What to do if burrs appear on metal stamping parts? How to avoid them?

Metal stamping parts are widely used in various fields such as automobiles, electronics, electrical appliances, and machinery. However, in actual production, burrs have always been a key focus of quality control. Burrs not only affect the appearance of parts but also cause assembly difficulties, affect functionality, and even pose safety hazards.

1. Common causes of burrs on metal stamping parts
(1) Inappropriate die clearance
During stamping, a scientific clearance must be maintained between the punch and the die. If the clearance is too large, it will cause tearing fracture of the material, thus forming large burrs; if the clearance is too small, it will easily lead to accelerated die wear, chipping, and also produce burrs.

(2) Severe wear of die cutting edges
After long-term use, the die cutting edges gradually become dull and cannot cut the material smoothly, which easily leads to tearing and burrs. Especially for hard materials such as high-strength steel and stainless steel, die wear is more likely to accelerate.

(3) Material Hardness Exceeding Range
Excessive material hardness or unstable material quality can lead to uneven cutting edges and a significant increase in burrs.

(4) Insufficient Stamping Lubrication
Insufficient lubrication increases friction, causing the material to be pulled during cutting, thus forming burrs.

(5) Insufficient Equipment Precision or Unstable Pressure
Insufficient parallelism and stability of the stamping press can also lead to uneven cutting surfaces and burr problems.

2. Solutions for Burrs on Metal Stamping Parts
(1) Deburring Processes
Common methods include:
Grinding: Roller grinding, centrifugal grinding, etc., suitable for small batch processing.
Polishing: Suitable for products with high appearance requirements.
Sandpaper/Abrasive Wheel Grinding: Suitable for local processing or sample finishing.
Laser Deburring: High efficiency, suitable for precision parts.
Electrolytic Deburring: Used for fine deburring of stainless steel and difficult-to-machine metals.
These methods can effectively improve the surface quality of parts and make the edges smooth.

(2) Recalibrating or Replacing the Die Edge
If the burrs originate from die wear, the die edge should be recalibrated or replaced in time to ensure cutting sharpness.

(3) Adjusting the Die Clearance
Adjust the clearance between the punch and the die to a reasonable range according to the material thickness. For example, the clearance is generally about 5%–10% of the material thickness; different materials require appropriate adjustments.

(4) Improve lubrication conditions
Adding appropriate stamping oil can reduce friction and decrease tearing burrs.

(5) Check equipment performance. Maintain the press to ensure stable slide accuracy and downward pressure. If the equipment is aging, consider overhauling or upgrading.

3. How to avoid burrs at the source? What are the preventive measures?
(1) Design a reasonable mold structure
The following should be considered during the mold design stage:
Reasonable cutting edge angle
Appropriate closing height
Good guiding accuracy
These can significantly reduce the probability of burrs.

(2) Select suitable materials and suppliers
High-quality materials can reduce uneven fracture, thereby reducing burrs; at the same time, maintain the consistency of material hardness and batch.

(3) Establish a strict mold maintenance system
Regularly sharpening the cutting edge, checking the clearance, and keeping it clean are key steps to reduce burrs.

(4) Use higher precision stamping equipment
Modern high-precision presses have stable downward pressure and good repeatability, which can significantly reduce burrs.

(5) Strengthen process parameter control
Including: punching speed, punching pressure, and feeding accuracy. The more stable the process parameters, the lower the burr rate.

(6) Ensure adequate lubrication and select appropriate stamping oil
Good lubrication can improve cutting quality and reduce burr height.