General tolerances for Iinearand angular dimensions and geometrical=.tolerances

Transcription

1 oa / - UDC : 21 7 : 21 9 : DEUTSCHE NORM April 1991 General tolerances for Iinearand angular diensions and geoetrical= tolerances (not to be used for new destgns) '-j' ;,, DIN 718 Allgeeintoleranzen ; Langen- and Winkela8e,For and=lage& ' Supersedes May 1981 (nicht fur Neukonstruktionen) ' '7' 1 edition of DIN 718 Part 1 and July 198 This standard is not to be used for new designs General tolerances for these are now ced by ISO 278 Parts 1 and 2 See also clause 1 and the Explanatory notes In keeping with current practice in standards published by the International Organization for Standardization (ISO), a coa has been used throughout as the decial arker I - 01 a E x Z o W 9 E z C, o` 5 c c CL 0 - ~ o L C 3 r = v o c~ 0 1 Scope This standard is intended to ensure that all drawings prepared to date in which general tolerances have been specified on the basis of DIN 718 will reain intelligible and be interpreted correctly, and also to infor the user of this standard that, for all new designs, tolerances are to be specified on the basis of ISO 278 Parts 1 and 2 2 Field of application v = General tolerances as specified in this standard are z applicable for the diensions of parts produced by etal C reoval (i e chip reoval)'), unless this involves specia! v anufacturing processes for which other standards specifying general tolerances apply to apply General tolerances as specified here shall apply when reference is ade to this standard in drawings or associated docuents (e g delivery conditions) in accordance with clause 5 If special general tolerances are specified in accordance with other standards (cf page ), the standards concerned shall be indicated on the drawing or in the associated docuents If, in cases where production specifications contain references to ore than one standard on general tolerances, there is any doubt as to which standard is to apply for a given linear or angular diension, then the standard specifying the larger tolerance shall be deeed Accordingly, a diension between an unfinished and a finished surface on a blank (e g on a casting blank or forging blank), for which no individual tolerance has been L -o indicated, will be required to eet the general tolerance given in the relevant standard on blanks, provided that is A 0 indeed the larger tolerance However for a diension 0 Z between two finished surfaces, the general tolerance specified in DIN 718 shall always apply Production specifications in which linear or angular diensions (but not auxiliary diensions) appear without individually indicated tolerances shall be considered incoplete if there is no reference, or inadequate reference, to general tolerances General tolerances as specified in this standard apply for : a) linear diensions, such as external sizes, internal sizes, step sizes, diaeters, clearances (cf table 1), external radii and chafer heights for broken edges (cf table 2) ; b) angular diensions (cf table 3), both those indicated and those not usually indicated on drawings, such as 90 angles or the angles of regular polygons : c) linear and angular dirrfeensions produced by achining assebled parts : d) workpiece features for which no individual tolerances of for and position are indicated General tolerances as specified in this standard do not apply for : a) linear and angular diensions and workpiece features for which tolerances have been individually indicated ; b) linear and angular diensions and workpiece features for which other standards on general tolerances are specified in drawings or associated docuents ; c) auxiliary diensions enclosed in brackets (cf DIN 40 Part 2) ; d) theoretically exact diensions enclosed in rectangular fraes as specified in ISO 1101 ; e) angular diensions on circular graduations ; f) 90 angles, not indicated on the drawing, between lines foring coordinate axes : g) linear and angular diensions produced by the assebly of parts ; h) workpiece features which are not produced by reoval of aterial, in accordance with the indication of a seifinished product on drawings ') For concepts relating to anufacturing processes see DIN 8580 Continued on pages 2 to 7 Aft Beuth Verlag GbH, Berlin, has the exclusive right of sale for Geran Standards (DIN-Noren) 1091 DIN 718 Engl Price group 8 Sales No 0108 ' '

