What is the cause of delayed cracking in the processing of stainless steel drawing parts?

1. Delayed cracking of austenitic stainless steel. (such as 200 series, represented by 304, 300 series, etc.)

The delayed cracking of austenitic stainless steel is mainly determined by its own structure, and the degree of work hardening of austenitic stainless steel is relatively large. After stretching, in addition to the residual internal stress generated by cold working, the austenite structure also undergoes martensitic transformation at the mouth. To prevent cracking of the mouth, it is necessary to eliminate residual stress and martensitic structure, so that it can undergo phase transformation at high temperature. Austenitic stainless steel takes 304 as an example, and the annealing temperature is 1010-1050 degrees Celsius. Generally, in order to avoid the overall annealing deformation of the stretched part, only the mouth of the stretched part is annealed, and the relatively fast one is high-frequency annealing.

2. Delayed cracking of ferritic stainless steel. (For example, 400 series stainless steel represented by 430, commonly known as stainless steel)

Ferritic stainless steel does not change after stretching, and product cracking is mainly caused by residual stress. In order to ensure safety, from experience, for cylindrical deep-drawn parts, when the aspect ratio is greater than or equal to 0.8 and the diameter is greater than or equal to 300, annealing treatment is required. Of course, if cracking occurs when the aspect ratio is less than 0.8, annealing should be arranged immediately.

When using stainless steel or ferritic stainless steel materials, the use of stamping and drawing oil can reduce the breakage rate of the product and reduce the cost. The lubrication state of stamping is a mixed state of fluid lubrication and boundary lubrication. If only mineral oil is used, the strength of the oil film will not meet the requirements, and the oil film will be easily broken, which will cause metal-to-metal contact to produce sintering. The use of oily agents can make up for this deficiency. One end of the oily agent molecule contains polar groups such as carboxyl group, hydroxyl group and ester group. These polar groups can chemically or physically adsorb oily agents and form a solid lubricating film on the metal surface, thereby improving lubricating performance.

However, when the friction surface temperature rises to a certain temperature, the molecular arrangement of the oily agent adsorption film will be destroyed and the lubricating effect will be lost. At this time, the boundary lubricating film covering the surfaces of the two metals disappears, resulting in direct contact between the metals. As the direct contact area increases, the frictional energy also increases, resulting in an increase in temperature and a tendency to occur so-called sintering. In this case, the additive used to prevent direct contact between the two metal surfaces is an extreme pressure agent, even at elevated temperatures. Extreme pressure agent (EP) is a kind of boundary lubricating film that uses the high temperature generated on the friction surface to chemically change itself, generate shear force on the friction metal surface, and play an effective protective role.

Stretching of stainless steel hardware, equipment, molds and stretching oil are key factors. Otherwise, no matter how good the personnel and technology are, it is difficult for a clever woman to cook without rice, and cannot make high-quality products.

Metalworking Manufacturing Statistics: The design life of drawing equipment is about 10 years, which is caused by factors such as the equipment itself, overuse and improper maintenance. In the process of metal drawing, improper selection of drawing oil will lead to accelerated wear and tear of many equipment, and some will be paralyzed in a few years, which directly affects the operation of the whole plant and cannot maximize benefits.

What should be paid attention to when processing sheet stainless steel drawing parts?

1. Stamping characteristics of stainless steel sheet

1. High yield point, high hardness, obvious cold work hardening effect, and prone to cracks and other defects.

2. The thermal conductivity is worse than that of ordinary carbon steel, resulting in large deformation force, punching force and deep drawing force.

3. The plastic deformation is severely hardened during deep drawing, and the sheet is easy to wrinkle or fall off when stretched.

4. The deep drawing die is easy to produce adhesion tumor, which leads to serious scratches on the outer diameter of the part.

5. It is difficult to achieve the expected shape during deep drawing.

After reading the stamping characteristics of stainless steel sheet, let’s take a look at how to solve the problem of deep drawing of stainless steel sheet. The editor believes that these problems are determined by the characteristics of stainless steel itself, which are mainly affected by the following five factors:

1. Raw material properties

2. Die structure and stamping speed

3. Mold material

4. Stamping lubricant

5. Process design

And the quality of the sheet will also affect the stamping performance, so the materials we purchase should be regular and meet the standards. For hard materials, an annealing operation should be performed before stamping to increase processability.

