Integrated precision forging production process for steel forks

Abstract

The invention relates to the technical field of metal plastic processing, in particular to a steel fork integrated precision forging production process which comprises the following steps: (1) blank preparation: cutting an integrated steel fork blank comprising fork trousers, fork beams and fork teeth from a spring steel plate by adopting a laser cutting technology; (2) tooth dividing and pre-forming are conducted, specifically, the integrated blank is heated, then tooth dividing and pre-forming are synchronously completed in one stroke of a pressing machine through a composite die, tooth dividing refers to that the blank is separated into a plurality of fork teeth, and pre-forming refers to that tooth roots are bent; (3) roll forging and shaping: heating the blank subjected to tooth division pre-forming, and then carrying out multi-pass roll forging through a multi-groove roll forging machine to enable the prongs to form vertical elliptical sections; (4) forked trousers rolling and tooth part fine bending: carrying out local induction heating on the forked trousers part, rolling the forked trousers by using an edge rolling die, and precisely bending the tooth part by using a fine bending die; and (5) heat treatment: quenching and tempering the product to obtain the required mechanical property.

Description

Technical Field

[0001] This invention belongs to the category of advanced manufacturing processes in the field of metal plastic processing technology, specifically relating to an integrated production process for steel forks based on the principle of precision forging. Background Technology

[0002] As an indispensable hand tool in agriculture, horticulture, and material handling, the quality of steel forks directly affects users' work efficiency, operating experience, and labor intensity. A high-quality steel fork should possess characteristics such as high tooth strength, good overall toughness, regular tooth shape, comfortable grip, and corrosion resistance and durability. However, for a long time, the manufacturing process of steel forks has largely constrained further improvements in their performance and optimization of costs.

[0003] Currently, the mainstream steel fork manufacturing processes at home and abroad can be mainly categorized into two types: traditional split welding process and the initially developed integrated forging process.

[0004] Traditional modular welding is a relatively outdated production method. This process involves separately cutting, forging, or machining the various components of the steel fork, including the fork sleeves (or "fork covers") connecting the handle, the fork beam (the main body), and the fork teeth that perform specific functions. These components are then joined together by welding (usually arc welding or gas shielded welding). This process has several inherent drawbacks: First, the welding process creates heat-affected zones at the joints, inevitably introducing stress concentration points. During use, especially under alternating or impact loads, these areas are highly susceptible to fatigue cracking, leading to premature fracture at the fork sleeve / fork beam connection or at the tooth root, severely impacting product lifespan and operational safety. Second, because it involves separate manufacturing and subsequent assembly, the spacing, parallelism, and tooth profile consistency between the fork teeth are difficult to precisely control, often resulting in visible deviations. This inconsistency leads to uneven stress on the fork when inserting material; some teeth may bear excessive loads while others are underutilized, reducing work efficiency and affecting the user experience. Furthermore, after welding, weld spatter and weld beads result in a rough and uneven product surface, requiring additional post-processing steps such as grinding and polishing, which increases labor and production costs. More importantly, welding essentially disrupts the continuous flow grain structure of the metal material, forming a casting structure at the weld that differs significantly from the base material. This leads to a significant decrease in the overall mechanical properties of the product, particularly its impact toughness and fatigue strength, compared to a complete forging.

