A full-hard screw rod and a machining process thereof

Abstract

This invention provides a fully hardened screw and its processing technology. The fully hardened screw includes a screw shaft, which comprises a shank, a feed section, a compression section, and a discharge section. The feed section is fixedly installed at one end of the shank, the compression section is fixedly installed at one end of the feed section, and the discharge section is fixedly installed at one end of the compression section. The diameter of the discharge section is larger than the diameter of the feed section, and the diameter of one end of the compression section is the same as the diameter of the feed section, while the diameter of the other end of the compression section is the same as the diameter of the discharge section. The fully hardened screw and its processing technology provided by this invention have the advantages of improving performance and service life.

Description

Technical Field

[0001] This invention relates to the field of screw processing technology, and in particular to a fully hardened screw and its processing technology. Background Technology

[0002] Screws mainly refer to cylinders with helical grooves cut on their outer surfaces or cones with conical helical grooves cut on their outer surfaces. The former, cylindrical screws, are currently the most commonly used and closest to everyday life screw types.

[0003] However, these types of screws have a relatively short service life, generally around 11 months, and need to be replaced frequently, increasing the number of maintenance operations and thus raising maintenance costs.

[0004] Therefore, it is necessary to provide a new fully hardened screw and its processing technology to solve the above-mentioned technical problems. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a fully hardened screw and its processing technology that can improve performance and service life.

[0006] To solve the above-mentioned technical problems, the present invention provides a fully hardened screw comprising a screw, the screw comprising a shank, a feed section, a compression section, and a discharge section. The feed section is fixedly installed at one end of the shank, the compression section is fixedly installed at one end of the feed section, and the discharge section is fixedly installed at one end of the compression section. The diameter of the discharge section is larger than the diameter of the feed section, and the diameter of one end of the compression section is the same as the diameter of the feed section, and the diameter of the other end of the compression section is the same as the diameter of the discharge section.

[0007] Preferably, one end of the discharge section is provided with a countersunk hole, and a threaded groove is provided in the countersunk hole.

[0008] The present invention also provides a fully hardened screw manufacturing process comprising the following steps:

[0009] S1: Material taking: First, take out the bar stock and use a saw and steel ruler to cut it into the specified blanks, with a machining allowance reserved for both the outer diameter and length;

[0010] S2: Rough turning, using a conventional lathe, three-jaw chuck, calipers and thread gauge to rough turn the bar stock, and leave a machining allowance for its outer diameter;

[0011] S3: Rough milling, using a milling machine, double centers, follower post and calipers to rough mill the rough-turned bar stock, and leaving machining allowance for the tooth root and tooth crest after rough milling;

[0012] S4: Inspection. Use calipers and thread gauges to inspect the rough-milled bar stock. If the size is too large, continue rough turning and rough milling. If it is too small, start from S1 again until it meets the qualified standard.

[0013] S5: Quenching, using a pit-type high-temperature furnace to quench the qualified bar stock;

[0014] S6: Tempering, the quenched bar stock is tempered twice again using a pit-type high-temperature furnace;

[0015] S7: Hardness test, using a Rockwell hardness tester to test the hardness of the bar stock after two tempering processes.

[0016] S8: Tempering, using a tempering furnace to temper the qualified bar stock again to further consolidate its hardness;

[0017] S9: Hardness test. The Rockwell hardness tester is used to test the tempered bar stock to obtain bar stock that meets the hardness standard.

[0018] S10: Straightness detection and correction. First, use a press and runout tester to detect the straightness of the bar stock that meets the hardness standard. If the straightness does not meet the standard, it can be corrected by using a shim to ensure that the outer diameter runout is less than 0.3mm.

[0019] S11: The handle is softened by using a tempering furnace to reduce the hardness and tempering length of the handle, making it easier to process.

[0020] S12: Shank hardness test. The hardness of the shank is tested using a Rockwell hardness tester to ensure that it meets the processing standards.

[0021] S13: Rough grinding of the outer diameter of the shank. The outer diameter of the shank is rough ground using an outer diameter grinder, double centers and calipers, and a machining allowance is reserved.

[0022] S14: Rough grinding of screw threads. The screw threads are rough ground using a screw grinder, a three-jaw chuck, a center and calipers. After rough grinding, the screw threads have a machining allowance at both the root and the crest of the threads.

