Forming equipment and manufacturing process of high-brightness stainless steel plate

Abstract

The invention discloses forming equipment and a manufacturing process of a high-brightness stainless steel plate, relates to the technical field of punch forming machining, and aims to solve the technical problems of non-uniform lubrication, large lubricating oil loss, high mold maintenance cost and lack of a dynamic adjusting mechanism in a traditional lubricating scheme. Comprising a stamping device, a fixed workbench fixedly arranged on a workbench of the stamping device and a movable workbench arranged at the hydraulic end of the stamping device. The fixed workbench and the movable workbench are jointly provided with a forming die, and an oil pumping assembly connected to the forming die is arranged on the rear side of the stamping equipment. The forming die comprises a lower die body and an upper die body which are arranged on the fixed workbench and the movable workbench respectively. Through the combination of the Tesla valve type one-way flow control channel and the exposed radial bifurcated flow channel, it can be ensured that scratches and pollution are effectively avoided in the stamping process of the complex curved surface of the hub cover, and the highlight surface quality of the hub cover is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of stamping forming processing, and more specifically, to a forming device and manufacturing process for high-gloss stainless steel plates. Background Art

[0002] In the field of production and manufacturing of automotive stainless steel wheel hub covers, high gloss is an important quality indicator, which directly affects the appearance texture and market competitiveness of products. Currently, the wheel hub covers mainly adopt the stamping forming process, that is, relying on a press and a mold to apply an external force to a high-gloss stainless steel plate to cause plastic deformation to obtain the required shape. To reduce the friction between the mold and the stainless steel plate during stamping and avoid surface wear affecting the final high-gloss effect, the traditional process generally uses the method of applying lubricating oil to the mold for lubrication.

[0003] However, the existing lubrication solutions have significant defects: Firstly, the problem of uneven lubrication is prominent. Manual application or traditional spray lubrication is difficult to precisely control the distribution of lubricating oil. During the stamping of the complex curved surface of the wheel hub cover, areas such as the corners and edges of the mold often have scratches due to insufficient lubrication, resulting in the surface roughness Ra value rising from the ideal 0.1 to 0.3 or more, seriously affecting the subsequent polishing quality; while in areas such as the center of the mold, residual contamination is likely to occur due to the accumulation of lubricating oil, requiring additional cleaning processes, increasing production costs and processing time.

[0004] Secondly, the lubricating oil loss is serious. The traditional lubrication method cannot dynamically adjust the oil supply amount according to the stamping process. To ensure the lubrication effect, excessive oil supply is often used, resulting in a waste rate of lubricating oil as high as 40% - 50%. At the same time, the spilled lubricating oil volatilizes into the workshop environment, causing both resource waste and potential safety hazards.

[0005] Thirdly, the mold maintenance cost is high. Open lubrication makes the lubricating oil easily contact the air and oxidize to form sludge, which adheres to the mold surface and accelerates wear, shortening the service life of the mold by about 30%. Frequent maintenance and replacement further drive up production costs.

[0006] Fourthly, there is a lack of a dynamic adjustment mechanism. The existing process is difficult to accurately control the lubricating oil flow rate and oil film thickness according to the working condition parameters such as stamping speed, pressure, and mold temperature that change in real time, resulting in unstable lubrication effects and a high defective product rate.

[0007] In addition, the existing lubrication systems are not fully designed to consider the reflux and recycling of lubricating oil. The residual lubricating oil after a single stamping cannot be effectively recovered, not only causing waste but also potentially contaminating subsequent workpieces, limiting the improvement of production efficiency and product quality.

[0008] In view of this, we propose a forming device and manufacturing process for high-brightness stainless steel plates. Summary of the Invention

[0009] The purpose of the present invention is to provide a forming device and manufacturing process for high-brightness stainless steel plates, so as to solve the technical problems of uneven lubrication, large lubricating oil loss, high die maintenance cost, and lack of dynamic adjustment mechanism in traditional lubrication solutions.

[0010] To solve the above technical problems, the present invention provides the following technical solutions: A forming device for high-brightness stainless steel plates, including a stamping device, a fixed stationary workbench disposed at the upper workbench of the stamping device, and a movable workbench disposed at the hydraulic end of the stamping device; A forming die is jointly provided on the stationary workbench and the movable workbench, and a pump oil assembly connected to the forming die is disposed at the rear side of the stamping device; The forming die includes a lower die body and an upper die body respectively disposed on the stationary workbench and the movable workbench. A concave surface forming cavity for stamping and forming a concave surface on the stainless steel hub cap is machined at the top of the lower die body, and a convex surface forming cavity for stamping and forming a convex surface on the stainless steel hub cap is machined at the bottom of the upper die body. A stamping lubrication system distributed on the concave surface forming cavity and the convex surface forming cavity is jointly opened at the center inside the lower die body and the upper die body. When the lower die body and the upper die body are closed, the concave surface forming cavity and the convex surface forming cavity form a stamping closing forming cavity for realizing the stamping forming of the stainless steel hub cap; The stamping lubrication system spreads the lubricating oil to the die working surface through capillary action. The lubricating oil exposed in the stamping lubrication system is compressed by the closing pressure to generate a pressure gradient, so that the exposed lubricating oil is directionally released to the upper and lower surfaces of the stainless steel plate to form an oil film, and the pressure unloading causes the lubricating oil to flow back and replenish to form a dynamic lubrication cycle.

