What is the cause of the tensile die strain and what is the solution?

The cause of the injury

1. Between the workpiece and the mold

Adding a film such as PVC between the mold and the molding material can sometimes solve the problem of workpiece strain. For the production line, the film can be continuously provided by the mechanism. For the stamping equipment of periodic production, each workpiece needs to add a layer of film, which affects the production efficiency. This method is generally expensive and also produces a large amount of waste. For small batches of large workpieces Production is desirable.

2. Raw materials for forming workpieces

By surface treatment of the raw material, such as phosphating, spraying or other surface treatment, a non-metallic mold layer is formed on the surface of the material to be formed, which can greatly reduce or eliminate the strain of the workpiece. This method is often more expensive. high, and requires the addition of additional production equipment and increased production processes.

3. Mould

By changing the convex and concave ink materials of the mold or surface treatment of the convex and concave molds, the secondary properties of the contact between the finished material and the convex and concave molds are changed.

Second, the solution

1. There are many ways to solve the problem of surface strain of workpiece and mold convex and concave mold. For different situations, the application method needs to be selected according to the size of the workpiece and the load, the production batch, the type of processing material, etc.

2. Using cemented carbide as the mold material, the chemical vapor phase of the convex and concave surface of the mold is deposited. TD is usually a cladding treatment. TD coating treatment is cost-effective.

Well, the above is what is the solution to the cause of the stretching die strain? I hope the above content can help readers.

How to choose stamping and drawing die materials?

1. Selection of drawing die materials

1. The selection of stamping and drawing die materials should consider the batch production of the workpiece. If the batch is small, there is no need to choose a mold material with a long life; the material of the stamping workpiece should also be considered, and the mold materials suitable for different materials are also different.

2. For stamping and drawing dies, wear resistance is an important factor determining the life of the die. The wear resistance of steel depends on the state of hard spots such as carbides and the hardness of the matrix. The higher the hardness of the two, the higher the number of carbides, the better the wear resistance.

3. The advantage of poor wear resistance of commonly used stamping die steel is carbon tool steel – alloy tool steel – base steel – high carbon and high chromium steel – high speed steel – steel bonded carbide – carbide.

4. The selection of the drawing die material must consider the thickness, shape, size and precision requirements of the workpiece.  

Well, the above is related to the selection of stamping and drawing die materials. I hope the above content can help readers.

What requirements do stamping and drawing dies need to meet when drawing?

1. Requirements for stamping and drawing dies

1. Under the condition of ensuring normal use, the designed stamping and drawing die should reduce the dimensional accuracy level and surface roughness level as much as possible, which is conducive to product exchange, reducing waste and ensuring product quality stability.

2. The design of the stamping and drawing die must meet the use and technical performance of the product, and it is easy to assemble and repair.

3. The design of stamping and drawing dies must be conducive to improving the utilization rate of metal materials, reducing the variety and specifications of materials, reducing the consumption of materials as much as possible, using low-cost materials where possible, so that the parts are as free of waste as possible and reduce Scrap blanking.

4. The design of stamping and drawing dies should be as beneficial as possible to the processing of existing equipment, process equipment and technological processes, and to prolong the service life of stamping dies.

5. The design of stamping and drawing dies must be simple in shape and reasonable in structure, which is conducive to simplifying the structure of the die and simplifying the number of processes, that is, to complete the entire part processing with less and simple stamping processes, reducing other methods, which is conducive to stamping operations and facilitates organization and realization Mechanized and automated production to increase labor productivity.

6. Stamping and drawing dies can produce good products. Therefore, in the design of stamping and drawing dies, the design must be strictly followed to avoid the design and loss of stamping and drawing dies!  

What are the forms of stamping and drawing dies?

1. The form of stamping and drawing dies

1. Formal features

The surface of the punched workpiece is relatively flat to provide conditions for our subsequent processing.