[0023] S15: Tempering, tempering the rough-ground screw to remove processing stress;

[0024] S16: Ultra-deep cryogenic treatment, which involves ultra-deep cryogenic treatment of the tempered screw to transform the residual austenite in its structure into martensite by increasing the degree of supercooling through deep cryogenic treatment, thereby making the surface structure and hardness of the workpiece uniform and enhancing its wear resistance and fatigue strength.

[0025] S17: Grinding and finishing of tooth base. The tooth base is ground and finished using a tooth base grinding machine, double centers, follower tool holder and calipers, and a machining allowance is reserved on the outer diameter of the tooth base;

[0026] S18: Polishing. The screw is polished using a polishing machine, double centers, follower holder and calipers to remove the machining allowance at the root and crest of the thread to achieve the final size and ensure the surface roughness.

[0027] S19: Outer diameter grinding and fine grinding. The outer diameter of the screw is ground and finely ground using an outer diameter grinding machine, double centers, follower tool holder and calipers to process the outer diameter to the drawing size and ensure roughness and straightness.

[0028] S20: Precision turning, using a CNC lathe, center rest, special fixture, calipers and steel ruler to perform precision turning, and to machine the inner and outer stops and the outer diameter of the shank;

[0029] S21: Milling splines, using a vertical milling machine, special fixtures, calipers and spline gauges to mill splines;

[0030] S22: Chamfering and fine polishing. The screw is chamfered and finely polished using a grinding wheel, polishing table and fine sandpaper to remove chamfer burrs from the screw surface and ensure roughness.

[0031] S23: The shank and outer stop are precision ground. The shank and outer stop are precision ground using an outer diameter grinding machine, a special fixture and an outer micrometer. The outer stop must not have a chamfer.

[0032] S24: Inspection. On the inspection table, the screw is inspected using a runout tester, calipers, micrometers and special inspection tools to ensure that it meets all standards.

[0033] S25: Cleaning, use a cloth and sandpaper to clean the screw and remove burrs and oil stains;

[0034] S26: Packaging, using packaging tools such as PVC pipes, rust-proof paper and foam paper to pack the screw to prevent it from being bumped or damaged;

[0035] S27: Warehousing. Use forklifts to store batches of finished screws in the warehouse, and the temperature, humidity and storage time of the storage environment must be predetermined.

[0036] Preferably, in step S1, a machining allowance of 5mm is reserved for both the outer diameter and length of the blank.

[0037] Preferably, in step S2, a 2mm machining allowance is reserved on the outer diameter of the rough-machined bar stock, and a hole and internal thread are machined in its center.

[0038] Preferably, in step S3, 2mm is reserved at the root and crest of the rough-milled bar stock.

[0039] Preferably, in step S13, a machining allowance of 0.5mm should be reserved on the shank after rough grinding.

[0040] Preferably, in S14, a machining allowance of 0.5mm is reserved at both the root and the crest of the screw.

[0041] Preferably, in step S17, the outer diameter of the tooth root after grinding and fine polishing is reserved by 0.1 mm.

[0042] Preferably, in step S25, the cleaned screw is coated with anti-rust oil to prevent rusting.

[0043] Compared with related technologies, the fully hardened screw and its processing technology provided by the present invention have the following beneficial effects:

[0044] This invention provides a fully hardened screw and its processing technology. By utilizing the conical shape of the compression section and the larger diameter of the discharge section, the overall service life of the screw is increased from 11 months to 16 months. Furthermore, through the aforementioned processing technology, the screw does not deform or break during actual production, is corrosion-resistant, has a long service life, and produces products with high yield, high efficiency, and good stability. Attached Figure Description

[0045] Figure 1 A flowchart of the fully hardened screw manufacturing process provided by this invention;

[0046] Figure 2 A schematic diagram of the structure of the fully hardened screw provided by the present invention;

[0047] Figure 3 This is a slanted view of the structure of the fully hardened screw provided by the present invention.