[0005] To overcome the drawbacks of separate welding, the industry has begun exploring integrated forging processes. For example, Chinese patent CN114632832B proposes a technical solution using laser cutting combined with a tooth-splitting mold. This solution uses a laser to cut a toothed, integrated blank from a single steel plate, and then uses a mold for tooth splitting and forming, thus avoiding the welding process and theoretically improving the overall integrity of the product. However, these existing integrated forging processes still have many shortcomings in practice that require improvement. First, the production processes are relatively dispersed. Key steps such as tooth splitting, rounding, and bending often need to be completed at separate workstations, meaning that the blank needs to undergo repeated heating and mold changes. Frequent heating not only leads to huge energy consumption but also slows down the production pace and reduces efficiency. Furthermore, repeated heating can cause excessive oxidation and decarburization of the steel surface, affecting surface quality. Second, for components like fork teeth with a large length-to-width ratio, controlling the forming accuracy, including the straightness of the teeth, the consistency of the cross-sectional shape, and the roundness of the tooth tips, is quite difficult. Relying on multiple simple functional molds for repeated forming results in significant accumulated errors, making it difficult to guarantee high consistency in product size and shape during mass production. Thirdly, to achieve the aforementioned dispersed processes, multiple dedicated presses, molds, and auxiliary equipment are required, leading to high initial equipment investment costs and large production line footprints, posing a significant barrier to entry for small and medium-sized enterprises. Fourthly, existing processes still have room for improvement in material utilization; billet design often fails to fully consider how to maximize the use of sheet metal.

[0006] In conclusion, neither traditional split welding nor the existing, still imperfect, integrated forging process can achieve the optimal balance between efficiency, cost, quality, and environmental protection, and cannot fully meet the urgent needs of modern industry for high-performance, low-cost, energy-saving, and environmentally friendly manufacturing technologies. Summary of the Invention

[0007] The core objective of this invention is to overcome the prominent technical challenges in existing steel fork manufacturing processes, such as complex procedures, high energy consumption, insufficient product strength, poor precision consistency, and high mold costs. To this end, this invention provides a novel integrated precision forging manufacturing process for steel forks. The core idea of ​​this process lies in its high degree of integration, creatively combining key steps such as laser-cut blank preparation, simultaneous tooth division and pre-forming with composite molds, and multi-groove roll forging precision rounding and shaping into a compact and continuous process flow.

[0008] The technical solution adopted by this invention to solve its technical problem is: a precision forging production process for integrated steel forks, comprising the following steps. (1) Blank preparation: Laser cutting technology is used to cut an integrated steel fork blank containing fork shank, fork beam and fork teeth from spring steel plate; (2) Splitting and preforming: The integrated blank is heated, and then the tooth splitting and preforming are completed simultaneously in one stroke of the press using a composite mold. Splitting is to separate the blank into multiple fork teeth, and preforming is to bend the tooth roots. (3) Roll forging: The preformed billet is heated and then rolled multiple times through a multi-groove roll forging machine to form a vertical elliptical cross section for the fork teeth; (4) Rolling and precision bending of the fork pants: After local induction heating of the fork pants, roll the fork pants using a rolling die, and precisely bend the teeth using a precision bending die. (5) Heat treatment: Quenching and tempering the product to obtain the required mechanical properties; (6) Surface treatment: electrostatic spraying is performed on the product to form an anti-corrosion coating.

[0009] In the further described integrated precision forging production process of steel forks, the spring steel plate in step (1) is 65Mn or 60Si2Mn spring steel with a thickness of 8-12mm.

[0010] In the further described steel fork integrated precision forging production process, step (1) adopts tooth cross layout technology for layout to improve material utilization.

[0011] In the further described integrated precision forging process for steel forks, the heating temperature in step (2) is 1100-1200℃.

[0012] In the further described steel fork integrated precision forging production process, the press in step (2) is a 1000-ton hydraulic press with a holding pressure of 800-1000 tons and a holding time of 3-5 seconds.

[0013] In the further described steel fork integrated precision forging production process, the rolling heating temperature in step (3) is 880-920℃, the rolling speed is 2-3 m / min, and it is rolled 3-4 times.

[0014] The integrated precision forging production process of steel forks further describes that the multi-groove roll forging machine in step (3) has four sets of groove types, including circular groove, variable cross-section elliptical groove, variable cross-section circular groove and final elliptical forming groove.

[0015] In the further described integrated precision forging production process of steel forks, the local induction heating temperature in step (4) is 890-910℃, and the inner diameter of the fork roll after rolling is Φ35mm±0.5mm.

[0016] In the further described precision forging process for steel forks, the quenching temperature in step (5) is 840-860℃, the tempering temperature is 340-360℃, and the tempering time is not less than 1.5 hours.

