Precision Stamping Processes vs Other Processes

The precision stamping process is essential.

Here we take you through the precision stamping process and how it differs from other processes.

What is the precision stamping process

Precision stamping is a material processing method developed based on the common stamping process. It is the process of obtaining precision stamped parts by improving the guiding accuracy, reducing the gap between the convex and concave dies, and increasing the reverse pressure and the V-ring crimping circle, resulting in the process of precision stamping or the combination of precision stamping and other forming processes under strong three-way compressive stress conditions.

Comparison of the precision stamping process with other processes

Comparison with die-casting

The die-casting process combines pressure, speed, and time using three main elements: machine, die, and alloy. Used in the thermal processing of metals, the presence of pressure is the main feature of the die casting process that distinguishes it from other casting methods… Pressure casting is a less cutting-free special casting method developed relatively quickly in recent metalworking processes. It is the molten metal in high pressure and high speed under the casting filling and in high-pressure crystallization solidification to form the casting process. High pressure and high speed is the main feature of pressure casting. The commonly used pressure is tens of megapascals, the filling speed (inner gate speed) is about 16 to 80 m/s, and the time for the metal liquid to fill the mold cavity is extremely short about 0.01 to 0.2 seconds.

Both die-casting and stamping are methods of processing and forming parts, but die-casting uses pressure to fill the mold with a liquid metal to obtain the same part as the mold; stamping uses the function of the mold to remove certain parts of the solid metal to obtain the required part.

Comparison with ordinary stamping

Precision stamping requires higher precision for stamped parts In the process of processing and production, stamping rolls or forming, the technical support of suitable precision presses, dies, materials, lubricants, etc., must be considered and is more demanding.

Ordinary stamping requires less precision for stamped parts and has specific market demand. The thickness of the base material is thicker and does not require processes such as cutting, chipping, and stretching; the stamped materials are plates, tubes, etc. When a single volume of the product is not required, ordinary stamping is sufficient to meet the requirements.

Comparison with injection molding

The injection molding process mainly includes four stages: filling – holding pressure – cooling – demoulding, etc. These four stages directly determine the molding quality of the product, and these four stages are a continuous process. These four stages directly determine the quality of the product, and these four stages are a complete and continuous process.

1.Filling stage

The filling is the first step in the whole injection molding cycle, and the time is counted from when the mold is closed to when the mold cavity is filled to about 95%. Theoretically, the shorter the filling time, the higher the molding efficiency, but in practice, the molding time or injection speed is subject to many conditions.

2.Pressure-holding stage

The role of the holding pressure stage is to continuously apply pressure to compact the melt and increase the density of the plastic (densification) to compensate for the shrinkage behavior of the plastic.

3.Cooling stage

In injection molding molds, the design of the cooling system is very important. This is because the molded plastic product can only be cooled and cured to a certain rigidity after demolding to avoid deformation of the plastic product due to external forces. As cooling time accounts for approximately 70% to 80% of the entire molding cycle, a well-designed cooling system can significantly reduce molding time, increase injection molding productivity and reduce costs. A poorly designed cooling system can increase molding times and costs; uneven cooling can further cause warping and deformation of plastic products.

The injection molding cycle consists of mold closing time, filling time, pressure holding time, cooling time, and demoulding time. The temperature of the plastic product during the molding stage should be cooled to a temperature below the heat deflection temperature of the plastic product to prevent warpage and deformation caused by residual stresses or external forces during demoulding.

4.Demoulding stage

Demoulding is the last part of the injection molding cycle. Although the product has been cold-set, molding still impacts the quality of the product. Improper molding methods may lead to uneven forces during demolding and deformation of the product during ejection. There are two main types of demoulding: top bar de-molding and stripper plate demoulding. The mold design should be based on the structural characteristics of the product to choose the appropriate release method to ensure product quality.

The difference is that the precision stamping process produces precision metal stamping products. In contrast, the plastic process produces plastic products, and the structure of the mold is also different. The basic principle of forming the goods is also different; plastic molds are injection molded and then cooled and formed while stamping molds are extruded from a specified thickness of raw material.

In terms of the role of the mold, the stamping die is a mass production machine for metal products. The raw materials used are generally iron, copper, or aluminum profiles, while the plastic die is for plastic products, and the raw materials used are also plastic.

How to improve the precision stamping process

Stamping is a highly productive and low-material consumption processing method. The stamping process is suitable for the production of larger quantities of parts products, easy to achieve mechanization and automation, with high production efficiency; at the same time, stamping production can not only strive to achieve less waste and no waste production but also even in some cases have edge residues, can also be fully utilized.

1.a good material edge analysis of the drop die and determination of the size of the drop die drop line using multiple rounds of release sampling.

2.CAE analysis of the drawing die to determine whether the process profile is reasonable and to compensate for the risk of cracking and wrinkling.

3.trimming die through the process improvement to prevent the scrap from sliding, trimming scrap knife accumulation of iron chips, increase the amount of knife entry, to facilitate the scrap slide.

4.flap forming die process analysis of flap height, cracking, and wrinkling production process compensation.

5.process merging for stamping parts reduces processes and improves production efficiency.

6.Make process checks on the production process to confirm that the product operates according to the work instructions.

Particular attention should be paid to the fact that each production process needs to be carried out following the work instructions and that the production of stamped parts should be combined with the process as far as possible to improve production efficiency. The quality of the stamping product determines the quality of the final product. A good stamping process analysis is required to improve the quality of the stamping product, and a good stamping process can improve production efficiency and quality.

Notes on precision stamping process

1.the number of processes of precision stamping parts mainly depends on the complexity of their structural shape and the number of bending angles, relative position, and bending direction.

2.the number of processes for precision stamped parts is related to the nature of the material, the height of the drawing, the number of drawing steps as well as the diameter of the drawing, the thickness of the material, and other conditions, which the calculation of the drawing process can only determine.

3.For precision stamped parts with simple shapes, single process molds are used. For complex-shaped workpieces, the structure or strength of the die is limited, so multiple stamping processes are required.

4.When the section quality and dimensional accuracy of precision stamped parts are high, additional trimming processes can be considered after the blanking process, or an immediate precision blanking process can be used.

5.The number of processes should also be determined by the existing mold-making capacity and the condition of the stamping equipment of the company.

6. To improve the stability of the precision stamping process, it is sometimes necessary to increase the number of processes to ensure the quality of the precision stamped parts.

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