The above is about the processing of thin-plate stainless steel tensile parts. Have you learned it? If you don’t understand anything, you can contact the webmaster of this site, and we can communicate together!

How to calculate the mold processing of metal drawing parts?

First, learn to stretch the expansion

The expansion of the stretched parts can be divided into two types: software expansion and manual expansion. For the expansion of general cylindrical parts, it is generally feasible to use software and manual expansion. For complex curved parts, irregular products, Then we can use software to expand, for example: one-step expansion of UG software, or expansion with AUTOFORM software is possible. Its principle is to assume that the material does not change in volume without thinning. principle.

Then the computer expansion is based on the finite element analysis and calculation to obtain an expansion result, which is usually the result under ideal conditions and has a great reference value. Manual expansion is the radius of expansion obtained by mathematical calculation, so manual expansion can only be a conventional method of mathematical calculation.

2. Learn to calculate the stretching parameters

The biggest problem that troubles us in the stretching calculation is how many times a piece can be pulled out, and how to determine the size of each time? Masters who have done stretching molds are generally confused about this piece. If you can calculate, it will be like clearing the clouds and seeing the sun. A very important parameter in the stretching parameters is the stretching coefficient M, which is a ratio to put it bluntly, and is an empirical parameter summed up by predecessors in long-term practice. Tensile coefficient M = finished product size d / blank size D, when this coefficient is less than the ultimate tensile coefficient of a certain material, then we assess that the product cannot be pulled out at one time, that is, there is a risk of rupture. Of course, the stretched parts are also closely related to the forming R of the product and the size of the blank holder. There are many parameters involved. For details, you can consult the relevant stretching data for details.

3. Process layout

The process design is to calculate the stretched size according to the result of the stretching calculation, but the calculation is quite complicated each time the height is stretched. In order to obtain the stretched height more intuitively and easily, the CAD software can be used for simulation calculation. Adjust the height value of the stretch a few times to determine the correct height value for each stretch, still following the principle of constant volume. Of course, expressing computation in words is a difficult process. It takes practice to really master it.

The last thing I want to tell you is that stretching is not as difficult as you think. Find experienced people to learn the method, then many problems will be solved easily.

The above is the relevant content about the calculation of mold processing for metal drawing parts. For those who are not familiar with the field, mold processing is more complicated, and the failure rate is high. People in the industry can be said to be at their fingertips. Hope the above content is helpful to readers

BYD Geely engine water temperature sensor shell

BYD Geely engine water temperature sensor shell

1. Manufacturing process: Brass coil, deep drawing, deep drawing, redrawing, reshaping, flat head chamfering

2. Scope of application: BYD, Geely Automobile, Sinotruk, Jiefang Xichai, Yuchai, Weichai water temperature sensor copper shell outer cover universal

3. Stamping material: brass h63

4. Surface treatment: special degreaser for copper, special brightener for copper, special color retention agent for copper

5. Dimensions: Outer diameter is 8.8, inner diameter is 7.9, and height is 21.8. In addition, the dimensions can be customized according to your company’s requirements, and the unit price is negotiable.

6. Product features: no burrs on the end face, flat head chamfering, parallel and vertical cut surfaces, bright appearance

7. Quality: The production quality is strictly controlled, and the products are fully inspected before they are shipped. The products must be inspected before leaving the factory to ensure that every process meets the requirements and quality problems.

Quality comes from details. In order to let you buy better products, we strive to improve every detail. From accessories to craftsmanship, we are devoted to the pursuit of quality by Balford people.

Renault GM Volvo Water Temperature Sensor Housing

Renault GM Volvo Water Temperature Sensor Housing

1. Manufacturing process: Brass coil, deep drawing, deep drawing, redrawing, reshaping, flat head chamfering

2. Application range: Renault, GM, Volvo, Xichai, Yuchai, Weichai engine water temperature sensor copper shell cover

3. Stamping material: brass h63

4. Surface treatment: special degreaser for copper, special brightener for copper, special color retention agent for copper

5. Dimensions: Outer diameter 25.5, inner diameter 24.5, height 18.4, in addition, the dimensions can be customized according to your company’s requirements, and the unit price is negotiable.

6. Product features: no burrs on the end face, flat head chamfering, parallel and vertical cut surfaces, bright appearance

7. Quality: The production quality is strictly controlled, and the products are fully inspected before they are shipped. The products must be inspected before leaving the factory to ensure that every process meets the requirements and quality problems.

