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Abstract
Punching die has been widely used in industrial production.In the traditional industrial production,the worker work very hard,and there are too much work,so the efficiency is low.With the development of the science and technology nowadays,the use of punching die in the industial production gain more attention, and be used in the industrial production more and more.Self-acting feed technology of punching die is also used in production, punching die could increase the efficience of production and could alleviate the work burden，so it has significant meaning in technologic progress and economic value.
The article mainly discussed the classification,feature and the developmental direction of the pnnching technology. Elaborated the punching components formation principle, the basic dies structure and the rate process and the principle of design; and designed some conventional punching die:the die for big diameter three direction pipe which solved the problom of traditional machining,the drawing and punching compound die with float punch-matrix,the drawing and cutting compound dies with unaltered press,the compound die for the back bowl of the noise keeper,the design of the compound die which could produce two workpieces in one punching,the bending die for the ring shape part ,the bending die which used the gemel ,automate loading die for cutting, the drawing,punching and burring compound dies with sliding automated loading,the punching die for the long pipe with two row of hole,the drawing die for the square box shape workpiece and the burring die for the box shape workpiece.The punching dies that utilized the feature of the normal punch shaped the workpiece in the room temperature,and its efficiency and economic situation is excellent.
The dies here discussed can be easily made,conveniently used, and safely operated.And it could be used as the reference in the large scale production of similar workpieces.
