A processing method of a flange nut with insurance function

Abstract

The application provides a processing method of a flange nut with an insurance function, and comprises the following steps: material preparation, rough turning, lubrication, warm / hot upsetting, heat treatment, fine turning, tapping, wire cutting, deburring, intermediate inspection, closing, and aging treatment. The bar material is hot forged into a shape through a die, the effective distance of the hexagonal wrench twisting and the size of the flange face are ensured, the transfer time is effectively controlled, the bar material is quickly upset after being heated, the heating fever phenomenon is avoided, the consistency of the size is controlled through numerical control precision machining equipment, the production efficiency is improved, the product size is ensured, the part quality is stable, the taper special closing die is used, the closing of the locking part is carried out through a hydraulic equipment, the consistency of the size of the closing part and the stability of the locking performance are ensured, the inner thread surface is plated with copper through surface treatment, the seizing phenomenon of the nut and the bolt in the installation process is prevented, the false torque phenomenon caused by the seizing in the installation process is prevented, and safety accidents are avoided.

Description

Technical Field

[0001] This invention relates to the field of nut processing technology, and in particular to a processing method for a flange nut with a built-in safety function. Background Technology

[0002] The flange nut with built-in safety function consists of a flange part, a hexagonal wrench part, a part with a safety groove, a threaded part, and a closing part (see...). Figure 1 The self-locking nut is used to connect the mounting bolt to the bolt by tightening, and achieves the self-locking function. It is often used in some high-temperature and high-strength connection parts in aviation, aerospace, ships, high-speed rail and other industries. It has high yield strength, endurance strength and creep strength, and has good processing plasticity and locking performance, which facilitates quick installation and disassembly. Currently, such parts are widely used in aircraft engine components and flight control systems. However, hexagonal flange nuts made of ordinary materials have a maximum operating temperature of no more than 250°C, can only be used 100 times, are easily damaged, and are inconvenient to replace. They also pose some hidden dangers during actual installation and cannot meet the heat requirements of aircraft engines and flight control systems during use. Therefore, hexagonal flange nuts used on aircraft engines and flight control systems are mostly made of high-temperature alloys, which can meet the high-temperature requirements of aircraft engines and flight control systems (operating temperature can reach up to 650°C) and can be used up to 1000 times. However, high-temperature alloys have characteristics such as high alloying degree, extremely poor thermal conductivity, high cutting temperature, large cutting force, and many hard particles. When using traditional turning and upsetting methods to process hexagonal flange nuts of high-temperature alloys, there are disadvantages such as low processing efficiency, high labor costs, severe tool wear, high tool consumption, poor product consistency, high processing costs, and unstable locking performance. Summary of the Invention

[0003] To address the aforementioned problems, the present invention aims to provide a processing method for flange nuts with a built-in safety function. This processing method overcomes the shortcomings of traditional processing methods, such as low processing efficiency, severe tool wear, high processing cost, and unstable locking performance.

[0004] The objective of this invention is achieved through the following technical solutions:

[0005] A method for machining a flange nut with a built-in safety feature includes the following steps:

[0006] S1. Material preparation: Prepare high-temperature alloy materials.

[0007] S2. Rough turning: Turning out the blank part according to the process requirements.

[0008] S3. Lubrication: Copper plating is applied to the outside of the blank for lubrication.

[0009] S4. Hot upsetting: After heating the blank, it is transferred to the punch press by a robot for hot upsetting.

[0010] S5. Heat treatment: The parts obtained after hot upsetting are put into the furnace, and after vacuuming, the temperature is raised to 850±10℃ at a rate of 15~20℃ / min and held for 25min~35min. Then, the temperature is raised to 1040~1080℃ for 20min~25min and held for 60min~90min. After the holding time is completed, the parts are transferred to the cold chamber for rapid cooling.

[0011] S6. Finish turning: Drill threaded holes and chamfer on the parts according to process requirements.

[0012] S7. Tapping: Use a special tap to tap the thread in three stages.

[0013] S8. Wire EDM: Cut six grooves evenly at the head of the part.

[0014] S9. Deburring: Remove burrs from parts.

[0015] S10. Mid-term inspection: Check whether the dimensions meet the requirements and perform subsequent finishing processing;

[0016] S11. Closure: A special closure fixture is used for tapered closure.

