft 510.

[0103] The cloth wheel 560 is a core sponge / cloth grinding wheel, the core is a through-hole metal structure, and the cloth wheel 560 can adsorb polishing liquid.

[0104] In one embodiment, the shaft cloth wheel rotating assembly 220 is further provided with a second rotating motor member 230 and a second grinding auxiliary member 240, the second rotating motor member 230 is arranged above the second grinding auxiliary member 240, the second rotating motor member 230 is fixedly connected with the upper lifting block 350, the second grinding auxiliary member 240 is fixedly connected with the lower lifting block 360, the rotation axis of the rotating motor member coincides with the axis of the shaft cloth wheel rotating assembly 220, and the upper helical shaft 500 of the shaft cloth wheel rotating assembly 220 is fixedly connected with the second rotating motor member 230.

[0105] The second grinding auxiliary member 240 is cylindrical, the inner diameter is equal to the inner diameter of the inner liner, and the outer diameter is equal to the outer diameter of the second sleeve 210; the bottom of the second rotating motor member 230 is provided with a circular protrusion, the top of the second grinding auxiliary member 240 is provided with a cylindrical assembly cavity with a radius equal to that of the circular protrusion, and the circular protrusion is assembled in the assembly cavity. The second grinding auxiliary member 240 and the second rotating motor member 230 are sealingly assembled through the circular protrusion and the assembly cavity, so that the polishing liquid can be prevented from spilling out.

[0106] The bottom of the second grinding auxiliary member 240 is in abutment with the top of the second sleeve 210; the bottom inner side of the second sleeve 210 is provided with a second rotating hole, and the bottom end of the lower helical shaft 510 of the shaft cloth wheel rotating assembly 220 is inserted into the second rotating hole; the shaft radius of the circular groove 370 of the rotating flexible grinding device is equal to the shaft radius of the second sleeve 210, the bottom outer side of the second sleeve 210 is provided with two installation grooves 112 which can be respectively matched with two installation keys 380, and the second sleeve 210 is inserted into the circular groove 370; the second sleeve 210 is internally provided with a support ring 211, the outer wall of the support ring 211 is fixedly connected with the inner wall of the second sleeve 210, the inner diameter of the support ring 211 is equal to the inner diameter of the nickel-titanium alloy rough pipe to be polished, and the distance from the bottom of the support ring 211 to the bottom inner side of the second sleeve 210 is greater than the height of the second inner liner 200; the top of the second inner liner 200 is in abutment with the bottom of the second grinding auxiliary member 240, and the bottom is in abutment with the top of the support ring 211.

[0107] The position relationship between the second rotating hole and the two mounting keys 380 at the bottom of the second sleeve 210 is the same as the position relationship between the first rotating hole 111 and the two mounting slots 112 at the bottom of the first sleeve 110.

[0108] Specifically, the space below the inner support ring 211 of the second sleeve 210 is used to store the polishing liquid. The rotation of the helical blade 540 and the cloth wheel 560 can be controlled by the first rotating motor member 130 and the second rotating motor member 230, respectively.

[0109] In a specific embodiment, the inner wall polishing method of a nickel-titanium alloy rough pipe with a polishing inner diameter of 20 mm, an outer diameter of 21 mm, and a pipe length of 1000 mm is described. The inner wall polishing method of the nickel-titanium alloy rough pipe in this embodiment includes the following steps:

[0110] (1) Place the nickel-titanium alloy rough pipe to be polished in an ultrasonic cleaning tank, mix the oil removal cleaner with water according to the usage instructions, and raise the water temperature to 65°C. Clean for 8 minutes to remove oil, dirt, and impurities on the inner and outer surfaces of the pipe. After cleaning, place the pipe in an 80°C oven and dry for 8 minutes.

