Illustration Method of Geometric Tolerances
Excerpt from JIS b0021 (1998)
■ Types of geometric tolerances and their symbols
Types of tolerance | Characteristic symbol | Definition of tolerance zone | Illustration and interpretation |
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Shape tolerance | Straightness tolerance | |||
Flatness tolerance | ||||
Roundness tolerance | ||||
Cylindrical tolerance | ||||
Line Contour Tolerance: Line contour tolerance not related to datum (ISO 1660) | ||||
Surface Contour Tolerance: Surface contour tolerance not related to datum (ISO 1660) | ||||
Types of tolerance | Characteristic symbol | Definition of tolerance zone | Illustration and interpretation |
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Attitude tolerance | Parallelism tolerance | 1. Parallelism tolerance of lines related to Datum straight line |
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2. Parallelism tolerance of the line associated with the datum plane |
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Square tolerance | 1. Right angle tolerance of line related to datum axis line |
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2. Linear angle tolerance of the line relative to the datum plane |
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Slope tolerance | 1. Linear slope tolerance relative to datum plane |
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2. Slope tolerance of the plane relative to datum plane |
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Types of tolerance | Characteristic symbol | Definition of tolerance zone | Illustration and interpretation |
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Position tolerance | Position angle tolerance | 1. Line position angle tolerance |
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Concentricity tolerance and coaxiality tolerance | ||||
Symmetry tolerance (Symmetry tolerance of center plane) | ||||
Runout tolerance | Circumferential deflection tolerance | 1. Circumferential runout tolerance - radial direction |
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2. Circumferential runout tolerance - axis direction |
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Full runout tolerance: Total runout tolerance in the circumferential direction | ||||
The lines used in the definition column of the tolerance zone represent the following meanings. Thick solid line or broken line: Form Thick dash-dotted line: Datum Thin solid line or broken line: Tolerance area Thin dotted line: center line Thin two-dot chain line: Supplementary projection plane or section Thick, two-dot chain line: projection of feature on supplemental projection plane or section |