Stamped parts are parts with certain shape, size and performance obtained by stamping process. Stamping parts are widely used and gradually become an important part in the current parts manufacturing industry. Stamping process is affected by three factors: equipment type, workpiece material and oil performance. The following is a brief introduction by YMP Petrochemical to how to improve the quality of stamping parts:
I. Selection of Stamping Equipment
According to the nature of the stamping process to be completed, the size of the batch, the geometric size of the stamping parts (including thickness, whether to stretch, shape) and accuracy requirements to determine:
(1) Small and medium-sized cutting pieces and bending pieces shall adopt open mechanical punching machines.
(2) Medium-sized stamping parts adopt closed mechanical punching machines.
(3) Hydraulic press is adopted for small batch large-scale thick plate stamping parts.
(4) High-speed punching machine or automatic punching machine is selected for large quantities or complicated parts at the beginning.
Second, the choice of stamping materials
There are three main stamping processes: blanking, bending and stretching. Different processes have different requirements for plates. Material selection should also consider the selection of plates according to shape and process.
(1) Blanking requires that the plate should have sufficient deformation to ensure that the plate will not crack during blanking. Soft materials have good blanking performance, and after blanking, parts with smooth section and small inclination can be obtained. The quality of hard materials after blanking is not good and the cross section is uneven, especially for thick plates. For brittle materials, tearing is easy to occur after blanking, especially when the width is very small.
(2) The plate to be bent should have sufficient deformation and low yield limit. Plate with high deformation is not easy to crack when bending. Plate with lower yield limit and lower elastic modulus has small deformation after bending and is easy to obtain accurate bending shape. Materials with higher brittleness must have larger relative bending radius when bending, otherwise cracking will easily occur during bending.
(3) The stretching of the plate requires not only the minimum depth, simple shape and smooth transition as much as possible, but also a good amount of deformation of the material. Otherwise, it is very easy to cause distortion and deformation of the whole part, local wrinkling and even tensile cracking of the stretched part.
Stamping oil plays a key role in stamping process. Good cooling performance and extreme pressure anti-wear performance have made a qualitative leap in improving the service life of dies and workpiece precision. According to the different material of the workpiece, the emphasis of the stamping oil performance is different when it is selected.
(1) Silicon steel plate is a relatively easy punching material. Generally, low viscosity punching oil is selected on the premise of preventing punching burrs for workpiece cleaning.
(2) When selecting stamping oil for carbon steel plate, the better viscosity shall be determined according to the process difficulty, drawing oil feeding method and degreasing.
(3) Galvanized steel plates will have chemical reaction with chlorine additives. Therefore, when selecting stamping oil for galvanized steel plates, attention should be paid to the problem of white rust that may occur in chlorine type stamping oil. Using YMP sulfur type stamping oil can avoid the problem of rust, but degreasing should be done as soon as possible after stamping.
(4) Stainless steel plates are easily hardened materials, requiring the use of drawing oil with high oil film strength and sintering resistance. Generally, stamping oil containing sulfur and chlorine compound additives is used to ensure extreme pressure performance while avoiding problems such as burrs and cracks on workpieces.
These are the factors that affect the quality of stamping parts. With the rapid development of precision stamping technology, small stamping parts can meet the needs of various types of machine tools, electrical appliances, instruments and other manufacturing industries.
Source of this article:https://www.ymp.com.hk/