Quality comes from details. In order to let you buy better products, we strive to improve every detail. From accessories to craftsmanship, we are devoted to the pursuit of quality by Balford people.

Fiat temperature sensor housing water temperature sensor housing

Fiat temperature sensor housing water temperature sensor housing

1. Manufacturing process: brass coil, deep drawing, deep drawing, redrawing, extruding steps, flat head chamfering

2. Scope of application: Fiat, Sinotruk, Jiefang, Xichai, Yuchai, Weichai water temperature sensor, copper shell, universal cover

3. Stamping material: brass h63

4. Surface treatment: special degreaser for copper, special brightener for copper, special color retention agent for copper

5. Dimensions: Outer diameter 18, inner diameter 17.15, height 27.5, in addition, the dimensions can be customized according to your company’s requirements, and the unit price is negotiable.

6. Product features: no burrs on the end face, flat head chamfering, parallel and vertical cut surfaces, bright appearance

7. Quality: The production quality is strictly controlled, and the products are fully inspected before they are shipped. The products must be inspected before leaving the factory to ensure that every process meets the requirements and quality problems.

Quality comes from details. In order to let you buy better products, we strive to improve every detail. From accessories to craftsmanship, we are devoted to the pursuit of quality by Balford people.

What is the reason for the wrinkling of stamping and drawing die products?

1. Factors and solutions that affect the wrinkling of stamping parts

1. The effect of stretching depth

The distribution of flow resistance along the die opening is directly related to the draw depth. On the concave and convex position, excessive stretching depth will lead to uneven distribution of deformation resistance and the formation of wrinkles. This should be avoided as much as possible.

2. Adjust the blank holder force

If wrinkles are evenly generated around the workpiece, it is judged that the holding force is insufficient, and the wrinkles can be eliminated by gradually increasing the blanking force. When stretching conical and hemispherical parts, most of the material is in air at the beginning of the stretching. Since the side wall is prone to wrinkling, it is not only necessary to increase the blank holder force, but also to increase the radial tensile stress in the plate by adding pick-up ribs and eliminate wrinkles.

3. Influence of die fillet radius

The radius of the die fillet is too large, and the blank flows into the die and passes through the die fillet, resulting in bending deformation, and the bending resistance is small. The lower the bending resistance, the easier it is to cause wrinkling. The smaller the bending deformation of the die radius, the greater the bending resistance and the smaller the possibility of wrinkling, but it is easy to cause parts to crack and pull.

Through the accumulation of practical experience in mass production, it is proved that the main reasons for the wrinkling of stamping parts are the accumulation of materials during the stretching process and the excessive speed of some materials. When formulating a practical solution, the above aspects should be considered to adjust the corresponding mold mechanism to achieve good results.

2. Measures and methods to prevent wrinkling of stamping parts

The method to prevent wrinkling is to ensure that the die can press the material during the drawing process of the metal stamping part to ensure the flow speed of the sheet. When the stamping part is stretched, the material flows too fast, which will cause wrinkles; on the other hand, the material flows too slowly, which will cause stamping cracks.

1. Use a reasonable pressing device

When the pressing device is used, the pressing device presses the deformed part of the blank, and aligns the pressing force to prevent the flange part from arching and causing wrinkles. The size of the pressing force should be appropriate. The pressing device is divided into two types: elastic pressing and rigid pressing. The elastic device is suitable for shallow drawing, and the rigid device is suitable for deep drawing.

2. Reasonable use of drawbeads

Setting drawbeads on the binder surface is an effective method to adjust and control the deformation resistance. Drawbeads can well adjust the flow of materials, so that the material flow resistance of each part during the drawing process is uniform, so that the amount of material flowing into the cavity is suitable for the needs of the workpiece, and the phenomenon of wrinkling and cracking is prevented. For curved stretched parts with complex shapes, especially those with smaller flanges, drawbeads should be set to increase the radial tensile stress of stretching to control wrinkling;

The location of the drawbead is where the radial tensile stress is smaller, that is, the location where the sheet is easy to flow. For parts with small flanges, in order to set the draw bead, some materials (process supplementary materials) can be added appropriately, and this part is removed when trimming. For drawing parts with large difference in drawing depth, draw beads should be set in the part with a small amount of feed, so as to prevent excessive material from being pulled into the mold cavity to prevent wrinkling.

