GB/T 6092-2021Squares (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" Drafting.

This document replaces GB/T 6092-2004 "Right Angle Ruler". Compared with GB/T 6092-2004, except for structural adjustments and editorial changes In addition, the main technical changes are as follows.

a) Deleted the parameters of the square ruler with a measuring length of 40mm (see Table 10~Table 12 in the 2004 edition);

b) The flatness tolerance and straightness tolerance requirements of the base surface have been increased (see 5.4.2, 5.4.3);

c) Deleted the parallelism tolerance requirements of the two base surfaces (5.4.2 of the 2004 edition);

d) Modified the rigidity requirements of the flat square (see 5.5.1, 5.5.1 of the 2004 edition);

e) Added inspection conditions (see Chapter 6);

f) Modified the inspection method of geometric tolerances (see Chapter 7, Chapter 6 of the 2004 edition);

g) Deleted the parallelism tolerance value of the two base planes on the short side (2004 version of Appendix A.1);

h) Added reference data for physical properties of rock materials (see Appendix A);

i) The calculation formulas for the flatness tolerance value and straightness tolerance value of the base surface have been added (see Table B.1).

1 Scope

This document specifies cylindrical squares, rectangular squares, knife-edge rectangular squares, triangle squares, knife-edge-shaped squares, and wide-seat knife-edges.

The terms and definitions, styles and basics of square squares, flat squares, flat squares with seat, and wide-seat squares (collectively referred to as "squares") Parameters, requirements, inspection conditions, inspection methods, markings and packaging, etc.

This document is applicable to square rulers whose measuring surface length is 50mm~1600mm.

2 Normative references

The contents of the following documents constitute the indispensable clauses of this document through normative references in the text. Among them, dated quotations Only the version corresponding to that date is applicable to this document; for undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 17164-2008 Product terminology for geometric quantity measuring instruments

3 Terms and definitions

The following terms and definitions defined in GB/T 17164-2008 apply to this document.

4 Type, basic parameters and accuracy grade