[0011] The present invention combines a Tesla valve type unidirectional flow control channel with an exposed radial bifurcated flow channel, uses capillary action and an oil-loving coating to uniformly diffuse the lubricating oil to the die working surface, and precisely controls the lubricating oil overflow position through a hydrophobic layer to form a uniform micro-protrusion oil trace. The oil trace height and oil film thickness can be accurately calculated to ensure that during the stamping process of the complex curved surface of the hub cap, the uniformity error of the surface oil film thickness is controlled within ±5%, and the surface roughness Ra value is stably maintained at 0.1 Hereinafter, scratches and contamination are effectively avoided, and the high-brightness surface quality of the hub cap is significantly improved.

[0012] Preferably, the stamping lubrication system includes two oil inlet through holes respectively opened at the centers of the lower die body and the upper die body, two Tesla valve type unidirectional flow control channels for realizing passive unidirectional flow control of lubricating oil, and two exposed radial bifurcated channels respectively arranged in an annular array on the surfaces of the concave forming cavity and the convex forming cavity. The two Tesla valve type unidirectional flow control channels are respectively arranged in an annular array in the lower die body and the upper die body, and the Tesla valve type unidirectional flow control channel is connected to the corresponding oil inlet through hole.

[0013] Preferably, the exposed radial bifurcated channel includes a groove-shaped channel and a plurality of groove-shaped bifurcated channels. One end of the groove-shaped channel is connected to the corresponding Tesla valve type unidirectional flow control channel, and the plurality of groove-shaped bifurcated channels are symmetrically distributed on both sides of the groove-shaped channel and are connected to the groove-shaped channel. The plurality of groove-shaped channels extend radially away from the Tesla valve type unidirectional flow control channel in equal proportion starting from the Tesla valve type unidirectional flow control channel.

[0014] Preferably, the inner walls of the groove-shaped channel and the groove-shaped bifurcated channels are magnetron sputtered with an oil-loving layer, and the non-channel areas on the inner walls of the concave forming cavity and the convex forming cavity are sprayed with a hydrophobic layer. The lubricating oil flowing in the groove-shaped channel and the groove-shaped bifurcated channels under the influence of capillary action forms groove oil storage, and the groove oil storage forms micro-convex platform oil traces for directional oil film release and reflux replenishment outside the groove-shaped channel and the groove-shaped bifurcated channels under the influence of the hydrophobic layer.

[0015] Preferably, a round hole forming boss for stamping the assembly hole on the stainless steel hub cap is constructed at the center of the concave forming cavity, and a conveying interface connected to the corresponding oil inlet through hole is installed on one side of the lower die body and the upper die body.

[0016] Preferably, the oil pumping assembly includes a cold oil pump arranged on the back of the stamping equipment and an oil inlet arranged on the cold oil pump. The two oil outlet ends of the cold oil pump are respectively connected to a lower die oil delivery hose and an upper die oil delivery hose, and the lower die oil delivery hose and the upper die oil delivery hose are respectively connected to the corresponding conveying interfaces.

[0017] A manufacturing process of a stainless steel hub cap based on a high-brightness stainless steel plate includes the following steps: S1: Sheet and equipment preparation: Cut the high-brightness stainless steel plate into a suitable size and place it above the lower die body. Connect the oil outlet pipeline of the external oil storage equipment to the oil inlet, and control the cold oil pump through the stamping equipment to quantitatively deliver oil to the oil inlet through holes in the lower die body and the upper die body. S2: Lubricating oil pre-distribution: The lubricating oil flows into the Tesla valve type unidirectional flow control channel through the oil inlet through-hole, and then diffuses along the groove-shaped flow channel and the groove-shaped bifurcated flow channel by capillary action, and the lubricating oil is constrained in the flow channel by the oil-loving layer of the oil-loving coating on the inner wall; S3: Stamping forming and dynamic lubrication: The stamping equipment drives the moving workbench to drive the upper die body to move downwards to close the mold, forming a stamping and mold-closing forming cavity, and at the same time, the round hole forming boss punches out the assembly hole; During the mold-closing process, the cold oil pump continuously replenishes oil, and the lubricating oil forms a micro-boss oil trace at the edge of the flow channel under the action of the hydrophobic layer, and uses the one-way blocking characteristic of the Tesla valve type unidirectional flow control channel to make the micro-boss oil trace release directionally to form an oil film; S4: Pressure unloading and lubricating oil reflux: After stamping, the pressure is unloaded, and the lubricating oil flows back to the groove-shaped flow channel and the groove-shaped bifurcated flow channel under the action of surface tension and the hydrophobic layer, forming a decayed micro-boss oil trace; S5: Demolding and oil quantity replenishment: Separate the lower die body and the upper die body to take out the formed hub cap, calculate the lubricating oil loss, and replenish the lubricating oil through the cold oil pump to enter the next stamping cycle.

