Stamping is one of the practical processes for mass parts forming. In the process of stamping production, the problem of die is the most, which is the most important factor in the whole stamping production factor. It directly affects the production efficiency and cost. Affects the product delivery cycle. Die problems mainly focus on die damage, product quality defects and die grinding, which have long plagued industry production. Only by correctly handling these key points. Stamping production can proceed smoothly
1 Die Failure
Die failure is the most common problem in stamping production, which often causes shutdown and affects product production cycle. Therefore, it is necessary to find out the cause of die failure as soon as possible and maintain it reasonably.
Die damage refers to the cracking, breaking and opening of the die. In order to deal with the problem of die damage, it is necessary to find out the reasons from the design, manufacturing process and use of the die.
First of all, it is necessary to check whether the manufacturing material of the die is suitable and whether the corresponding burying process of hot spot is reasonable. Usually, the heat treatment process of die material has a great influence on it. If the quenching temperature of the die is too high, the quenching method and time are unreasonable, and the tempering times and temperature, elbow selection are not appropriate, the die will be damaged after entering the stamping production. The size or depth of blanking hole is not enough to block the groove hole and cause the damage of blanking plate. The spring force design is too small or the equal height sleeve is unequal, which will cause the spring to break and the blanking plate to tilt. It will cause overlapping punching and damage parts. If the punch is not fixed properly or the screw is not strong enough, it will cause the punch to fall off or break.
2. Quality Defects of Parts
The most common part quality defect is product size oversize. Only a few products have surface quality problems.
Dimension overshoot is a serious defect of stamping parts. In this regard, first of all, the design of the die should be checked and checked, and the reasons for the design and manufacture should be excluded. If the excess size is related to the thickness of the material, the thickness, material quality and hardness of the stamping material should be tested.
Over-tolerance in stamping process is mainly caused by wear of die, poor orientation and deformation of parts. The abrasion of the edge of the die will result in too large burr or bigger size of the cut profile, smaller punch hole, and flatness exceeding tolerance. The die should be sharpened or replaced. Mold Man Magazine Wechat Professional, worthy of attention! Poor orientation includes no orientation, no guide pin or other positioning device, no loosening of feeder, excessive distance due to wear of positioning block, incorrect length of guide plate or excessive gap between guides, etc. Deformation of parts in production mainly includes impact deformation, for example, the blow-out pressure of products is too strong or the impact of gravity falls too large deformation: when the material is discharged by extrusion or bracket deformation, the position of discharging material should be cleared in time or the space of discharging material should be enlarged: the improper deformation of ejection. For example, if the ejector pin is not properly prepared, the spring force is inappropriate or the ejector is too long, the elasticity should be adjusted or the position or number of pins should be changed; the blanking deformation should be achieved. Partial bending parts can not allow overlapping of materials, they must be dropped every time. Pressure cushion can be used to eliminate the dish strain; punching and shearing deformation, mainly the material distortion is uneven. Dimension enlargement or center asymmetry; floating chip extrusion deformation is caused by scrap floating or fine chip remaining on the die surface or foreign body extrusion deformation.
Surface quality is not up to standard
冲压制件的表面质量问题，主要是毛刺过大。造成制件毛刺过大的原因，首先是模具刃口的磨损，应重新研磨模具(下述)，确保刃口锋利。 3 模具的刃磨
The surface quality problems of stamping parts are mainly excessive burrs. The reason for the excessive burr is the wear of the die edge. The die should be re-grinded (as follows) to ensure that the edge is sharp. 3. Grinding of Dies
In stamping production, the die should be grinded reasonably. It can effectively improve the life of the die, save the cost of the die and greatly reduce the cost of the product.
When the cutting edge of the die is worn to a certain extent, the original sharp edge becomes blunt, which will cause the burr of the blanking part to be too large and the precision of size and shape and position to be reduced. Therefore, the die must be grinded to restore its sharp cutting edge. Reduce the punching burr and the deviation between size and shape, improve the surface quality of the formed parts. If the die is not grinded in time, the blunt edge will suffer severe friction of hard, large and thick burrs because of delaying the grinding time, resulting in excessive wear and tear of the vicious circle of the die, which will lead to several times of the grinding amount to restore the sharp edge and greatly shorten the life of the die. When the burr of the part is about to exceed the allowable burr height, the production should be stopped immediately and the die should be sharpened.