[0017] In the further described steel fork integrated precision forging production process, the electrostatic spray coating thickness in step (6) is 60-80μm, the curing temperature is 210-230℃, and the curing time is 15 minutes.

[0018] The beneficial effects of this invention are: 1. Significantly Improved Production Efficiency: By integrating the two key processes of tooth splitting and pre-forming into a single heating and pressing stroke using composite mold technology, 2-3 intermediate handling, heating, and mold-changing processes are directly reduced, shortening the entire production cycle by more than 40%. The production line cycle time is faster, and daily output can be increased by 50% compared to traditional integrated forging processes, better meeting the needs of large-volume market orders.

[0019] 2. Significantly reduced energy consumption: Traditional processes often require 7-8 or even more heating steps, while this invention, through process integration and optimization, reduces the main heating steps to 3-4 (one main heating after billet preparation, one possible supplementary heating before roll forging, and local heating during forklift rolling). This reduces energy consumption per unit product by 30%-35%, not only lowering production costs but also meeting the stringent requirements of current green manufacturing and sustainable development.

[0020] 3. Superior Product Performance: Integrated forging fundamentally eliminates weak weld zones, resulting in a complete forged structure with strong integrity. Combined with the vertical elliptical cross-section design of the teeth, the streamlined fibrous structure from roll forging, and optimized heat treatment, the load-bearing capacity (single tooth load-bearing capacity) of the steel fork is increased by more than 25% compared to traditional welded products, fatigue life (under alternating loads) is extended by more than 3 times, and product reliability is significantly enhanced.

[0021] 4. High Precision Consistency: From high-precision laser cutting to synchronous and precise tooth pre-forming of composite molds, and then to stable shaping through multi-groove roll forging, the precision of the entire process is systematically controlled. The tolerances of key dimensions such as tooth pitch error, tooth profile size, and fork inner diameter of batch products can be stably controlled within ±0.3mm, making it very suitable for modern, automated mass production, ensuring stable and reliable product quality.

[0022] 5. Significant cost advantages: On the one hand, the cross-layout layout technology for the teeth increases material utilization by approximately 10%, directly reducing raw material costs. On the other hand, the reduction in the number of molds (for example, composite molds replace multiple sets of molds such as the original toothed molds and pre-bending molds) reduces the total mold investment cost by approximately 50%. Coupled with savings in energy consumption, labor, and site costs, the overall production cost can be reduced by more than 20% compared to existing processes, resulting in strong product market competitiveness.

[0023] 6. Excellent process flexibility and adaptability: The process described in this invention is not rigid or fixed; its core lies in modular mold design and adjustable process parameters. By adjusting the blank thickness, mold groove details, heat treatment parameters, etc., steel fork products with different numbers of teeth, different specifications, and different strength requirements can be easily produced. It can even be extended to other multi-toothed tools such as rakes and forks, demonstrating excellent process flexibility and broad application prospects. Attached Figure Description

[0024] The present invention will be further described below with reference to the embodiments and examples.

[0025] Figure 1 This is a comparative analysis chart of existing steel fork manufacturing processes.

[0026] Figure 2 This is a comparison chart of the performance of the present invention and traditional processes.

[0027] Figure 3 This is a comparison chart of process parameters for the examples. Detailed Implementation

[0028] The following section, in conjunction with process flow diagrams, performance comparison charts, and specific embodiments, provides a more detailed and in-depth description of the high-efficiency, energy-saving integrated precision forging production process of the present invention. This section aims to enable those skilled in the art to fully understand the technical solution of the present invention and master its specific implementation methods. It should be noted that the embodiments and examples described below are further explanations of the present invention, rather than limitations on the scope of protection of the present invention. Under the guidance of the principles of the present invention, those skilled in the art can also make some appropriate adjustments and improvements, all of which fall within the scope of protection of the present invention.

