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  • 2022.11.11

    How to deal with the problem of press injury of die stamping parts

    Stamping is one of the forming production processes for large quantities of parts. Mold failure is the most common problem in stamping production, which often causes production stoppage and affects the production cycle of products. Therefore, it is necessary to find the cause of mold failure as soon as possible and maintain it reasonably.What are the reasons for the jumping chips and crushing of the stamping parts in the stamping die factory, and what countermeasures should be taken?The causes of chip jumping and crushing of die stamping parts and the corresponding countermeasures are as follows:1) When the clearance is too large, control the machining accuracy of the punch and die or modify the design clearance;2) In case of improper feeding, trim the tape and clean the mold in time when it needs to be sent to the proper position;3) The stamping oil drops too fast, and the oil is sticky. Control the amount of stamping oil drops or change the oil type to reduce the viscosity;4) The mold is not demagnetized, and it must be demagnetized after study (more attention should be paid to the iron stamping materials);5) The punch is worn and scraps are attached to the punch, so the punch knife edge needs to be studied;6) If the punch is too short and the length of the inserted die is insufficient, the length of the punch blade into the die shall be adjusted;7) The material is hard and the punching shape is simple. Ejectors can be installed on the end face of the punch edge or chamfers or arcs can be trimmed to reduce the fitting area between the end face of the punch edge and the chipsThe emergency measures are:Reduce the sharpness of the die edge, reduce the amount of research and study on the die edge, increase the roughness (coating) of the straight edge surface of the die, use a vacuum cleaner to absorb waste materials, reduce the impact speed, and slow down chip jumping.

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  • 2022.11.04

    What are the maintenance points of continuous stamping die

    It is very necessary to do a good job in the maintenance of the continuous stamping die in the process of use, and it is more necessary to carry out careful and patient maintenance, so as to ensure the safety and usability of the continuous stamping die.So, do you know what maintenance points are for the continuous stamping die?1. Maintenance of punch and dieWhen disassembling the male and female die, pay attention to the original condition of the die, so that it can be easily restored during subsequent mold installation. If there is padding or displacement, the thickness of the gasket shall be engraved on the parts, and records shall be made.When replacing the punch, try to insert the stripper to see whether the die is smooth and whether the clearance between the plug and the die is even; When replacing the female die, check whether the clearance between the insertion and the punch is even.As the punch becomes shorter after grinding, it is necessary to add gasket to reach the required length. Check whether the effective length of the punch is sufficient. To replace the broken punch, find out the cause, and at the same time, check whether the corresponding die has a broken edge and whether it needs to grind the edge.When assembling the punch, check whether the clearance between the punch and the fixed block or the fixed plate is sufficient, and if there is a pressure block, check whether there is movement allowance; When assembling the female die, it shall be placed horizontally, and then a flat iron block shall be placed on the female die surface. It shall be gently knocked into place with a copper rod. It is not allowed to strike the female die with force at an angle. The bottom of the female die shall be chamfered. After installation, check whether the die surface is flush with the die surface.After the punch, die and mold core are assembled, the care belt shall be checked as necessary to see whether the parts are installed incorrectly or reversely, whether the die and die cushion block are installed reversely, whether the blanking hole is blocked, whether the new parts need to steal materials, whether the materials need to be stolen are enough, and whether the parts that need to be locked are locked.Pay attention to confirm the locking of the stripper plate screws. When locking, use balanced force to cross lock from the inside to the outside. Do not lock one screw first and then another to avoid tilting the stripper plate, leading to punch fracture or lower mold accuracy.2. Maintenance of stripper plateTo remove the stripper, first use two elevators to pry it up, and then use both hands to balance the force to take it out. In case of difficulty in disassembly, check whether the inside of the mold is cleaned, whether all the locking screws are disassembled, and whether the mold is damaged due to material jamming. Find out the cause and then do the corresponding treatment. Do not blindly dispose.When assembling the stripper plate, first clean the punch and stripper plate, add lubricating oil at the guide post and punch guide, put them in steadily, then press them in place with both hands, and repeat several times.If it is too tight, find out the cause (whether the guide pillar and guide sleeve are guided normally, whether each part is damaged, whether the new punch can pass smoothly, and whether the position of the stripper plate is correct), find out the cause, and then handle it accordingly.If there is pressure block on the fixed plate, check whether the space on the stripper back plate is enough. The material contact surface between the stripper plate and the female die is stamped for a long time to produce indentation. When the indentation is serious, it will affect the pressing accuracy of the material, resulting in abnormal product size, instability, etc. The stripper insert and stripper plate need to be repaired or reground.The contour sleeve shall be checked for accuracy. Unequal height will cause the stripper plate to tilt, and its precise guidance and stable spring compression functions will be damaged, so it must be maintained.3. Guide part inspectionCheck the fit clearance of the guide post and guide sleeve, whether there are burns or wear marks, and whether the oil supply of the die guide is normal. The wear of the guide parts and the damage of the precision will reduce the precision of the mold, and problems will occur in various parts of the mold. Proper maintenance and regular replacement must be carried out.Check the accuracy of the guide part. If the guide pin is worn and has lost its proper accuracy and function, it must be replaced. Check the condition of the stripper spring and ejector spring to see if they are broken, or if they have been used for a long time without breaking but have lost their original strength due to fatigue, they must be regularly maintained and replaced, otherwise, they will cause damage to the mold or the production will not be smooth.4. Adjustment of die clearanceThe positioning hole of the die core is worn due to frequent and repeated combination of the die core, resulting in large clearance after assembly (looseness after assembly) or uneven clearance (positioning deviation), which will cause the shape of the section after punching and cutting to become worse, the punch is easy to break, and burrs are generated. The appropriate clearance can be adjusted through the inspection of the section after punching and cutting.When the clearance is small, the section is small, and when the clearance is large, the section is large and the burr is large, so the reasonable clearance can be obtained by shifting. After adjustment, proper records should be made, or marks can be made at the die edge, so as to facilitate subsequent maintenance.