[0018] Preferably, in the step S3, the Tesla valve type unidirectional flow control channel adopts a three-stage bifurcated asymmetric contraction-expansion structure, the forward flow resistance is reduced by 50%, and the reverse flow attenuation rate ≥ 80%.

[0019] Preferably, in the step S5, the oil delivery flow rate of the cold oil pump is adjusted by using an adaptive fuzzy PID control algorithm, and the control formula is: , in the formula, is the flow error, is the error change rate, , , are the proportional, integral, and differential coefficients dynamically adjusted based on fuzzy rules.

[0020] Preferably, in the step S3, the height of the micro-boss oil trace is calculated by the formula , in the formula, is the volume of the overflowing lubricating oil, is the surface area of the flow channel edge, and the micro-boss oil trace generates a pressure gradient under the clamping pressure , according to the formula , in the formula, is the pressure applied by the mold during the mold-closing process, is the contact area between the mold and the plate.

[0021] Compared with the prior art, the beneficial effects of the present invention are: 1. By combining the Tesla valve type unidirectional flow control channel with the exposed radial bifurcated flow channel, the present invention uses capillary action and a lipophilic coating to evenly diffuse the lubricating oil to the working surface of the mold, and precisely controls the overflow position of the lubricating oil through a hydrophobic layer to form a uniform micro-protrusion oil trace. The height of the oil trace and the thickness of the oil film can be accurately calculated to ensure that during the stamping process of the complex curved surface of the hub cap, the uniformity error of the surface oil film thickness is controlled within ±5%, and the surface roughness Ra value is stably maintained at 0.1 Thereby, scratches and contamination can be effectively avoided, and the high-gloss surface quality of the hub cap can be significantly improved.

[0022] 2. The present invention realizes the dynamic recycling of lubricating oil. When the pressure is unloaded, the lubricating oil flows back to the groove-shaped flow channel under the action of surface tension and the coating, and the backflow coefficient reaches 0.6 - 0.8, reducing the waste of lubricating oil by more than 40% compared with the traditional process. At the same time, the cold oil pump uses an adaptive fuzzy PID control algorithm to adjust the oil delivery flow rate to match the stamping working condition requirements in real time, avoiding excessive oil supply, further reducing the lubricating oil usage cost, and the lubricating oil consumption for single-batch hub cap production can be reduced by 35% - 45%.

[0023] 3. The present invention also significantly reduces die wear through a uniform and stable lubricating effect. By precisely controlling the oil film thickness and pressure gradient, the dry friction between the die and the stainless steel plate is reduced, the wear amount of the key components of the die is reduced by more than 50%, and the service life is extended to 1.5 - 2 times that of the traditional die. In addition, the automatic dynamic adjustment function of the system can respond to changes in stamping speed, pressure, and temperature in real time to ensure a stable lubricating effect throughout the production cycle, reducing the product defective rate from 8% - 12% of the traditional process to below 3%, greatly improving production efficiency and product quality stability, and reducing the comprehensive production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0025] Figure 2 It is a schematic diagram of the overall back structure of the present invention.

[0026] Figure 3 It is a schematic diagram of the structure of a high-gloss stainless steel hub cap produced by stamping a high-gloss stainless steel plate with the forming equipment in the present invention.

[0027] Figure 4 It is a schematic diagram of the assembled state of the forming die and the oil pumping assembly in the present invention.

[0028] Figure 5 It is a schematic diagram of the structure of the lower die body in the present invention.

[0029] Figure 6 It is a schematic diagram of the structure of the upper die body in the present invention.

[0030] Figure 7 This is a partial structural cross-sectional view of the lower die body and the upper die body of the present invention in the mold-closed state.

[0031] Figure 8 This is a cross-sectional view of the lower die body of the present invention.

[0032] Figure 9 For the present invention Figure 8 An enlarged schematic view of the structure at position A in the present invention.

[0033] Figure 10 This is a distribution plan view of the stamping lubrication system in the concave forming cavity when the lower die body of the present invention is in a cross-sectional state.

[0034] Figure 11 This is a schematic diagram of the lubricating oil cross-section state in the exposed radial bifurcated flow channel of the lower die body of the present invention when it is in a partial structural cross-sectional state.

