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How does Tianhui hardware teach you to know the cause of common failure of hardware mould and how to deal with it

2020-10-14

Causes and treatment of common failures in hardware molds

In progressive die stamping production, in view of the stamping adverse phenomenon must make a concrete analysis, to take effective countermeasures, fundamentally solve the problem of what happened, so can reduce the production cost, achieve production smoothly, the following is the production of common stamping unhealthy phenomenon as follows, the reasons and countermeasures analysis.

1. Hopping chip crushing 

(1) Cause: A. Large clearance; 

B. Improper feeding; 

C. Stamping oil drops are too fast and the oil is sticky; 

D. The mold is not demagnetized;

E. Punch wear, and the material is attached to the punch;

F. The punch is too short and the insert die length is insufficient;

G. The material is hard and the punching and cutting shape is simple;

H. Emergency measures.

2. Rough edges of pieces

(1) Cause: A. Knife edge wear;

B. The effect is not obvious after studying the cutting edge due to large gap;

C. Blade Angle collapse;

D. Unreasonable upper and lower deviation or looseness of clearance.

E. Upper and lower dislocation of mould.

(2) Countermeasures: 

A. Research and study of knife edge;

B. Control the machining accuracy of the convex and concave die or modify the design clearance;

C. Research and study knife edge;

D. Adjust the blanking clearance to confirm the abrasion of template holes or machining accuracy of molding parts;

E. Replace the guide or reassemble the module.

3. Deviation size variation of blanking

 (1) Causes: A. The cutting edge of convex and concave die is worn, resulting in burr (shape is larger, inner hole is smaller);

B. Poor machining accuracy of design size and clearance; 

C. Offset positioning of punch and die insert at blanking level, uneven clearance;

D. Wear of guide pin and insufficient pin diameter;

E. Guide wear;

F. Improper feeding distance, pressing and relaxation adjustment of the feeder;

G. Die closing height is improperly adjusted;

H. The stripper forging block is worn at the pressing level, with no pressing (strong pressure) function (material drawing and turning causes small punching);

I. Heavy pressure of unloading insert is too deep and punching is too large; 

J. Mechanical property variation of stamping materials (strength elongation is unstable); 

K. When punching, the punching force pulls on the material and causes size variation.

(2) Countermeasures: 

A. Research and study of knife edge; 

B. Modify the design and control the machining accuracy; 

C. Adjust its position accuracy and blanking clearance: 

D. Replace guide pin: 

E. replace guide post and guide sleeve; 

F. Readjust the feeder;

G. Adjust the height of the closed die;

H. Grind or replace stripper inserts to increase the pressure function and adjust the pressure.