1. Selection of spring pressure of nitrogen gas spring
When applying nitrogen gas spring technology in cold stamping die design, the first problem encountered is the choice of elastic pressure, what type of gas spring to choose, and how strong is the gas spring to meet the requirements of the stamping process and solve such problems. , Usually need to consider three aspects:
(1) The elastic pressure of the nitrogen gas spring.
(2) The number of nitrogen gas springs.
3) The boost ratio of the nitrogen gas spring.
2. How to choose the nitrogen spring stroke?
The stroke of the nitrogen gas spring should meet the requirements of the stamping process. Different stamping processes require different stroke sizes. The blanking and separation process requires a large elastic pressure and a small stroke; the drawing process generally requires a relatively large stroke. As a nitrogen spring with a blank holder force function, the characteristic curve of the nitrogen spring is required to be relatively gentle. During the drawing process, the blank holder force is basically There is little change in the upper part, that is, the elastic pressure is basically kept constant; for ejection and unloading, sufficient strength and stroke are required;
In the bending and flanging process, the initial force is usually required to be large in order to be able to press the workpiece and prevent the workpiece from sliding or moving during the bending process. Generally speaking, the stroke is also required to be relatively large. In either case, the total height of the nitrogen gas spring should not be too high to avoid instability and avoid the complicated structure of the gas spring when it is installed on the mold and increase the cost of tooling. If the gas spring is installed in the upper mold, Regardless of whether it is the top plate or the blank holder, there must be a gap to ensure that the nitrogen gas spring works smoothly; sometimes for safety reasons, to avoid accidents, consider increasing the size of the gas spring by 3-5 mm when designing and selecting the gas spring. Safe travel, so as to ensure the normal operation of nitrogen for a long time.
3. How to choose the structure of nitrogen gas spring?
When using nitrogen gas springs in mold design, it is first necessary to determine the structure of the gas spring. There are several forms to choose from: independent nitrogen gas spring, gas spring seat plate type, pipeline connection type, etc. These basic structural forms have their own characteristics and a certain range of applications. They need to be considered comprehensively according to the stamping process requirements of the parts, the structural form of the mold, the equipment used, the working environment, the working conditions, the cost of the mold, and the convenience of adjustment and maintenance. select.