[0035] Explanation of the reference numerals in the figure: 1. Stamping equipment; 2. Fixed workbench; 3. Moving workbench; 4. Forming die; 401. Lower die body; 402. Upper die body; 403. Concave forming cavity; 404. Round hole forming boss; 405. Convex forming cavity; 406. Delivery interface; 407. Stamping mold-closed forming cavity; 5. High-gloss stainless steel hub cap; 501. Assembly hole; 6. Oil pumping assembly; 601. Cold oil pump; 602. Oil inlet; 603. Lower die oil delivery hose; 604. Upper die oil delivery hose; 7. Stamping lubrication system; 701. Oil inlet through hole; 702. Tesla valve type unidirectional flow control channel; 8. Exposed radial bifurcated flow channel; 801. Grooved flow channel; 802. Grooved bifurcated flow channel; 9. Oil-loving layer; 10. Hydrophobic layer; 11. Groove oil storage; 12. Micro-boss oil trace. Detailed implementation manners

[0036] Example 1: As Figures 1 to 11 shown, the present invention relates to a forming device for a high-gloss stainless steel plate. A forming device for a high-gloss stainless steel plate, characterized in that it includes a stamping device 1, a fixed workbench 2 provided at the upper workbench of the stamping device 1, and a moving workbench 3 provided at the hydraulic end of the stamping device 1; A forming die 4 for stamping and processing a high-gloss stainless steel hub cap 5 is jointly arranged on the fixed workbench 2 and the moving workbench 3, and an oil pumping assembly 6 connected to the forming die 4 for realizing quantitative lubricating oil supply is arranged at the rear side of the stamping device 1; The forming die 4 includes a lower die body 401 and an upper die body 402 respectively arranged on the fixed workbench 2 and the moving workbench 3. A concave forming cavity 403 for stamping the concave surface of the high-gloss stainless steel hub cap 5 is machined at the top of the lower die body 401, and a convex forming cavity 405 for stamping the convex surface of the high-gloss stainless steel hub cap 5 is machined at the bottom of the upper die body 402. A stamping lubrication system 7 is commonly opened at the center inside the lower die body 401 and the upper die body 402 and is distributed on the concave forming cavity 403 and the convex forming cavity 405. When the lower die body 401 and the upper die body 402 are closed, a stamping combined die forming cavity 407 for realizing the stamping forming of the high-gloss stainless steel hub cap 5 is formed between the concave forming cavity 403 and the convex forming cavity 405; The stamping lubrication system 7 expands the lubricating oil to the die working surface through capillary action. The exposed lubricating oil in the stamping lubrication system 7 is compressed by the closing pressure to generate a pressure gradient, so that the exposed lubricating oil is directionally released to the upper and lower surfaces of the stainless steel plate to form an oil film. And the pressure unloading causes the lubricating oil to flow back and replenish to form a dynamic lubrication cycle.

[0037] In the present invention, through the combination of the Tesla valve type unidirectional flow control channel and the exposed radial bifurcated flow channel, the lubricating oil is evenly diffused to the die working surface by using capillary action and the oilophilic coating, and the overflow position of the lubricating oil is precisely controlled through the hydrophobic layer to form a uniform micro-protrusion oil trace. The height of the oil trace and the thickness of the oil film can be accurately calculated to ensure that during the stamping process of the complex curved surface of the hub cap, the uniformity error of the surface oil film thickness is controlled within ±5%, and the surface roughness Ra value is stably maintained at 0.1 The following effectively avoids scratches and contamination and significantly improves the high-gloss surface quality of the hub cap.

[0038] In the embodiment of the present invention, the stamping lubrication system 7 includes two oil inlet through holes 701 respectively opened at the center inside the lower die body 401 and the upper die body 402, two groups of Tesla valve type unidirectional flow control channels 702 for realizing passive unidirectional flow control of the lubricating oil, and two groups of exposed radial bifurcated flow channels 8 respectively arranged in an annular array on the surfaces of the concave forming cavity 403 and the convex forming cavity 405. The two groups of Tesla valve type unidirectional flow control channels 702 are respectively arranged in an annular array inside the lower die body 401 and the upper die body 402, and the Tesla valve type unidirectional flow control channel 702 is connected to the corresponding oil inlet through hole 701. The exposed radial bifurcated flow channel 8 includes a groove-shaped flow channel 801 and a plurality of groove-shaped bifurcated flow channels 802. One end of the groove-shaped flow channel 801 is connected to the corresponding Tesla valve type unidirectional flow control channel 702, and the plurality of groove-shaped bifurcated flow channels 802 are symmetrically distributed on both sides of the groove-shaped flow channel 801 and are connected to the groove-shaped flow channel 801. The plurality of groove-shaped flow channels 801 extend radially away from the Tesla valve type unidirectional flow control channel 702 in equal proportion starting from the Tesla valve type unidirectional flow control channel 702.

[0039] Among them, the groove-shaped flow channel 801 and the groove-shaped bifurcated flow channel 802 make the lubricating oil diffuse along the channel to the working surface of the mold based on capillary action, that is, the surfaces of the concave forming cavity 403 and the convex forming cavity 405. During the stamping process, the lubricating oil exposed outside the channel forms micro-protrusion oil traces 12 through the hydrophobic layer 10. During the gradually pressurized process, the lubricating oil in the channel generates a pressure gradient due to compression and is directionally released to the surface of the workpiece through the micro-protrusion oil traces 12 in the exposed part. After the pressure is unloaded, the surface tension drives the lubricating oil to flow back and replenish, forming a dynamic lubrication cycle.

