https://roymech.co/Useful_Tables/ISO_Tolerances/ISO_LIMITS.htm
Relevant Standards
BS EN 20286-1:1993(ISO 286-1:1988 )… ISO system of limits and fits. Bases of tolerances, deviations and fits
BS EN 20286-2 : 1993(ISO 286-2:1988 )… ISO system of limits and fits. Tables of standard tolerance grades and limit deviations for holes and shafts
Notes
The tolerance of size is normally defined as the difference between the upper and lower dimensions.
The need for tolerances to be identified on drawings is vital to allow assembly of parts in the desired way and interchangeability of parts as required in modern manufacturing methods.
ISO 286 implements 20 grades of accuracy to satisfy the requirements of different industries.
- IT01, IT0, IT1, IT2, IT3, IT4, IT5, IT6… Production of gauges and instruments.
- IT 5, IT6, IT7, IT8, IT9, IT10, IT11, IT12…Precision and general Industry.
- IT11, IT14, IT15, IT16…Semi finished products
- IT16, IT17, IT18 …Structural Engineering
Hole and Shaft tolerance tables- Using Fundamental Deviations and Tolerance Band T
ISO Tolerance Band T
(3-315mm size) ISO Shaft limit nearest Zero
(3-500mm shaft size) ISO Hole Nearest limit nearest Zero
(0-500mm hole size)
ISO Tolerance Band T
(315-3150mm size) ISO Shaft limit nearest Zero
(500-3150mm shaft size) ISO Hole Nearest limit nearest Zero
(500-3150mm hole size)
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