2. Flip-chip features

It is very convenient to operate and has a wide range of applications, but the flatness of the workpiece surface is relatively poor, and the tension on the punch and die is relatively large, so the wall thickness of the punch and die should be strictly controlled to avoid insufficient strength.

After analysis, it is very inconvenient to operate the workpiece if it adopts a formal-type conforming mold. In addition, the workpiece has higher straightness requirements and relatively low workpiece accuracy requirements, so it is easy to operate. Considering the simplicity of mold manufacturing and other aspects, it was decided that the second, third and fourth deep drawing should be inverted, and the first deep drawing should be formal.

Through the above introduction, we can understand that there are two forms of stamping and drawing dies, which are formal and inverted, and different forms should be selected according to different production processes.

What is the reason for the die processing of the drawing die?

During the processing of the drawing die, if the die clamping is not flexible enough, or there is a stuck situation, then the production should be stopped immediately, and the main reason for the stuck die should be found out and troubleshoot. Otherwise, it may expand the failure, resulting in mold damage.

First, the main reasons for the card mold are:

The mold is poorly guided and tilted. And there are foreign objects in the template, so that the template cannot be flatly attached; there is a problem with the strength design of the mold or uneven force. It will lead to the deformation of the mold, such as the hardness and thickness of the mold base and the template are too small, and it is very easy to be deformed by external force; the mold position is not installed correctly, and the positioning error of the upper and lower molds is too poor. Or the precision of the press is too low, causing the mold to interfere; the strength of the punch is low, and the position of the large and small punches is too close, which makes the lateral force of the mold unbalanced. At this time, the strength of the punch should be increased, and the guidance and protection of the stripper plate should be strengthened.

The above has explained the reasons for the occurrence of card molds in the processing of drawing molds, and different reasons will have different solutions, so we need to solve the problems in a targeted manner.

How to choose the positioning method of stamping and drawing dies?

1. Blocking pin

The function of the stopper pin is to use the strip to overlap or punch the outline to limit the feeding distance of the strip. There are three common types of stopper pins in national standards: fixed stopper pins, movable stopper pins, and initial stopper pins. The fixed stopper pin can be easily installed on the bottom die and can be used to control the feeding distance of the strip. It features simple structure and convenient processing. Because it is installed on the die, the mounting hole may also weaken the strength of the die, and the commonly used structures have similar circular and hook-shaped retaining pins. Active stop pins are often used in flip-chip composite molds. The start stop pin is used to start positioning in the progressive die.

Second, the guide pin

Guide pins are often used in conjunction with stop pins in progressive dies to minimize positioning errors and ensure the relative position dimensional accuracy requirements of holes and shapes. When there is no hole suitable for the guide pin on the part, for the progressive die with too many processing steps and high part accuracy requirements, process holes should be set in the vacancies on both sides of the strip to guide the pin. Use straightening strips. At this time, the guide pin is fixed on the punch fixing plate or the elastic pressure stripper.

Three, side edge

In the progressive die, the side edge is often used to control the step distance of the strip, so as to achieve the purpose of accurate positioning. The side edge is actually a punch for cutting edge material, using the edges on both sides of the side edge to cut off the material on both sides of the strip to form a step. After the strip is cut off part of the edge material, the width can continue to be fed to the die, and the feeding distance is the cut length. When the material is sent to the step formed after cutting, the side edge stopper prevents the material from continuing to feed, and a new feeding step can be formed only after the next work of the mold.

Fourth, the positioning plate and positioning nails

Positioning plates and positioning pins are all components used for positioning a single blank to ensure the relative position accuracy of the front and rear processes or the position accuracy requirements of the inner hole and outer contour of the workpiece.

5. Control of feeding direction

The feeding direction of the strips is the guide plate with the strips on the side, and the feeding is guided along the designed feeding direction to make the strips close to the guide plate on one side to ensure the accuracy of the feeding, and a side pressure device can be used. Since the stamping and drawing die adopts the cover-shaped semi-finished product that is drawn out of the sheet for the first time, the material can be positioned by the blank holder in the die.