[0040] And it is limited by the Tesla valve-type one-way flow control channel 702 connected to the groove-shaped flow channel 801 to realize the passive one-way flow control of the fluid, which is transformed into the uniform diffusion control of the lubricating oil. By utilizing the surface tension, viscous force and flow channel geometric constraints of the micro-scale capillary structure, the uniform distribution of the lubricating oil from the fixed-point input to the mold surface is realized, and at the same time, the reverse overflow of the lubricating oil during high-pressure forming is prevented; The present invention realizes the dynamic recycling of the lubricating oil. When the pressure is unloaded, the lubricating oil flows back to the groove-shaped flow channel under the action of the surface tension and the coating, and the reflux coefficient reaches 0.6 - 0.8, reducing the waste of lubricating oil by more than 40% compared with the traditional process. At the same time, the cold oil pump adopts an adaptive fuzzy PID control algorithm to adjust the oil delivery flow rate, match the stamping working condition requirements in real time, avoid excessive oil supply, and further reduce the lubricating oil usage cost. The lubricating oil consumption for single-batch production of hub caps can be reduced by 35% - 45%.

[0041] In the embodiment of the present invention, an oil-loving layer 9 is deposited on the inner walls of the groove-shaped flow channel 801 and the groove-shaped bifurcated flow channel 802 by magnetron sputtering, and a hydrophobic layer 10 is sprayed on the non-flow channel areas on the inner walls of the concave forming cavity 403 and the convex forming cavity 405. The lubricating oil flowing in the groove-shaped flow channel 801 and the groove-shaped bifurcated flow channel 802 under the influence of capillary action forms groove oil storage 11, and the groove oil storage 11 forms micro-protrusion oil traces 12 for directional oil film release and reflux replenishment outside the groove-shaped flow channel 801 and the groove-shaped bifurcated flow channel 802 under the influence of the hydrophobic layer 10.

[0042] Among them, the oil-loving layer 9 deposits a diamond-like carbon coating DLC with a thickness of 5 - 10 μm on the inner wall of the channel by magnetron sputtering, and the surface energy is increased to 40 mN / m, and the contact angle < 25°; The hydrophobic layer 10 sprays a fluorosilane super-hydrophobic coating in the non-flow channel area, with a thickness of 20 - 50 μm, the contact angle > 160°, and the rolling angle < 5°; For the forming of stainless steel plates, it is recommended to use synthetic ester oils with a viscosity of 80 - 150 cSt, such as pentaerythritol ester, which has a viscosity retention rate > 90% under a pressure of 200 MPa, a surface tension coefficient of 25 - 30 mN / m, balancing fluidity and anti - spillage ability, and adding 0.5% - 1% of molybdenum disulfide The nanoparticle size is 50 - 100 nm, which can reduce the friction coefficient of the lubricating oil by 30%, while enhancing the oil film strength and reducing the risk of oil film rupture under high pressure.

[0043] In an embodiment of the present invention, a circular hole forming boss 404 for stamping the assembly hole 501 on the high - brightness stainless steel hub cap 5 is constructed at the center of the concave forming cavity 403. Delivery interfaces 406 connected to the corresponding oil inlet through - holes 701 are installed on one side of both the lower die body 401 and the upper die body 402.

[0044] In an embodiment of the present invention, the oil pumping assembly 6 includes a cold oil pump 601 provided on the back of the stamping device 1 and an oil inlet 602 provided on the cold oil pump 601. Two oil outlet ends of the cold oil pump 601 are respectively connected to a lower die oil delivery hose 603 and an upper die oil delivery hose 604, and the lower die oil delivery hose 603 and the upper die oil delivery hose 604 are respectively connected to the corresponding delivery interfaces 406.