[0029] Detailed explanation of the core process steps of this invention: (1) Precision preparation of billet: Equipment selection: High-power fiber laser cutting machines are preferred, with a power recommended between 2000W and 6000W to ensure fast and high-quality cutting of 8-12mm thick spring steel plates. The CNC platform accuracy should ensure a positioning error of less than 0.1mm.

[0030] Material requirements: 65Mn or 60Si2Mn spring steel is primarily recommended. Its chemical composition and mechanical properties must comply with relevant national standards such as GB / T1222-2016 "Spring Steel". The plate surface should be smooth and free from severe oxide scale, rust, and other defects.

[0031] Layout Design and CAD / CAM: Professional CAD / CAM software is used for billet design and layout optimization. The core technology is the application of "toothed cross-layout technology," which uses computer algorithms to automatically optimize the staggered positions of the teeth on two adjacent billets, maximizing the utilization of the sheet metal area. The software simultaneously generates efficient laser cutting paths, ensuring cutting speed and cut quality.

[0032] Cutting quality control: During the cutting process, process parameters (such as cutting speed, auxiliary gas pressure, focal point position, etc.) need to be optimized to obtain a cut surface with good perpendicularity, less slag, and a narrow heat-affected zone. After cutting, the blank tooth spacing error needs to be randomly checked to ensure that it meets the design requirement of ±0.3mm.

[0033] (2) Tooth splitting and preforming composite process: Heating system: A medium-frequency induction heating furnace is used, which has fast heating speed, high efficiency, and low oxidation. Temperature control accuracy must be within ±20℃. The relationship between holding time (t) and billet thickness (h) can be estimated using the formula t=kh(min), where k takes a value of 1.0~1.5, which can be finely adjusted according to the billet material and size.

[0034] Composite mold design and manufacturing: Structure: The mold needs to achieve sequential or coordinated actions of tooth splitting and preforming. This can be achieved by fixing the tooth splitting module and having the preforming module move accordingly; alternatively, a special structure can be used to achieve continuous action in a single stroke. The main body of the mold is made of H13 material, while key wear parts such as the tooth splitting rack can be made of high-performance cemented carbide or undergo reinforced surface treatment.

[0035] Split rack design: The wedge angle and surface finish need to be optimized to reduce splitting resistance and wear. The clearance design should be reasonable to prevent material jamming.

[0036] Preformed module design: The radius of curvature and angle of the arc extrusion strip need to be calculated precisely to ensure that the bending angle (25°-30°) is accurate and the transition is smooth without sharp corner stress concentration.

[0037] Press and process parameters: Select a hydraulic press with a capacity of 1000 tons or more to ensure sufficient forming force and stability. The holding pressure is usually in the range of 800-1000 tons, and the holding time is 3-5 seconds to allow the metal to undergo sufficient plastic deformation and stabilize its shape.

[0038] (4) Roll forging and precision shaping: Heating: The preform is supplemented with heating to 900℃±15℃ using induction heating or a box furnace. The temperature should not be too high to prevent excessive oxidation and grain growth.

[0039] (5) Roll forging die system: Channel Sequence Design: The shape variations of the four channels need to be carefully designed based on the theory of metal plastic forming and finite element simulation analysis to ensure smooth metal flow, full filling, and no defects such as folds or cracks. The design of the variable cross-section channels aims to guide the metal from the initial shape to the final elliptical cross-section gradually and smoothly.

[0040] Die material and processing: Roll forging dies are subjected to thermal cycling and friction, so die steel with good heat resistance, such as H11 and H13, must be selected. High-precision CNC engraving and heat treatment are also used to ensure the dimensional accuracy of the groove and the surface hardness.

[0041] Roll forging process: The rolling speed (2-3m / min) and the number of passes (3-4 times) need to be matched to ensure that the deformation amount of each pass is reasonable, so as to ensure the forming effect and avoid equipment overload or product defects.

[0042] (6) Rolling and fine bending of the trousers: Localized heating: Using a high-frequency or medium-frequency induction coil, precisely aimed at the trouser area, it rapidly heats to 900℃±10℃. An infrared thermometer monitors the temperature in real time.

