Tolerances

Tolerances and fits.

This book includes tables and calculations for easy option of fits of machine parts and determination of their dimensional tolerances and deviations. Using this tool the following tasks can be solved:

1. Selection of suitable fits of machine parts according to the international standard ISO 286.

2. Determination of dimensional tolerances and deviations of machine parts according to the international standard ISO 286.

3. Selection of preferred fits of machine parts and determination of their dimensional tolerances and deviations according to ANSI B4.1.

4. Determination of non-prescribed limit deviations of linear and angular dimensions according to ISO 2768.

5. Automatic design of a fit for the given clearance or fit interference respectively.

The data, procedures, algorithms and specialized literature and standards ANSI, ISO, DIN and others were used in the calculations.

List of standards: ANSI B4.1, ANSI B4.2, ISO 286, ISO 1829, ISO 2768, EN 20286, JIS B 0401

Control, structure and syntax of calculations.

Information on the syntax and control of the calculation can be found in the document "Control, structure and syntax of calculations".

Basic terms.

It is necessary that the dimensions, shape and mutual position of surfaces of individual parts of mechanical engineering products are kept within a certain accuracy to achieve their correct and reliable functioning. Routine production processes do not allow maintenance (or measurement) of the given geometrical properties with absolute accuracy. Actual surfaces of the produced parts therefore differ from ideal surfaces prescribed in drawings. Deviations of actual surfaces are divided into four groups to enable assessment, prescription and checking of the permitted inaccuracy during production:

• Dimensional deviations

• Shape deviations

• Position deviations

• Surface roughness deviations

This toll includes the first group and can therefore be used to determine...