1 Scope
This standard specifies the numerical tables and the calculation of values for standard tolerance and basic deviation of limit and fit. These values tabulated are to be taken as authoritative for the application of the system.
This standard applies to the sizes of cylindrical and non-cylindrical smooth workpieces.
2 Normative references
The following standards contain provisions which, through reference in this standard, constitute provisions of this standard. At the time of publication, all the editions listed are valid. All standards are subject to revision, and all parties using this standard are encouraged to investigate the possibility of applying the latest editions of the following standards.
GB/T 1800.1-1997 Limits and Fits — Bases — Part 1: Terminology
GB/T 1800.2-1998 Limits and Fits — Bases — Part 2: Basic rules of tolerances, deviations and fits
3 Standard tolerance for basic sizes to 3,150 mm
3.1 Standard tolerance
The formula and numerical rounding rules for the standard tolerance calculation are given in annex A(Normative).
3.2 Values of standard tolerance grades (IT)
Values of standard tolerance grades IT 1 to IT18 with basic sizes up to 3,150 mm inclusive are given in table 1.
Note: Values for standard tolerance grades IT 01 and IT 0 with basic sizes up to 500 mm are given in annex A.
Foreword i
ISO foreword iii
1 Scope
2 Normative references
3 Standard tolerance for basic sizes to 3,150 mm
4 Fundamental deviations for basic sizes up to 3,150 mm
Annex A (Normative) Calculation of standard tolerance and fundamental deviation
Annex B (Normative) Examples