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The wiredrawing mold own processing qualitative factors causes the mold attrition 

(1) diamond mold semifinished product and the mold steel bushing crustification is asymmetrical, the agglutination hard alloy steel bushing distributes non-uniform or has the crevice, easy to cause to draw in the wire rod process to have the U shape fissure;

(2) diamond mold semifinished product in the laser drilling process, the agglutination trace cleaning up unclean or will be heated non-uniform will cause in the Jin'gang riddlings the metal catalyst, the cement and so on to gather a pile, such easy to cause in the drawing process the mold to present the pit;

(3) mold roll pass design is unreasonable, the entrance lubrication area opens the mouth, the stereotypia area to be excessively long too small, will cause the lubrication to be impeded, causes the mold to wear even disrupts.

In the drawing process does not use, when the factor causes the mold attrition

(1) wiredrawing area reduction rate is oversized, causes the mold to have the fissure or stave. The fissure or breaks the crack major part is the internal stress release produces. In any material structure, the existence internal stress is inevitably, draws when the wire rod produces the internal stress may strengthen the diamond micro-crystallic structure originally, but when the wiredrawing area reduction rate oversized, is unable to lubricate promptly, thus temperature rise Gao Jiuhui has caused the diamond mold to indicate that the partial materials move away, the micro-crystallic structure withstands the stress greatly increases, causes it easier to have the fissure or stave.

(2) wire rod's stretch spool thread and the nib middle line is asymmetrical, causes has the stress to the wire rod and the back guy mold to affect non-uniform, but the mechanical vibrations produce the impact also becomes the very high stress peak value to the wire rod and the back guy model, both will accelerate mold's attrition.

(3) the wire rod degree of hardness which non-uniform creates because of the annealing non-uniform and so on factors easy to cause the diamond wiredrawing mold premature to have the fatigue damage, forms the ring-like trench, the aggravating nib attrition.

(4) wire rod surface roughness, the superficial adherency oxide layer, the sandy soil or other impurities and so on will cause the mold excessively quickly attrition. When wire rod through nib, hard, the crisp oxide layer and other adherency impurity will look like the grinding compound to create the back guy mold nib very quick attrition and the abrasion wire rod surface equally.

(5) lubrication impeded or the lubricating oil includes the metal detritus impurity to cause the mold attrition. Lubricates impeded will cause when the wiredrawing the diamond nib surface temperature to elevate excessively quickly, the diamond crystal grain will fall off, causes the mold damage. When the lubricating oil is impure, when the metal detritus which especially includes draws when falls off, extremely easy to scratch the mold and the wire rod surface.