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  • 2022.10.25

    What are the classifications of continuous stamping dies

    Continuous stamping die is a special process equipment that processes materials (metal or non-metal) into parts (or semi-finished products) in cold stamping process, which is called cold stamping die (commonly known as cold stamping die).So, do you know the classification of continuous stamping dies?1. Open die: blanking parts with simple structure, small size, light weight, easy manufacturing, low cost, low service life, poor accuracy, low accuracy requirements, simple beginning, small batch or trial production.2. Guide plate type: the precision is higher than that of the open die, and it is suitable for blanking parts with simple start and small workpiece size. The stroke of the press is required not to be greater than the thickness of the guide plate.3. Guide pillar type: guide pillar ensures even blanking clearance, high dimensional accuracy of blanking parts, long service life of die, convenient installation, and suitable for mass production.4. Continuous die: strip material shall be accurately positioned to ensure the mutual position accuracy between inner hole and contour. High productivity, with a certain blanking accuracy, suitable for mass production.5. Compound die: The internal and external shapes of stamping parts have high mutual position accuracy, which is suitable for mass production.

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  • 2022.10.14

    What are the skills in the development, design and manufacture of stamping dies

    The development, design and manufacture of stamping dies is a complex and cumbersome process. If you want to know what skills are in the development, design and manufacture of stamping dies, the following are some points for your reference.1. Information from the waste situationScrap is essentially the reverse image of the forming hole. When developing, designing and manufacturing stamping dies, we must learn to see problems from the scrap. By checking the scrap, you can tell if the upper and lower die gaps are correct. If the gap is too large, the waste will appear rough and undulating. The larger the gap, the greater the angle the fracture surface makes with the bright band area. If the gap is too small, the scrap will exhibit a small angled fracture surface and a wide bright band area. An ideal scrap should have a reasonable collapse angle and a uniform bright band, which can keep the punching force to a minimum and form a neat round hole with very few burrs. Therefore, in the manufacturing process, learn to see information from the scrap. . Second, the choice of mold clearance1. During the development, design and manufacture of stamping die, the clearance of the die is related to the type and thickness of the material being punched. Unreasonable clearance can cause the following problems:2. If the gap is too large, the burr of the stamped workpiece will be relatively large, and the stamping quality will be poor. If the gap is too small, although the quality of punching is good, the wear of the die is serious, which greatly reduces the service life of the die, and it is easy to cause the breakage of the punch;3. If the gap is too large or too small, the material will be damaged, which will affect the actual use of the material;4. Reasonable clearance can prolong the life of the mold, the unloading effect is good, the burr and flanging are reduced, the plate is kept clean, and the hole diameter is consistent without scratching the plate, reducing the degree of damage of the material, and allowing the material to exert its own value.3. How to improve the service life of the moldFor users, improving the service life of the mold can greatly reduce the stamping cost. The factors that affect the development, design and manufacture of die stamping die are as follows:1. The type and thickness of the material; 2. Whether a reasonable manufacturing gap is selected; 3. The structure of the mold; 4. Whether the material is well lubricated during stamping; Whether the gaskets in the mold are used reasonably; 7. Whether the mold base of the machine tool has been worn, etc. These are the reasons that need to be paid attention to in the manufacturing process.

