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All Around Symbol Indicang that a tolerance applies to surfaces all around the part.
All Over Specificaon [ASME Y14.5-2009 Secon 8.3.1.6] In addion to a general profile of a surface tolerance there is the opon of specifying that the tolerance applies all over on the field of the drawing. It is important to realize that this specificaon, whether in a general note or on the field of the drawing, applies UNLESS OTHERWISE SPECIFIED.
All Around This Side of Parng Line [ ASME Y14.5-2009 Secon 3.14.1] To apply a requirement to all features all around one side of a parng line, the graphical symbol for all around this side of parng line is indicated on the leader line.
All Over This Side of Parng Line [ ASME Y14.5-2009 Secon 3.14.2] To apply a requirement to all features all over one side of a parng line, the graphical symbol for all over this side of parng line is indicated on the leader line.
Angularity Is the condion of a surface, axis, or centerplane, which is at a specified angle from a datum plane or axis.
Arc Length Indicang that a dimension is an arc length measured on a curved outline. The symbol is placed above the dimension.
Basic Dimension Used to describe the exact size, profile, orientaon or locaon of a feature. A basic di- mension is always associated with a feature control frame or datum target. (Theorecally exact dimension in ISO)
Between To indicate that a profile tolerance applies to several conguous features, le1ers may designate where the profile tolerance begins and ends. These le1ers are referenced using the between symbol (since 1994) or the word between on drawings made to earli- er versions of the Standard.
Concentricity Describes a condion in which two or more features , in any combinaon, have a com- mon axis.
Conical Taper Is used to indicate taper for conical tapers. This symbol is always shown with the vercal leg to the le5.
Connuous Feature [ASME Y14.5-2009 Secon 2.7.5] The note CONTINUOUS FEATURE or the connuous feature symbol is used to idenfy a group of two or more features of size where there is a requirement that they be treated geometrically as a single feature of size. Although the definion only menons features of size, there is an example of CF being applied to a pair of planar features.
Controlled Radius Creates a tolerance zone defined by two arcs (the minimum and maximum radii) that are tangent to the adjacent surfaces. Where a controlled radius is specified, the part contour within the crescent-shaped tolerance zone must be a fair curve without flats or reversals. Addionally, radii taken at all points on the part contour shall neither be
Counterbore/Spo6ace Is used to indicate a counterbore or a spo9ace. The symbol precedes the dimension of the counterbore or spo9ace, with no space.
Countersink Is used to indicate a countersink. The symbol precedes the dimensions of the counter- sink with no space.
Cylindricity Describes a condion of a surface of revoluon in which all points of a surface are equi- distant from a common axis..
Datum Feature Is the actual component feature used to establish a datum
Datum Target Is a specified point, line, or area on a part that is used to establish the Datum Reference Plane for manufacturing and inspecon operaons.
Depth/Deep Is used to indicate that a dimension applies to the depth of a feature. This symbol pre- cedes the depth value with no space in between.
Number of Places The X is used along with a value to indicate the number of mes a dimension or feature is repeated on the drawing.
Parallelism Is the condion of a surface, line, or axis, which is equidistant at all points from a datum plane or axis.
Parng Lines [ASME Y14.5-2009 Secon 3.14] Are depicted on casng/forging/molded part drawings as a phantom line extending beyond the part in applicable views, with the parng line symbol added.
Perpendicularity Is the condion of a surface, axis, or line, which is 90 deg. From a datum plane or a da- tum axis.
Posion Tolerance Defines a zone within which the axis or center plane of a feature is permi1ed to vary from true (theorecally exact) posion.
Profile of a Line Is the condion permi?ng a uniform amount of profile variaon, ether unilaterally or bilaterally, along a line element of a feature.
Profile of a Surface Is the condion permi?ng a uniform amount of profile variaon, ether unilaterally or bilaterally, on a surface.
Projected Tolerance Zone Applies to a hole in which a pin, stud, screw, etc., is to be inserted. It controls the per- pendicularity of the hole to the extent of the projecon from the hole and as it relates to the mang part clearance. The projected tolerance zone extends above the surface of the part to the funconal length of the pin, stud, and screw relave to its assembly
Radius Creates a zone defined by two arcs (the minimum and maximum radii). The part surface must lie within this zone.
Reference Dimension A dimension usually without tolerance, used for informaon purposes only. It does not govern producon or inspecon operaons. (Auxiliary dimension in ISO)
Regardless Of Feature Size (RFS) The condion where the tolerance of form, runout or locaon must be met irrespecve of where the feature lies within its size tolerance.
Roundness Describes the condion on a surface of revoluon (cylinder, cone, sphere) where all points of the surface intersected by any plane.
Runout Is the composite deviaon from the desired form of a part surface of revoluon through on full rotaon (360 deg) of the part on a datum axis.
Slope I s used to indicate slope for flat tapers. This symbol is always shown with the vercal leg to the le5.
Spherical Diameter Shall precede the tolerance value where the specified tolerance value represents spher- ical zone. Also, a posional tolerance may be used to control the locaon of a spherical feature relave to other features of a part. The symbol for spherical diameter precedes the size dimension of the feature and the posional tolerance value, to indicate a spher- ical tolerance zone.
Spherical Radius Precedes the value of a dimension or tolerance.
Spo6ace [ASME Y14.5-2009 Secon 1.8.14] Counterbore and spo9ace previously used the same symbol. A spo9ace now looks like the counterbore symbol with the addion of the le1ers SF.
Square Is used to indicate that a single dimension applies to a square shape. The symbol pre- cedes the dimension with no space between.
