Causes of Damage to Wire Drawing Die
The rapid wear of the die is often due to the processing quality of the drawing die itself.
(1) Asymmetrical inlay of the wire drawing die blank and die steel sleeve, uneven distribution or gaps in the embedded carbide steel sleeve, all easily lead to U-shaped cracks during the wire drawing process;
(2) During the laser drilling process of the diamond die blank, the sintering traces are not cleaned or unevenly heated, which will cause the metal catalysts and bonding agents in the diamond layer to gather together, which will easily lead to pits in the mold during the wire drawing process;
(3) The mold hole design is unreasonable, the inlet lubrication zone opening is too small, and the setting zone is too long, which will lead to poor lubrication, resulting in mold wear and even chipping.
Improper use of factors in the drawing process causes rapid wear of the mold.
(1) The drawing surface shrinkage is too large, causing cracks or breakage in the mold. Most of the cracks or broken cracks are caused by the release of internal stress. In any material structure, the existence of internal stress is inevitable. The internal stress generated when drawing the wire can enhance the microcrystalline structure of the mold, but when the drawing surface shrinkage is too large, it cannot be lubricated in time and the temperature rise is too high, which will cause the mold. It shows that when part of the material is removed, the stress on the microcrystalline structure is greatly increased, making it more prone to cracks or breakage.
(2) The drawing axis of the wire is asymmetrical with the centerline of the die hole, resulting in uneven stress on the wire and drawing die, and the impact generated by mechanical vibration will also cause high-stress peaks on the wire and drawing die, both Will accelerate the wear of the mold.
(3) Factors such as uneven wire hardness caused by uneven annealing can easily cause premature fatigue damage to the diamond wire drawing die, forming annular grooves, and aggravating die hole wear.
(4) The surface of the wire is rough, and the surface adhesion of the oxide layer, sand, or other impurities will cause the mold to wear out too quickly. When the wire passes through the die hole, the hard and brittle oxide layer and other adhering impurities will cause the wire drawing die hole to wear quickly and scratch the wire surface like abrasives.
(5) Poor lubrication or lubricating oil contains metal chips and impurities that cause mold wear. Poor lubrication will cause the surface temperature of the die hole to rise too fast during wire drawing, and the diamond grains will fall off, causing damage to the die. When the lubricating oil is not clean, especially when it contains metal chips that fall off during drawing, it is very easy to scratch the surface of the mold and the wire.