About the dimensional tolerance standard of metal stamping parts

The tolerance of precision metal stamping parts is related to the size and the selected tolerance level. The selection of the tolerance level should not only meet the design requirements, but also consider the possibility and economy of the process. In other words, when the requirements are met, try to increase To the tolerance value, that is, the lower tolerance level is selected. 'GB/T13914-2002 Dimensional Tolerance of Stamping Parts' specifies the dimensional tolerance of stamping parts. The dimensional tolerances are respectively specified for flat stamping parts and forming stamping parts. The dimensional tolerance value of stamping parts is related to the two dimensions of stamping part size and plate thickness, and on the other hand, it is related to accuracy grade. Dimensional tolerance of flat stamping parts: divided into 11 grades, indicated by ST1 to ST11, among which ST means dimensional tolerance of flat stamping parts, and the code of tolerance grade is indicated by Arabic numerals. From ST1 to ST11, the accuracy level decreases in order. Dimensional tolerance of forming stamping parts: forming stamping parts are divided into 10 accuracy grades, which are represented by FT1 to FT10, where FT represents the dimensional tolerance of forming stamping parts, and the Arabic numerals indicate the tolerance level. From FT1 to FT10, the accuracy grades decrease in order. The limit deviation of stamping parts: the hole size press deviation is 0, the upper deviation is the lower deviation plus the dimensional tolerance; the shaft size specifies that the upper deviation is the basic deviation, the value is 0, and the lower deviation is the upper deviation minus the dimensional tolerance. For hole center distance, hole edge distance, bending, drawing length, height, etc., the upper and lower deviations are specified as half of the dimensional tolerance. Tolerance is the range of dimensional changes. The higher the value, the lower the accuracy and the less difficult the processing; the smaller the value, the higher the accuracy and the greater the processing difficulty. Well, what are most of the items that should be paid attention to in production? 1. Bending angle: the angle size of the stamped part formed by bending 2. Punching angle: the angle size formed by punching at the plane of the flat plate or the formed part 3. Punching fillet radius: punching, Blanking and other separation processes to form the linear size of the fillet radius of the stamping part 4. Forming size: the linear size of the stamping part processed by bending, stretching and other processes 5. Punching size: punching, blanking and others Recommended article for the linear size of stamping parts processed by separate processes: Summarize several factors that affect the machinability of stamping materials