The thickness of the plate is 1.2 and one bend is deducted by 2mm. The thickness of the plate is 1.5 and the bend is deducted by 2.36mm. The thickness of the plate is 2.0 and the bend is deducted by 3.35mm. The external forming dimensions are all added up, and the number of bends (90 degrees) is reduced by the number of multiples of the coefficient. When the accuracy requirements are high, this coefficient must be actually calculated, because most of the plates are now inferior, and the lower die V of different bending machines The size of the opening is also different. The method to find the coefficient is to find a piece of 200-wide sheet of each thickness, fold 10 bends on it, measure the size of each bend, add up all the dimensions, and divide the difference from 200mm by 10 is the factor for a bend.
Every time it is folded, it is a few millimeters larger than the actual size. It is correct to measure the distance between the back gauge and the mold with a ruler. Reason analysis: Sheet bending is actually a stretching process, and the outer wall of the sheet is bent after bending. In fact, it is lengthened, so that the bending factor appears. For example, the bending deduction of 0.8mm thick iron plate is 1.5, such as a cold-rolled plate with a unfolded length of 100mm, 0.8mm thick, bending 20, and another bending is actually 81.5. The bending deduction is tried out, and the bending coefficient varies according to the upper die and the lower die of the bending machine. Fixed-length method; first measure the bottom die notch center to the front dimension minus half of the coefficient, this is the zero dimension. Use this zero size plus the size you want to bend, and the back ruler is set. The method of testing the bending coefficient, first cut a piece of material with a specified thickness, 100mm wide, and bend 40,. Measure two bends with a caliper, add the dimensions of the two bends together and subtract 100mm, which is the bending deduction for this kind of sheet. In addition, pay attention to the thickness of the material to be folded and the bottom groove must be clear.
