How to choose the right punch

How to choose the right punch

Punching machine is a kind of equipment commonly used in industrial production in recent years. It has various types and complete models, and the types and models of products are different, and their use characteristics and applicable places are also different. Therefore, many users who do not understand the product comprehensively are choosing There are often many doubts when buying. To this end, the editor introduces the following shopping tips for everyone, you can learn about it.

1. Choose the right model

Under normal circumstances, from small metal blanking parts, bending parts or shallow drawing parts, it is recommended to choose an open punch. The elastic deformation of the open-type equipment body will destroy the uniform distribution of the gap of the die, affect the accuracy of the stamping product, and reduce the life of the die. However, its fuselage is open on three sides, easy to operate, easy to install molds, feeders, and automatic mold changing devices to achieve automated production, and the price is economical. Therefore, open punches are recommended for the stamping of small and medium-sized parts.

For large and medium-sized or high-precision stamping products, gate-type and dual-axis equipment should be used. For special stamping processes such as leveling, correction bending, and shaping, equipment with higher strength and rigidity should be selected.

2. Choose the right specification

The selection of specifications needs to involve the four major aspects of equipment tonnage, large closing height, speed and table size:

(1) Selection of tonnage

The tonnage of the selected punch must be greater than the actual stamping pressure during stamping production, and it must be ensured that the part load curve does not exceed the allowable load curve. Usually the tonnage selection principle: when punching and correcting bending, the large punching force is not more than 80% to 90% of the tonnage; when Deep Drawing, the large drawing force is not more than 50% to 60% of the tonnage; when shallow drawing , The large drawing force is not more than 70% to 80% of the tonnage; when punching bending or punching deep drawing composite stamping, the tonnage value should be determined according to the specific situation and the allowable load curve of the machine tool used; for thicker For stamping parts, not only the allowable pressure of the punch, but also the power must be considered.

(2) Selection of the countertop

The punch table should be determined according to the size of the actual installed mold. If the mold is large, the size of the work table can be increased according to customer needs.

(3) Selection of a large closing height

When selecting, the closing height of the Stamping Die should be between the large closing height and the small closing height of the punch.

Since the connecting rod will be shortened after it is worn out, and the closing height of the stamping die will be reduced when the mold is repaired in the future, the height of the stamping die when designing the stamping die is generally close to the large installation height of the punching machine.

(4) Selection of stroke and speed

This is usually determined according to the actual stamping process. When manually feeding materials, do not choose a punch with too many strokes; for automatic stamping, choose equipment with as many strokes as possible. When deep drawing, equipment with too many strokes cannot be used, because the drawing is too fast, the material will not be fully deformed in time, and the parts will be easy to crack.

The above is an introduction to the selection of punch presses. Users should choose according to their own working environment and equipment requirements during the purchase process to ensure the work efficiency in the production and processing work.