In previous articles, we have briefly introduced to youHardware Stamped Parts, There is a flange in the hardware stamping parts. Do you know what the purpose of this flange is? Why is it necessary to determine a reasonable flange value? What are the main factors affecting a reasonable flange value? When laying out hardware stampings, the material left between workpieces or between the workpiece and the edge of the strip is called a flange. Although the flange is scrap material, it plays a significant role in the process. The function of the flange is:

1) Keep the strip material with a certain stiffness to facilitate feeding.

2) Compensate for positioning errors. Even if there is a certain error, it will not ruin the workpiece. A reasonable blank margin width is the minimum width that ensures the quality of the cutting surface of the punched workpiece and improves the lifespan of the die. A blank margin that is too narrow will be torn during the punching process, causing elongated burrs on the metal stamping parts and affecting feeding.

There are many factors affecting the value of edge overlap, mainly the following points:

1) Material properties: The harder the material, the smaller the overlap value.

2) When punching thin materials, a larger overlap value should be used to maintain good rigidity, but for thick materials, a larger overlap value should also be applied to ensure the overlap does not tear. It has been proven that when the material thickness is 0.5–1 millimeter, the overlap value is relatively small.

3) The larger the work size and the more complex the shape, the greater the overlap value.

4) When using side pressure plates for feeding, to make the strip material stick to one side during feeding, a smaller overlap value can be used.

The principle of processing hardware stamping parts is the same as that of other stamping parts. If the flange of a hardware stamping part is torn during the punching process, it can make the punched part uneven, or even pull the flange into the punch die gap, causing severe wear or damage to the cutting edge. An excessively large flange not only reduces material utilization but also increases the stripping force of the die. It has been proven that with a reasonable flange value, the die life can be increased by more than 50%.