3. Analysis of the causes of wrinkling of tensile parts

There are many reasons for wrinkling during stretching, the main reasons are as follows:

1. The drawing depth of the stamping part is too deep, which causes the sheet material to flow too fast during the feeding process and form wrinkles.

2. During the stretching process of the stamping part, the R angle of the die is too large, so that the punch cannot press the material during the stretching process, causing the sheet to flow too fast to form wrinkles.

3. The pressing of the stamping parts is unreasonable, the pressing ribs are too small, and the position is incorrect, which cannot effectively prevent the sheet material from flowing too fast and forming wrinkles.

How to remove the burrs of metal stamping parts?

1. How to remove burrs on metal stamping parts

1. Manual removal of burrs: If the number of stamped products is small, a more feasible method is to remove them manually. This kind of quality is better, but it is not suitable for high-volume processing removal.

2. Electrolytic deburring: This method is more efficient and has better quality, but the equipment cost is too high, and general small enterprises cannot afford it.

3. Vibration grinding to remove burrs (gear burrs), this method has high efficiency and good quality.

4. For the stamping parts after heat treatment, the burrs can be removed by shot peening, which can also eliminate the surface stress of the material;

5. Use air guns with various shapes of gun tips to remove burrs. This method is very effective and works more efficiently.

6. Use electrochemical deburring. If self-made equipment, the cost is not high, economical, efficient and practical.

2. The removal of burrs on metal stamping parts by the metal stamping factory mainly revolves around these four points

1. Outer diameter: When performing metal stamping processing, chamfering is performed with a lathe.

2. Edge: Use file, oil stone, sandpaper, sharpening stone.

3. Welding slag: Vibrating welding slag tools can remove brittle burrs.

4. Holes: Use a chamfering knife or the front end of a drill with a larger diameter to deburr the holes of the metal stamping parts.

5. It can also be polished, polished, sandblasted, etc., depending on the workpiece.

Production requirements for precision metal drawing parts

What should be paid attention to when producing precision stretched parts?

1. The shape of the precision stretched product should be as simple as possible, and it should be stretched as much as possible in one processing.

2. For parts with complex appearance that need to be stretched many times, on the premise of ensuring the quality, the appearance should be allowed to have traces that may be produced during the processing.

3. Under the premise of ensuring the assembly requirements of the drawing die, the side wall of the drawing part should be allowed to have a certain slope.

4. The distance from the edge of the hole on the bottom or flange to the side wall of the precision stretch is appropriate.

2. What are the technical requirements for the processing of metal drawing parts?

In daily life, you can see many metal stretch products, such as stainless steel thermos cups, stainless steel bottle caps, stainless steel basins for kitchens, stainless steel small bowls, etc., all of which are stainless steel stretch products.

Compared with the metal stretching process, the shape of the stretched part is related to the simplicity and complexity of the stretching process. Simple shapes will be stretched into shape at a time. If the process of stretching the product is complicated, it needs to be stretched several times. Of course, under the premise of ensuring product quality, the number of deep drawing should be increased as much as possible, and the interval time of the drawing process should be extended. During the stretching process, stretch marks may appear on the surface of the product. Under the premise that the product is qualified, there is a certain slope on the side after stretching to ensure that the product size, whether it is internal or external, can achieve better stretching quality.

Another important aspect of hardware stretching is choosing the right lubricant.

The mold used for metal drawing parts is generally composed of punch, die and blank holder. The gap between the punch and the die is greater than the thickness of the sheet metal. Since the diameter of the die is smaller than the diameter of the blank, the material undergoes plastic flow during stamping and drawing. One part increases the height of the part, and the other part increases the thickness of the barrel wall. The stretching process is due to the internal interaction of the metal caused by the force of the material, resulting in internal stress between the elements in the metal. Under the action of internal stress, a strain state occurs, which causes the material to undergo plastic deformation, and is pulled into the die from time to time to become a cylindrical workpiece. The modification point of the stamping and drawing process is the transformation from a large section of the material to a cylindrical workpiece with a small section. In this process, the surface of the material and the surface of the die must be in contact to generate friction. In order to reduce the friction coefficient and reduce the extrusion force, a stretching oil with good performance must be used. The complex stretching process and lubricants also play a very important role. effect.

