Control interchangeability of mating parts.
Limits are maximum and minimum allowed sizes; tolerance is their difference. Fits: clearance (running/sliding), transition and interference (press fit); ISO system uses letters for position (H hole, h shaft) and numbers for grade (IT6, IT7). Tighter tolerances cost more.
H7/h6 is a close sliding fit used for locating parts.
Tolerances define the acceptable variation in a part, which decides whether parts fit together and how much they cost to make.
Control interchangeability of mating parts.
Tolerances define the acceptable variation in a part, which decides whether parts fit together and how much they cost to make.
A fit that gives a range of clearance or interference from the tolerances of the hole and the shaft.
Tighter tolerances cost more in machining and inspection, so they should be applied only where the function needs them.
Typical applications include specifying a clearance of 0.05 mm between a pin and a hole, setting a tolerance on a bearing seat for a press fit and choosing a loose tolerance on a cosmetic cover that does not carry load.
Study "Measurement tools" first (topic 9 of 102 in Manufacturing, Robotics & Systems). It covers the groundwork this topic builds on.
Basic size and deviations. H7/g6, H7/p6. Allowance.
H7/h6 is a close sliding fit used for locating parts.
The next topic is "Geometric dimensioning and tolerancing", which builds directly on this one.
It is classed as Beginner in Manufacturing, Robotics & Systems (topic 10 of 102). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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