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  • 2022.10.09

    The material of the stamping die is not good, and it is easy to be broken during processing

    Due to different stamping processes and different working conditions, there are many reasons for the bursting of stamping dies, and the life of dies of different materials is often different. To this end, the basic requirements for the material of the working parts of the die are put forward:(1) The performance of the material should have high hardness (58-64HRC) and high strength, as well as high wear resistance and sufficient toughness, small heat treatment deformation, and certain hot hardness;(2) The process performance is good. The processing and manufacturing process of the working parts of the die is generally complicated, therefore, it must have adaptability to various processing techniques, such as forgeability, machinability, hardenability, hardenability, quenching crack sensitivity and grinding workability, etc. .Heat treatment: deformation caused by improper quenching and tempering processPractice has proved that the thermal processing quality of the mold has a great influence on the performance and service life of the mold. According to the analysis and statistics of the reasons for the failure of the mold, the "accidents" of mold failure caused by improper heat treatment account for more than 40%.(1) Forging process: This is an important link in the manufacturing process of mold working parts. For molds of high alloy tool steel, technical requirements are usually put forward for metallographic structures such as material carbide distribution.(2) Preliminary heat treatment: Depending on the material and requirements of the working parts of the mold, preliminary heat treatment processes such as annealing, normalizing or quenching and tempering should be used to improve the structure, eliminate the structural defects of the forging blank, and improve the processing technology. After proper preparatory heat treatment, the high carbon alloy die steel can eliminate the reticulated secondary cementite or chain carbide, make the carbide spheroidized and refined, and promote the uniformity of carbide distribution, which is conducive to ensuring quenching and tempering. quality, improve mold life.(3) Quenching and tempering: This is the key link in the heat treatment of the mold. If overheating occurs during quenching and heating, it will not only cause greater brittleness of the workpiece, but also easily cause deformation and cracking during cooling, which will seriously affect the life of the mold. When the die is quenched and heated, special attention should be paid to preventing oxidation and decarburization, and the heat treatment process specification should be strictly controlled. When conditions permit, vacuum heat treatment can be used. After quenching, it should be tempered in time, and different tempering processes should be adopted according to technical requirements.(4) Stress relief annealing: After rough machining, the mold working parts should be subjected to stress relief annealing treatment. The purpose is to eliminate the internal stress caused by rough machining, so as to avoid excessive deformation and cracks during quenching. For molds with high precision requirements, stress relief tempering is required after grinding or electrical machining, which is conducive to stabilizing mold accuracy and improving service life.

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  • 2022.10.05

    The solution to demoulding

    Why is the problem of demolding difficult? 1) There are grooves in the mold; 2) Insufficient demoulding slope; 3) The mold finish is not high. Failures caused by insufficient drafting slope are very common. When designing products, the drafting slope must be marked on the drawing. The drafting slope is usually in the range of 1 to 2 degrees. It is better to be as large as possible, and it is also allowed to be more than 0.5 degrees in special occasions. If the injection pressure is too high, the product is too close to the mold, and demolding becomes difficult. In order to smoothly release the product from the mold, generalists use a release agent containing silicone oil, but when using the release agent, only a very thin layer can be applied. If the spray is too thick, it is difficult to wipe off. In addition, due to the action of the release agent, the secondary processing such as printing marks on the product becomes very bad. Once the release agent coated on the mold is attached to the product, it is quite difficult to wipe it off.   Based on the above root cause, come up with a solution: 1. Immediately: reduce the injection pressure, shorten the pressure holding time, reduce the mold temperature, reduce the demolding speed, spray the mold release agent 2. Short term: Improve the finish of the mold cavity 3. Long-term: increase the demoulding slope and increase the number of demolding pins For heavy and hard materials, such as GPPS, it is common for products to break due to insufficient lift off. For both sticky and soft materials, such as PE, it is possible to cut off the product in several pieces. The PVC drain pipe is mainly used for water supply, and the diameter of the drain pipe is generally 50-75-110-160 and so on. The PVC drainage pipe is made of sanitary polyvinyl chloride (PVC) resin as the main raw material, adding an appropriate amount of stabilizers, lubricants, fillers, color enhancers, etc., through extrusion molding by plastic extruder and injection molding by injection molding machine. Curing, shaping, inspection, packaging and other processes to complete the production of pipes and fittings. PVC drainage pipe is an alternative to traditional drainage pipes and has better physical and chemical properties. It has a smooth inner wall and lower frictional resistance than conventional drainage materials, so the installation slope of the transverse pipe is smaller, which can improve the indoor clear height of the building. At the same time, the PVC drainage pipe is light in weight, one-fifth of the cast iron pipe, easy to transport and operate; it adopts adhesive connection, which is convenient for installation and maintenance; the price is lower than that of conventional drainage pipes, which greatly reduces the project cost; strong corrosion resistance, It is widely used in construction sewage and rainwater pipeline systems. In addition, the widespread use of PVC drainage pipes is conducive to saving steel, which is of great significance for alleviating the shortage of steel in our country.