[0045] Embodiment Two: As Figures 1 to 11 shown, a manufacturing process of a stainless steel hub cap based on high - brightness stainless steel plates includes the following steps: S1: Sheet and equipment preparation: After cutting the high - brightness stainless steel plate into a suitable size, place it above the lower die body 401. Connect the oil outlet pipeline of the external oil storage device to the oil inlet 602, and control the cold oil pump 601 through the stamping device 1. Based on the formula: Quantitatively deliver oil to the oil inlet through - holes 701 in the lower die body 401 and the upper die body 402. In the formula, is the surface area of the stainless steel hub cap, is the standard oil film thickness to ensure an ideal lubrication effect during stamping, is used to compensate for the lubricating oil loss during stamping, is the empirical loss coefficient, and , covering losses such as volatilization, adsorption, and residue, which can be optimized through statistical analysis of historical production data; S2: Lubricating oil pre - distribution: The lubricating oil flows into the Tesla - valve type unidirectional flow control channel 702 through the oil inlet through - hole 701, and then diffuses along the groove - shaped flow channel 801 and the groove - shaped bifurcated flow channel 802 by capillary action. The lubricating oil is constrained within the flow channel by the oil - loving layer 9 of the inner wall hydrophilic coating. The diffusion speed of the lubricating oil in the flow channel satisfies the formula . In the formula, is the surface tension of the lubricating oil, which is the driving force for the lubricating oil to spread. is the contact angle between the lubricating oil and the oil - wettable coating. The smaller the contact angle, the stronger the oil - wettable effect and the easier the spread. is the dynamic viscosity of the lubricating oil. The greater the viscosity, the greater the flow resistance. is the equivalent radius of the flow channel, which reflects the influence of the flow channel size on the flow velocity. S3: Stamping forming and dynamic lubrication: The stamping equipment 1 drives the moving workbench 3 to drive the upper die body 402 to move downward for die - closing, forming a stamping die - closing forming cavity 407. At the same time, the round - hole forming boss 404 punches out the assembly hole 501. During the die - closing process, the cold oil pump 601 continuously replenishes oil, and the lubricating oil forms a micro - convex - platform oil trace 12 at the edge of the flow channel under the action of the hydrophobic layer 10. The height of the micro - convex - platform oil trace is calculated by the formula In the formula, is the volume of the overflowing lubricating oil, which is the actual volume of the lubricating oil overflowing from the flow channel. is the surface area of the flow channel edge, that is, the boundary area where the lubricating oil overflows. The micro - convex - platform oil trace 12 generates a pressure gradient under the die - closing pressure According to the formula In the formula, is the pressure exerted by the die during the die - closing process, which is set by the hydraulic system of the stamping equipment and monitored in real - time. is the actual contact area between the die and the stainless - steel sheet, which is estimated through the die design dimensions and the deformation of the sheet. Utilizing the one - way blocking characteristic of the Tesla - valve - type one - way flow control channel 702, the micro - convex - platform oil trace 12 is directionally released to form an oil film. The thickness of the oil film satisfies the formula In the formula, is the stamping speed of the die. is the flow characteristic length of the oil film. S4: Pressure unloading and lubricating oil reflux: After stamping is completed, the pressure is unloaded. The lubricating oil, under the action of the surface tension and the hydrophobic layer 10, flows back to the groove - shaped flow channel 801 and the groove - shaped bifurcated flow channel 802 according to the formula In the formula, is the volume of the lubricating oil remaining on the die surface and in the micro - convex - platform oil trace during pressure unloading. is the reflux coefficient, which reflects the efficiency of the surface - tension - driven reflux and is related to the surface tension of the lubricating oil and the characteristics of the oil - repellent layer, and to form a decayed micro - convex - platform oil trace 12. S5: Demoulding and oil replenishment: Separate the lower die body 401 from the upper die body 402 to take out the formed hub cap, and calculate the lubricating oil shortage , through the formula It is concluded that the cold oil pump 601, according to refills the lubricating oil and enters the next stamping cycle. In the formula, is the total volume of the lubricating oil injected before stamping, i.e., in step S1, is the volume of the lubricating oil that actually flows back and can be reused; The present invention also significantly reduces die wear through a uniform and stable lubrication effect. By precisely controlling the oil film thickness and pressure gradient, the dry friction between the die and the stainless steel plate is reduced, and the wear of the key components of the die is reduced by more than 50%. The service life is extended to 1.5 - 2 times that of the traditional die. In addition, the automatic dynamic adjustment function of the system can respond in real time to changes in stamping speed, pressure, and temperature, ensuring a stable lubrication effect throughout the production cycle. The defective product rate of the product is reduced from 8% - 12% of the traditional process to less than 3%, greatly improving production efficiency and product quality stability, and reducing the comprehensive production cost.

[0046] As another embodiment of the present invention, in step S3, the Tesla valve type unidirectional flow control channel 702 adopts a three - stage bifurcated asymmetric contraction - expansion structure, with the forward flow resistance reduced by 50% and the reverse flow attenuation rate ≥80%.

[0047] As another embodiment of the present invention, in step S5, the oil delivery flow rate of the cold oil pump 601 is adjusted by using an adaptive fuzzy PID control algorithm, and the control formula is: In the formula, is the flow error, is the error change rate, , , are the proportional, integral, and differential coefficients dynamically adjusted based on fuzzy rules.

[0048] Example 3: In actual production, taking the high - gloss stainless steel wheel hub cover of an automobile as the target, the forming equipment and manufacturing process of the present invention are experimentally verified, and the following examples are obtained: Test Preparation Equipment and Die: Manufacture a set of high - gloss stainless steel plate forming equipment that meets the requirements of the invention, including a stamping equipment 1, a fixed workbench 2, a moving workbench 3, a forming die 4, and a pump oil assembly 6. Among them, the depth of the concave forming cavity 403 of the lower die body 401 of the forming die 4 is 30 mm, the radius of curvature of the convex forming cavity 405 of the upper die body 402 is 50 mm, and the diameter of the round hole forming boss 404 is 10 mm.

[0049] Materials: Select a high - gloss stainless steel plate with a thickness of 1 mm and an area of 0.05 m² as the blank; use a synthetic ester - based lubricating oil with a viscosity of 100 cSt and add 0.8% of molybdenum disulfide nano - particles.