[0043] Rolling mold: The mold design must ensure smooth material flow during the rolling process, resulting in a well-rounded cylinder with tight joints. The inner diameter is precisely guaranteed by the mold cavity dimensions.

[0044] Precision bending die for teeth: Utilizing a three-dimensional curved surface die, the shape is CNC machined based on an ideal tooth profile curve. Executed on a precision gear bending machine (such as a CNC hydraulic gear bending machine), it allows for precise control of the bending radius and angle, ensuring the consistency of curvature in multi-tooth products.

[0045] (7) Heat treatment and surface treatment: Heat treatment process: A continuous controlled atmosphere quenching and tempering production line is recommended. The quenching temperature is approximately 850℃, and the holding time depends on the product thickness; oil cooling is used. The tempering temperature is approximately 350℃, and the time is no less than 1.5 hours to ensure sufficient elimination of internal stress and obtain a stable tempered martensite structure. Hardness testing is performed according to GB / T230.1 standard.

[0046] Surface treatment process: Pretreatment includes degreasing, rust removal, and phosphating to improve coating adhesion. For electrostatic spraying of epoxy powder, parameters such as voltage and spray gun distance need to be optimized to ensure uniform coating. Curing oven temperature and time (e.g., 220℃, 15min) must be strictly controlled to ensure complete cross-linking and curing of the coating. Salt spray testing is conducted according to GB / T10125 standard to evaluate corrosion resistance.

[0047] The following two specific embodiments further illustrate the implementation process and technical effects of the present invention.

[0048] Example 1: Production of a Six-Tooth Gardening Fork This embodiment uses a common six-tooth garden fork as the target product to demonstrate the complete application of the present invention in detail.

[0049] (1) Material preparation: 65Mn spring steel plate conforming to GB / T1222-2016 standard, with a thickness of 10mm, was selected. A 3000W high-performance fiber laser cutting machine was used to cut the plate into integrated blanks on a CNC platform. The dimensions of a single blank were approximately 400mm (length) × 200mm (width), containing six optimized compact fork teeth. During computer nesting, a tooth cross-layout algorithm was strictly applied to ensure that the tooth gaps of adjacent blanks were perfectly complementary. According to actual calculations, the material utilization rate of the plate under this layout reached 87.5%, which is about 12 percentage points higher than the traditional parallel nesting method, resulting in significant material savings.

[0050] (2) Tooth separation and preforming: The cut billet is fed into a medium-frequency induction heating furnace. The heating temperature is set to 1150℃, and considering the thickness of 10mm, the holding time is set to 12 minutes (calculated at 1.2min / mm). After the billet is heated evenly, it is quickly removed by a robotic arm and accurately placed in the composite mold working area of ​​a 1000-ton hydraulic press. The tooth separation module of this composite mold uses advanced hard alloy coating technology for its four core tooth strips, which have extremely high surface hardness and excellent wear resistance. It is expected that the mold life can be increased by more than 30% compared with uncoated H13 steel. When the press is started, the tooth strips first embed into the billet, completing the clear separation of the six teeth. Then, in the later stage of the press stroke, the arc-shaped extrusion strip of the preforming module simultaneously performs a bending operation on the six tooth roots, with the bending angle set at 28°. During this process, the holding pressure is maintained at 900 tons, and the holding time is 4 seconds. The entire process of tooth splitting and preforming is completed in one go, replacing the traditional process that requires two separate heating cycles and the use of two different molds, resulting in a significant improvement in efficiency.

[0051] (3) Roll Forging and Rounding: The pre-bent billet with teeth is transferred to another heating device and heated to 900℃ for uniform temperature before roll forging. Subsequently, the billet is fed into a four-groove continuous roll forging mill. The roll forging linear speed is set to 2.5 m / min. The billet passes through a circular groove, a variable cross-section elliptical groove, a variable cross-section circular groove, and a final elliptical forming groove in sequence, for a total of four rolling passes. The design of the variable cross-section elliptical groove was determined through repeated optimization using computer finite element analysis (FEA), which can effectively distribute the fiber flow of the tooth metal along the long axis of the tooth and the expected stress direction. Metallographic analysis and mechanical testing show that this optimized streamline distribution increases the bending load capacity of the tooth by more than 25% compared to ordinary round teeth.

