Inner cavity polishing device for valve machining

Abstract

The invention relates to the technical field of valve inner cavity machining, in particular to an inner cavity polishing device for valve machining, which comprises a workbench and a driving assembly on the workbench, the output end of the driving assembly is rotatably provided with a functional shaft, the end part of the functional shaft is fixedly provided with a first base body, and the top of the first base body extends outwards to form a lug body; the lug body corresponds to a sealing surface of an inner cavity of the valve, and a plurality of self-adaptive polishing heads are arranged on the lug body in a circumferential array mode; a plurality of oil feeding structures are further mounted on the lug body and located between the polishing heads, each oil feeding structure comprises a center oil cavity formed in the first base body, the center oil cavities and the first base body are coaxially designed, and an annular oil groove is formed in the portion, close to the outer edge, of the first base body; lubricating oil is accurately sprayed to a polishing area through rotating centrifugal force, meanwhile, the self-adaptive constant-pressure polishing head ensures that polishing stress is uniform, the surface precision is guaranteed, and the testing module can verify the polishing quality by testing the sealing performance.

Description

Technical Field

[0001] This invention relates to the technical field of valve internal cavity processing, specifically to an internal cavity polishing device for valve processing. Background Technology

[0002] In the field of intelligent manufacturing equipment, the manufacturing and maintenance of valves, especially gate valves, often require a final fine grinding of the valve seat inner cavity sealing surface due to the extremely high requirements for smoothness and geometric accuracy. Currently, the operation mostly relies on operators holding a flexible grinding rod and inserting it into the valve cavity, or using special tools to drive the grinding head to rotate and process, so that the inner cavity sealing surface meets the corresponding standards.

[0003] However, valves typically have small diameters and complex internal structures, creating a nearly enclosed and restricted working environment. This leads to a technical problem: during the grinding process, it is difficult to provide continuous and effective lubrication and cooling to the contact area between the grinding head and the sealing surface.

[0004] In existing technologies, common lubrication methods include manual dripping through external oil pipes or relying on the operator to apply lubricant in advance. The former is difficult to deliver lubricant accurately and evenly to the high-speed rotating grinding point due to obstructed vision and space, resulting in poor lubrication and significant waste. The latter suffers from short lubrication duration and the inability to continuously replenish lubricant during processing. Lack of effective lubrication directly leads to a series of adverse consequences: First, metal shavings and abrasive particles generated during grinding cannot be washed away in time, easily causing secondary scratches on the sealing surface. Second, the accumulation of frictional heat may lead to local annealing or thermal deformation of the workpiece, affecting the hardness and shape accuracy of the sealing surface. Third, under dry grinding conditions, the wear of the grinding head is accelerated, its lifespan is significantly shortened, and processing costs and tool replacement frequency are increased. Summary of the Invention

[0005] This invention provides an internal cavity polishing device for valve processing. It uses centrifugal force to precisely spray lubricating oil onto the polishing area. At the same time, the adaptive constant pressure polishing head ensures uniform polishing force and guarantees surface accuracy. The testing module can verify the polishing quality by testing the sealing performance.

[0006] To achieve the above objectives, the present invention provides the following technical solution: An internal cavity polishing device for valve processing, comprising: The worktable and its drive assembly have a functional shaft rotatably mounted at the output end of the drive assembly. A first base is fixedly mounted at the end of the functional shaft. An ear extends outward from the top of the first base, and the ear corresponds to the sealing surface of the valve cavity. Multiple adaptive grinding heads are arranged in a circumferential array on the ear. Multiple oil supply structures are also installed on the ear between the grinding heads. Each oil supply structure includes a central oil cavity inside the first base, which is coaxial with the first base. An annular oil groove is formed inside the first base near its outer edge, surrounding the central oil cavity. Multiple channels are also formed on the first base, with both ends of the channels communicating with the annular oil groove and the central oil cavity, respectively. Multiple micro-spray holes facing outward are formed through the inner wall of the annular oil groove.

