The working principle of the stamping machine is that the punch moves repeatedly (usually up and down), while the cushion part is fixed. The cushion part is fixed on the base and connected to the base through the frame and connecting rods. The driving part of the punch (the driving part is usually mounted on the upper part called the crown) is connected to receive the applied pressure.

Main technical parameters of stamping:
The main technical parameters of the crank press comprehensively reflect the equipment's technological capabilities and applicable scope, as well as related productivity and other indicators. Mainly includes the following contents:

(1) Nominal pressure: the nominal pressure of the crank press refers to the maximum force allowed on the slider when the slider is a certain distance before the bottom dead center or when the crank rotates to a certain angle before the bottom dead center. (this specific distance is often called the nominal pressure stroke, and the specific angle is called the nominal pressure angle). When the nominal pressure stroke or nominal pressure angle range is exceeded, the force that the slider can withstand is lower than the nominal pressure.

(2) Slider stroke: slider stroke refers to the distance from the top dead center to the bottom dead center of the slider. The stroke of some crank presses is adjustable to meet the needs of different types of molds.

(3) Number of slider strokes (min-1): the number of slider strokes refers to the number of times the slider reciprocates from top dead center to bottom dead center and back to top dead center per minute.

(4) Closing height and mold installation height: closing height refers to the distance from the bottom surface of the slider to the surface of the workbench when the slider is at the bottom dead center. When the connecting rod adjusting device adjusts the slider to the highest position of bottom dead center (the connecting rod is adjusted to the shortest position), the closing height reaches the maximum, which is called the maximum closing height, when the connecting rod adjusting device adjusts the slider to the lowest position of bottom dead center (when the connecting rod is adjusted to its longest position), the closing height reaches the minimum, which is called the minimum closing height. The difference between the two is the closing height adjustment amount. The mold installation height refers to the distance from the bottom surface of the slider to the surface of the workbench pad when the slider is at the bottom dead center. The difference between the closing height and the molding height is the thickness of the backing plate. The backing plate on the crank press is generally not removed during operation.

(5) The size of the workbench (backing plate) and the bottom surface of the slider: the size of the crank press workbench (backing plate) and the bottom surface of the slider mainly affects the installation of the mold and the discharge of waste materials and workpieces. Generally, small presses are connected to the press slide through the die handle. Large and medium-sized presses are equipped with T-slot fixed molds on the bottom surface of the backing plate and slider.

Stamping equipment selection:

The selection of stamping equipment is an important part of process design. It is directly related to the reasonable use and safety of the equipment, and is also related to whether the stamping process can be successfully completed and to ensure product quality, mold life, production efficiency and cost. important question. Generally, the equipment type and tonnage are reasonably selected based on factors such as the nature of the stamping process, the size of the stamping force, the mold structure type, the mold closing height and contour size, and the production batch, combined with the actual equipment conditions of the unit.

When determining the specifications of the press, the following principles should generally be followed:

(1) The nominal pressure of the press is not less than the pressure required for the stamping process. When bending or drawing, the pressure curve should be within the safe zone of the allowable load curve of the press slider.

(2) The stroke of the press slider should be sufficient to obtain the required size in terms of the height of the workpiece, and the workpiece can be smoothly removed from the mold after stamping.

(3) The closing height of the press, the size of the workbench and the size of the slider should meet the correct installation of the mold. In particular, the closing height of the press should be adapted to the closing height of the die.

(4) The number of strokes of the slider of the press should meet the requirements of productivity and material deformation speed.