[0111] (2) Move the upper lifting block 350 and the lower lifting block 360 of the rotating rigid grinding device, and lift the first rotating motor member 130 and the first grinding auxiliary member 140 upwards until the shaft helical blade assembly 120 is located in the middle of the first grinding auxiliary member 140, and the distance between the first grinding auxiliary member 140 and the first sleeve 110 is greater than 1000 mm;

[0112] Place the dried nickel-titanium alloy rough pipe to be polished into the first inner liner 100, start the air pump, and ensure that the nickel-titanium alloy rough pipe to be polished is adsorbed to the inner wall of the first inner liner 100;

[0113] Move the lower lifting block 360 until the distance between the first grinding auxiliary member 140 and the first sleeve 110 is 150 mm;

[0114] Move the upper lifting block 350 until the bottom end of the lower helical shaft 510 of the shaft helical blade assembly 120 is inserted into the first rotating hole 111;

[0115] Remove the top blocking plate of the shaft helical blade assembly 120;

[0116] Start the first rotating motor member 130 and control the rotation speed of the helical blade 540 to be 15 revolutions per minute;

[0117] Through the 150 mm gap between the first grinding auxiliary member 140 and the first sleeve 110, add water and 800 mesh quartz sand to the nickel-titanium alloy rough pipe to be polished at the same time until the nickel-titanium alloy rough pipe is filled;

[0118] Close the first rotating motor 130, install the top blocking piece 520 of the shaft spiral piece assembly 120;

[0119] Move the lower lifting block 360 until the first grinding auxiliary member 140 abuts against the first sleeve 110;

[0120] Start the rotation of the first rotating motor 130, control the speed to be 150 rpm, and continue to work for 5 minutes;

[0121] Adjust the rotation speed of the first rotating motor 130 to 15 rpm, move the upper lifting block 350 until the shaft spiral piece assembly 120 moves into the first grinding auxiliary member 140, and close the first rotating motor 130;

[0122] Move the lower lifting block 360 until the first grinding auxiliary member 140 moves to a distance greater than 1000 mm from the top surface of the first sleeve 110;

[0123] Take out the rough nickel-titanium alloy pipe to be polished.

[0124] (3) Move the upper lifting block 350 and the lower lifting block 360 of the rotating flexible grinding device, and lift the second rotating motor 230 and the second grinding auxiliary member 240 upwards until the cloth wheel 560 is flush with the second grinding auxiliary member 240, and the distance between the second grinding auxiliary member 240 and the second sleeve 210 is greater than 1000 mm;

[0125] Fill the polishing liquid with a volume of V inside the second sleeve 210, V = π × (R1 2 -R2 2 ) × (H1+H2), where R1 is the outer radius of the lower liner 410, R2 is the inner hole radius of the lower liner 410, H1 is the height of the lower liner 410, and H2 is the height of the upper liner 400.

[0126] Place the rough polished nickel-titanium alloy pipe in step (2) into the second liner 200, start the air pump, and ensure that the nickel-titanium alloy pipe to be polished is adsorbed to the inner wall of the second liner 200;

[0127] Move the upper lifting block 350 and the lower lifting block 360 until the bottom end of the lower spiral shaft 510 of the shaft cloth wheel rotating assembly 220 is inserted into the second rotating hole, and the bottom of the second grinding auxiliary member contacts the top end of the second sleeve 210. At this time, the cloth wheel 560 is completely immersed in the polishing liquid;

[0128] Start the second rotating motor 230, control the rotation speed of the spiral piece 540 to be 15 rpm, and continue to rotate for 3 minutes to make the cloth wheel 560 completely absorb the polishing liquid;

[0129] The lifting block 350 is moved until the bottom end of the cloth wheel 560 is flush with the bottom end of the second inner liner 200;

[0130] The rotation speed of the second rotary motor member 230 is adjusted to 150 rpm, and the rotation is continued for 5 minutes; the rotation speed of the second rotary motor member 130 is adjusted to 15 rpm, the lifting block 350 is moved, and after the bottom end of the cloth wheel 560 is flush with the bottom end of the second grinding auxiliary member 240, the lifting block 360 is moved until the distance between the cloth wheel 560 and the second grinding auxiliary member 240 away from the second sleeve 210 is greater than 1000 mm;

[0131] The nickel-titanium alloy rough pipe is taken out.

