Maintenance of progressive die and elimination of common faults 2

Check the accuracy of the guides. If the guide pins are worn out, the correct accuracy and function of the tape guides must be lost and they must be replaced. Check the condition of the spring (discharging spring, top material spring, etc.), depending on whether it is broken, or if it is not fractured after prolonged use, but fatigue has lost its original strength, regular maintenance and replacement must be done, otherwise the mold will be damaged. Or production is not smooth.
1.4 Adjustment of Die Clearance
The core positioning holes are worn out due to frequent and multiple combinations of the cores, resulting in large gaps after assembly (loose after assembly) or uneven gaps (positional deviations), all resulting in poor shape of the cross-section after punching. , The punch is easy to break, resulting in burrs, etc. It is possible to make proper clearance adjustment by checking the condition of the punched section.
When the gap is small, the section is small. When the gap is large, the section is large and the rough edges are large. A reasonable clearance is obtained by means of shifting. After the adjustment is made, appropriate records shall be made, and markings may also be made at the hole position for follow-up purposes. Maintenance operations. Daily production should pay attention to the collection and preservation of the original material when the mold better conditions, such as the follow-up production is not smooth or mold variation, can be used as a reference for mold maintenance. In addition, whether the auxiliary system such as the top material pin is worn or not, whether the material can be topped, and whether the guide pin and the bushing are worn, should be checked and maintained.
 2 Die common fault removal 2.1 burrs on the punching surface
Edge wear or chipping should be reground. The amount of cutting edge grinding should be based on the new cutting edge (the wear part has been completely removed). Due to the different processing methods used for forming parts, the service life of the molded parts is also different. Care must be taken when grinding, and the convenience of adding spacers should be taken into consideration.
Each time the edge of the grinding should be for all the convex, concave die edge, otherwise it will cause frequent maintenance and edge grinding, anti-production is not smooth. The gap between the molds is unreasonable. Even if the edge is re-polished, the effect is not good, and burrs occur soon. The shape of the punched cut surface must be inspected to confirm proper mold clearance adjustment. For some of the clearance of the clearance or small protrusions to make appropriate amplification.  2.2 Diverting debris
The gap between the molds is large. After grinding the edge of the die, the chipping phenomenon will increase. It is necessary to improve the machining accuracy of the core or modify the gap of the mold design. As the speed of punching increases, the problem of chip-removal is even more serious. Consider lowering the speed or using a vacuum cleaner. To improve the shape of the punch, trim the punch edge of the punch into a shape that is less likely to swarf, such as increasing the slope of the punch face or changing the direction of the pitch.
After the punch wears, the shavings adhere to the punch and cause swarf. The punch edge must be ground. The punch is short, producing swarf and lengthening it, which increases the punch length into the die. In addition, the impact of the material (hard, brittle), stamping oil sticky or oil droplets too fast adhesion effect, stamping vibration generated material divergence, vacuum adsorption and mold core not fully degaussing, etc. can cause debris to rise. The above factors should be dealt with accordingly.
2.3 Waste Blocking
Leakage hole size is small, especially small protruding parts can be properly enlarged. Swarf tumbling, that is, when the leakage hole is large, it causes the material tumbling to become clogged, the size of the leakage hole needs to be reduced or vacuum cleaner is used, the material surface is dripping with too much oil, the viscosity of the oil is too high, and the quantity of oil can be controlled or replaced Type of oil (reduced viscosity). Edge wear, waste burrs hug each other, squeezing occurs when blanking occurs, it is possible to burst the die, and it is necessary to grind the cutting edge in time.
If the surface of the die edge is poor, such as when the surface is rough or the die is overheated, the dust will sinter on the surface of the straight edge and the frictional resistance will increase when the scrap is removed. The surface of the straight edge of the die must be disposed. The shape of the punch and the inclination of the cutting edge of the punch die are not conducive to chip removal and make corresponding improvements. Sticky and soft materials can also cause difficulty in chip removal. (to be continued)