Problems that should be paid attention to when choosing special-shaped springs in spring design:

How to choose a special-shaped spring? To solve this problem, it is usually necessary to consider the elastic pressure, stroke, the number of special-shaped springs and the pressurization ratio of the special-shaped spring.

(1) Selection of spring pressure: According to the calculated punching pressure, select the number and type of special-shaped springs and the elastic pressure of each special-shaped spring. Generally speaking, the elastic pressure of the special-shaped spring should be selected according to the calculated punching pressure, plus an increase of 15%-20%, which is more in line with the actual situation. First, as the die wears, the clearance changes. Changes in process parameters such as blunt edges, as well as the inconsistency between the thickness of the mold and the deformation resistance of the template, will cause changes in the deformation resistance of the workpiece, so there should be room for deformation resistance in the design. Secondly, when the special-shaped spring is inflated, the high-pressure gas will inevitably have a throttling loss, which will cause the elastic force to float downward. Third, the special-shaped spring has a long life. After a period of use, there will be some leakage in the high-pressure profile, resulting in a slight decrease in elastic pressure.

(2) Selection of the number of special-shaped springs: According to the line requirements, combined with the mold structure and key points, the mold will not be offset during work, and the mold adjustment must be convenient. In this way, the alien spring can have enough life to use.

(3) Selection of the special-shaped spring pressurization ratio: The type of special-shaped spring can be determined according to the characteristic curve of the special-shaped spring and the stamping process requirements. Especially when the working force needs to change steadily, or the working force is basically unchanged, and the initial force is large, it is more important to determine the assist ratio.

(4) Stroke selection of special-shaped spring: no matter which process is used, when selecting special-shaped spring, we always hope that the total height of special-shaped spring is not too high, so as to avoid instability when installed on the mold, the structure is too complicated, and the larger the stroke , the higher the price of the special-shaped spring, which is especially important for the independent special-shaped spring. If the process requires and the stroke is really large, it is recommended to use the special-shaped spring seat plate system, which can reduce the height of the mold and improve the stability and reliability of the special-shaped spring. Sometimes in order to be safe and avoid accidents, it is necessary to increase the safety travel by 3-5 mm when choosing a special-shaped spring.