High-precision high-pressure oil film anti-lock screw and its grinding processing method

Abstract

The application discloses a high-precision high-pressure oil film anti-locking screw thread and a grinding processing method thereof, which comprises a screw thread pressure bearing working surface, a thread surface wave surface and a lubricating oil film. The screw thread pressure bearing working surface has roughness in the radial direction, the roughness is Ra0.8, and the thread surface wave surface is ground on the screw thread pressure bearing working surface. The thread surface wave surface is a uniformly distributed and weakly wavy concave-convex surface ground in the direction of the peripheral generatrix track of the screw thread pressure bearing working surface. The lubricating oil film is formed on the concave surface when the screw and nut pair moves relatively. The application effectively enables the rolling mill and other equipment to operate under high load and high pressure. The screw thread has high roughness to reduce the friction coefficient and high pressure lubricating film to prevent the screw thread from being locked due to vacuum and other problems, thereby ensuring the safe operation of the rolling mill and other large equipment.

Description

Technical Field

[0001] This invention relates to the technical field, specifically to a high-precision, high-pressure oil film anti-lock screw thread and its grinding process. Background Technology

[0002] The steel and non-ferrous metals manufacturing industry is the foundation of the national economy and a barometer of a country's manufacturing strength. Metallurgical rolling mills are important pieces of equipment in the production and manufacturing of steel and non-ferrous metals, and the pressing screw is a key core component of the rolling mill.

[0003] The existing defects in the threads of the press-down screw are:

[0004] 1. Patent document CN104853880A discloses a grinding process method, which "controls a feed table that moves the grinding wheel and the workpiece back and forth relative to each other, so that the grinding wheel and the workpiece are in contact while rotating and passing through a no-load travel that can achieve safe contact, thereby grinding the surface of the workpiece. After grinding the workpiece to the target position, when the position of the grinding wheel returns to the starting position, when the mechanical elastic deformation included in the displacement of the feed table is negligible, the position or displacement of the feed table is measured, and a correction value for the start position of the no-load travel is calculated based on the position or displacement of the feed table, and the start position of the next no-load travel is corrected based on the correction value." However, the existing press-down screw threads cannot reduce the phenomenon of screws and nuts seizing during the rolling process, making the rolling production unsafe, unstable and discontinuous.

[0005] 2. Patent document CN108284353A discloses a grinding processing apparatus and a grinding processing method. "The grinding processing apparatus includes: a grinding wheel side vibration displacement calculation device, which calculates the vibration displacement of the grinding wheel caused by the vibration in the near separation direction caused by the imbalance of the grinding wheel around the axis of rotation; a spindle side vibration displacement calculation device, which calculates the vibration displacement of the workpiece caused by the vibration in the near separation direction of the grinding wheel propagating from the grinding wheel seat to the bed; a relative vibration displacement calculation unit, which calculates the relative vibration displacement between the grinding wheel and the workpiece based on the calculated vibration displacement of the grinding wheel and the vibration displacement of the workpiece; a position changing unit, which generates a position changing command to change the position of the grinding wheel seat based on the calculated relative vibration displacement between the grinding wheel and the workpiece; and a processing control unit, which performs grinding processing on the workpiece based on the generated position changing command." However, the existing press-down screw threads cannot reduce the phenomenon of screws and nuts seizing during the rolling process, making the rolling mill production unsafe, unstable, and discontinuous. Summary of the Invention

[0006] The purpose of this invention is to provide a high-precision, high-pressure oil film anti-locking screw thread and its grinding processing method, so as to solve the technical problem mentioned in the background art that the screw thread cannot reduce the phenomenon of screw and nut seizing during the rolling process, resulting in unsafe, unstable and discontinuous rolling production.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a high-precision, high-pressure oil film anti-lock screw thread, comprising a thread bearing working surface, a thread wavy surface, and a lubricating oil film. The thread bearing working surface has a radial roughness of Ra0.8. A thread wavy surface is ground on the thread bearing working surface. The thread wavy surface is a uniformly distributed, slightly wavy concave-convex surface ground along the peripheral generatrix trajectory of the screw thread bearing working surface. When the screw and nut pair move relative to each other, a lubricating oil film is formed on the concave surface of the thread wavy surface.

