About the drawing die used by different punches
Single action punch drawing die
Tensile die for single action punch refers to the tensile die used in eccentric or crankshaft punch with only one slide motion. There are many kinds of drawing die according to the process.
4. Reverse drawing die
Reverse drawing die refers to a drawing die in which the punch is pushed down from the bottom of the blank in reverse and the blank surface is turned over so that its inner surface becomes the outer surface. Reverse stretching is mostly used for multiple stretches after the first stretch. The parts that are stretched out are not easy to wrinkle. It is suitable for deep conical or hemispherical parts (such as lampshades), and sometimes it is also suitable for the stretching of cylindrical parts. The tensile coefficient of backward drawing is 10~15% smaller than that of forward drawing, and the tensile force is larger than that of forward drawing, and the wall of the die is thinner. The minimum diameter of the drum after reverse drawing can reach (30 ~ 60)t, and the minimum fillet radius of reverse drawing can reach (2~6)t. Therefore, reverse drawing is a very economical processing method, and the quality of the parts is also very good.
The positive and negative drawing die of hemispherical parts is completed under one stroke of the punch press. Under the condition that there is no double action punching, the fixed holder is used to press the edge. This kind of structure is suitable for ordinary punch stretching, after stretching the spherical parts without wrinkles, accurate size.
For the reverse drawing die with guide post, the semi-finished product is positioned in the concave die hole, and then the blank is pressed by the convex and concave die, and then the punch enters the convex and concave die hole, and the workpiece is drawn and formed in reverse. The parts are played by the rod and the pushing plate from the die.
5. Stretch the trimming die
Drawing edge cutting die is a compound punching die which is formed by drawing and cutting edge at the same position of the die under one stroke of the punch press. The die is suitable for shallow drawing parts with small tensile thickness and low height.
6. Multilayer die drawing die
When the output is large, in order to improve labor productivity, often put two or three times the tensile die on a die base, the use of a tensile punch through a number of different positions of the die for continuous tensile forming, to complete a number of tensile processes.