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  • 2022.09.29

    What is the main reason why the punch of the stamping die wears too fast

    Stamping die is a special process equipment that processes materials (metal or non-metal) into parts (or semi-finished products) in cold stamping, called cold stamping die (commonly known as cold stamping die).The mold gap is too small. Generally, the total gap of Jianhan molds is 20% and 25% of the material plate thickness.The alignment of the convex and concave molds is not good, including the lack of precision of the mold base, the mold guide components and the turret sleeve, which cause the mold to be bad for the towel parts.The temperature of the punch is too high, mainly due to the overheating of the punch caused by the continuous long-term stamping of the same die.Improper mold sharpening method results in mold annealing and increased wear.Local unilateral punching, such as nibbling, punching or shearing, the lateral force of aluminum alloy door and window fittings will cause the punch to deviate to one side, and the clearance of this side will be reduced, resulting in serious mold wear. If it is too high, it will cause the punch to deflect over the upper die, causing damage to the punch and die.The material of the mold will cause the rebound of the scrap, and its related factors:The sharpness of the die edge, the larger the fillet of the edge, the easier it is to cause the waste to rebound.The input modulus of the mold and the input modulus of each upper position of the machine tool are certain, and the mold modulus is small, which is easy to cause waste to rebound.The gap of the mold is reasonable. If the gap of the mold is not suitable, it is easy to cause the waste to rebound.Whether there is more oil on the surface of the processed sheet.The spring is fatigued and damaged.The method to prevent mold with material:Use a special anti-tape material die. Aluminum alloy door and window accessoriesMolds are often sharpened and demagnetized.Increase the die gap.The oblique edge n die is used instead of the flat edge die.The mold installs the ejector.Reasonably increase the input modulus of the mold.Check the fatigue strength of the die spring or discharge sleeve.Die alignment problemWhen the mold is in use, the wear amount on each side of the punch is different, and some parts have large scratches and wear faster. This situation is especially obvious on narrow rectangular molds. The main reasons for this problem are:The machine tool turret design or machining accuracy is insufficient. The main reason is that the alignment of the upper and lower turntables and the mold mounting seat is not good.The design of the mold or the addition of precision cannot meet the requirements.The precision of the guide sleeve of the die punch is not enough.Improper selection of die gap.Die mounts or die guide bushes are not well aligned due to long-term wear and tear.