[0007] Optionally, the adaptive polishing head includes a limiting rod that slides through the ear body. The top of the limiting rod is designed with a rod cap, and a pressure sensor is mounted on the lower surface of the rod cap. A constant force structure is fixedly installed between the pressure receiving surface of the pressure sensor and the top of the ear body. The constant force structure is used to provide a constant axial pressure to the limiting rod. A polishing disc is detachably installed at the bottom end of the limiting rod.

[0008] Optionally, after fine grinding, a test valve body is detachably installed at the bottom end of the limiting rod. The test valve body is used to simulate the valve disc inside the valve cavity. A second base is fixedly installed at the bottom of the test valve body. An airbag seat is fixedly installed on the circumferential outer wall of the second base near the bottom. An annular airbag is fixedly installed on the airbag seat. After gas is injected into the annular airbag, it can expand circumferentially. The outer wall of the annular airbag can abut against the cylindrical surface below the sealing surface of the valve cavity, so that a test space is formed between the annular airbag, the second base, the test valve body and the cylindrical surface. The annular airbag can be associated with an external positive pressure gas source. A reaction structure for monitoring the pressure change of the test space is also installed on the second base.

[0009] Optionally, the reaction structure includes a cavity formed inside the second substrate, the cavity being connected to an external negative pressure gas source, and the pipeline design not interfering with the normal operation of the test space. The inner wall of the cavity is provided with a gas channel connected to the test space, and a pressure sensor is fixedly installed on the outer wall of the second substrate within the test space.

[0010] Optionally, the slit is a straight channel designed along the radial line of the first substrate, and the micro-spray orifice is designed to be inclined downwards, with the micro-spray orifice facing the seat surface of the valve inner cavity sealing surface.

[0011] Optionally, the grinding disc has a fan-shaped annular structure, and the grinding disc is made of alloy steel with a Rockwell hardness value of 40 or higher, and a closed-cell polyurethane pad is attached to the grinding disc.

[0012] Optionally, the drive assembly includes a frame fixedly mounted on a workbench, an assembly frame slidably mounted on the frame, the sliding direction of the assembly frame being in the same direction as the axis of the first base, a servo motor and a rotating shaft sleeve fixedly mounted on the assembly frame, a rotating shaft inside the rotating shaft sleeve being fixedly connected to a functional shaft, and the output end of the servo motor being drively connected to the rotating shaft inside the rotating shaft sleeve through a reducer.

[0013] Optionally, the top of the workbench has an assembly plate for mounting fixtures that rotates, and a servo cylinder is fixedly mounted on the frame, with the output end of the servo cylinder fixedly connected to the top of the assembly frame.

[0014] This invention provides an internal cavity polishing device for valve processing, which has the following advantages compared to the prior art: 1. Through the cooperation between the first base, the central oil cavity, the narrow channel, the annular oil groove and the micro-spraying hole, the first base acts as a rotating carrier. Its internal coaxially designed central oil cavity forms the oil storage core. When the device is started, the first base rotates at high speed. The physical effect of centrifugal force is converted into the main power for conveying lubricating oil. Under the centrifugal action, the oil medium is forced from the low-pressure central oil cavity into the radially designed slender narrow channel. The high-pressure oil flow flows into the annular oil groove located at the maximum radius of the rotating body. Under the drive of extremely high pressure, the lubricating oil is delivered from the micro-spraying hole inclined downward on the wall of the annular oil groove to provide the oil medium for the grinding area of ​​the sealing surface flange.

[0015] Second, through the cooperation between the limiting rod, rod cap, pressure sensor and constant force structure, the limiting rod acts as the execution carrier, with the grinding disc at its bottom directly contacting the sealing surface, while the rod cap and pressure sensor at the top constitute monitoring and feedback. The constant force structure limiting rod provides a nearly constant, downward axial preload. When the ear rotates, the grinding disc can fit tightly against the grinding area of ​​the sealing surface, realizing adaptive precision grinding of the sealing surface with constant pressure, ensuring the uniformity of material removal rate and the consistency of processing accuracy.