[0008] Preferably, the lubricating oil film reduces the risk of jamming or seizing of the pressing screws and nuts of equipment such as rolling mills operating in harsh environments with continuous high load and high pressure.

[0009] Preferably, the tooth surface wave surface is a concave-convex surface with a peak-to-valley difference of 0.0001~0.0005mm.

[0010] Preferably, the screw thread is produced by grinding. During grinding, the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation move in opposite directions. The linear speed of the screw thread rotation is adjustable, while the linear speed of the grinding wheel rotation is relatively fixed. By adjusting the difference in relative motion speed between the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation, the roughness of the screw thread's pressure-bearing working surface and the formation of a wavy surface are achieved. The increased roughness reduces the coefficient of friction, and the wavy surface of the screw thread serves as a storage space for a high-pressure oil film.

[0011] Preferably, during the grinding process, the rotational linear velocity direction of the thread is opposite to the rotational linear velocity direction of the grinding wheel.

[0012] Preferably, during the grinding process, the linear velocity of the screw thread rotation is used as an adjustment parameter for the relative grinding speed, and this parameter is 0.02~0.06 m / s.

[0013] Preferably, during the grinding process, the rotational linear velocity of the grinding wheel is selected as a safe linear velocity, which is 30~35 m / s.

[0014] Preferably, after grinding, the tooth surface of the screw thread bearing working surface has obvious wavy patterns, no unevenness to the touch, and a roughness of Ra0.8.

[0015] Preferably, the experimental procedure for determining the linear velocity of the screw thread rotation is as follows;

[0016] S1. The precision-machined screws are clamped and fixed on a grinding machine using a double-pin clamping method.

[0017] S2. Install and adjust the grinding wheel power head for grinding threads into place.

[0018] S3. Use diamond tools to grind the working surface angle of the grinding wheel to make it conform to the bearing working surface or back support surface of the screw thread.

[0019] S4. On the grinding machine, place the grinding wheel and the screw thread grinding face together to find the starting point of dynamic grinding.

[0020] S5. After finding the starting point of grinding, rotate the grinding wheel normally to start the trial grinding.

[0021] S6. After the trial grinding of the grinding wheel begins, the optimal linear speed of the screw thread is determined by adjusting the rotational linear speed of the screw thread.

[0022] S7. During trial grinding, the linear speed of the thread rotation should be gradually increased from 0. After each increase of 0.005 m / s, the acceleration should be stopped and the data recorded. This process of trial grinding and recording should be repeated until the optimal parameters are obtained. After that, the linear speed of the thread rotation should be fixed and normal grinding should begin. The optimal parameters are 0.02~0.06 m / s.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] 1. This invention, by installing a device that effectively enables rolling mills and other equipment to operate under high load and high pressure conditions, ensures that the screw threads have both high roughness to reduce the coefficient of friction and high pressure to generate a lubricating film to prevent problems such as vacuum formation on the screw thread surface, thus preventing seizing and ensuring the safe operation of large equipment such as rolling mills.

[0025] 2. This invention utilizes a high-pressure oil film formed between the crests and troughs of the bolts. This high-pressure oil film ensures that during the movement of the screw and nut assembly, there will be no overheating due to insufficient oil on the thread surface or vacuum caused by an overly smooth working surface of the screw and nut threads, thus preventing jamming or seizing. This guarantees the reliable and stable operation of the rolling mill. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the threaded pressure-bearing working surface structure of the present invention;

[0027] Figure 2 This is a schematic diagram of the tooth surface wave structure of the present invention;

[0028] Figure 3 This is a schematic diagram of the lubricating oil film structure of the present invention.

[0029] In the diagram: 1. Thread bearing working surface; 3. Thread wavy surface; 5. Lubricating oil film. Detailed Implementation

[0030] 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.

[0031] In the description of this invention, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0032] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installed," "equipped with," "connected," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand this according to the specific circumstances.

