The advantages and disadvantages of the use of formal and inverted standard mold frames

First, formal mold frame: the so-called formal standard mold frame structure is characterized by the concave mold installed on the lower mold base. Therefore, whether it is the blanking of the workpiece, punching, or some other processes, the workpiece or waste can be very convenient to fall into the waste hole on the punching table. Therefore, when designing the formal mold frame, it is not necessary to consider the flow of the workpiece or waste. Therefore, the design of the mold frame structure is very simple and very practical.

1, the advantages of formal mold frame structure

(1) Because of the simple structure of the mold frame, the manufacturing cycle of the mold frame can be shortened, which is conducive to the research and development of new products.

(2) The use and maintenance are more convenient.

(3) It is more convenient to install and adjust the gap between the convex and concave molds (relative to the inverted mold frame).

(4) The manufacturing cost of the mold frame is low, which is conducive to improving the economic efficiency of the enterprise.

(5) Because there is always a holding force during the whole drawing process, it is suitable for the stretching of non-rotating parts.

2, the shortcomings of the formal mold frame structure

(1) Due to the accumulation of workpiece or waste in the concave die hole, the group expansion force in the concave die hole is increased. Therefore, the wall thickness of the concave must be increased to improve its strength.

(2) Due to the accumulation of workpiece or waste in the concave die hole, under normal circumstances, the edge of the concave die must be processed with the blanking slope. In some cases, the opposite face of the cutting edge of the die (discharge hole) is also processed. Therefore, the production cycle of the die frame is extended, and the processing cost of the die frame is increased.

In the die, when choosing the die structure, the formal die structure should be preferred. Only when the formal mold structure can meet the technical requirements of the workpiece, other forms of mold structure can be considered.

Second, flip die frame: the so-called flip standard die frame structural characteristics refer to the punch installed on the lower die base, so we must use the pressure discharge device to unload the workpiece or waste from the punch. And its die is installed on the die base, so there is a problem of how to discharge the workpiece or waste parts in the concave hole from the hole.

1, the advantages of inverted mold frame structure

(1) Due to the use of pressure discharge device, the punching workpiece is smooth and the surface quality is good.

(2) Because the workpiece or waste is laid down from the concave die hole by the punching rod, the workpiece or waste is not accumulated in the concave die hole, which can reduce the expansion force of the workpiece to the hole. Thus, the wall thickness of the die can be reduced, the shape size of the die can be reduced, and the material of the die frame can be saved.

(3) Because the workpiece or waste is not accumulated in the die hole, it can reduce the wear of the workpiece or waste on the die edge, reduce the number of grinding of the die, and thus improve the service life of the die.

(4) Because the workpiece or waste is not accumulated in the die, it is not necessary to process the reverse face of the die (discharge hole). Can shorten the mold frame production cycle, reduce the mold frame processing costs.

(5) Because the blank holding force only acts before the plate blank is completely pulled into the concave die, it is suitable for the drawing of the rotating body.

2. Disadvantages of inverted mold frame structure

(1) The structure of the mold frame is more complex (relative to the formal mold frame).

(2) It is difficult to install and adjust the gap between the convex and concave molds (compared to the formal mold).

(3) The removal of the workpiece or waste (it is better to use compressed air to blow it away).

In the selection of die frame structure, only when the workpiece surface requires flat, the outline is more complex, the outline is asymmetrical, or the blank is thin when blanking, and the rotating body is stretched, the flip die frame structure is selected.