[0016] Third, the test valve body, the second base, the annular airbag and the pressure sensor are used to cooperate. The test valve body acts as a simulated valve valve. The annular airbag is installed on the second base. After inflation, it expands circumferentially and forms a reliable dynamic seal at the lower end with the cylindrical surface of the valve cavity inner wall. Thus, together with the test valve body, they form a closed test space. With the help of the reaction structure, the air pressure of the test space is monitored to determine the sealing ability and the polishing quality of the sealing surface flange.

[0017] Fourth, the slender, straight narrow channel serves as the only radial conduction path connecting the central oil chamber and the annular oil groove, achieving damping isolation between the high and low pressure zones and dynamic pressure stability, thus ensuring the continuous uniformity of the injection flow. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the external three-dimensional structure of the present invention; Figure 2 For the present invention Figure 1 The right view; Figure 3 This is a schematic diagram of the external three-dimensional structure of the assembled test module of the present invention; Figure 4 This is a three-dimensional structural diagram of the adaptive grinding head in this invention; Figure 5 For the present invention Figure 4 The front view; Figure 6 For the present invention along Figure 5 A schematic diagram of the structure viewed in section AA; Figure 7 For the present invention along Figure 6 A schematic diagram of the cross-section at point BB; Figure 8 This is a schematic diagram of the external three-dimensional structure of the test module after disassembly in this invention; Figure 9 For the present invention Figure 8 The right view; Figure 10 For the present invention along Figure 9 A schematic diagram of the structure viewed in cross section CC; Figure 11 This is a simplified structural diagram of the internal structure of a valve in the prior art.

[0019] In the diagram: 1. Worktable; 2. Functional axis; 3. First base; 4. Ear; 5. Limiting rod; 6. Grinding disc; 7. Pressure sensor; 8. Rod cap; 9. Frame; 11. Central oil chamber; 12. Annular oil groove; 13. Narrow passage; 14. Micro-spray orifice; 15. Test valve; 16. Second base; 17. Annular airbag; 18. Cavity groove; 19. Air pressure sensor; 20. Rotary shaft sleeve; 21. Assembly frame; 22. Servo cylinder; 23. End face of sealing surface; 24. Cylindrical surface below the sealing end face of the valve cavity. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Please see Figures 1 to 11 The present invention provides a technical solution: an internal cavity polishing device for valve processing, comprising: The workbench 1 and its drive assembly have a functional shaft 2 rotatably mounted on the output end of the drive assembly. A first base 3 is fixedly mounted on the end of the functional shaft 2. An ear 4 extends outward from the top of the first base 3 and corresponds to the sealing surface of the valve cavity. Multiple adaptive grinding heads are arranged in a circumferential array on the ear 4. Multiple oil supply structures are also installed on the ear 4 between the grinding heads. The oil supply structure includes a central oil cavity 11 inside the first base 3. The central oil cavity 11 is designed coaxially with the first base 3. An annular oil groove 12 is opened in the interior of the first base 3 near the outer edge. The annular oil groove 12 surrounds the periphery of the central oil cavity 11. Multiple narrow passages 13 are also opened on the first base 3. The two ends of the narrow passages 13 are connected to the annular oil groove 12 and the central oil cavity 11, respectively. Multiple micro-spray holes 14 facing outward are opened through the inner wall of the annular oil groove 12.