[0052] (4) Fork fork rolling and precision bending: A high-frequency induction heating device with an output power of 5kW, equipped with a dedicated contour coil, is used to rapidly and locally heat only the fork fork area, with the temperature strictly controlled within the range of approximately 900℃±10℃. Then, the fork fork is rolled using a dedicated rolling die on a 500-ton precision punch press. The inner diameter of the rolled fork fork is sampled and tested, and is stably controlled within the design requirement of Φ35mm±0.5mm. For the final bending of the teeth, a CNC hydraulic tooth bending machine is used in conjunction with a high-precision three-dimensional curved surface die. The bending radius is set to R350mm, which is calculated and selected based on the length ratio of the six teeth and ergonomic principles. The CNC system ensures the consistency of the bending arc and height of the six teeth.

[0053] (5) Heat Treatment and Surface Treatment: The product enters a continuous controlled atmosphere heat treatment production line. First, it is oil quenched at 850℃, followed by tempering at 350℃ for 2 hours. After tempering, the hardness of the product is sampled and tested. The results are stable within the ideal range of HRC42-44, achieving the best balance between strength and toughness required for garden steel forks. In the surface treatment stage, after pretreatment, environmentally friendly epoxy powder is used for electrostatic spraying, with a target coating thickness of 70μm. The sprayed product is baked in a curing oven at 220℃ for 15 minutes to allow the powder to fully melt, level, cross-link and cure, forming a uniform, dense, glossy and highly adhesive anti-corrosion protective layer.

[0054] (6) Quality Inspection and Results: A comprehensive quality inspection was conducted on 100 six-tooth gardening steel forks produced in batches according to the above process. The main results are as follows: ① Dimensional accuracy: The tooth pitch error of all sampled products was within 0.28mm, which is far better than the design requirement of ±0.3mm.

[0055] ②Mechanical properties: The static load bearing capacity of a single tooth is no less than 280kg, which far exceeds the requirements of ordinary horticultural operations.

[0056] ③ Fatigue life: Simulating actual operating conditions, fatigue tests were conducted under an alternating load of 150kg. All tested samples had a lifespan exceeding 38,000 cycles, demonstrating excellent durability.

[0057] ④ Corrosion resistance: After a 240-hour neutral salt spray test according to the standard, the coating surface showed no blistering, peeling, or substrate corrosion, demonstrating excellent corrosion resistance.

[0058] Based on the above test data, the six-tooth gardening steel fork produced in this embodiment has fully met or even exceeded the performance standards of similar products from internationally renowned tool manufacturers (such as Ames TrueTemper in the United States).

[0059] Example 2: Adaptive Adjustment of a Four-Toothed Agricultural Steel Fork This embodiment, designed for four-pronged agricultural forks requiring higher strength and wear resistance (commonly used in heavy-duty tillage), demonstrates the flexibility and adjustability of the process described in this invention. While largely following the process flow of Embodiment 1, only a few key parameters are adjusted: Blank adjustment: To increase overall rigidity, 12mm thick 65Mn spring steel plates are selected for laser cutting.

[0060] Process Enhancement: After the roll forging and rounding process, an additional "cold finishing" process is added. Using a finishing die at room temperature, the tooth tip is lightly calibrated and extruded, further improving the dimensional accuracy and surface finish of the teeth (up to Ra1.6μm or higher), and reducing frictional resistance during use.

[0061] Heat treatment adjustment: To meet heavy load requirements, the heat treatment process parameters were adjusted, and the tempering temperature was appropriately reduced to adjust the hardness range of the final product to HRC44-46, thereby obtaining higher hardness and wear resistance while ensuring a certain level of toughness.