[0132] (4) The nickel-titanium alloy rough pipe is placed in an ultrasonic cleaning tank, cleaned with clean water at 70°C, and the cleaning time is 8 minutes; after cleaning, drying is performed, the drying temperature is 80°C, and the drying time is 8 minutes, the polishing agent attached to the inner surface of the pipe is removed, and finally the nickel-titanium alloy pipe with a high smooth inner wall surface is obtained.

[0133] The nickel-titanium alloy rough pipe inner wall polishing method of the embodiment combines the rough polishing method of the rotary rigid grinding device and the fine polishing method of the rotary flexible grinding device to realize automatic polishing, which can effectively remove the inner wall defects of the nickel-titanium alloy rough pipe, reduce the inner wall surface roughness, and improve the smoothness and polishing efficiency.

[0134] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the patent of the present application. It should be noted that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for polishing the inner wall of a nickel-titanium alloy coarse tube, characterized in that, Includes the following steps: The nickel-titanium alloy rough tube to be polished is ultrasonically cleaned and then dried. The dried nickel-titanium alloy coarse tube to be polished is placed into a rotary rigid grinding device, and coarse-grained grinding media and water are filled inside the nickel-titanium alloy coarse tube to be polished. The rotary rigid grinding device is then started to perform coarse polishing on the nickel-titanium alloy coarse tube to be polished. The coarse nickel-titanium alloy tube after rough polishing is placed into a rotary flexible grinding device, and the rotary flexible grinding device is started to use polishing liquid to fine polish the nickel-titanium alloy tube to be polished. The finely polished nickel-titanium alloy coarse tube is ultrasonically water-cleaned and then dried. The rotary rigid grinding device is provided with a cylindrical first inner liner (100) that can be tightly fitted to the outside of the nickel-titanium alloy coarse tube to be polished, a first sleeve (110) with a closed bottom, and a shaft spiral blade assembly (120) that can rotate around the axis of the first sleeve (110). The first sleeve (110) is fitted to the outside of the first inner liner (100), and the shaft spiral blade assembly (120) is disposed inside the first inner liner (100). The axis of the shaft spiral blade assembly (120) coincides with the axis of the first sleeve (110). There is a horizontal gap between the shaft spiral blade assembly (120) and the inner wall of the nickel-titanium alloy coarse tube to be polished. The width of the gap is greater than the wall thickness of the nickel-titanium alloy coarse tube to be polished. The rotary flexible grinding device is provided with a cylindrical second inner liner (200) that can be tightly fitted onto the outside of the nickel-titanium alloy coarse tube to be polished, a bottom-closed second sleeve (210), and a shaft-cloth wheel rotating assembly (220) that can rotate around the axis of the second sleeve (210). The second sleeve (210) is fitted onto the outside of the second inner liner (200), and the shaft-cloth wheel rotating assembly (220) is disposed inside the second sleeve (210). The axis of the shaft-cloth wheel rotating assembly (220) coincides with the axis of the second sleeve (210), and the maximum rotation diameter of the shaft-cloth wheel rotating assembly (220) is equal to the inner diameter of the nickel-titanium alloy coarse tube to be polished.

2. The method for polishing the inner wall of a nickel-titanium alloy coarse tube according to claim 1, characterized in that, The coarse-grained grinding media is quartz sand with a particle size of 400~1200 mesh. The polishing liquid is prepared by mixing chromium oxide polishing powder, aluminum oxide polishing powder and water in a mass ratio of 1:1:5~10. The particle size of both chromium oxide polishing powder and aluminum oxide polishing powder is 10~40μm.

3. The method for polishing the inner wall of a nickel-titanium alloy coarse tube according to claim 1, characterized in that, Both the rotary rigid grinding device and the rotary flexible grinding device are equipped with a lifting mechanism (300). The lifting mechanism (300) is equipped with an upper base plate (310), multiple supporting columns (320), a lower base plate (330), a guide rail (340), an upper lifting block (350), and a lower lifting block (360). The upper substrate (310) and the lower substrate (330) are parallel and aligned vertically and fixedly connected to the upper and lower ends of the plurality of support columns (320), and the guide rail (340) is vertically fixed between the upper substrate (310) and the lower substrate (330). The upper lifting block (350) and the lower lifting block (360) are both sleeved on the guide rail (340) and can slide up and down along the guide rail (340); The bottom substrate (330) has a circular groove (370) on its top, and two mounting keys (380) are horizontally arranged inside the circular groove (370).