[0033] Example 1: Please refer to Figure 1 , Figure 2 , Figure 3This invention provides an embodiment of a high-precision, high-pressure oil film anti-locking screw thread, comprising a screw thread bearing working surface 1, a tooth surface wave surface 3, and a lubricating oil film 5. The screw thread bearing working surface 1 has a radial roughness of Ra0.8. The tooth surface wave surface 3 is ground on the screw thread bearing working surface 1. The tooth surface wave surface 3 is a uniformly distributed, slightly wavy surface that is ground along the peripheral generatrix trajectory of the screw thread bearing working surface 1. When the screw and nut pair move relative to each other, the tooth surface wave surface 3 forms a lubricating oil film 5 on the concave surface. The lubricating oil film 5 reduces the risk of screw and nut jamming or seizing accidents when rolling mills and other equipment operate under harsh environments of continuous high load and high pressure. The tooth surface wave surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0001mm. The screw thread is processed by grinding. During grinding, the rotational linear speed of the screw thread and the rotational linear speed of the grinding wheel move in opposite directions. The rotational linear speed of the screw thread is adjustable. The speed of the grinding wheel rotation is relatively fixed. By adjusting the relative motion speed difference between the screw thread rotation speed and the grinding wheel rotation speed, the roughness of the screw thread bearing working surface 1 and the formation of the tooth surface wave surface 3 are achieved. The increase in roughness reduces the friction coefficient. The tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the direction of the screw thread rotation speed is opposite to the direction of the grinding wheel rotation speed. During grinding, the screw thread rotation speed is used as an adjustment parameter for the relative grinding speed. This parameter is 0.02 m / s. During grinding, the grinding wheel rotation speed is selected as a safe speed, which is 30 m / s. After grinding, the tooth surface wave surface 3 on the screw thread bearing working surface 1 has obvious wavy patterns. The tooth surface wave surface 3 has no unevenness to the touch. The roughness of the tooth surface wave surface 3 is Ra0.8. The experimental process of screw thread rotation speed is as follows:

[0034] S1. The precision-machined screws are clamped and fixed on a grinding machine using a double-pin clamping method.

[0035] S2. Install and adjust the grinding wheel power head for grinding threads into place.

[0036] S3. Use diamond tools to grind the working surface angle of the grinding wheel so that it conforms to the screw thread bearing working surface 1 or the screw thread back support surface 2.

[0037] S4. On the grinding machine, place the grinding wheel and the screw thread grinding face together to find the starting point of dynamic grinding.

[0038] S5. After finding the starting point of grinding, rotate the grinding wheel normally to start the trial grinding.

[0039] S6. After the trial grinding of the grinding wheel begins, the optimal linear speed of the screw thread is determined by adjusting the rotational linear speed of the screw thread.

[0040] S7. During trial grinding, the linear speed of the thread rotation should be gradually increased from 0. After each acceleration of 0.005 m / s, the acceleration should be stopped and the data recorded. This process of trial grinding and recording should be repeated until the optimal parameters are obtained. After that, the linear speed of the thread rotation should be fixed and normal grinding should begin. The optimal parameters are 0.02 m / s.

[0041] Example 2: Please refer to Figure 1 , Figure 2 , Figure 3 This invention provides an embodiment of a high-precision, high-pressure oil film anti-locking screw thread, comprising a screw thread bearing working surface 1, a tooth surface wave surface 3, and a lubricating oil film 5. The screw thread bearing working surface 1 has a radial roughness of Ra0.8. The tooth surface wave surface 3 is ground on the screw thread bearing working surface 1. The tooth surface wave surface 3 is a uniformly distributed, slightly wavy surface that is ground along the peripheral generatrix trajectory of the screw thread bearing working surface 1. When the screw and nut pair move relative to each other, the tooth surface wave surface 3 forms a lubricating oil film 5 on the concave surface. The lubricating oil film 5 reduces the risk of screw and nut jamming or seizing accidents when rolling mills and other equipment operate under harsh environments of continuous high load and high pressure. The tooth surface wave surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0003mm. The screw thread is processed by grinding. During grinding, the rotational linear speed of the screw thread and the rotational linear speed of the grinding wheel move in opposite directions. The rotational linear speed of the screw thread is adjustable. The speed of the grinding wheel rotation is relatively fixed. By adjusting the difference in relative motion speed between the screw thread rotation speed and the grinding wheel rotation speed, the roughness of the screw thread bearing working surface 1 and the formation of the tooth surface wave surface 3 are achieved. The increase in roughness reduces the friction coefficient. The tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the direction of the screw thread rotation speed is opposite to the direction of the grinding wheel rotation speed. During grinding, the screw thread rotation speed is used as an adjustment parameter for the relative grinding speed. This parameter is 0.03 m / s. During grinding, the grinding wheel rotation speed is selected as a safe speed, which is 33 m / s. After grinding, the tooth surface wave surface 3 on the screw thread bearing working surface 1 has obvious wavy patterns. The tooth surface wave surface 3 has no unevenness to the touch. The roughness of the tooth surface wave surface 3 is Ra0.8. The experimental process of screw thread rotation speed is as follows:

[0042] S1. The precision-machined screws are clamped and fixed on a grinding machine using a double-pin clamping method.

