How are tolerances shown on an Engineering Drawing

How are tolerances shown on an Engineering Drawing?

What are tolerances?

Tolerances refer to the amount a dimension my vary from it’s maximum to its minimum value. Tolerances can be indicated as a unilateral tolerance or a bilateral tolerance.

Unilateral Tolerance

The Unilateral Tolerance (as shown) indicates the base dimension and how much the actual manufactured dimension may vary from this dimension.

As shown, the Internal Diameter (ID) may be, at a minimum 29,98 and the maximum of 30,02.

In the same way as the ID, the OD (Outer Diameter) has a minimum of 49,98 & a maximum of 50,02

Bilateral Tolerance

The Bilateral Tolerance also indicates a maximum and minimum value. As the example shows, the minimum dimension the shaft may be is 30,06 and the maximum is 30,09 is a participant in the Google advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to third parties. This site also participates in other affiliate programs and is compensated for referring traffic and business to these companies.