[0048] The numbers in the diagram are: 1. Screw; 101. Shank; 102. Feed section; 103. Compression section; 104. Discharge section; 2. Countersunk hole; 3. Threaded groove. Detailed Implementation

[0049] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0050] In this embodiment

[0051] Please refer to the following: Figures 1-3In the first embodiment of the present invention, the fully hardened screw includes: a screw 1, which includes a shank 101, a feed section 102, a compression section 103, and a discharge section 104. The entire shank 101, feed section 102, compression section 103, and discharge section 104 are made of WR650 material, a thermoplastic composite material that can withstand various high-temperature and corrosive environments, exhibiting strong overall performance. Furthermore, according to actual production needs, the screw 1 can be manufactured in gradient, general-purpose, and abrupt shapes. The feed section 102 is fixedly installed at one end of the shank 101, and this section represents a general proportional dimension in the screw 1. The compression section 103 is fixedly installed at one end of the feed section 102, and the discharge section 104 is fixedly installed at the other end of the compression section 103. The diameter of the discharge section 104 is larger than the diameter of the feed section 102, thus enabling… The portion of the screw 1 furthest from the shank 101 is thickened, reducing the impact of deflection on the entire screw 1 and thus improving its service life. Furthermore, the diameter of the end face of the compression section 103 that contacts the feed section 102 is the same as the diameter of the feed section 102, and the diameter of the end face of the compression section 103 that contacts the discharge section 104 is the same as the diameter of the discharge section 104. This makes the compression section 103 a frustum-shaped cone with a gradual transition, thereby progressively reducing the extrusion stress on the screw 1 during rotation, further improving the wear resistance and service life of the screw 1. Moreover, the maximum outer diameter of the threads on the feed section 102, compression section 103, and discharge section 104 is the same; only the inner diameter of the threads varies with the different sections. This ensures that the screw 1 can be smoothly screwed into the corresponding threaded hole.

[0052] In order to connect the screw 1 to the external object, a countersunk hole 2 is provided at one end of the discharge section 104, and a threaded groove 3 is provided in the countersunk hole 2, which is used to screw the screw 1 to the external object.

[0053] The working principle of the fully hardened screw provided by this invention is as follows:

[0054] In actual use, the discharge section 104 on the screw 1 first enters the threaded hole, and then with continuous rotation, the compression section 103 begins to enter the threaded hole, eventually causing the feed section 102 to also be screwed into the threaded hole. During the back-and-forth rotation of the screw 1, the size advantage of the compression section 103 and the discharge section 104 increases the service life of the screw 1.

[0055] Compared with related technologies, the fully hardened screw provided by the present invention has the following beneficial effects:

[0056] By utilizing the conical shape of the compression section 103 and the larger diameter of the discharge section 104, the overall service life of the screw 1 is increased from 11 months to 16 months.

[0057] This invention also provides a fully hardened screw manufacturing process, comprising the following steps:

[0058] S1: Material taking: First, take out the bar stock and use a saw and steel ruler to cut it into the specified blanks, with a machining allowance reserved for both the outer diameter and length;

[0059] S2: Rough turning, using a conventional lathe, three-jaw chuck, calipers and thread gauge to rough turn the bar stock, and leave a machining allowance for its outer diameter;

[0060] S3: Rough milling, using a milling machine, double centers, follower post and calipers to rough mill the rough-turned bar stock, and leaving machining allowance for the tooth root and tooth crest after rough milling;

[0061] S4: Inspection. Use calipers and thread gauges to inspect the rough-milled bar stock. If the size is too large, continue rough turning and rough milling. If it is too small, start from S1 again until it meets the qualified standard.

[0062] S5: Quenching, using a pit-type high-temperature furnace to quench the qualified bar stock;

[0063] S6: Tempering, the quenched bar stock is tempered twice again using a pit-type high-temperature furnace;

[0064] S7: Hardness test, using a Rockwell hardness tester to test the hardness of the bar stock after two tempering processes.

[0065] S8: Tempering, using a tempering furnace to temper the qualified bar stock again to further consolidate its hardness;

[0066] S9: Hardness test. The Rockwell hardness tester is used to test the tempered bar stock to obtain bar stock that meets the hardness standard.

[0067] S10: Straightness detection and correction. First, use a press and runout tester to detect the straightness of the bar stock that meets the hardness standard. If the straightness does not meet the standard, it can be corrected by using a shim to ensure that the outer diameter runout is less than 0.3mm.

