If the size of hole is 100±0.15, then the tolerance is:

Concept: 

Tolerance:

• It is the difference between the maximum limit of size and the minimum limit of size.
• It is always positive and is expressed only as a number without a sign.
• So, the tolerance of a hole is the difference between the maximum diameter of the hole and the minimum diameter of the hole.
• Similarly, the tolerance of a shaft is the difference between the maximum diameter of the shaft and the minimum diameter of the shaft.

Basic size:

• It is the size based on which the dimensional deviations are given.

Actual size:

• It is the size of the component by actual measurement after it is manufactured.
• It should lie between the two limits of size if the component is to be accepted.

Limits of size:

• These are the extremely permissible sizes within which the operator is expected to make the component.

Maximum limit of size:

• It is the greater of the two limit sizes.

Minimum limit of size:

• It is the smaller of the two limits of size.

Calculation:

Given:

size of the hole is 100±0.15

Maximum limit of size = 100 + 0.15 = 100.15 mm

Minimum limit of size = 100 - 0.15 = 99.85 mm

∵ Tolerance = (Maximum limit of size) - (Minimum limit of size)

⇒ Tolerance = 100.15 - 99.85 = 0.30 mm