[0043] S2. Install and adjust the grinding wheel power head for grinding threads into place.

[0044] S3. Use diamond tools to grind the working surface angle of the grinding wheel so that it conforms to the screw thread bearing working surface 1 or the screw thread back support surface 2.

[0045] S4. On the grinding machine, place the grinding wheel and the screw thread grinding face together to find the starting point of dynamic grinding.

[0046] S5. After finding the starting point of grinding, rotate the grinding wheel normally to start the trial grinding.

[0047] S6. After the trial grinding of the grinding wheel begins, the optimal linear speed of the screw thread is determined by adjusting the rotational linear speed of the screw thread.

[0048] S7. During trial grinding, the linear speed of the thread rotation should be gradually increased from 0. After each acceleration of 0.005 m / s, the acceleration should be stopped and the data recorded. This process of trial grinding and recording should be repeated until the optimal parameters are obtained. After that, the linear speed of the thread rotation should be fixed and normal grinding should begin. The optimal parameters are 0.03 m / s.

[0049] Example 3: Please refer to Figure 1 , Figure 2 , Figure 3 This invention provides an embodiment of a high-precision, high-pressure oil film anti-locking screw thread, comprising a screw thread bearing working surface 1, a tooth surface wave surface 3, and a lubricating oil film 5. The screw thread bearing working surface 1 has a radial roughness of Ra0.8. The tooth surface wave surface 3 is ground on the screw thread bearing working surface 1. The tooth surface wave surface 3 is a uniformly distributed, slightly wavy surface that is ground along the peripheral generatrix trajectory of the screw thread bearing working surface 1. When the screw and nut pair move relative to each other, the tooth surface wave surface 3 forms a lubricating oil film 5 on the concave surface. The lubricating oil film 5 reduces the risk of screw and nut jamming or seizing accidents when rolling mills and other equipment operate under harsh environments of continuous high load and high pressure. The tooth surface wave surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0002mm. The screw thread is processed by grinding. During grinding, the rotational linear speed of the screw thread and the rotational linear speed of the grinding wheel move in opposite directions. The rotational linear speed of the screw thread is adjustable. The speed of the grinding wheel rotation is relatively fixed. By adjusting the difference in relative motion speed between the screw thread rotation speed and the grinding wheel rotation speed, the roughness of the screw thread bearing working surface 1 and the formation of the tooth surface wave surface 3 are achieved. The increase in roughness reduces the friction coefficient. The tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the direction of the screw thread rotation speed is opposite to the direction of the grinding wheel rotation speed. During grinding, the screw thread rotation speed is used as an adjustment parameter for the relative grinding speed. This parameter is 0.02 m / s. During grinding, the grinding wheel rotation speed is selected as a safe speed, which is 32 m / s. After grinding, the tooth surface wave surface 3 on the screw thread bearing working surface 1 has obvious wavy patterns. The tooth surface wave surface 3 has no unevenness to the touch. The roughness of the tooth surface wave surface 3 is Ra0.8. The experimental process of screw thread rotation speed is as follows:

[0050] S1. The precision-machined screws are clamped and fixed on a grinding machine using a double-pin clamping method.

[0051] S2. Install and adjust the grinding wheel power head for grinding threads into place.

[0052] S3. Use diamond tools to grind the working surface angle of the grinding wheel so that it conforms to the screw thread bearing working surface 1 or the screw thread back support surface 2.

[0053] S4. On the grinding machine, place the grinding wheel and the screw thread grinding face together to find the starting point of dynamic grinding.

[0054] S5. After finding the starting point of grinding, rotate the grinding wheel normally to start the trial grinding.

[0055] S6. After the trial grinding of the grinding wheel begins, the optimal linear speed of the screw thread is determined by adjusting the rotational linear speed of the screw thread.

