Limit fit & Tolerance : Unilateral tolerance :variation is only one direction Bilateral tolerance : variation on both side Fundamental deviation: basic size Tolerance = upper limit - lower limit :Permissible limit of variation for manufacturing is assigned to parts for manufacturing purpose as boundary of acceptable build. Basic size : Nominal diameter of shaft or hole it is same for both Fit : it is clearance between two mating parts, it can be determined by whether the parts move, temporary joint ,permanent joint. Clearance fit : Hole is larger than shaft. Transition fit : Hole is fractionally smaller than shaft. Interference fit : Hole is smaller than shaft. Functional dimension : have to be machined and fit with other mating parts. Drilling : unilateral Dimension BIS (Bureau of International Standard) Grade of Tolerance :18 Fundamental tolerance : 25 BSI (British standard System) ...
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