[0022] In existing technologies, valves typically have small diameters and complex internal structures, creating a nearly enclosed and restricted working environment. This makes it difficult to continuously and effectively lubricate and cool the contact area between the grinding head and the sealing surface during grinding. However, in this invention, due to the structural design of the valve sealing surface, please refer to... Figure 11 Its sealing surface is designed with an annular flange, so the top of the flange needs to be ground and polished to form a sealing contact with the valve disc and to ensure that its sealing capacity meets the valve's usage requirements. Therefore, this invention designs the cooperation between the first base 3 and the ear 4 so that the first base 3 can enter the cylindrical surface 24 below the sealing end face of the valve cavity. At the same time, the adaptive grinding head on the ear 4 can abut against the flange of the sealing surface. With the cooperation of the drive assembly control function shaft 2, the first base 3 and the ear 4 to rotate, the adaptive grinding head distributed on the ear 4 will work to complete the grinding work on the flange of the sealing surface. Importantly, through the cooperation of the central oil cavity 11, the annular oil groove 12, the narrow channel 13 and the micro-spray hole 14, the central oil cavity 11 is used for storage. During the rotation of the first substrate 3, the oil medium is driven by centrifugal force, meaning that the mass of the object is subjected to centrifugal force. The oil medium is forcefully thrown towards the edge of the rotating body and connected through the intermediate channel 13. The channel 13 is a small channel with a diameter of 1 to 3 millimeters. The oil medium is accelerated here, and the centrifugal force begins to be converted into oil pressure. The oil medium entering the channel 13 is transferred to the outermost annular oil groove 12. Since the annular oil groove 12 is located at the maximum radius of the rotating body, the centrifugal force is strongest here, resulting in the highest oil pressure. This allows the oil medium to be output outward through the micro-spray hole 14. The high-pressure oil medium can be sprayed out in the form of a fine line or mist through the micro-spray hole 14, directly covering the polishing area, thereby achieving the polishing and oiling of the inner cavity.

[0023] In a preferred embodiment, the adaptive polishing head includes a limiting rod 5 that slides through the ear body 4. The top of the limiting rod 5 is designed with a rod cap 8, and a pressure sensor 7 is mounted on the lower surface of the rod cap 8. A constant force structure is fixedly installed between the pressure receiving surface of the pressure sensor 7 and the top of the ear body 4. The constant force structure provides a constant axial pressure to the limiting rod 5. A polishing disc 6 is detachably mounted at the bottom end of the limiting rod 5. (See also...) Figures 4 to 6 In the existing technology, the disadvantage of manual polishing is that the precision is inconsistent and the polishing pressure is sometimes large and sometimes small. However, in this embodiment, through the cooperation of constant force structure, limit rod 5 and rod cap 8, the polishing disc 6 can always be pressed on the flange of the sealing surface with the same force, so that the material removal rate of the polished part can be uniform and the problems of under-polishing and over-polishing can be avoided. The constant force structure can be a constant force spring, which can be sleeved on the outside of the limit rod 5.

[0024] Based on the adaptive grinding head embodiment, after fine grinding, a test valve body 15 is detachably installed at the bottom end of the limiting rod 5. The test valve body 15 is used to simulate the valve disc inside the valve cavity. A second base 16 is fixedly installed at the bottom of the test valve body 15. An air bladder seat is fixedly installed on the circumferential outer wall of the second base 16 near the bottom. An annular air bladder 17 is fixedly installed on the air bladder seat. After gas is injected into the annular air bladder 17, it can expand circumferentially. The outer wall of the annular air bladder 17 can abut against the cylindrical surface below the sealing surface of the valve cavity, so that a test space is formed between the annular air bladder 17, the second base 16, the test valve body 15 and the cylindrical surface. The annular air bladder 17 can be associated with an external positive pressure air source. A reaction structure for monitoring changes in air pressure in the test space is also installed on the second base 16. Please refer to [link to relevant documentation]. Figures 8 to 11 In this embodiment, after the polishing process, cleaning and testing are required to ensure that the end face 23 of the sealing surface meets the valve requirements. After the annular airbag 17 expands circumferentially, the outer wall of the annular airbag 17 can form a tight contact with the cylindrical surface 24 below the sealing end face of the valve cavity, thereby forming a test space and completing the lower sealing. The test valve 15 simulates the valve disc used in the valve cavity, so that the test valve 15 seals the top of the test space to create sealing conditions for subsequent testing. Since the test valve 15 is detachably installed at the end of the limiting rod 5, the test valve 15 can exert a certain axial pressure on the narrow passage 13, thereby ensuring the stability of the seal.