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  • 2022.09.21

    What are the principles of selection of stamping die materials

    Stamping die is a special process equipment that processes materials (metal or non-metal) into parts (or semi-finished products) in cold stamping, called cold stamping die (commonly known as cold stamping die).In the stamping die, the stamping die factory uses various metal materials and non-metallic materials, mainly carbon steel, alloy steel, cast iron, cast steel, cemented carbide, low melting point alloy, zinc-based alloy, aluminum bronze, synthetic resin, Polyurethane rubber, plastic, etc.Materials used to make molds are required to have high hardness, high strength, high wear resistance, appropriate toughness, high hardenability, no deformation (or less deformation) during heat treatment, and resistance to cracking during quenching.The key to ensure the life of the die is to select the die material reasonably and implement the correct heat treatment process for the stamping die factory.For molds with different uses, they should be comprehensively considered according to their working conditions, stress conditions, properties of processed materials, production batches and productivity, etc., and focus on the performance of the above requirements, and then make decisions on steel grades and heat treatment. The corresponding selection of the process.When the production batch of stamping parts is large, die steel with high quality and good wear resistance should be selected as the material of the working parts of the die. For the other process structural parts of the mold and the part materials of the auxiliary structural parts, it should also be improved accordingly. When the batch size is not large, the material performance requirements should be appropriately relaxed to reduce the cost.When the material to be stamped is hard or has a large deformation resistance, the convex and concave dies of the die should be selected from materials with good wear resistance and high strength. When deep drawing stainless steel, aluminum bronze die can be used because it has better resistance to sticking.The guide post and guide bush require wear resistance and good toughness, so the surface carburizing and quenching of low carbon steel is mostly used. For another example, the main disadvantage of carbon tool steel is poor hardenability. When the section size of the die parts is large, Its center hardness is still low after quenching, but when working on a press with a large number of strokes, its impact resistance is an advantage.For fixing plate, stripper plate and other parts, not only must have sufficient strength, but also require small deformation during the working process. In addition, cold and cryogenic treatment, vacuum treatment and surface strengthening can be used to improve the performance of mold parts. For cold extrusion dies with poor working conditions of convex and concave dies, metal dies should choose die steel with good comprehensive mechanical properties such as sufficient hardness, strength, toughness, wear resistance, etc., as well as certain red hardness and thermal fatigue strength, etc. .The hot and cold processability of the material and the current state of the plant should be considered.Pay attention to the use of micro-deformation die steel to reduce processing costs.For molds with special requirements, mold steel with special properties should be developed and used. The selection of mold materials should be determined according to the use conditions of mold parts, so as to select low-cost materials and reduce costs under the premise of meeting the main conditions.

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  • 2022.09.14

    Compression Model Heat Treatment: Fire Fire Engineering Illegal Production Transformation

    Stamping die is a special process equipment that processes materials (metal or non-metal) into parts (or semi-finished products) in cold stamping, called cold stamping die (commonly known as cold stamping die).Stamping is a pressure processing method that uses a die installed on a press to apply pressure to a material at room temperature to separate or plastically deform it to obtain the desired parts.Practice has proved that the thermal processing quality of the mold has a great influence on the performance and service life of the mold. According to the analysis and statistics of the reasons for mold failure, the "accidents" of mold failure caused by improper heat treatment account for more than 40%.(1) Forging processThis is an important link in the manufacturing process of mold working parts. For the mold of high alloy tool steel, technical requirements are usually put forward for the metallographic structure such as the carbide distribution of the material.(2) Preliminary heat treatmentPreparatory heat treatment processes such as annealing, normalizing or quenching and tempering should be used depending on the material and requirements of the working parts of the mold to improve the structure, eliminate the organizational defects of the forging blank, and improve the processing technology. After proper preparatory heat treatment, the high carbon alloy die steel can eliminate the reticulated secondary cementite or chain carbide, make the carbide spheroidized and refined, and promote the uniformity of carbide distribution, which is conducive to ensuring quenching and tempering. quality, improve mold life.(3) Quenching and temperingThis is the key link in the heat treatment of the mold. If overheating occurs during quenching and heating, it will not only cause greater brittleness of the workpiece, but also easily cause deformation and cracking during cooling, which will seriously affect the life of the mold. When the die is quenched and heated, special attention should be paid to preventing oxidation and decarburization, and the heat treatment process specification should be strictly controlled. When conditions permit, vacuum heat treatment can be used. After quenching, it should be tempered in time, and different tempering processes should be adopted according to technical requirements.(4) Stress relief annealingAfter rough machining, the working parts of the mold should be subjected to stress relief annealing treatment. The purpose is to eliminate the internal stress caused by rough machining, so as to avoid excessive deformation and cracks during quenching. For molds with high precision requirements, stress relief tempering is required after grinding or electrical machining, which is conducive to stabilizing mold accuracy and improving service life.

