How is the squeezing process carried out?

1, Material preparation
The first step in the extrusion process is material preparation. Choosing appropriate raw materials is the foundation for ensuring the quality of extruded products. Purchase raw materials from the market that meet the required standards based on the material, shape, size, and performance requirements of the product. For example, in metal extrusion, commonly used raw materials include aluminum, copper, steel, etc; In plastic extrusion, thermoplastic materials such as polyethylene and polypropylene are often used.
Raw materials usually require pre-treatment before entering the extruder. This includes steps such as cleaning, drying, cutting, and heating. Cleaning can remove impurities and oil stains from the surface of raw materials, avoiding contamination of the product; Drying can reduce the moisture content in the raw materials and prevent the formation of bubbles and shrinkage during the extrusion process; Cutting is the process of processing raw materials into sizes suitable for feeding into the extruder; Heating is used to bring the raw material to the appropriate extrusion temperature, improving its plasticity and flowability.
2, Mold design
Mold is a key component in the extrusion process, which determines the shape and size of the product. The design of the mold needs to be based on the specific requirements of the product, including the shape, size, material selection, and cooling system of the mold.
The shape and size of the mold must accurately match the shape and size of the required product. Meanwhile, the selection of mold materials is also crucial, as they must be able to withstand the high temperature and pressure generated during the extrusion process while maintaining sufficient hardness and wear resistance. Common mold materials include hard alloys, tool steel, and stainless steel.
In addition, the cooling system of the mold is also an important part of mold design. During the extrusion process, the mold will be heated by high-temperature metal or plastic, resulting in an increase in mold temperature. If the mold temperature is too high, it will affect the quality of the product and the service life of the mold. Therefore, it is necessary to design a reasonable cooling system to control the mold temperature within an appropriate range.
3, Squeezing operation
Squeezing operation is the core link of the squeezing process. In this stage, the raw materials are fed into the extruder, and through the extrusion effect of the mold, the desired shape and size of the product are formed.
Squeezing machines are usually composed of a main engine, heating system, transmission system, and control system. The host is the main part of the extruder, which includes key components such as the extrusion cylinder, extrusion rod, and mold. The heating system is used to heat the raw materials to the appropriate extrusion temperature. The transmission system is responsible for driving the extrusion rod to perform reciprocating motion, achieving the extrusion of raw materials. The control system is used to monitor and adjust various parameters during the extrusion process, such as temperature, pressure, speed, etc.
During the extrusion process, the raw material is first fed into the heating system of the extruder and heated to the appropriate extrusion temperature. Then, the raw materials are fed into the extrusion cylinder and enter the mold cavity through the extrusion action of the extrusion rod. Under the squeezing effect of the mold, the raw material undergoes plastic deformation and gradually fills the mold cavity. Finally, when the extrusion rod exits the mold, the product is released from the mold, completing the extrusion process.
4, Subsequent processing
After extrusion, the product needs to undergo a series of subsequent treatments to improve its quality and performance. This includes steps such as cooling, cutting, straightening, and surface treatment.
Cooling is the process of reducing a product from a high temperature state to room temperature. This helps to eliminate residual stresses inside the product and improve its hardness and strength. Cutting is the process of cutting a product into the desired length or shape. Straightening is used to correct the bending or twisting phenomenon that may occur during the extrusion process of the product. Surface treatment is aimed at improving the appearance quality and corrosion resistance of products, such as spraying, electroplating, etc.
In addition, for certain extruded products with special requirements, additional post-processing is required, such as heat treatment, aging treatment, etc. Heat treatment can further improve the hardness and strength of the product, while aging treatment can eliminate residual stresses inside the product, improve its stability and service life.