4. The method for polishing the inner wall of a nickel-titanium alloy coarse tube according to claim 3, characterized in that, The height of the first inner liner (100) and the second inner liner (200) is equal to the length of the nickel-titanium alloy coarse tube to be polished. The first inner liner (100) and the second inner liner (200) each include an upper inner liner (400) and a lower inner liner (410). The upper inner liner (400) is fixedly connected to the top of the lower inner liner (410). The height ratio of the upper inner liner (400) to the lower inner liner (410) is 1:16~19. The lower liner (410) has a plurality of first through holes (420) uniformly arranged along the axial direction in the middle of the side wall. Each first through hole (420) vertically penetrates the side wall of the lower liner (410). The side wall of the lower liner (410) has a plurality of sets of second through holes (430) in the radial direction, the number of which is equal to the number of first through holes (420). Each set of second through holes (430) includes a plurality of second through holes (430) uniformly distributed in the vertical direction. Each second through hole (430) radially penetrates the side wall of the lower liner (410). Each first through hole (420) is connected to all the second through holes (430) in a set of second through holes (430). The upper inner liner (400) has a grooved ring (440) in the middle of its bottom, and each first through hole (420) is connected to the grooved ring (440); The side wall of the upper liner (400) is provided with a first air extraction hole (450), which is connected to the groove ring (440). Both the first sleeve (110) and the second sleeve (210) are axially provided with a second air extraction hole (460), and the second air extraction hole (460) is connected to the first air extraction hole (450); Both the rotary rigid grinding device and the rotary flexible grinding device are equipped with an air pump, which is connected to the second air extraction port (460). Both the shaft spiral blade assembly (120) and the shaft cloth wheel rotating assembly (220) are provided with an upper spiral shaft (500), a lower spiral shaft (510), a top sealing plate (520), and a bottom sealing plate (530); The upper helical shaft (500) and the lower helical shaft (510) are coaxial, and the top of the lower helical shaft (510) is threadedly connected to the bottom of the upper helical shaft (500). The top sealing plate (520) and the bottom sealing plate (530) are fixedly connected to both ends of the lower spiral shaft (510), respectively. The top sealing plate (520) and the bottom sealing plate (530) are both perpendicular to the axis of the lower spiral shaft (510). The distance between the top sealing plate (520) and the bottom sealing plate (530) is equal to the length of the nickel-titanium alloy coarse tube to be polished. The top sealing plate (520) and the bottom sealing plate (530) are both circular and have the same radius. The top sealing plate (520) is composed of two semi-circular plates, which are detachably assembled to the lower spiral shaft (510). The top end of the lower spiral shaft (510) extends through the top sealing plate (520), and the bottom end of the lower spiral shaft (510) extends through the bottom sealing plate (530).

5. The method for polishing the inner wall of a nickel-titanium alloy coarse tube according to claim 4, characterized in that, The shaft spiral blade assembly (120) is further provided with a spiral blade (540) sleeved on the lower spiral shaft (510) and a plurality of fastening rods (550). The top of the spiral blade (540) is fixedly connected to the bottom of the top sealing plate (520), and the bottom of the spiral blade (540) is fixedly connected to the top of the bottom sealing plate (530). The maximum axial radius of the spiral blade (540) is smaller than the radius of the top sealing blade (520); The middle of each fastening rod (550) is fixedly connected to the lower spiral shaft (510), and both ends of each fastening rod (550) are fixedly connected to the spiral blade (540).