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  • 2022.09.07

    What are the advantages of stamping die production process

    The level of mold technology is an important indicator to measure the level of a country's manufacturing industry. With the further development of my country's industry, the mold industry is required to develop in the direction of large-scale, precise, efficient and multi-functional. One of the important ways is to combine mold and automation. .The key to the development of stamping dies is die manufacturing technology, die materials and die talents. The development of die technology is a key factor in the development of die industry. Its development goal is to meet the requirements of short delivery time, high precision, good quality and low price of die products. , One of the important directions is to vigorously develop mold automation.The automation development related to stamping dies is to combine traditional dies with opto-electromechanical technology, integrate multi-process automation modules into the dies, and realize full continuous die production through electrical control, thereby saving a lot of machines and manpower and maximizing efficiency. Process optimization, maximize benefits.Stamping refers to the process of installing a mold on a punching machine and passing a plate-shaped material between the molds, the stamping force deforms, cuts, bends, and forms the material. The stamping processes that can realize automatic processing include: hardware riveting, tapping Wire, self-riveting and mutual-riveting products, and integrated production of small components.The stamping process is widely used in the market because of its good interchangeability, material saving, and parts with thin walls, light weight, good rigidity, high surface quality and complex shapes that are difficult to manufacture by other processing methods. The production of stamping dies is manual, which greatly restricts its development.

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  • 2022.09.02

    What Is Auto Parts Mould

    When making parts for a car, the best way to create quality products is to use injection molding. Automotive parts have high quality and safety requirements, and injection molding is an irreplaceable advantage in the production process. Injection molding is an ideal solution for manufacturing plastic structural components. It can also be used for parts that are not usually injection molded, such as fluid handling plastic structural components. Plastic injection molding While metal and steel are traditionally associated with the automotive industry, plastic is becoming increasingly important in car manufacturing. Plastics are stronger and more durable than metal, and have many other advantages. Moreover, consumers today have a different set of expectations for their vehicles, and plastic injection molding is an excellent way to meet these expectations. Injection molding is an excellent option for automakers who want to manufacture high-quality parts at low costs. It allows companies to create intricate and complex designs with greater ease. The process also scales well for mass production and allows manufacturers to run tens of thousands of items through a mold at once. Injection molding uses high-pressure injection to shape polymer into desired shapes. Depending on the application, moulds can have single or multiple cavities. A single cavity mould can produce identical parts while multiple cavities can produce parts with different geometries. Tool steel moulds are typically used for injection molding, but stainless steel or aluminium moulds are also popular options. Die-casting Die-casting is a process used in making components used in autos and other vehicles. The production of these components is highly dependent on the materials used. Some of these materials are softer than others. For example, cast iron cannot sustain high pressures and it requires a special die. This type of die is expensive and requires significant start-up expenses. Another material commonly used in auto parts is magnesium, a lightweight metal with excellent strength-to-weight ratio. Because magnesium is naturally occurring, its abundance makes it an environmentally friendly option. Moreover, it can be recycled without leaving any traces behind. Die-casting for automobile parts can be done using cold chamber or hot chamber die-casting machines. Which process you choose will depend on the size and complexity of the parts. Some key players in the market include Altizon Inc., Endurance Technologies Ltd., and Georg Fischer Limited. These companies are involved in the production of complex die-cast parts and system components. Some of these companies also produce automotive-related machinery. Overmolding Overmolding is a process that involves combining different materials to form an automotive part. It is important to choose the correct material for a specific application. The adhesion between the material and substrate depends on three factors: surface texture, resin compatibility and surface treatment. A custom injection molder can guide you through these considerations and choose the right material for your application. Overmolded parts are stronger and more durable than non-moulded ones. This manufacturing process also eliminates the need for secondary operations, extra adhesives, and fasteners. The process saves a great deal of time and money, and is also highly convenient. In addition, overmolded parts have a protective layer of thermoplastic material that is flexible and durable. Overmolding can also help improve fuel efficiency and reduce vehicle weight. The process of replacing metal parts with plastic is one of the most efficient ways to make vehicles lighter. However, replacing heavy metal parts with plastic can be challenging, especially when they need to have high strength. Heavy metal parts require more expensive production processes and increase vehicle weight. Using overmolding, however, can solve this problem. Overmolding with polypropylene When overmolding with polypropylene, there are a few factors that must be considered to ensure that the end result meets all design requirements. The material's chemical and physical properties must match those of the substrate. In other words, the material cannot be molded directly onto stainless steel or a similar substrate. To get the best results from the overmolding process, you must first understand the function of the part. In most cases, the primary function is to provide a proper seal. However, it is also important to consider how the part will be exposed to UV light and harsh chemicals. Once you know where the part will be used, you can select a material that will not be damaged by harsh chemicals or UV light. To determine the ideal temperature range for overmolding with polypropylene, we first conducted a numerical simulation. In this simulation, we simulated a two-step molding process and determined the optimum mold temperature. This temperature was chosen so that the temperature gradients along the melt flow path would be the least. This information was then used to make design modifications.

