Nut stamping parts release external forces on plates, amorphous materials, pipes and aluminum profiles by stamping machines and abrasive tools, resulting in plastic shape changes or separation, thereby obtaining steel parts (stamping parts) that require samples and specifications Forming production processing stamping dies and forging are the same plastic deformation production processing (or working pressure production processing), collectively called forging. The key to the material of the stamping die is hot and cold pressing of thick steel plates and steel chains. The key of stamping die is classified according to the processing technology, which can be divided into two types: separated process flow and molding process flow.
1. Basic principles and characteristics of stamping dies
1. The basic concept of cold die
Metal or non-metallic materials cause deformation under external force. When the external force exceeds the yield limit of the raw material, plastic deformation begins. If the working pressure increases again and the ultimate compressive strength of the raw material is exceeded, the metallic or non-metallic material will just start to crack and separate. The cold die uses this characteristic of the metal material to separate or deform the raw materials at room temperature, and then obtain the product specified by the required appearance and accuracy.
2. The advantages of cold die
1) Under the impact of a high-speed punch, complex products can be obtained.
2) After production and processing, the product has high precision, stable specifications and good exchangeability.
3) Under the condition that the consumption of raw materials is not large, products with light weight, good compressive strength, good rigidity, smooth and beautiful surface can be obtained.
4) The utilization rate of raw materials reaches 75% ~ 85%.
5) Most of the commonly used raw materials are thick plates or tube materials. It is easy to choose professional and automated machinery. Hundreds of high-speed punch presses per minute.
6) The actual operation is simple and the labor efficiency is low.
7) Under many manufacturing standards, products are low cost.
3. The defect of the cold die is that the regulations on the grinding tools are higher, and the die processing is more complicated, which is not suitable for small and large batch production.
Second, the rationality of stamping parts processing
1. Key countermeasures to reduce manufacturing costs
1) Improve the rationality level of the processing technology.
2) Design scheme Each steel piece is produced and processed separately.
3) Control the cost by improving the automation technology and high speed of the whole process of stamping die.
4) Cost control by means of increasing the utilization rate of raw materials.
5) Improve the level of stamping die, reduce the process flow, and increase the service life of abrasive tools.
3. Process flow of stamping parts
1. According to the overall deformation characteristics of raw materials, the stamping die process flow is divided into two types and five basic deformation methods.
1) Separation process: the raw material is separated under external force, and the ground stress of the deformed part exceeds the strength limit of the raw material.
2) Plastic deformation process flow: Under the external force of the thick plate, the in-situ stress of the deformed part exceeds the yield limit of the raw material, but when the strength limit is not reached, only plastic deformation is caused to obtain a certain shape and specifications.
4. Five deformations of stamping die process
1. Cutting and cold stamping: There is no closed type or non-closed type to separate the raw material part from another part. Methods that fall into this category include blanking, punching machines, trimming, breaking, cutting, and wounds.
2. Bending: the flat thick plate is changed into a bent piece, and the shape of the bent piece is further changed. There are bends, curling and distortion.
3. Injection molding: the flat blanks are stamped into hollow parts as required, or the specifications of the hollow parts are further changed.
4. Forming: using various deformation of parts to flatten and change the appearance of products or blanks. Attributable to forming deformation are wave forming, reverse side, necking, convex belly, rounding, and plastic surgery.
5. Three-dimensional suppression: the volume is allocated and the raw materials are transferred to change the appearance design of the blank or the aspect ratio.
In order to improve production efficiency during the whole process of stamping parts, the process flow of multiple basic deformation methods can be combined to form a new process flow, which is called a composite process flow.
