Maintenance Tips for Progressive Dies and Troubleshooting of Common Faults 3

2.4 cards
Severe card material will cause mold damage, fracture, and chipping, which will make the mold work out of balance and seriously impair the accuracy. Feeding method, feeding distance and material relaxation position are not adjusted properly, and accurate adjustments must be made again.
During the production process, the feeding distance fluctuates and must be readjusted. The width of the material is poor or the material arc and burr are too large. Replace the material. Improper installation of the mold, deviation from the verticality of the feeding mechanism, reinstall the mold.
The distance between the die and the feeding mechanism is long, the material is thin, the material warps in the feeding, the feeding distance is inaccurate, the upper and lower pressing plates can be added in the neutral position, or the extruding material safety detection switch is added to the upper and lower parts of the material to make the feeding When abnormal, the stamping can be stopped in time.
The top of the mold is not well discharged. Check the material at the bending place of the die, check if the top is not stretched, the top is too long, and the top block (pin) is not handled well. Observe carefully and take corresponding measures.
 2.5 punch fracture
Scraping caused by various factors (excessive foreign matter in the mold), jamming of the waste, and jamming all cause the punch to break. In addition, when the feeding is started (half-shot), when the mold guide is inaccurate and the guide portion of the discharge insert is worn out, regular maintenance is required. When the material selected for the molding is not appropriate, the structural design of the small punch is improved, and the size is increased, and the added portion is removed at the punching edge.
Large and small punches are close to each other. Due to the traction of the material, the punch breaks, the guide protection must be strengthened, or the size of the punches must be increased. The small punches should be short by one material thickness. Pressing gap is too small, need to increase. Improper use of stamping oil (strong volatility) or no stamping oil for stamping, leading to increased edge wear or punch chipping, fracture, etc., need to change the type of oil and control the amount of oil drip oil.
2.6 Deformation of machined parts
Edge wear, so that the size of the blank material changes. If the burr is too large, subsequent bends may fluctuate and need to be ground or replaced. Feeding and guiding materials are inaccurate, the material belt is not released in time, or the pilot pin diameter is insufficient (wear) can not be accurately guided, need to re-adjust the feeding length and relaxation time, or replace the guide pin. The mold is not positioned accurately, with poor accuracy or wear, resulting in dimensional changes in the stamped part that must be reground or replaced.
The slippage of the material, resulting in dimensional changes during bending or punching (turnover, eccentricity, asymmetrical shape, etc.), must be adjusted to the pressure material, and the burrs on the front section should not be large, otherwise it would be detrimental to the subsequent forming. Pressure drop and wear occur in the contact between the discharge plate and the material, bending of the core, etc., resulting in changes in the molding dimensions and defects in the shape. The core must be reground or replaced.
Variations in material mechanical properties, width and thickness dimension errors, and changes in the dimensions of formed parts require proper control of the feed conditions. If more gaskets are added to the bending area, the bending dimension may become unstable and the entire pad may be used instead. In addition, the mold allowance hole is too small, the top of the poor, etc. will all lead to the formation of processing variations, depending on the specific situation to overcome.
2.7 Improper mold maintenance
This change without change, the screw is not tightened, the assembly is wrong or not restored as it will lead to more serious die damage, must pay attention. 
In short, for the failure of the progressive die in the stamping production, it needs to be analyzed, and the places that are often overlooked in the die repair, such as the guiding accuracy of the die, the accuracy of the guiding material, and the use condition of the spring in the die, will affect the rest of the die. Every part must be checked and maintained regularly. Accumulate and formulate reasonable mold maintenance data in production, that is, implement regular maintenance and eliminate the mold accidents in the bud, so as to extend the life of the mold and reduce the production cost. (Finish)