[0056] S7. During trial grinding, the linear speed of the thread rotation should be gradually increased from 0. After each acceleration of 0.005 m / s, the acceleration should be stopped and the data recorded. This process of trial grinding and recording should be repeated until the optimal parameters are obtained. After that, the linear speed of the thread rotation should be fixed and normal grinding should begin. The optimal parameters are 0.02 m / s.

[0057] Example 4: Please refer to Figure 1 , Figure 2 , Figure 3This invention provides an embodiment of a high-precision, high-pressure oil film anti-locking screw thread, comprising a screw thread bearing working surface 1, a tooth surface wave surface 3, and a lubricating oil film 5. The screw thread bearing working surface 1 has a radial roughness of Ra0.8. The tooth surface wave surface 3 is ground on the screw thread bearing working surface 1. The tooth surface wave surface 3 is a uniformly distributed, slightly wavy surface that is ground along the peripheral generatrix trajectory of the screw thread bearing working surface 1. When the screw and nut pair move relative to each other, the tooth surface wave surface 3 forms a lubricating oil film 5 on the concave surface. The lubricating oil film 5 reduces the risk of screw and nut jamming or seizing accidents when rolling mills and other equipment operate under harsh environments of continuous high load and high pressure. The tooth surface wave surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0004 mm. The screw thread is processed by grinding. During grinding, the rotational linear speed of the screw thread and the rotational linear speed of the grinding wheel move in opposite directions. The rotational linear speed of the screw thread is adjustable. The speed of the grinding wheel rotation is relatively fixed. By adjusting the relative motion speed difference between the screw thread rotation speed and the grinding wheel rotation speed, the roughness of the screw thread bearing working surface 1 and the formation of the tooth surface wave surface 3 are achieved. The increase in roughness reduces the friction coefficient. The tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the direction of the screw thread rotation speed is opposite to the direction of the grinding wheel rotation speed. During grinding, the screw thread rotation speed is used as an adjustment parameter for the relative grinding speed. This parameter is 0.04 m / s. During grinding, the grinding wheel rotation speed is selected as a safe speed, which is 34 m / s. After grinding, the tooth surface wave surface 3 on the screw thread bearing working surface 1 has obvious wavy patterns. The tooth surface wave surface 3 has no unevenness to the touch. The roughness of the tooth surface wave surface 3 is Ra0.8. The experimental process of screw thread rotation speed is as follows:

[0058] S1. The precision-machined screws are clamped and fixed on a grinding machine using a double-pin clamping method.

[0059] S2. Install and adjust the grinding wheel power head for grinding threads into place.

[0060] S3. Use diamond tools to grind the working surface angle of the grinding wheel so that it conforms to the screw thread bearing working surface 1 or the screw thread back support surface 2.

[0061] S4. On the grinding machine, place the grinding wheel and the screw thread grinding face together to find the starting point of dynamic grinding.

[0062] S5. After finding the starting point of grinding, rotate the grinding wheel normally to start the trial grinding.

[0063] S6. After the trial grinding of the grinding wheel begins, the optimal linear speed of the screw thread is determined by adjusting the rotational linear speed of the screw thread.

[0064] S7. During trial grinding, the linear speed of the thread rotation should be gradually increased from 0. After each acceleration of 0.005 m / s, the acceleration should be stopped and the data recorded. This process of trial grinding and recording should be repeated until the optimal parameters are obtained. After that, the linear speed of the thread rotation should be fixed and normal grinding should begin. The optimal parameters are 0.04 m / s.

[0065] Comparative experiment:

[0066] The difference between Comparative Example 1 and Example 1 is that;

[0067] The wavy surface 3 forms a lubricating oil film 5 on the concave surface during the relative movement of the screw and nut pair. This lubricating oil film 5 reduces the risk of jamming or seizing of the screw and nut when operating equipment such as rolling mills under continuous high load and high pressure conditions. The wavy surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0001mm. The screw threads are machined by grinding. During grinding, the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation are opposite to each other. The linear speed of the screw thread rotation is adjustable, while the linear speed of the grinding wheel rotation is relatively fixed. The screw thread rotation speed and the grinding wheel rotation speed are adjusted accordingly. The difference in relative motion speed generated by the rotational linear speed improves the roughness of the thread bearing working surface 1 and forms the tooth surface wave surface 3. The improved roughness reduces the friction coefficient, and the tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the rotational linear speed of the thread is opposite to that of the grinding wheel. During grinding, the rotational linear speed of the screw thread is used as an adjustment parameter for the relative grinding speed, and this parameter is 0.02 m / s. During grinding, the selection of the grinding wheel rotational linear speed is a safe linear speed, which is 30 m / s.