What are the advantages of cold stamping?

First, the advantages of cold stamping

The production process of the hardware processing factory for processing metal stamping parts is the cold stamping process. Cold stamping is based on the plastic deformation of metal. Dies on a press are used to apply downward pressure to a metal sheet or strip, separating or plastically deforming the material to achieve the desired shape, size and properties. For advanced stampings, this pressure treatment method is cold stamping.

Since the cold stamping process is a plastic deformation process, the surface of the material is not damaged, so the surface quality of the stamped parts is good, and the appearance is smooth and beautiful. This is a variety of surfaces, such as painting on the surface of stamping parts or various electroplating phosphating treatments. Provide convenience for processing, which is the main advantage of cold stamping hardware.

After the plastic sheet is deformed, the internal structure of the metal is improved, increasing the strength of the stamped part. There are two main advantages of stamping.

The third advantage of hardware cold stamping is that the dimensional accuracy of the stamped parts after processing is higher, which is opposite to the size of the die parts and has good interchangeability. Routine assembly and use requirements are met without further processing.

Whether the shape structure is a pure part or a complex hardware part, or how many sets of molds are required, it is mass-produced and can replace the high cost of molds.

Cold stamping is a processing method with high efficiency (ie high productivity) and low consumption (ie high material utilization): the cold stamping process is suitable for the production of large-scale parts, easy to realize mechanization and automation, and has high production efficiency. At the same time, cold stamping can not only achieve low-waste or no-waste production, but also make full use of leftovers without causing waste.

Under the simple stamping of the press, various parts with complex shapes that are difficult to be processed by other processing techniques can be obtained.

Since most stamping parts are made of sheet metal, their surface quality is good, which provides convenient conditions for subsequent surface treatment processes (such as electroplating, painting, etc.).

Stamping can obtain high strength, high rigidity and light weight parts with low consumption.

Volkswagen Audi Skoda water temperature sensor housing coolant temperature sensor housing

Volkswagen Audi Skoda water temperature sensor housing coolant temperature sensor housing

1. Manufacturing process: brass coil, deep drawing, deep drawing, redrawing, extruding steps, flat head chamfering

2. Scope of application: Volkswagen Audi Skoda Cummins, Sinotruk, Jiefang Xichai Yuchai Weichai engine coolant temperature sensor copper shell cover

3. Stamping material: brass h63

4. Surface treatment: special degreaser for copper, special brightener for copper, special color retention agent for copper

5. Dimensions: Outer diameter is 8.88, inner diameter is 7.98, and height is 30.7. In addition, the dimensions can be customized according to your company’s requirements, and the unit price is negotiable.

6. Product features: no burrs on the end face, flat head chamfering, parallel and vertical cut surfaces, bright appearance

7. Quality: The production quality is strictly controlled, and the products are fully inspected before they are shipped. The products must be inspected before leaving the factory to ensure that every process meets the requirements and quality problems.

Quality comes from details. In order to let you buy better products, we strive to improve every detail. From accessories to craftsmanship, we are devoted to the pursuit of quality by Balfoed people.

renault nissan water temperature sensor housing

renault nissan water temperature sensor housing

1. Manufacturing process: Brass coil, deep drawing, deep drawing, redrawing, reshaping, flat head chamfering

2. Scope of application: Renault-Nissan, Sinotruk, Jiefang, Xichai, Yuchai, Weichai water temperature sensor, copper shell, outer cover, universal

3. Stamping material: brass h63

4. Surface treatment: special degreaser for copper, special brightener for copper, special color retention agent for copper

5. Dimensions: Outer diameter 25.1, inner diameter 24.5, height 19.4, in addition, the dimensions can be customized according to your company’s requirements, and the unit price is negotiable.

6. Product features: no burrs on the end face, flat head chamfering, parallel and vertical cut surfaces, bright appearance

7. Quality: Strictly control the production quality, the products are fully inspected before they are shipped, and the products must be inspected before leaving the factory to ensure that every process meets the requirements and quality problems.

Quality comes from details. In order to let you buy better products, we strive to improve every detail. From accessories to craftsmanship, we are devoted to the pursuit of quality by Balford people.