[0068] S11: The handle is softened by using a tempering furnace to reduce the hardness and tempering length of the handle, making it easier to process.

[0069] S12: Shank hardness test. The hardness of the shank is tested using a Rockwell hardness tester to ensure that it meets the processing standards.

[0070] S13: Rough grinding of the outer diameter of the shank. The outer diameter of the shank is rough ground using an outer diameter grinder, double centers and calipers, and a machining allowance is reserved.

[0071] S14: Rough grinding of screw threads. The screw threads are rough ground using a screw grinder, a three-jaw chuck, a center and calipers. After rough grinding, the screw threads have a machining allowance at both the root and the crest of the threads.

[0072] S15: Tempering, tempering the rough-ground screw to remove processing stress;

[0073] S16: Ultra-deep cryogenic treatment, which involves ultra-deep cryogenic treatment of the tempered screw to transform the residual austenite in its structure into martensite by increasing the degree of supercooling through deep cryogenic treatment, thereby making the surface structure and hardness of the workpiece uniform and enhancing its wear resistance and fatigue strength.

[0074] S17: Grinding and finishing of tooth base. The tooth base is ground and finished using a tooth base grinding machine, double centers, follower tool holder and calipers, and a machining allowance is reserved on the outer diameter of the tooth base;

[0075] S18: Polishing. The screw is polished using a polishing machine, double centers, follower holder and calipers to remove the machining allowance at the root and crest of the thread to achieve the final size and ensure the surface roughness.

[0076] S19: Outer diameter grinding and fine grinding. The outer diameter of the screw is ground and finely ground using an outer diameter grinding machine, double centers, follower tool holder and calipers to process the outer diameter to the drawing size and ensure roughness and straightness.

[0077] S20: Precision turning, using a CNC lathe, center rest, special fixture, calipers and steel ruler to perform precision turning, and to machine the inner and outer stops and the outer diameter of the shank;

[0078] S21: Milling splines, using a vertical milling machine, special fixtures, calipers and spline gauges to mill splines;

[0079] S22: Chamfering and fine polishing. The screw is chamfered and finely polished using a grinding wheel, polishing table and fine sandpaper to remove chamfer burrs from the screw surface and ensure roughness.

[0080] S23: The shank and outer stop are precision ground. The shank and outer stop are precision ground using an outer diameter grinding machine, a special fixture and an outer micrometer. The outer stop must not have a chamfer.

[0081] S24: Inspection. On the inspection table, the screw is inspected using a runout tester, calipers, micrometers and special inspection tools to ensure that it meets all standards.

[0082] S25: Cleaning, use a cloth and sandpaper to clean the screw and remove burrs and oil stains;

[0083] S26: Packaging, using packaging tools such as PVC pipes, rust-proof paper and foam paper to pack the screw to prevent it from being bumped or damaged;

[0084] S27: Warehousing. Use forklifts to store batches of finished screws in the warehouse, and the temperature, humidity and storage time of the storage environment must be predetermined.

[0085] In S1, a machining allowance of 5mm is reserved for both the outer diameter and length of the blank.

[0086] In S2, a 2mm machining allowance is reserved on the outer diameter of the bar stock after rough machining, and a hole and internal thread are machined in its center.

[0087] In S3, 2mm is reserved for the root and crest of the rough-milled bar stock.

[0088] In S13, a machining allowance of 0.5mm should be reserved on the shank after rough grinding.

[0089] In S14, a machining allowance of 0.5mm is reserved for both the root and crest of the screw.

[0090] In S17, the outer diameter of the tooth root after grinding and fine grinding is reserved by 0.1mm according to the upper difference.

[0091] In S25, rust-preventive oil is applied to the cleaned screw to prevent rusting.

[0092] Through the above processing technology, the screw 1 is not deformed or broken during actual production, is corrosion resistant, has a long service life, and produces products with high yield, high efficiency, and good stability.