The editor added: The correct position must be accurately guaranteed by relying on its own positioning parts. Due to the different forms of blanks and the different structures of the stamping and drawing dies used, there are many types of positioning parts. The design should be selected according to the form of the blank, the structure of the stamping and drawing die, the tolerance of the parts, and the production efficiency.

Through the above introduction, let’s briefly introduce that we have a good understanding of the positioning of the stamping and drawing die, and the selection of its positioning method is selected according to the positioning parts, which I hope we can understand.

How to solve the rust of the drawing die

First, the cause of mold rust

There are three main reasons for mold rust:

1. The product of the decomposition of the molding material.

2. The resurgence of molds.

3. Sweaty hands.

Second, the relevant analysis of mold rust

1. The products (gas, residue) decomposed by the forming material are also very common to the corrosion of the mold. In order to prevent the mold from rusting, we generally use chrome plating on the mold cavity, but the chrome plating treatment cannot completely solve the problem. Because decomposing organisms also corrode the deep part of the pin hole. And these places are places where there is no way to plate them.

2. When the mold is cooled below the moisture regain point, the moisture in the air will regain moisture on the mold surface and produce water droplets, which will lead to rust.

3. Solve the problem of mold rust

1. Short-term: wipe the surface of the mold cavity with a cloth by hand. Fully dry the molding material, reduce the temperature of the barrel, and prevent the material from decomposing. When temporarily stopping molding, spray rust inhibitor into the mold cavity, and then close the mold.

2. Long-term: Turn the product material into a material that will not be corroded by decomposition products. Materials that are easily decomposed include PVC, POM, EVA, PC, and foam. Since the decomposition products have a corrosive effect on the mold, if the plastic raw material cannot be replaced, the mold should be chrome-plated. When the mold is not used for a long time, apply a layer of butter to the outside of the mold and the movable parts.

What are the differences in the manufacture of stamping dies?

First, the manufacturing difference of stamping dies

1. Different smelting process

The smelting process of Dachang material is electric furnace smelting, out-of-furnace refining, and vacuum degassing. The chemical composition of the steel in this process is accurately controlled, the gas content in the steel is low, and the steel purity is high. The materials of small factories are generally mixed scrap and furnace materials in the intermediate frequency furnace, and the flat steel ingots are directly poured. The chemical composition deviation of this process is large, the impurities in the steel are large, and the gas content is high, resulting in more shrinkage cavities and internal cracks in the finished product, which seriously affects the processing performance of the steel.

2. The rolling process is different

Dachang’s steel ingots are forged into billets and then rolled into products. During the rolling process, multiple rolling mills and multiple deformations are used for continuous rolling. Small mills are steel ingots that are directly rolled back and forth by a single rolling mill. The ingot deformation is small, the rolling ratio is small, the internal microstructure is uneven, and the non-metallic inclusion particles are large. It is directly manifested as the local “saw and drill” of the material.

3. Different appearance quality

Since the material of the big factory is continuously rolled, and the number of deformations is large, the precision of its appearance and size is high, and the two sides are approximately right angles. Because the production process of the small factory material is all controlled manually, its appearance size deviation is large, the thickness and width tolerance is large, the flat steel fillet is large, and the cross-section deviates from the rectangle.

4. Different heat treatment methods for finished products

After the material of the big factory is finished, the global annealing process is adopted to ensure that the carbide grade in the steel is not greater than grade 4, and the uniformity of hardness is ensured. Small factory materials adopt general softening annealing process, even natural cooling, which cannot guarantee the uniformity of carbide grade and hardness in steel.

5. The effect is different

Due to the different production processes, it directly affects the use effect of materials. First of all, the material size deviation of the small factory is large, and the straightness is relatively poor, resulting in a large enough machining allowance during processing, otherwise it cannot be processed. Secondly, due to the uneven hardness of materials in small factories, it is difficult to process and punch holes, and the processing efficiency is low. After processing, the workpiece is easily deformed, and even the mold is scrapped.

