Causes of hardware mold failures and solutions

In the stamping production of hardware molds, specific analysis must be done for the stamping defects, and effective countermeasures must be taken to fundamentally solve the problems that occur, so as to reduce production costs and achieve smooth production. The following is the analysis of the causes and treatment countermeasures of the common stamping defects in production as follows for the reference of mold maintenance personnel. 1. Punching parts burrs. (1) Reasons: a. The blade is worn; b. The effect is not obvious after the clearance is too large; c. The blade is chipped; d. The gap is unreasonable up and down or loose; e. The mold is misaligned up and down. (2) Countermeasures: a. Research the knife edge; b. Control the machining accuracy of the metal mold or modify the design gap; c. Research the knife edge; d. Adjust the blanking gap to confirm the wear of the template hole or the processing accuracy of the molded part; e. Replace the guide Pieces or re-molding. 2. Jumping chip crush (1) Reasons: a. The gap is too large; b. Improper feeding; c. The punching oil drops too fast and the oil is sticky; d. The mold is not demagnetized; e. The punch is worn and the crumb is pressed against the punch. Upper; f. The punch is too short, and the length of the insert is insufficient; g. The material is hard and the punching shape is simple; h. Emergency measures. (2) Countermeasures: a. Control the machining accuracy of the hardware mold or modify the design gap; b. Trim the material belt and clean the mold in time when it is sent to the appropriate position; c. Control the amount of stamping oil drops, or change the oil type to reduce the viscosity; d. After training, it must be demagnetized (more attention should be paid to the punching material); e. Research the punch edge; f. Adjust the length of the punch blade into the concave mold; g. Change the material and modify the design. The punch is inserted into the end face to push out or trim out the bevel or arc (pay attention to the direction). Reduce the bonding area between the end face of the punch edge and the chip; h. Reduce the sharpness of the die edge, reduce the amount of training on the die edge, and increase the surface roughness (coating) of the straight edge of the die. Use a vacuum cleaner to suck up the waste. Reduce the impulse speed and slow down the chipping. 3. Chip blockage (1) Reasons: a. The leakage hole is too small; b. The leakage hole is too large, and the chip rolls; c. The knife edge is worn and the burr is large; d. The punching oil drops too fast and the oil is sticky; e. The surface of the straight edge of the die is rough, and the powder sintering adheres to the edge; f. The material is soft; g. Emergency measures. (2) Countermeasures: a. Modify the leaking hole; b. Modify the leaking hole; c. Sharpen the knife edge; d. Control the amount of dripping oil and change the oil type; e. Surface treatment, polishing, and pay attention to reducing the surface roughness during processing ; Change the material, f, modify the blanking gap; g, trim the slope or arc on the end of the punch blade (pay attention to the direction), use a vacuum cleaner, and add air to the blanking hole of the backing plate. 4. Variation in the size of the blanking deviation (1) Reasons: a. The cutting edge of the hardware mold is worn, resulting in burrs (the shape is too large, the inner hole is too small); b. The design size and clearance are improper, and the processing accuracy is poor; c. The blanking position is convex Mold and die inserts are offset, and the gap is uneven; d. The guide pin is worn and the pin diameter is insufficient; e. The guide is worn; f. The feeding distance, pressing and loosening of the feeder are improperly adjusted; g. The mold is closed Improper height adjustment; h. The pressure position of the unloading insert is worn, and there is no pressing (strong pressure) function (the material pulling and turning causes the punching to be small); i. The unloading insert is too strong and the punching is too large; j. Variations in the mechanical properties of stamping materials (unstable strength elongation); k. When punching, the punching force pulls the material and causes dimensional variation. (2) Countermeasures: a. Research and repair the knife edge; b. Modify the design to control the machining accuracy; c. Adjust its position accuracy and blanking gap; d. Replace the guide pin; e. Replace the guide pin and guide sleeve; f. Re-adjust Feeder; g. Re-adjust the height of the closed mold; h. Grind or replace the unloading insert, increase the pressure function and adjust the pressure; i. Reduce the depth of the pressure; j. Change the material to control the quality of the feed; k. Punch The end face of the blade is trimmed with a slope or arc (pay attention to the direction) to improve the stress condition during punching. When permitted, the unloading part is located on the unloading block with a guide function. 5. Material jam (1) Reasons: a. Improper adjustment of the feeding distance, pressing and loosening of the feeder; b. Variation in the feeding distance during production; c. Feeder failure; d. The material is curved, the width is out of tolerance, and the burrs are large; e. Die stamping is abnormal, caused by sickle bend; f. Insufficient aperture of guide material, upper die pulls the material; g. Bending or tearing position is not smooth up and down; h. The stripping function of the guide plate is set improperly, and the material is taped. Upper belt; i. The material is thin and warps during feeding; j. The mold is improperly erected, and the deviation from the verticality of the feeder is large. (2) Countermeasures: a. Re-adjustment; b. Re-adjustment; c. Adjustment and maintenance; d. Replace material to control the quality of feed; e. Eliminate the sickle bend of the material belt; f. ; G. Adjust the force of the stripping spring, etc.; h. Modify the guide plate to prevent the material from being taped; i. Add up and down pressure between the feeder and the mold, and add up and down extrusion safety switches; j. Re-erect the mold.