[0062] By adjusting the parameters as described above, four-pronged agricultural steel forks that meet higher strength requirements can be successfully produced without changing the core process and equipment. This fully demonstrates that the process described in this invention is not static; its modular and parameterized design concept gives it good adaptability and scalability, enabling it to respond quickly to diverse market demands.

[0063] This invention, through systematic research, innovative design, and rigorous process verification, has deeply optimized and integrated the entire process of steel fork production. It has achieved key technological breakthroughs in core stages such as billet preparation, tooth pre-forming, and roll forging, particularly through the application of composite dies and the optimized design of the roll forging sequence, which have brought the advantages of integrated forging to a new level.

[0064] This technology has achieved breakthroughs in production efficiency, energy consumption, product quality, production costs, and environmental performance, providing a practical, efficient, and reliable technological path for the transformation and upgrading of the traditional hand tool manufacturing industry. With the increasing demands for intelligent, green, and high-end manufacturing in the global manufacturing sector, this technology is expected to become the standard process and mainstream direction for the production of steel forks and similar multi-toothed tools (such as rakes and fork shovels), powerfully driving technological progress and industrial upgrading across the entire industry.

Claims

1. A precision forging process for integrated steel forks, characterized in that: Includes the following steps (1) Blank preparation: Laser cutting technology is used to cut an integrated steel fork blank containing fork shank, fork beam and fork teeth from spring steel plate; (2) Splitting and preforming: The integrated blank is heated, and then the tooth splitting and preforming are completed simultaneously in one stroke of the press using a composite mold. Splitting is to separate the blank into multiple fork teeth, and preforming is to bend the tooth roots. (3) Roll forging: The preformed billet is heated and then rolled multiple times through a multi-groove roll forging machine to form a vertical elliptical cross section for the fork teeth; (4) Rolling and precision bending of the fork pants: After local induction heating of the fork pants, roll the fork pants using a rolling die, and precisely bend the teeth using a precision bending die. (5) Heat treatment: Quenching and tempering the product to obtain the required mechanical properties; (6) Surface treatment: electrostatic spraying is performed on the product to form an anti-corrosion coating.

2. The integrated precision forging production process for steel forks according to claim 1, characterized in that: The spring steel plate mentioned in step (1) is 65Mn or 60Si2Mn spring steel with a thickness of 8-12mm.

3. The integrated precision forging production process for steel forks according to claim 1, characterized in that: In step (1), a toothed cross layout technique is used for layout to improve material utilization.

4. The integrated precision forging production process for steel forks according to claim 1, characterized in that: The heating temperature in step (2) is 1100-1200℃.

5. The integrated precision forging production process for steel forks according to claim 1, characterized in that: The press mentioned in step (2) is a 1000-ton hydraulic press with a holding pressure of 800-1000 tons and a holding time of 3-5 seconds.

6. The integrated precision forging production process for steel forks according to claim 1, characterized in that: In step (3), the rolling heating temperature is 880-920℃, the rolling speed is 2-3 m / min, and the rolling process is repeated 3-4 times.

7. The integrated precision forging production process for steel forks according to claim 1, characterized in that: The multi-groove roll forging machine described in step (3) has four sets of groove types, including circular groove, variable cross-section elliptical groove, variable cross-section circular groove and final elliptical forming groove.

8. The integrated precision forging production process for steel forks according to claim 1, characterized in that: In step (4), the local induction heating temperature is 890-910℃, and the inner diameter of the fork trousers after rolling is Φ35mm±0.5mm.

9. The integrated precision forging production process for steel forks according to claim 1, characterized in that: In step (5), the quenching temperature is 840-860℃, the tempering temperature is 340-360℃, and the tempering time is not less than 1.5 hours.

10. The integrated precision forging production process for steel forks according to claim 1, characterized in that: In step (6), the electrostatic spray coating thickness is 60-80μm, the curing temperature is 210-230℃, and the curing time is 15 minutes.

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