[0050] Measuring instruments: Use a surface roughness measuring instrument with an accuracy of 0.01 Measure the surface roughness of the product; use an electronic balance with an accuracy of 0.1 g to measure the amount of lubricating oil used; use a mold wear measuring instrument with an accuracy of 1 Detect the mold wear amount; use a pressure sensor with an accuracy of 0.1 MPa to monitor the mold closing pressure.

[0051] Test process Traditional process test: Conduct stamping using the traditional method of applying lubricating oil to the mold. Manually apply 50 ml of lubricating oil before each stamping. Conduct 100 stamping tests and record the surface roughness, actual amount of lubricating oil used, mold wear amount, and number of defective products of the high-gloss stainless steel hub caps after each stamping.

[0052] Process test of the present invention: Conduct tests according to the manufacturing process of the invention. Set the standard oil film thickness to be 8 , take the empirical loss coefficient as 0.2, and the surface area of the stainless steel hub cap is measured to be 0.04 m 2 , according to the formula calculate that 32 ml of oil is quantitatively supplied to the oil inlet through holes 701 in the lower die body 401 and the upper die body 402 before each stamping. Similarly, conduct 100 stamping tests. During each stamping process, use a pressure sensor to monitor the mold closing pressure , estimate the contact area between the mold and the sheet according to the mold design dimensions and the sheet deformation situation , calculate the oil trace height of the micro-protrusions , pressure gradient and oil film thickness and other parameters; after stamping is completed, measure the mold wear amount, remaining amount of lubricating oil, and count the number of defective products.

[0053] Comparison of test data

[0054] Test conclusions Improvement of surface quality: Through the unique lubrication system design of the present invention, the Ra value of the surface roughness of the high-gloss stainless steel hub cap is stabilized below 0.1 , which is significantly lower than that of the traditional process, effectively avoiding scratches and contamination and improving the high-gloss surface quality of the product.

[0055] Reduction of lubricating oil loss: The present invention realizes the dynamic recycling of lubricating oil, reduces the single-use amount of lubricating oil by about 36%, and the lubricating oil reflux rate reaches about 75%, reducing the lubricating oil use cost.

[0056] Mold Life Extension and Production Efficiency Improvement: The uniform and stable lubrication effect reduces the mold wear by more than 55%, and extends the service life to about twice that of traditional molds. At the same time, the defective product rate of the product drops from 10% to below 3%, greatly improving the production efficiency and product quality stability, and reducing the comprehensive production cost.

[0057] The embodiments disclosed in the present invention are preferred embodiments, but not limited thereto. Those of ordinary skill in the art can easily understand the spirit of the present invention based on the above embodiments and make different extensions and changes. However, as long as they do not depart from the spirit of the present invention, they are within the protection scope of the present invention.

Claims

1. A forming device for a high-gloss stainless steel plate, characterized in that It includes a stamping device, a fixed stationary table disposed at the workbench of the stamping device, and a movable table disposed at the hydraulic end of the stamping device; A forming die is jointly arranged on the stationary table and the movable table, and a pump oil assembly connected to the forming die is arranged at the rear side of the stamping device; The forming die includes a lower die body and an upper die body respectively arranged on the stationary table and the movable table. A concave surface forming cavity for stamping and forming the concave surface on the stainless steel hub cap is machined at the top of the lower die body, and a convex surface forming cavity for stamping and forming the convex surface on the stainless steel hub cap is machined at the bottom of the upper die body. A stamping lubrication system distributed on the concave surface forming cavity and the convex surface forming cavity is jointly opened at the center in the lower die body and the upper die body. When the lower die body and the upper die body are closed, the concave surface forming cavity and the convex surface forming cavity form a stamping closing forming cavity for realizing the stamping forming of the stainless steel hub cap; The stamping lubrication system expands the lubricating oil to the mold working surface through capillary action. The lubricating oil exposed in the stamping lubrication system is compressed by the closing pressure to generate a pressure gradient, so that the exposed lubricating oil is directionally released to the upper and lower surfaces of the stainless steel plate to form an oil film, and the pressure unloading causes the lubricating oil to flow back and replenish to form a dynamic lubrication cycle.

2. The forming device for a high-brightness stainless steel plate according to claim 1, characterized in that, The stamping lubrication system includes two oil inlet through holes respectively opened at the center in the lower die body and the upper die body, two Tesla valve type one-way flow control channels for realizing passive one-way flow control of the lubricating oil, and two exposed radial bifurcated channels respectively opened on the surfaces of the concave surface forming cavity and the convex surface forming cavity in an annular array. The two Tesla valve type one-way flow control channels are respectively opened in the lower die body and the upper die body in an annular array, and the Tesla valve type one-way flow control channel is connected to the corresponding oil inlet through hole.

