1. The choice of elastic force:
According to the calculated pressing force, select the number, model, and elastic pressure of each nitrogen spring. Generally speaking, the pressure of the nitrogen gas spring should be selected based on the calculated punching pressure plus an increase of 15%-20%, which is more in line with the actual situation.
(1) When the mold wears out, there will be gap changes. Changes in process parameters such as cutting edge bluntness, inconsistency of mold thickness and mold plate deformation resistance will cause changes in the deformation resistance of the workpiece, so the deformation resistance should be left in the design.
(2) When the nitrogen gas spring is inflated, the high-pressure gas will inevitably have throttling loss, which will make the elastic force float down.
(3) The life of the nitrogen gas spring is very long. After a period of use, the high-pressure nitrogen gas will leak to a certain extent, causing the spring pressure to drop slightly.
2. Selection of quantity:
It should be based on the needs of the trip, combined with the mold structure and the focus point, so that the mold will not be unbalanced when it is working, and it must be convenient to adjust the mold. In this way, the nitrogen gas spring can have a sufficient life span in use.
3. Selection of boost ratio:
It can be selected according to the characteristic curve of the nitrogen spring and the requirements of the stamping process to determine the model of the nitrogen spring. Especially when the working force is required to change steadily, or the working force is basically constant and the initial force is relatively large, it is more important to determine the boost ratio.
4. Choice of itinerary:
Regardless of the process, when choosing the nitrogen gas spring, we always hope that the total height of the gas spring should not be too high, so as to avoid instability and too complicated structure when installing on the mold. The larger the stroke, the higher the price of the gas spring. This is particularly important for independent nitrogen gas springs.
If the stroke is really large due to process requirements, it is recommended to use the nitrogen spring seat plate system, which can reduce the height of the mold and improve the stability and reliability of the nitrogen spring. Sometimes in order to be safe and avoid accidents, when choosing a nitrogen gas spring, it is necessary to increase the safety stroke of 3-5mm.