[0017] S12. Aging treatment: Solution treatment temperature 900±10℃, time 60min, oil cooling; aging temperature 710±10℃, time 16h, air cooling. Afterwards, sandblasting, flaw detection, and inspection (comprehensive inspection) are performed sequentially to obtain qualified products.

[0018] The beneficial effects of this invention are as follows:

[0019] 1. The flange nut with built-in safety function is made of hot forged bar stock. The mold ensures the effective distance of the hexagonal wrench and the dimensions of the flange face.

[0020] 2. The use of a robotic arm effectively controls the transfer time to within 2 seconds, allowing the bar stock to be quickly upset after heating, avoiding overheating.

[0021] 3. The use of CNC precision machining equipment controls the consistency of dimensions, improves production efficiency, ensures product dimensions, and makes the quality of parts stable.

[0022] 4. By using a special conical closing mold and hydraulic equipment to close the locking part, the consistency of the closing size is ensured and the stability of the locking performance is guaranteed.

[0023] 5. The surface treatment uses copper plating on the internal thread to prevent the nuts and bolts from seizing during installation; it effectively prevents false torque caused by seizing during installation and avoids safety accidents. Attached Figure Description

[0024] The present invention will now be described in further detail with reference to the accompanying drawings.

[0025] Figure 1 This is a schematic diagram of the structure of the flange nut with built-in safety function described in this invention;

[0026] Figure 2 This is a dimensional diagram of the flange nut with built-in safety function described in this invention, located in the groove before the opening is closed.

[0027] Figure 3 This is a dimensional diagram of the flange nut with built-in safety function described in this invention in the groove after closing;

[0028] Figure 4 This is a schematic diagram of the closing tooling of the present invention. Detailed Implementation

[0029] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The described embodiments are merely 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.

[0030] Example:

[0031] This embodiment provides a method for processing flange nuts with built-in safety features, including the following steps:

[0032] S1. Material Preparation: GH2132 (A286) high-temperature alloy bars are selected as raw materials, and cold-drawn, solution-treated, and polished. This material is a nickel-based high-temperature alloy strengthened by "γ" phase precipitation, possessing good resistance to gas corrosion, high yield strength and fatigue performance, good processability, and stable microstructure. This material is widely used in aero-engine components, with operating temperatures up to 650℃.

[0033] S2. Rough turning: Turning out the blank part according to the process requirements.

[0034] S3. Lubrication: Copper is plated on the outside of the blank for lubrication. The purpose is to prevent the surface of the product from being scratched during the warm forging process.

[0035] S4. Warm / Hot Upsetting: The blank is heated for about 10 seconds, with the heating temperature reaching approximately 850℃ (this process uses a constant temperature control system to maintain the temperature at around 850℃, effectively protecting the material's crystal structure from damage, resulting in finer grains and preventing overheating or burning of the product's metallographic structure). Then, a robotic arm transfers the blank to the punch press for hot upsetting within 2 seconds (to ensure the quality of the hot upsetting, an infrared thermometer is used in conjunction with an automatic feeding device on the punch press. Firstly, the automatic feeding device eliminates inconsistencies in transfer time caused by uncertainties in manual operation, ensuring that all parameters during hot upsetting are unaffected by human intervention and guaranteeing consistency in processing parameters for each part. Secondly, the infrared thermometer dynamically monitors temperature changes during the upsetting process).

[0036] S5. Heat Treatment: After hot upsetting, the parts are placed in a furnace (heat treatment furnace). After evacuating the furnace, the temperature is increased to 850±10℃ at a rate of 15-20℃ / min and held for 25-35 minutes. Then, the temperature is increased to 1040-1080℃ for 20-25 minutes and held for 60-90 minutes. After holding, the parts are transferred to a cold chamber and rapidly cooled with argon gas at a pressure of 800-1000 mbar. Alternatively, oil cooling can be used for rapid cooling in the cold chamber. Because the supporting surface of the product is relatively thin, the solution treatment process is moved to this step. This eliminates internal stress, achieves a grain size of 4-5, and prevents deformation of the supporting surface and cracking at the edges during subsequent processing.

[0037] S6. Finish machining: Drill threaded pilot holes on the parts according to process requirements and chamfer them; ensure that the perpendicularity between the threaded pilot holes and the flange part is ≤0.1m.