[0025] Furthermore, the reaction structure includes a cavity 18 formed inside the second substrate 16. The cavity 18 is connected to an external negative pressure air source, and the pipeline design does not interfere with the normal operation of the test space. A gas channel communicating with the test space is formed on the inner wall of the cavity 18. A pressure sensor 19 is fixedly installed on the outer wall of the second substrate 16 within the test space. In this embodiment, through the cooperation of the pressure sensor 19, the cavity 18, and the gas channel, when the external negative pressure air source draws air from the cavity 18, since the cavity 18 is connected to the test space through the gas channel, if the test space is sealed intact, the air pressure in the test space will gradually decrease. The pressure sensor 19 can monitor this in real time. If the seal of the test space fails, it may be due to the failure of the seal of the test valve 15 or the annular airbag 17. In the next test, it is only necessary to inject air pressure into the valve inlet to detect whether the annular airbag 17 has failed. If the annular airbag 17 fails, the air pressure inside the test space will increase.

[0026] The reaction structure and test space constitute a testable module, which can be freely disassembled and installed, improving the degree of automation and enabling batch testing or one-on-one testing.

[0027] In a preferred embodiment, the slit 13 is a straight channel designed along the radial line of the first substrate 3, and the micro-spray orifice 14 is designed to output downwards at an angle, facing the seat surface of the valve inner cavity sealing surface. By designing the slit 13, the slender slit 13 generates significant flow resistance to the oil flow, which effectively isolates the direct impact of oil volume fluctuations in the central oil cavity 11 on the pressure of the annular oil groove 12. Even if the oil level in the central oil cavity 11 fluctuates slightly due to replenishment, the pressure in the annular oil groove 12 can remain relatively stable, thereby ensuring uniform injection flow. Secondly, when the rotation speed changes suddenly, the oil channel resistance can buffer the transmission of pressure waves, prevent the system pressure from violently oscillating, and protect the precision microporous structure, thereby forming a damping isolation between the slit 13 and the annular oil groove 12.

[0028] In a preferred embodiment, the grinding disc 6 has a fan-shaped annular structure and is made of alloy steel with a Rockwell hardness of 40 or higher. A closed-cell polyurethane pad is attached to the grinding disc 6. The closed-cell polyurethane pad provides elastic cushioning and protects the precision geometry of the high-hardness sealing surface from damage. It can be combined with diamond plaster to obtain a true mirror surface without micro-cracks in a plastic flow manner, significantly improving the sealing performance and making the process stable and controllable.

[0029] In summary, the drive assembly further includes a frame 9 fixedly mounted on the workbench 1, an assembly frame 21 slidably mounted on the frame 9, the sliding direction of the assembly frame 21 being in the same direction as the axis of the first base 3, a servo motor and a rotating shaft sleeve 20 fixedly mounted on the assembly frame 21, the rotating shaft inside the rotating shaft sleeve 20 being fixedly connected to the functional shaft 2, and the output end of the servo motor being connected to the rotating shaft inside the rotating shaft sleeve 20 via a reducer.

[0030] Furthermore, the top of the worktable 1 has an assembly plate for mounting fixtures, and a servo cylinder 22 is fixedly mounted on the frame 9. The output end of the servo cylinder 22 is fixedly connected to the top of the assembly frame 21.

[0031] By utilizing the above-mentioned structures, the rotating centrifugal force is used to precisely spray the lubricating oil onto the grinding area. At the same time, the adaptive constant pressure grinding head ensures uniform grinding force and guarantees surface accuracy. Furthermore, the test module can verify the grinding quality by testing the sealing performance.

[0032] The standard parts used in this embodiment can be purchased directly from the market, and the non-standard structural parts described in the specification and drawings can also be processed without any doubt based on existing technical common sense. At the same time, the connection methods of each component adopt mature conventional methods in the existing technology, and the machinery, parts and equipment all adopt conventional models in the existing technology, so they will not be described in detail here.