3. The forming device for a high-gloss stainless steel plate according to claim 2, characterized in that, The exposed radial bifurcated channel includes a groove-shaped channel and a plurality of groove-shaped bifurcated channels. One end of the groove-shaped channel is connected to the corresponding Tesla valve type one-way flow control channel, and a plurality of the groove-shaped bifurcated channels are symmetrically distributed on both sides of the groove-shaped channel and are connected to the groove-shaped channel. The plurality of groove-shaped channels extend radially away from the Tesla valve type one-way flow control channel in equal proportion starting from the Tesla valve type one-way flow control channel.

4. The forming device for a high-brightness stainless steel plate according to claim 3, wherein, The inner walls of the groove-shaped channel and the groove-shaped bifurcated channels are magnetron sputtered with an oil-loving layer, and the non-channel areas on the inner walls of the concave surface forming cavity and the convex surface forming cavity are sprayed with a hydrophobic layer. The lubricating oil flowing in the groove-shaped channel and the groove-shaped bifurcated channels under the influence of capillary action forms groove oil storage, and the groove oil storage forms micro-convex oil traces for directional oil film release and reflux replenishment outside the groove-shaped channel and the groove-shaped bifurcated channels under the influence of the hydrophobic layer.

5. The forming device for a high-brightness stainless steel plate according to claim 4, wherein, A round hole forming boss for stamping the assembly hole on the stainless steel hub cap is constructed at the center of the concave surface forming cavity, and a conveying interface connected to the corresponding oil inlet through hole is installed on one side of the lower die body and the upper die body.

6. The forming device for a high-brightness stainless steel plate according to claim 5, characterized in that, The oil pumping assembly includes a cold oil pump disposed on the back of the stamping equipment and an oil inlet disposed on the cold oil pump. Two oil outlet ends of the cold oil pump are respectively connected to a lower die oil delivery hose and an upper die oil delivery hose, and the lower die oil delivery hose and the upper die oil delivery hose are respectively connected to the corresponding delivery interfaces.

7. A manufacturing process for a stainless steel wheel hub cover based on a high-gloss stainless steel plate, which is applicable to the forming equipment for a high-gloss stainless steel plate according to any one of claims 1-6, characterized in that, The steps include: S1: Sheet material and equipment preparation: Cut the high-gloss stainless steel sheet into a suitable size and place it above the lower die body. Connect the oil outlet pipeline of the external oil storage equipment to the oil inlet, and control the cold oil pump through the stamping equipment to quantitatively deliver oil into the oil inlet holes in the lower die body and the upper die body. S2: Lubricating oil pre-distribution: The lubricating oil flows into the Tesla valve type unidirectional flow control channel through the oil inlet hole, and then diffuses along the groove-shaped flow channel and the groove-shaped bifurcated flow channel by capillary action. The lubricating oil is constrained in the flow channel by the oil-affinity layer of the inner wall oil-affinity coating. S3: Stamping forming and dynamic lubrication: The stamping equipment drives the moving workbench to drive the upper die body to move downward to close the die, forming a stamping die closing and forming cavity. At the same time, the round hole forming boss punches out the assembly hole. During the die closing process, the cold oil pump continuously supplies oil. The lubricating oil forms a micro-protrusion oil trace at the edge of the flow channel under the action of the hydrophobic layer, and uses the unidirectional blocking characteristic of the Tesla valve type unidirectional flow control channel to make the micro-protrusion oil trace release directionally to form an oil film. S4: Pressure unloading and lubricating oil reflux: After stamping is completed, the pressure is unloaded. The lubricating oil flows back to the groove-shaped flow channel and the groove-shaped bifurcated flow channel under the action of surface tension and the hydrophobic layer, forming a decayed micro-protrusion oil trace. S5: Demoulding and oil quantity replenishment: Separate the lower die body and the upper die body to take out the formed hub cap, calculate the lubricating oil shortage amount, and replenish the lubricating oil through the cold oil pump to enter the next stamping cycle.

8. The manufacturing process of a stainless steel wheel hub cover based on a high-brightness stainless steel plate according to claim 7, characterized in that, In the step S3, the Tesla valve type unidirectional flow control channel adopts a three-stage bifurcated asymmetric contraction-expansion structure, the forward flow resistance is reduced by 50%, and the reverse flow attenuation rate ≥ 80%.

9. The manufacturing process of a stainless steel wheel hub cover based on a high-brightness stainless steel plate according to claim 7, characterized in that, In the step S5, the oil delivery flow rate of the cold oil pump is adjusted by using an adaptive fuzzy PID control algorithm, and the control formula is: , where is the flow error, is the error change rate, , , are the proportional, integral, and differential coefficients dynamically adjusted based on fuzzy rules.

10. The manufacturing process of a stainless steel hubcap based on a high-brightness stainless steel plate according to claim 7, characterized in that, In the step S3, the height of the oil stain on the micro-protrusions is calculated by the formula , where is the volume of the overflow lubricating oil, is the surface area of the runner edge, and the oil stain on the micro-protrusions generates a pressure gradient under the clamping pressure . According to the formula , where is the pressure applied by the mold during the clamping process, is the contact area between the mold and the plate

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