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  • 2022.08.25

    Die test problem of automobile stamping die

    1. Pay attention to the selection of mold steelThis is the most important step to improve the quality of mold steel. Many factors need to be considered, including: the selection of mold steel materials, the usability and safety of mold steel structures, the machinability of mold steel parts, and the convenience of mold steel maintenance. These should be considered as thoroughly as possible at the beginning of the design.①The selection of mold steel materials should not only meet the customer's requirements for product quality, but also consider the cost of the material and its strength within the set period. , the main failure mode and other factors to select materials.② When designing the mold steel structure, try to make the structure as compact and easy to operate as possible, and ensure that the mold steel parts have sufficient strength and rigidity; when the mold steel structure allows, the corners of each surface of the mold steel parts should be designed as rounded transitions as much as possible. In order to avoid stress concentration; for the concave mold, cavity and part of the punch and core, the combination or mosaic structure can be used to eliminate the stress concentration; for the slender punch or core, appropriate protection measures should be taken in structure; Cold punching dies should be equipped with devices to prevent clogging of parts or waste (such as ejector pins, compressed air, etc.). At the same time, it is also necessary to consider how to reduce sliding fittings and frequent impact parts, which will cause wear and tear in long-term use. Influence on the quality of die steel.③In the design, it is necessary to reduce the scope of disassembly and assembly when a certain component is repaired, especially when the wearing parts are replaced, the scope of disassembly and assembly should be reduced as much as possible.2. Pay attention to the machining accuracy of the manufacturing processThis is also an important part of ensuring the quality of mold steel. The processing method and machining accuracy in the manufacturing process of mold steel will also affect the service life of mold steel.The accuracy of each component directly affects the overall assembly of the mold steel. In addition to the influence of the accuracy of the equipment itself, it is necessary to improve the processing method of the parts and improve the technical level of the fitter in the grinding and matching process of the mold steel to improve the mold steel parts. If the overall assembly effect of the mold steel does not meet the requirements, the probability of the mold steel moving in an abnormal state during the mold test will increase, which will have a great impact on the overall quality of the mold steel.In order to ensure that the mold steel has good original precision - the original mold steel quality, in the manufacturing process, first of all, it is necessary to reasonably select high-precision processing methods, such as EDM, wire cutting, CNC machining, etc. At the same time, attention should be paid to the quality of the mold steel. Accuracy inspection, including machining accuracy and assembly accuracy of mold steel parts, and comprehensive inspection of mold steel accuracy through mold trial acceptance. During inspection, it is necessary to use high-precision measuring instruments as much as possible. For those mold steel parts with complex surface and curved surface structures, if ordinary rulers and vernier cards cannot achieve accurate measurement data, then three-coordinate measurement is required. Instruments and other precision measuring equipment to ensure the accuracy of the measurement data.3. Surface strengthening forming partsThis can improve the wear resistance of the surface of the mold steel parts, thereby better improving the quality of the mold steel.For surface strengthening, different strengthening methods should be selected according to the mold steel used for different purposes. In addition, a technology called FCVA vacuum diamond coating developed in recent years can form a layer on the surface of the part that is extremely strong and combined with the matrix. A very smooth, uniform and dense protective film, this technology is especially suitable for the protective treatment of the surface of the mold steel, and it is also an effective method to improve the quality of the mold steel.4. Correct use and maintenance of moldsThe installation and debugging method of the mold should be appropriate, and the parameters of the CNC bending machine should be consistent with the design requirements and so on.When using the mold correctly, it is also necessary to carry out regular maintenance on the mold. The guide posts, guide sleeves and other parts with relative motion of the mold should be frequently filled with lubricating oil; for forging molds, plastic molds, die-casting molds and other molds, in Before each mold is formed, lubricant or mold release agent should be sprayed on the surface of the formed parts;Planned preventive maintenance of the mold and data processing in the maintenance process can prevent possible problems in the production of the mold and improve the efficiency of maintenance work.

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