Improper use of the drawing process factors leading to rapid wear of the mold.
(1) drawing surface shrinkage is too large, resulting in cracks or broken the mold. Cracks or broken crack mostly generated by the release of internal stress. In any material structure, the presence of internal stress is inevitable, the internal stress generated when pulling the wire could enhance the mold microcrystalline structure, but brushed surface shrinkage is too large, not been able to lubricate thus excessive temperature rise will lead to mold It indicates that part of the material is removed, microcrystalline structure to withstand stress is greatly increased, making it more prone to cracking or breaking.
(2) Tensile wire centerline axis of the die hole asymmetry, resulting in the wire and cable model for uneven stress, mechanical vibration and shock can also cause high stress peaks on the wire and cable model, both We will accelerate the wear of the mold.
(3) non-uniform due to uneven annealing wire hardness caused by other factors likely to cause diamond drawing die premature fatigue damage, the formation of the annular groove, increased die bore wear.
(4) the wire surface roughness, the surface oxide layer adhesion, sand or other impurities cause excessive wear of the mold. When the wire through the die orifice, hard, brittle oxide layer and other contaminants will adhere to the same manner as the abrasive Pull die bore quickly cause wear and abrasion wire surface.
(5) poor lubrication or oil-containing impurities cause mold wear metal debris. Poor lubrication makes drawing die hole surface temperature quickly, diamond grains fall off, leading to mold damage. When the lubricant unclean, especially when drawing containing metal debris shedding, very easy to scratch the surface of the die and wire.
Mold rapid wear of drawing dies often because of their own processing quality.
(1) drawing die blanks and die steel sleeve asymmetrical mosaic inlaid alloy steel jacket or uneven distribution of voids, are likely to result in a U-shaped crack in the wire drawing process;
(2) diamond die blanks in laser drilling process, the sintering is not clean or clean up traces of uneven heating may result in the diamond layer metal catalyst, combined together into a pile and the like, so easily lead to mold appears pits during drawing;
(3) Mold unreasonable pass design, lubrication inlet opening area is too small, setting zone is too long, it will cause poor lubrication, resulting in die wear or chipping. |