[0038] S7. Tapping: Use a special tap to tap the thread in three stages to ensure that the perpendicularity of the thread to the support plate is ≤0.1mm.

[0039] S8. Wire EDM: Six grooves are evenly cut at the head of the part (e.g., ...). Figure 2 As shown, the shape of the groove directly affects the locking performance. Groove dimensions before closing: B1, B2, groove angle θ.

[0040] S9. Deburring: Remove burrs from parts to ensure that the threads pass through the correct direction.

[0041] S10. Mid-term inspection: Check whether the dimensions meet the requirements and perform subsequent finishing processing.

[0042] S11. Finishing: As shown in the example... Figure 4 The special finishing tool shown performs tapered finishing (e.g.) Figure 3 (As shown). Dimensions of the groove after closing: B3.

[0043] S12. Aging Treatment (Secondary Heat Treatment): After solution treatment, the parts are placed at a higher temperature (at the aging temperature) or kept at room temperature to maintain their properties and shape. Solution temperature: 900±10℃, time: 60min, oil cooling; Aging temperature: 710±10℃, time: 16h, air cooling; The performance HRC of the parts reaches 29~36.

[0044] S13. Sandblasting: Sandblasting removes the oxide layer.

[0045] S14. Flaw detection: Detecting for defects such as cracks.

[0046] S15. Inspection: Perform dimensional and visual inspections according to product requirements, and submit for performance testing. Room temperature locking performance: Apply an installation torque of 4.068 N·m for each cycle. The maximum tightening torque is 2 N·m for the first tightening and a minimum tightening torque of 0.25 N·m for the fifteenth tightening.

[0047] Other aspects of this invention that are not detailed herein are all conventional techniques known to those skilled in the art.

[0048] It should be noted that the terms “comprising,” “including,” or any other variations are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0049] The scope of protection of this invention is not limited to the technical solutions disclosed in the specific embodiments. Any modifications, equivalent substitutions, improvements, etc., made to the above embodiments based on the technical essence of this invention shall fall within the scope of protection of this invention.

Claims

1. A method for processing a flange nut with a built-in safety function, characterized in that, Includes the following steps: S1. Material preparation: Prepare high-temperature alloy materials, wherein the material is GH2132 high-temperature alloy bar stock; S2. Rough turning: Turning the blank part according to the process requirements; S3. Lubrication: Copper plating is applied to the outside of the blank for lubrication; S4. Warm / Hot Upsetting: After heating the blank, a robot is used to transfer it to the punch press for hot upsetting; before hot upsetting, the blank is heated for 10 seconds and the heating temperature is controlled at 850℃; after heating, the blank is transferred to the punch press for hot upsetting within 2 seconds. S5. Heat treatment: After hot upsetting, the parts are placed in the furnace, and after vacuuming, the temperature is raised to 850±10℃ at a rate of 15-20℃ / min and held for 25min-35min. Then, the temperature is raised to 1040-1080℃ for 20min-25min and held for 60min-90min. After the holding period, the parts are transferred to the cold chamber and rapidly cooled with argon gas at a pressure of 800-1000mbar. S6. Finish machining: Drill threaded holes and chamfer on the parts according to process requirements; during finish machining, ensure that the perpendicularity between the threaded holes and the flange portion is ≤0.1mm; S7. Tapping: Use a special tap to tap the thread in three stages; when tapping, ensure that the perpendicularity of the thread to the support plate is ≤0.1mm; S8. Wire EDM: Cut six grooves evenly at the head of the part; S9. Deburring: Removing burrs from parts; S10. Mid-term inspection: Check whether the dimensions meet the requirements and perform subsequent finishing processing; S11. Closure: A special closure fixture is used for tapered closure; S12. Aging treatment: Solution treatment temperature 900±10℃, time 60min, oil cooling; Aging temperature 710±10℃, time 16h, air cooling; After aging treatment, the HRC of the part is 29-36. S13. Sandblasting: Sandblasting removes the oxide layer; S14. Flaw detection: Inspecting for defects such as cracks; S15. Inspection: Perform dimensional and appearance inspections and submit performance tests according to product requirements.

2. The processing method of the flange nut with built-in safety function according to claim 1, characterized in that... In step S5, after the heat preservation is completed, the part is transferred to the cooling chamber and rapidly cooled by oil cooling.

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