6. The method for polishing the inner wall of a nickel-titanium alloy coarse tube according to claim 5, characterized in that, The rotary rigid grinding device is further provided with a first rotary motor component (130) and a first grinding auxiliary component (140). The first rotary motor component (130) is disposed above the first grinding auxiliary component (140). The first rotary motor component (130) is fixedly connected to the upper lifting block (350), and the first grinding auxiliary component (140) is fixedly connected to the lower lifting block (360). The rotation axis of the rotary motor component coincides with the axis of the shaft spiral blade assembly (120). The upper spiral shaft (500) of the shaft spiral blade assembly (120) is fixedly connected to the first rotary motor component (130). The first grinding auxiliary component (140) includes an auxiliary sleeve (141), an isolation tube (142), a first sealing ring (143), and a second sealing ring (144), wherein the auxiliary sleeve (141) abuts against the top of the first sleeve (110); The auxiliary sleeve (141) is sleeved on the outside of the isolation tube (142). The first sealing ring (143) and the second sealing ring (144) are respectively disposed at the upper and lower ends of the auxiliary sleeve (141). The first sealing ring (143) and the second sealing ring (144) are both fixedly connected to the inner wall of the auxiliary sleeve (141). The upper and lower ends of the isolation tube (142) abut against the first sealing ring (143) and the second sealing ring (144) respectively. The top of the upper inner liner (400) of the first inner liner (100) and the bottom of the second sealing ring (144) abut against each other; The first sleeve (110) has a first rotating hole (111) at the center of its bottom inner side, and the bottom end of the lower spiral shaft (510) of the shaft spiral blade assembly (120) is inserted into the first rotating hole (111). The axial radius of the circular groove (370) of the rotary rigid grinding device is equal to that of the first sleeve (110). Two mounting slots (112) are provided on the outer bottom of the first sleeve (110) so as to be matched and installed with two mounting keys (380) respectively. The mounting keys (380) are embedded in the mounting slots (112), and the first sleeve (110) is inserted into the circular groove (370).

7. The method for polishing the inner wall of a nickel-titanium alloy coarse tube according to claim 4, characterized in that, The shaft cloth wheel rotating assembly (220) is also provided with a cloth wheel (560) sleeved on the lower spiral shaft (510), and the shaft radius of the cloth wheel (560) is equal to the radius of the top sealing plate (520); The top of the cloth wheel (560) abuts against the bottom of the top sealing plate (520), and the bottom abuts against the top of the bottom sealing plate (530).

8. The method for polishing the inner wall of a nickel-titanium alloy coarse tube according to claim 7, characterized in that, The shaft cloth wheel rotating assembly (220) is further provided with a second rotating motor component (230) and a second grinding auxiliary component (240). The second rotating motor component (230) is disposed above the second grinding auxiliary component (240). The second rotating motor component (230) is fixedly connected to the upper lifting block (350), and the second grinding auxiliary component (240) is fixedly connected to the lower lifting block (360). The rotation axis of the rotating motor component coincides with the axis of the shaft cloth wheel rotating assembly (220). The upper spiral shaft (500) of the shaft cloth wheel rotating assembly (220) is fixedly connected to the second rotating motor component (230). The second grinding auxiliary component (240) is cylindrical, with an inner diameter equal to the inner diameter of the liner and an outer diameter equal to the outer diameter of the second sleeve (210); The bottom of the second rotary motor component (230) is provided with a circular protrusion, and the top of the second grinding auxiliary component (240) is provided with a columnar assembly cavity with a radius equal to that of the circular protrusion, and the circular protrusion is assembled in the assembly cavity; The bottom of the second grinding auxiliary component (240) abuts against the top of the second sleeve (210); The second sleeve (210) has a second rotating hole at the center of its inner bottom side, and the bottom end of the lower spiral shaft (510) of the shaft cloth wheel rotating assembly (220) is inserted into the second rotating hole; The axial radius of the circular groove (370) of the rotary flexible grinding device is equal to that of the second sleeve (210). Two mounting slots (112) are provided on the outer bottom of the second sleeve (210) to be matched with two mounting keys (380) respectively. The second sleeve (210) is inserted into the circular groove (370). The second sleeve (210) is provided with a support ring (211) inside. The outer wall of the support ring (211) is fixedly connected to the inner wall of the second sleeve (210). The inner diameter of the support ring (211) is equal to the inner diameter of the nickel-titanium alloy tube to be polished. The distance from the bottom of the support ring (211) to the inner side of the bottom of the second sleeve (210) is greater than the height of the second liner (200). The top of the second liner (200) abuts against the bottom of the second grinding aid (240), and the bottom abuts against the top of the support ring (211).

Images