The Common Damages Happened in Drawing Process
The tungsten carbide drawing dies would loose function due to the reasons such as verdict-crack, horizontal-crack,off-core,deviation of size, and wear. The analysis as following:
1) Verdict-crack, it is caused since the outer-diameter of core unprocessed ,inner-hole of sleeve is processed badly presenting as taper-hole or trapezoid-hole, core-inlaying uncorrectly,geometry angle unreasonable ,excessive compression, defective of the tungsten carbide or wrong-selection of the grade and material tensile strength is not enough .
2) Horizontal-crack ,it is caused since the outer-diameter of core unprocessed ,inner-hole of sleeve is processed badly presenting as taper-hole or trapezoid-hole, core-inlaying incorrectly, defective of the tungsten carbide or wrong-selection of the grade and material tensile strength is not enough .
3) Deviation of size: it is caused due to bad wear-resistance of tungsten carbide, and without good lubricating in process.
4) Off-core: it is happened owing to incorrectly core-inlaying ,and bad sleeve materials
In a word, the mentioned problems happened owing to the tungsten carbide materials problem(quality defective ,and grade selection),mould processing and manufacturing problem and sleeve materials problem .At present ,the key point to optimize the solid performance of tungsten carbide is to improve tungsten carbide quality including reasonable selection of grade ,material design so as to achieve harmonization of high wear-resistance and tensile strength. meanwhile ,with help of reasonable hole-design including lubricating area, working area, size-forming area, exit area and size-design so as to get high comprehensive performance of tungsten carbide drawing dies .
