U-shaped stainless steel spring

Cold forming principle of U-shaped stainless steel spring
As a common spring shape, U-shaped stainless steel springs are widely used in electrical, automotive, construction, industrial equipment and other fields. It usually has good corrosion resistance and elasticity, and can maintain stable performance in harsh environments. The key to the manufacturing process of U-shaped springs lies in the cold forming process, through which high-precision and high-efficiency manufacturing can be achieved to ensure product quality.
Cold forming refers to a processing method that applies pressure to metal materials through mechanical equipment at room temperature to cause plastic deformation and finally obtain the desired shape. Compared with hot forming, cold forming does not require a heating process, so it has the advantages of energy saving, reduced oxidation, and good surface quality. In addition, cold forming can significantly improve the mechanical properties of materials, especially for products with high strength and high precision requirements such as springs. Cold forming is the most common production method.
For stainless steel springs, the cold forming process is especially important. Stainless steel materials have high strength and corrosion resistance, but also because of their high hardness and strong toughness, process control during the cold forming process has become particularly critical. During the cold forming process, stainless steel materials are precisely processed by CNC spring forming machines and other equipment, relying on strong extrusion, bending and torsion forces to gradually form a U-shaped structure.
Cold forming steps of U-shaped stainless steel spring
Material selection and preparation
Before cold forming, you first need to select a suitable stainless steel material. Commonly used stainless steel materials include 304, 316, etc., which have good corrosion resistance and strength. The selection of materials not only determines the spring performance after molding, but also affects the operability during processing.
In actual operations, raw materials usually exist in the form of wire rods. Before materials enter the molding machine, they need to be cleaned and surface treated to remove oxide layers or stains that may affect molding accuracy. This step is very important because the surface condition of stainless steel will directly affect the molding quality. A clean surface can reduce the friction and stress concentration of the material during the molding process, thus improving the product qualification rate.
Cold forming equipment
Modern spring manufacturing usually relies on high-precision CNC spring forming machines, such as the Japanese and Taiwanese precision CNC equipment used by us at Ningbo Chaoying Spring Industry & Trade Co., Ltd. This type of equipment can be controlled by computer programs to accurately adjust various processing parameters to ensure that the size and shape of each spring meets the design requirements.
The forming of U-shaped springs usually requires the use of a multi-axis forming machine, which uses pressing and bending operations in multiple directions to gradually shape the stainless steel wire during the forming process. Equipment automation and precision control technology can reduce human operating errors and improve production efficiency.
Key parameters during the molding process
In the cold forming process of U-shaped stainless steel springs, the control of several key parameters is crucial:
Forming force: Stainless steel has a relatively high hardness and requires a large forming force during the bending process. If the forming force is insufficient, the material will not bend into the intended shape; while excessive forming force may cause the material to crack or break. Therefore, the adjustment of the forming force must accurately match the mechanical properties of the stainless steel.
Bending angle: The two ends of the U-shaped spring need to form a precise bending angle, which determines the spring's resilience and performance in the application. CNC equipment can accurately adjust the bending angle, but attention still needs to be paid to controlling the springback effect, especially when processing highly elastic materials such as stainless steel.
Wire diameter size: The wire diameter of the U-shaped spring directly affects its strength and elasticity. If the wire diameter is too large, it will cause molding difficulties, while if the wire diameter is too small, the spring performance may be insufficient. Therefore, it is necessary to accurately calculate the design requirements of the spring before molding, and ensure the accuracy of the wire diameter through strict equipment calibration during the processing process.