What are the maintenance methods of hardware drawing molds?

1. Maintenance method of metal drawing die

The punch of the metal drawing die is relatively less frequently repaired, and it is broken due to failure. Therefore, in order to ensure that the metal drawing die has sufficient rigidity, the die and the unloading plate should be guided by the small guide posts on the four fixed punch fixing plates to ensure the uniformity of the punch gap, and multiple small punch guides. , The discharge screw on the discharge plate should adopt the same height sleeve to ensure the smooth punching.

The bottom of the effective cutting edge of the concave die is completely hollowed out or vacuum adsorption is used to ensure smooth discharge of punching waste; in addition, the punch edge of the metal drawing die should be ground regularly to ensure its sharpness; when the metal drawing die is not in use , You should apply anti-rust oil to the working part in time, but it should be noted that when you use the hardware stretching mold next time, you should first clean it, and then use oil-absorbing paper to test the flushing until the oil is absorbed cleanly, otherwise it will affect the plating quality. When moving the metal drawing die, it should be light, steady and slow to avoid shock and severe vibration. When storing, there should be a fixed position to control the air humidity, and it should not be placed directly on the shelf or metal stretching die.

The above are the two brothers’ methods for the maintenance of metal stretching molds. Correct use and maintenance can not only guarantee the service life of the metal drawing die, but also the quality of the final product. Therefore, it is still very necessary. If you have any questions about the maintenance of metal drawing dies, you can consult our manufacturers!

There are three points in PAX’s deep-drawing strength

Production and Technology

Several commonly used stamping die finishing methods

1. Method of finishing stamping die
1. Manual grinding and polishing

Traditional mold surface processing methods mainly rely on the experience and technology of operators. Manual polishing is time-consuming and inefficient. Some complex surfaces or joints are difficult to handle.

2. Mechanical finishing, grinding

Commonly used grinding equipment includes surface grinders, internal and external circular grinders and tool grinders. To ensure that, CNC machining is generally used. Choose the appropriate type of grinding machine according to the shape of the different parts, choose the surface grinder for plate parts, and use the internal and external cylindrical grinder or tool grinder for the curved and turning surface parts.

3. Machining, CNC milling machine

Among them, the surface processing method of stamping die not only has fast processing efficiency, but also has good processing quality. Except for the inner acute angle cavity and the extremely narrow cavity, it can be competent in other aspects. It has become the mainstream process of stamping die processing abroad, and my country is also actively developing it.

4. There are also some non-mechanical finishing methods, such as: ultrasonic machining, EDM polishing, laser finishing, chemical polishing, electrochemical polishing, etc.

Stamping die processing manufacturers also need to have more characteristics of stamping dies and the difficulty of machining accuracy. Choosing the appropriate finishing method can save costs and effectively improve production efficiency. Zhejiang Baifudu Electromechanical is a mold processing manufacturer that produces stamping dies, continuous stamping dies, metal stamping dies, continuous dies, school tool dies, etc. Friends who need to process dies are welcome to contact us!

According to the processing method of the product, what types of stamping dies can be divided into?

1. What types of stamping dies can be divided into?

According to different product processing methods, molds can be divided into five categories: punching and shearing molds, bending molds, drawing molds, forming molds and compression molds.

1. Punching and shearing die: The work is completed by shearing. Commonly used forms are shearing dies, blanking dies, punching dies, trimming dies, edge-forming dies, punching dies, and punching dies.

2. Bending die: It is a shape that bends the flat blank into an angle. Depending on the shape, precision and production volume of the parts, there are many different forms of dies, such as ordinary bending dies, cam bending dies, curling dies Dies, arc bending dies, bending punching dies and twisting dies, etc.

3. Drawing mold: Drawing mold is to make flat blank into seamless container with bottom.

4. Forming die: refers to changing the shape of the blank by various local deformation methods, and its forms include protrusion forming, curl forming die, necking forming die, hole flange forming die, and round edge forming die.