Mercedes Benz car coolant temperature sensor housing water temperature sensor housing

Mercedes Benz car coolant temperature sensor housing water temperature sensor housing

1. Manufacturing process: Brass coil, deep drawing, deep drawing, redrawing, reshaping, flat head chamfering

2. Scope of application: Mercedes-Benz BMW, Sinotruk, Jiefang Xichai, Yuchai, Weichai coolant temperature and water temperature sensor, copper shell, outer cover, universal

3. Stamping material: brass h63

4. Surface treatment: special degreaser for copper, special brightener for copper, special color retention agent for copper

5. Dimensions: Outer diameter 18, inner diameter 17.15, height 30.1, in addition, the dimensions can be customized according to your company’s requirements, and the unit price is negotiable.

6. Product features: no burrs on the end face, flat head chamfering, parallel and vertical cut surfaces, bright appearance

7. Quality: The production quality is strictly controlled, and the products are fully inspected before they are shipped. The products must be inspected before leaving the factory to ensure that every process meets the requirements and quality problems.

Quality comes from details. In order to let you buy better products, we strive to improve every detail. From accessories to craftsmanship, we are devoted to the pursuit of quality by Balford people.

What are the requirements for material properties of automotive stamping parts?

First, the advantages of cold stamping

The production process of the hardware processing factory for processing metal stamping parts is the cold stamping process. Cold stamping is based on the plastic deformation of metal. Dies on a press are used to apply downward pressure to a metal sheet or strip, separating or plastically deforming the material to achieve the desired shape, size and properties. For advanced stampings, this pressure treatment method is cold stamping.

Since the cold stamping process is a plastic deformation process, the surface of the material is not damaged, so the surface quality of the stamped parts is good, and the appearance is smooth and beautiful. This is a variety of surfaces, such as painting on the surface of stamping parts or various electroplating phosphating treatments. Provide convenience for processing, which is the main advantage of cold stamping hardware.

After the plastic sheet is deformed, the internal structure of the metal is improved, increasing the strength of the stamped part. There are two main advantages of stamping.

The third advantage of hardware cold stamping is that the dimensional accuracy of the stamped parts after processing is higher, which is opposite to the size of the die parts and has good interchangeability. Routine assembly and use requirements are met without further processing.

Whether the shape structure is a pure part or a complex hardware part, or how many sets of molds are required, it is mass-produced and can replace the high cost of molds.

Cold stamping is a processing method with high efficiency (ie high productivity) and low consumption (ie high material utilization): the cold stamping process is suitable for the production of large-scale parts, easy to realize mechanization and automation, and has high production efficiency. At the same time, cold stamping can not only achieve low-waste or no-waste production, but also make full use of leftovers without causing waste.

Under the simple stamping of the press, various parts with complex shapes that are difficult to be processed by other processing techniques can be obtained.

Since most stamping parts are made of sheet metal, their surface quality is good, which provides convenient conditions for subsequent surface treatment processes (such as electroplating, painting, etc.).

Stamping can obtain high strength, high rigidity and light weight parts with low consumption.

What should be paid attention to in the processing of precision stamping parts

The five elements that must be paid attention to in the production of precision stamping parts are people, machines, materials, methods, and rings. To put it bluntly, they are people, machines, materials, methods, and environments. These five elements are very important for the processing of precision stamping parts. Next, the editor of Zhejiang Baifudu will make a specific introduction.

1. Five elements that need to be paid attention to when processing precision stamping parts

1. People: Among the five major dangers, the quality depends on the mastery of people, the characteristics of civilization, personality, attention, spirit, eyesight, and mentality. A person who has not received training will undoubtedly make a poor quality product.

2. Equipment: the accuracy, reliability and durability of mechanical equipment. If our high-speed punching machine has poor precision, will the products we produce have many problems with poor appearance and specifications? The quality of the mold will be damaged.

3. Raw materials: The quality of incoming materials and their reliability will immediately jeopardize the quality of the product. As the saying goes: if you throw in by mistake, you don’t get out.

4. Method: The accuracy, consistency and reliability of production and processing methods.

5. Natural environment: The quality of the storage environment and the office environment will damage the quality of the goods and the mentality and fighting spirit of the staff. In a messy office environment, it is impossible to make good fine stamping parts.

The above content is shared here. If you want to know more about precision stamping parts processing, please follow us, Zhejiang Balford Electromechanical Co., Ltd., located in Huzhou, Zhejiang, we are a professional consumer manufacturer of precision metal stamping, stretch forming and precision injection molding.