[0093] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A fully hardened screw machining process, characterized in that, Includes the following steps: S1: Material taking: First, take out the bar stock and use a saw and steel ruler to cut it into the specified blanks, with a machining allowance reserved for both the outer diameter and length; S2: Rough turning, using a conventional lathe, three-jaw chuck, calipers and thread gauge to rough turn the bar stock, and leave a machining allowance for its outer diameter; S3: Rough milling, using a milling machine, double centers, follower post and calipers to rough mill the rough-turned bar stock, and leaving machining allowance for the tooth root and tooth crest after rough milling; S4: Inspection. Use calipers and thread gauges to inspect the rough-milled bar stock. If the size is too large, continue rough turning and rough milling. If it is too small, start from S1 again until it meets the qualified standard. S5: Quenching, using a pit-type high-temperature furnace to quench the qualified bar stock; S6: Tempering, the quenched bar stock is tempered twice again using a pit-type high-temperature furnace; S7: Hardness test, using a Rockwell hardness tester to test the hardness of the bar stock after two tempering processes. S8: Tempering, using a tempering furnace to temper the qualified bar stock again to further consolidate its hardness; S9: Hardness test, using a Rockwell hardness tester to test the tempered bar stock; S10: Straightness detection and correction. First, use a press and runout tester to detect the straightness of the bar stock that meets the hardness standard. If the straightness does not meet the standard, it can be corrected by using a pad to ensure that the outer diameter runout is less than 0.3mm. S11: Soften the handle by using a tempering furnace; S12: Shank hardness test. The hardness of the shank is tested using a Rockwell hardness tester to ensure that it meets the processing standards. S13: Rough grinding of the outer diameter of the shank. The outer diameter of the shank is rough ground using an outer diameter grinder, double centers and calipers, and a machining allowance is reserved. S14: Rough grinding of screw threads. The screw threads are rough ground using a screw grinder, a three-jaw chuck, a center and calipers. After rough grinding, the screw threads have a machining allowance at both the root and the crest of the threads. S15: Tempering, the rough-ground screw is tempered to remove processing stress; S16: Ultra-deep cryogenic treatment, which involves ultra-deep cryogenic treatment of the tempered screw to transform the residual austenite in its microstructure into martensite; S17: Precision grinding of the tooth root. The tooth root is precision ground using a tooth root grinding machine, double centers, follower tool holder and calipers, and a machining allowance is reserved on the outer diameter of the tooth root. S18: Polishing, using a polishing machine, double centers, follower holder and calipers to polish the screw, removing the machining allowance at the root and crest of the thread; S19: Outer diameter fine grinding, using an outer diameter grinding machine, double centers, follower tool holder and calipers to finely grind the outer diameter of the screw; S20: Precision turning, using a CNC lathe, center rest, special fixture, calipers and steel ruler to perform precision turning, and to machine the inner and outer stops and the outer diameter of the shank; S21: Milling splines, using a vertical milling machine, special fixtures, calipers and spline gauges to mill splines; S22: Chamfering and fine polishing, using a grinding wheel, polishing table and fine sandpaper to chamfer and fine polish the screw; S23: The shank and outer stop are precision ground. The shank and outer stop are precision ground using an outer diameter grinding machine, a special fixture and an outer micrometer. The outer stop must not have a chamfer. S24: Inspection; S25: Cleaning; S26: Packaging; S27: Warehousing.

2. The fully hardened screw processing technology according to claim 1, characterized in that, In S1, a machining allowance of 5mm is reserved for both the outer diameter and length of the blank.

3. The fully hardened screw processing technology according to claim 1, characterized in that, In S2, a 2mm machining allowance is reserved on the outer diameter of the bar stock after rough machining, and a hole and internal thread are machined in its center.

4. The fully hardened screw processing technology according to claim 1, characterized in that, In step S3, 2mm is reserved for the root and crest of the rough-milled bar stock.

5. The fully hardened screw processing technology according to claim 1, characterized in that, In S13, a machining allowance of 0.5mm needs to be reserved on the rough-ground shank.

6. The fully hardened screw processing technology according to claim 1, characterized in that, In S14, a machining allowance of 0.5mm is reserved at both the root and the crest of the screw.

7. The fully hardened screw processing technology according to claim 1, characterized in that, In S17, the outer diameter of the tooth root after fine grinding is reserved by 0.1mm according to the upper difference.

8. The fully hardened screw processing technology according to claim 1, characterized in that, In step S25, rust-preventive oil is applied to the cleaned screw to prevent rusting.

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