ISO 8015:1985 pdf download – Technical drawings – Fundamental tolerancing principle.
ISO 8015 spacifies the principle of the re-latiorship between dimenslonel flinear and angular) tolarancesand geometrical rolorances.
Field of application
The spacifieci principle shall be applied on technical drawdingsaind relatod tochnicall documents to
– linear dimansions and their tolerances;-angular dimensions and their tolerances;geomatrical toleranoes; which dafine the following four aspects for each feature of thapart :
-size;
-form;
-orientetion;-location.
3 References
Iso 286/1,So systero of lirowits anod fits – Part 1 : Bases oftolerances, devaBions and fits.1
ISO 1101，Tectricod cfranings – Geonetricel tolerancing-Talcrancing of formorieatation.lacaBon and run-out -Generaivies, cafirsvtions, symbals,indications on drawirngs.
lSO 2692，Techoacal drawsings – Geometricel toleraneing -Maocirratuarx materitl priraciple.分
4 Principle of independency
each spocified dimensionall or gaometricalrequirament on adrawding shal be met independleritly。unless a particular relatianship specified.
Therefore, wtere no rellationship is specified, the geametrical
tolorance applos rogardless of feature siza，and the two re-quirements are treated as being unrclated.
Consequontly, if a particuar rolationship of
-sizo and form, or
-size and orientation,or-sze and location
is requirod, it shall be speclfied on tha drawing isee clause 6).
5Tolerances
5.1Dimensional tolerances5.1.1 Linear tolerances
linear toleranca controls orntly the actual local sizes (two-pointmessurementsal of a feature. but not its farmn deviations (foreoample circularity and straightness deviations of a cyindricalfeature or flatness deviations of two parallal plana surfacesl.lSee ISO 286/1.J
Form deviations sthall, hoeraver, be controlled by the followsing :
-individuelly indicated form toleranoes;
一general geamatrical tolercnoes ;
-envelope requiremenn.
NOTE – For the purposes of this lneemationell Stendard,s singlefeature consists of a oylindrical murfece ar two patalll pline surfacas.
Thera is no control of the geometrical intervalatlonahip of individual
the sidios of a cube is not ccntrollod and, theirufore, it requires a perpen-features by the linspr tolerancas.For exampla, the porpendicularity ofcioularity tolarm nce dierated by the dosigo requiriment.
Foerm daviations shall, howwaver, be controllad by tha following:
-ineiviclsally incficated form tolerances;
-aneral geormetrical tolerances.
5.2Gaometrical tolarances
Geometrical tolerancos oontrol the deviation of the featurefram its theoretically exact
-form, or
-orientation,or-location
ragardless of the feature size.
The geomatrical tolerances will, therefore,apply indepondontlyof the actuall local sizes of individual features lsee clause 4).The geomatrical deviations may be at a maximum whether ornot tho crass-sections of tha recpoctive foatures are atmximum material size.
For instance, a shaft with maximum material size at any cross-soction may have a lobed form deviation within the circularitytoterance,and may also be bont by the amount of thostraighiness toleranoe lsee figures 2al and 2bH.