Method of improving die life and die grinding

Method of improving die life and die grinding

How to increase the service life of the mold

For users, increasing the service life of the mold can greatly reduce the stamping cost. The factors that affect the service life of the mold are as follows:

  • 1. Material type and thickness;
  • 2. Whether to choose a reasonable mold gap;
  • 3. The structure of the mold;
  • 4. Whether the material has good lubrication during stamping;
  • 5. Whether the mold has undergone special surface treatment;
  • 6. Such as titanium plating, titanium carbonitride;
  • 7. Align the upper and lower turrets;
  • 8. Reasonable use of adjusting shims;
  • 9. Whether the diagonal blade mold is used correctly;
  • 10. Whether the mold base of the machine tool is worn;

Mold polishing

1. The importance of grinding

The regular polishing of the die ensures consistent stamping quality. Regularly grinding the mold can not only increase the service life of the mold, but also the service life of the machine tool. The correct timing of sharpening must be mastered.

2. The specific characteristics of the mold need to be sharpened
For the sharpening of the mold, there is no strict hammering times to determine whether sharpening is required. This mainly depends on the sharpness of the blade. Mainly determined by the following three factors:

  • (1) Check the fillet of the cutting edge. If the fillet radius reaches R0.1mm (the maximum R value cannot exceed 0.25mm), sharpening is required.
  • (2) Check the stamping quality. Are there any glitches?
  • (3) Determine whether sharpening is required based on the noise of machine punching. If the same pair of dies have abnormal noise when punching, it means that the punch is blunt and needs to be sharpened.
    Note: The edge of the blade is round or the back of the blade is rough. Sharpening should also be considered.

3. Sharpening method

There are many ways to sharpen the mold, which can be achieved with a special sharpener or on a surface grinder. The sharpening frequency of punch and die is generally 4: 1. Please adjust the mold height after sharpening the knife.

  • (1) Harm of incorrect sharpening method: Incorrect sharpening will aggravate the rapid damage of the die blade, resulting in a greatly reduced number of hammers per sharpening
  • (2) The benefits of the correct sharpening method: regular sharpening of the mold can keep the punching quality and accuracy stable. The blade of the mold is damaged slowly and has a long service life.

4. Sharpening rules

The following factors should be considered when grinding the mold:

  • (1) In the case of R0.1-0.25 mm, the sharpness of the cutting edge fillet depends on the sharpness of the cutting edge.
  • (2) The surface of the grinding wheel should be cleaned.
  • (3) It is recommended to use soft and coarse-grained grinding wheels. Such as WA46KV
  • (4) The amount of grinding (cutting tool) should not exceed 0.013 mm. Excessive grinding will cause the mold surface to overheat, which is equivalent to annealing treatment. The mold becomes soft and greatly reduces the life of the mold.
  • (5) When grinding, sufficient coolant must be added.
  • (6) When grinding, the punch and the lower die should be firmly fixed, and special tooling fixtures should be used.
  • (7) The grinding amount of the mold is constant. If this value is reached, the punch will be scrapped. If you continue to use it, it is easy to damage the mold and machine.
  • (8) After grinding, the edges should be treated with a whetstone to remove excessively sharp edges.
  • (9) After sharpening, clean, demagnetize and oil.
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