5. Compression mold: use strong pressure to flow and deform the metal blank into the desired shape. Types include extrusion dies, embossing dies, imprinting dies and end press dies.

Here we share the classification of processing methods of stamping die products. If you have any other questions, you can also consult us! We are a manufacturer of stamping molds, continuous stamping molds, metal stamping molds, continuous molds, school tool molds and other mold processing manufacturers. Feel free to contact us!

What are the assembly steps of the stamping die?

1. Assembly steps of stamping die

1. Select the assembly reference parts. When assembling, first select the datum part. The principle of selecting the reference parts is determined according to the dependence of the main parts of the mold in the processing process. The main components that can be used as assembly reference components are punch, die, punch, guide plate and fixed plate.

2. Component assembly. Component assembly refers to the assembly work in which the mold connects two or more components into a component according to the specified technical requirements before assembly. Such as mold base assembly, punch, die, fixed plate assembly, unloading, assembly of various components of the thrust mechanism, etc. These parts should be assembled according to the function of each part to ensure the assembly accuracy of the entire stamping die.

3. Overall assembly. Final assembly is the process of combining parts and components into a complete stamping die. Before final assembly, the assembly reference parts should be selected and the assembly sequence of the upper and lower molds should be arranged.

4. Adjust the gap between the convex and concave die. When assembling the mold, the uniformity of the punch and die gap must be strictly controlled and adjusted. After adjusting the clearance, tighten the screws and pins.

The methods of adjusting the gap between convex and concave molds mainly include light transmission method, measurement method, gasket method, coating method, copper plating method, etc.

5. Inspection and debugging. After the stamping die is assembled. The assembly accuracy must be guaranteed, the specified technical requirements must be met, and the function of each part of the mold must be checked according to the technical conditions for mold acceptance. Die tryouts are carried out under actual production conditions, and adjustments and corrections are made according to the parts produced by the die. After the mold test is qualified, the mold processing and assembly are basically completed.

Do you now have an understanding of the assembly steps of the stamping die? I hope this article helps you! We are a manufacturer of stamping dies, continuous stamping dies, metal stamping dies, continuous dies, school tool dies, etc. We are also a die manufacturer integrating design, production, processing, sales and service. You can contact us if necessary. !

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Various shapes of parts: -drawings
Standard or special gasket on-lid-lid– the lid and surface of the gauge– many metal mechanical partsIndustrial products of various sizes:Standard, Standardized or Drawing. Thickness: between 0.2mm and 6mm (depending on material).

different materials Stamping:

– Cold Rolled Sheet, Hot Rolled Sheet, Galvanized Sheet
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aluminum
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Why do metal stamping dies need to try out?

After stamping and producing qualified samples, the performance and forming conditions of the mold have mastered the methods and rules of the product parts during the stamping process, which provides a reliable process design basis for the mass production of the mold. In the production of cold stamping dies in metal stamping parts factory, it is difficult to accurately calculate the size and shape of the blank before the blank is deformed, such as deformation, stretching, forming, cold extrusion and other product parts with complex shapes or high precision requirements. In order to obtain more accurate blank shape dimensions and material standards, qualified parts can only be determined by repeatedly debugging the mold.

In die design and process design, it is difficult to determine some process dimensions by calculation methods, such as complex protrusions of deep drawing die, rounded corners of concave die, geometry and size of certain parts. The metal stamping parts factory must carry out test punching and trimming at the same time, and the shape and size of the parts can only be determined after the qualified parts are punched out. After debugging, the problems, debugging and solutions exposed in the process, mold design and manufacturing are fed back to the relevant design and process departments to provide reference for the next design and manufacturing, and improve the level of mold design and processing. The metal stamping parts factory verified the quality and precision of the mold through the mold test, which provided the basis for future production.

The above is why metal stamping dies need to be tested before use. I hope it helps you. If you want to know more about stamping die, you can also pay attention to our website, we will update the information of stamping die from time to time!