[0033] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An internal cavity grinding device for valve processing, characterized in that: include: The workbench (1) and its drive assembly are provided. A functional shaft (2) is rotatably mounted on the output end of the drive assembly. A first base (3) is fixedly mounted on the end of the functional shaft (2). An ear (4) extends outward from the top of the first base (3). The ear (4) corresponds to the sealing surface of the valve cavity. Multiple adaptive grinding heads are arranged in a circumferential array on the ear (4). Multiple oil supply structures are also installed on the ear body (4) located between the grinding heads. The oil supply structure includes a central oil cavity (11) inside the first base (3). The central oil cavity (11) is designed coaxially with the first base (3). An annular oil groove (12) is opened in the interior of the first base (3) near the outer edge. The annular oil groove (12) surrounds the periphery of the central oil cavity (11). Multiple channels (13) are also opened on the first base (3). The two ends of the channel (13) are connected to the annular oil groove (12) and the central oil cavity (11) respectively. Multiple micro-spray holes (14) facing outward are opened through the inner wall of the annular oil groove (12).

2. The valve processing internal cavity polishing device according to claim 1, characterized in that: The adaptive polishing head includes a limiting rod (5) that slides through the ear body (4). The top of the limiting rod (5) is designed with a rod cap (8). A pressure sensor (7) is mounted on the lower surface of the rod cap (8). A constant force structure is fixedly installed between the pressure receiving surface of the pressure sensor (7) and the top of the ear body (4). The constant force structure is used to provide a constant axial pressure to the limiting rod (5). A polishing disc (6) is detachably installed at the bottom end of the limiting rod (5).

3. The valve processing internal cavity polishing device according to claim 2, characterized in that: After fine grinding, a test valve body (15) is detachably installed at the bottom of the limiting rod (5). The test valve body (15) is used to simulate the valve disc of the valve cavity. A second base (16) is fixedly installed at the bottom of the test valve body (15). An airbag seat is fixedly installed on the circumferential outer wall of the second base (16) near the bottom. An annular airbag (17) is fixedly installed on the airbag seat. After gas is injected into the annular airbag (17), it can expand circumferentially. The outer wall of the annular airbag (17) can abut against the cylindrical surface below the sealing surface of the valve cavity, so that a test space is formed between the annular airbag (17), the second base (16), the test valve body (15) and the cylindrical surface. The annular airbag (17) can be associated with an external positive pressure gas source. A reaction structure for monitoring the gas pressure change of the test space is also installed on the second base (16).

4. The valve processing internal cavity polishing device according to claim 3, characterized in that: The reaction structure includes a cavity (18) opened inside the second substrate (16). The cavity (18) is connected to an external negative pressure gas source, and the pipeline design does not interfere with the normal operation of the test space. The inner wall of the cavity (18) is provided with a gas channel connected to the test space. A pressure sensor (19) is fixedly installed on the outer wall of the second substrate (16) located in the test space.

5. The valve processing internal cavity polishing device according to claim 1, characterized in that: The slit (13) is a straight channel and is designed along the radial line of the first substrate (3). The micro-spray hole (14) is designed to be inclined downward and faces the seat surface of the valve inner cavity sealing surface.

6. The valve processing internal cavity polishing device according to claim 2, characterized in that: The grinding disc (6) has a fan-shaped ring structure and is made of alloy steel with a Rockwell hardness of 40 or higher. A closed-cell polyurethane pad is attached to the grinding disc (6).

7. The valve machining internal cavity polishing apparatus according to any one of claims 1-6, characterized in that: The drive assembly includes a frame (9) fixedly mounted on a workbench (1), an assembly frame (21) is slidably mounted on the frame (9), the sliding direction of the assembly frame (21) is in the same direction as the axis of the first base (3), a servo motor and a rotating shaft sleeve (20) are fixedly mounted on the assembly frame (21), the rotating shaft inside the rotating shaft sleeve (20) is fixedly connected to the functional shaft (2), and the output end of the servo motor is connected to the rotating shaft inside the rotating shaft sleeve (20) through a reducer.

8. The valve processing internal cavity polishing device according to claim 7, characterized in that: The top of the workbench (1) has an assembly plate for mounting fixtures, and a servo cylinder (22) is fixedly mounted on the frame (9). The output end of the servo cylinder (22) is fixedly connected to the top of the assembly frame (21).

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