[0068] The difference between Comparative Example 1 and Example 2 is that;

[0069] When the screw and nut pair move relative to each other, the wavy surface 3 forms a lubricating oil film 5 on the concave surface. The lubricating oil film 5 reduces the risk of jamming or seizing of the screw and nut when the rolling mill and other equipment operate under harsh environments of continuous high load and high pressure. The wavy surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0003mm. The screw threads are ground. During grinding, the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation are opposite to each other. The linear speed of the screw thread rotation is adjustable, while the linear speed of the grinding wheel rotation is relatively fixed. By adjusting the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation... The difference in relative motion speed generated by the rotational linear speed improves the roughness of the thread bearing working surface 1 and forms the tooth surface wave surface 3. The improved roughness reduces the friction coefficient, and the tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the rotational linear speed of the thread is opposite to that of the grinding wheel. During grinding, the rotational linear speed of the screw thread is used as an adjustment parameter for the relative grinding speed, and this parameter is 0.03 m / s. During grinding, the selection of the grinding wheel rotational linear speed is a safe linear speed, which is 33 m / s.

[0070] The difference between Comparative Example 1 and Example 3 is that;

[0071] When the screw and nut pair move relative to each other, the wavy surface 3 forms a lubricating oil film 5 on the concave surface. The lubricating oil film 5 reduces the risk of jamming or seizing of the screw and nut when the rolling mill and other equipment operate under harsh environments of continuous high load and high pressure. The wavy surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0002mm. The screw threads are machined by grinding. During grinding, the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation are opposite to each other. The linear speed of the screw thread rotation is adjustable, while the linear speed of the grinding wheel rotation is relatively fixed. By adjusting the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation... The difference in relative motion speed generated by the rotational linear speed improves the roughness of the thread bearing working surface 1 and forms the tooth surface wave surface 3. The improved roughness reduces the friction coefficient, and the tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the rotational linear speed of the thread is opposite to that of the grinding wheel. During grinding, the rotational linear speed of the screw thread is used as an adjustment parameter for the relative grinding speed, and this parameter is 0.02 m / s. During grinding, the selection of the grinding wheel rotational linear speed is a safe linear speed, which is 32 m / s.

[0072] The difference between Comparative Example 1 and Example 4 is that;

[0073] When the screw and nut pair move relative to each other, the wavy surface 3 forms a lubricating oil film 5 on the concave surface. The lubricating oil film 5 reduces the risk of jamming or seizing of the screw and nut when the rolling mill and other equipment operate under harsh environments of continuous high load and high pressure. The wavy surface 3 is a concave-convex surface with a peak-to-valve difference of 0.0004mm. The screw threads are machined by grinding. During grinding, the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation are opposite to each other. The linear speed of the screw thread rotation is adjustable, while the linear speed of the grinding wheel rotation is relatively fixed. By adjusting the linear speed of the screw thread rotation and the linear speed of the grinding wheel rotation... The difference in relative motion speed generated by the rotational linear speed improves the roughness of the thread bearing working surface 1 and forms the tooth surface wave surface 3. The improved roughness reduces the friction coefficient, and the tooth surface wave surface 3 serves as a storage space for high-pressure oil film. During grinding, the rotational linear speed of the thread is opposite to that of the grinding wheel. During grinding, the rotational linear speed of the screw thread is used as an adjustment parameter for the relative grinding speed, and this parameter is 0.04 m / s. During grinding, the selection of the grinding wheel rotational linear speed is a safe linear speed, which is 34 m / s.

[0074] The screw threads of Embodiments 1, 2, 3, 4, and 5 of the present invention were compared with those of conventional screw threads (Comparative Example 1) by conducting friction coefficient and seizure rate experiments, and the values ​​were calculated and statistically analyzed. The results are shown in the table.

[0075]

[0076] The data in the table shows that the friction coefficients of the screw threads in Examples 1, 2, 3, 4 and 5 of the present invention are 0.08, 0.09, 0.10 and 0.011, respectively, which are significantly lower than the friction coefficients of the screw threads in Comparative Example 1. Therefore, it is shown that the friction coefficient of the screw threads in the present invention is significantly reduced.

