This standard specifies the grades, codes and values of tolerances and the deviation values of dimensions for metal stamping parts.
This standard is applicable to the blanking and stamping parts of sheet metal.
2 Terms and Definitions
For the purposes of this document, the following terms and definitions apply.
2.1
blanking parts
stampings machined through flat blanking process
2.2
stamping parts
stampings machined by bending, deep drawing and other forming methods
3 Grades, Codes and Values of Tolerances of Dimensions for Stamping Parts
3.1 Tolerances of dimensions for blanking parts are classified into 11 grades, namely, ST 1~ST 11. ST represents the tolerance of dimensions for blanking parts; the codes for tolerance grades are represented with Arabic numerals. The tolerance grades are in descending order from ST 1 to ST 11. Tolerances of dimensions for blanking parts are applicable to dimensions of blanking parts and those machined from of stamping parts through blanking process. The values of tolerances of dimensions for blanking parts shall be in accordance with those specified in Table 1. See Figure 1 for examples of selection of basic dimensions B, D and L.