[0077] The data in the table shows that the seizure rates of the screw threads in Examples 1, 2, 3, 4, and 5 of this invention are 3, 4, 2, and 4, respectively, which are significantly lower than the seizure rate of the screw threads in Comparative Example 1. Therefore, this indicates that the seizure rate of the screw threads in this invention is significantly reduced.

[0078] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A method for machining high-precision high-pressure oil film anti-locking screw threads, wherein the screw threads include a thread bearing working surface (1), a thread wave surface (3), and a lubricating oil film (5), wherein the thread bearing working surface (1) has a roughness in the radial direction, the roughness being Ra0.8, and a thread wave surface (3) is ground on the thread bearing working surface (1), the thread wave surface (3) being a uniformly distributed, slightly wavy concave-convex surface ground along the peripheral generatrix trajectory of the screw thread bearing working surface (1), and the thread wave surface (3) forming a lubricating oil film (5) on the concave surface during the relative movement of the screw and nut pair, characterized in that: The processing method is as follows: The screw thread is processed by grinding. During grinding, the rotational linear speed of the screw thread and the rotational linear speed of the grinding wheel move in opposite directions. The rotational linear speed of the screw thread is adjustable, while the rotational linear speed of the grinding wheel is relatively fixed. By adjusting the difference in relative motion speed between the rotational linear speed of the screw thread and the rotational linear speed of the grinding wheel, the roughness of the screw thread bearing working surface (1) and the formation of the tooth surface wave surface (3) are achieved. The increase in roughness reduces the friction coefficient, and the tooth surface wave surface (3) serves as a storage space for high-pressure oil film. During the grinding process, the rotational linear speed of the screw thread is used as an adjustment parameter for the relative grinding speed. This parameter is 0.02~0.06 m / s. The experimental process for the rotational linear speed of the screw thread is as follows: S1. The precision-machined screws are clamped and fixed on a grinding machine using a double-pin clamping method. S2. Install and adjust the grinding wheel power head for grinding the screw threads into place; S3. Use diamond tools to grind the working surface angle of the grinding wheel so that it conforms to the screw thread bearing working surface (1) or the screw thread back support surface. S4. On the grinding machine, place the grinding wheel and the screw thread grinding face together as the cutting tool, and find the starting point of dynamic grinding. S5. After finding the starting point of grinding, rotate the grinding wheel normally to start the trial grinding. S6. After the trial grinding of the grinding wheel begins, the optimal linear speed of the screw thread is determined by adjusting the rotational linear speed of the screw thread. S7. During trial grinding, the linear speed of the thread rotation should be gradually increased from 0. After each increase of 0.005 m / s, the acceleration should be stopped and the data recorded. This process of trial grinding and recording should be repeated until the optimal parameters are obtained. After that, the linear speed of the thread rotation should be fixed and normal grinding should begin. The optimal parameters are 0.02~0.06 m / s.

2. The machining method for high-precision high-pressure oil film anti-locking screw threads according to claim 1, characterized in that: The lubricating oil film (5) reduces the risk of jamming or seizing of the pressing screws and nuts when the rolling mill is operating in a harsh environment of continuous high load and high pressure.

3. The machining method for high-precision high-pressure oil film anti-locking screw threads according to claim 1, characterized in that: The tooth surface wave surface (3) is a concave-convex surface with a peak-to-valley difference of 0.0001~0.0005mm.

4. The machining method for high-precision high-pressure oil film anti-locking screw threads according to claim 1, characterized in that: During the grinding process, the direction of the linear velocity of the screw thread is opposite to the direction of the linear velocity of the grinding wheel.

5. The machining method for high-precision high-pressure oil film anti-locking screw threads according to claim 1, characterized in that: During the grinding process, the selection of the grinding wheel rotation linear speed value is a safe linear speed, which is 30~35 m / s.

6. The machining method for high-precision high-pressure oil film anti-locking screw threads according to claim 1, characterized in that: After the grinding is completed, the tooth surface wave surface (3) on the screw thread bearing working surface (1) has obvious wave patterns, the tooth surface wave surface (3) has no unevenness when touched, and the roughness of the tooth surface wave surface (3) is Ra0.8.

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