2 I I Page 2 DIN General tolerances for linear and angular diensions 3 1 Linear diensions Table 1 Perissible deviations for linear diensions, except for external radii and chafer heights Perissible deviations, in, for noinal sizes, in, fro 0,5') to f (fine) ± 0,05 I ± 0,05 ± 0,1 ± 0,15 ± 0 2 ± 0,3 ± 0,5 ± 0,8 - - (ediu) ±0,1 10,1 ±0,2 ±0,3 ±0,5 ±0,8 ±12 ±2 ±3 ± 4 I ± 5 I t g (coarse) ± 0,15- ± 0,2 ± 0,5 ± 0,8 ± 1,2 ± 2 ± 3 ~ ± 4 ± 5 ± ± 7 I ± 8 sg (very coarse) - ± 0,5 ± 1 ± 1,5 ± 2 ± 3 ± 4 ± ± 8 ± 10 ± 12 ± 12 ') For noinal sizes below 0,5, the deviations shall be indicated adjacent to the relevant noinal size Table 2 Perissible deviations for external radii, r (cf figure 1 for exaple), and chafer heights, h (cf figure 2 for exaple) f (fine) (ediu) g (coarse) sg (very coarse) 3 2 Angular diensions Perissible deviations, in, for noinal sizes, in fro 0,5 1 ) to ±0,2 ±0,5 ±1 _2 ±4 0,2 ±1 ±2 t4 ±8 For noinal sizes below 0 5, the deviations shall be indicated adjacent to the relevant noinal size General tolerances for angular diensions apply irrespective of the actual diensions of the lengths, i e the angular deviations ay occur both on workpieces with axiuaterial sizes and on workpieces with iniu-aterial sizes The upper and lower deviations do not liit the for deviations of the legs or surfaces foring the angle Note In the case of workpieces exhibiting deviations of for, the angle is defined by the direction of the straight lines or planes applied to the two angle legs under the iniu aterial conditions (cf ISO 1101 for the definition of the iniu condition) Table 3 Perissible deviations for angular diensions f (fine) (ediu) 4 General geoetrical tolerances 4 1 Tolerancing principle as specified in ISO 8015 General tolerances based on the tolerancing principle specified in ISO 8015 are only to be applied when the drawing concerned contains the reference 'Tolerancing to ISO 8015' Where that is the case the general geoetrical tolerances (i e the tolerances of for and position) apply independently of the actual local sizes of the workpiece feature Each individual tolerance requireent ust be et The general geoetrical tolerances ay thus also be applied even if the features are everywhere at their axiu aterial size For fits, the envelope requireent ust also be specified, and this shall be individually indicated on the drawings (cf Explanatory notes) General tolerances of for Straightness and flatness The general tolerances on straightness and flatness shall be as specified in table 4 s on straightness shall be selected fro the table on the basis of the length of the corresponding tine, while, for flatness tolerances, selection shall be based on the longer lateral length of the surface, or on the diaeter of the circular surface Circularity Perissible deviations, in units of angle, for noinal sizes of the shorter leg, in, 10 T 1 g (coarse) ± 1 30' sg (very coarse) = ±30'1±20' The general tolerance on circularity shall be equal to the nuerical value of the diaeter tolerance, but in no case shall it be greater than the respective tolerance on radial run-out given in table (cf Explanatory notes) i ±10' ± 5 ' ± 50' i ± 25' I ± 15' 1± 1 0' i 2-1 ± 30' ± 20'

3 11;1~b - C- DIN 718 Page 3 Table 4 General tolerances on straightness and flatness 4LM General tolerances on straightness and flatness, in, for a noinal size, in, of R 0,004 0,01 0,02 0,04 0,07 0, S 0,008 0,02 0,04 0,08 0,15 0,2 0,3 0,4 - T 0,025 0,0 0,12 0,25 0,4 0, 0,9 12 I 1,8 U 0,1 0,25 0,5 1,5 2,5 3,5 5 W* Cylindricity General tolerances on cylindricity have not been specified Note If the envelope requireent is to apply to fits with cylindrical surfaces, the diension concerned shall be identified by the sybol, (e g 0 25 or 0 25 H7 ([)) General tolerances of position Parallelis The liitation of the deviation in parallelis is given either by the general tolerances on straightness or flatness (cf subclause ), or by the tolerance on the distance between the parallel lines or surfaces, whichever is the greater The longer of the two features shall betaken as the datu If both features are of the sae noinal size, then either ay serve as the datu If, for functional reasons, these datu specifications are not perissible, then tho tolerance on parallelis shall be individually indicated as specified in ISO 1101 Note If the envelope requireent is to apply to fits with flat ating surfaces, then the diension concerned shall be identified by the sybol, as specified in ISO 8015 (e g 30 p, or 30 h 7 ) Perpendicularity and inclination General tolerances on perpendicularity and inclination have not been specified Instead, the general tolerances on angular diensions ay be applied (cf subclause 3 2) Syetry The general tolerances for syetrical, but not axially syetrical, features are to be taken fro table 5 These general tolerances also apply in cases where one of the syetrical features is axially syetrical and the other is not For general tolerances on syetry, the longer feature shall be taken as the datu That applies to all features which ay be referred to each other If both features are of the sae noinal length, then either ay serve as the datu If, for functional reasons, these datu specifications are not perissible, the tolerance on syetry shall,be Individually indicated as specified in ISO 1101 y v r ;141 Z4 ''Coax] alit ~ ; `-, General tolerances on coaxiality have not been speced 1The,deviatiortn coaxiality y i ian extree cases be as "!great{as,the ooleranca value for radial run-out given in table, since the deviation in radial run-out coprises the deviation in coaxiality and the deviation in circularity (cf Explanatory notes) Table 5 General tolerances on syetry Radial run-out The general tolerances on radial run-out shall be a : specified in table For general tolerances on radial runout, the bearing surfaces shall be taken as the datu, if they are designated as such Otherwise, the longer of the two features shall be taken as the datu If both features are of the sae noinal size, either ay serve as the datu If, for functional reasons, these datu specifications are not perissible, the tolerance on radial run-out shall be individually indicated as specified in ISO Axial run-out The general tolerances on axial run-out shall be as specified in table For general tolerances on axial run-out, the bearing surfaces shall be taken as the datu, if they are designated as such Otherwise, each of the axially syetric features ay serve as the datu Table General tolerances on radial and axial run-out Radial and axial run-out tolerances, in R 0,1 S 0,2 T 0,5 U 1 Syetry tolerance, in R 0,3 S 0,5 T 1 U 2

4 Page 4 DIN Tolerancing principle 'envelope requireent without indication on drawing' as specified in DIN General tolerances of for General tolerances of for have not been specified All deviations in for shall, if no individual tolerances of for have been indicated, be liited by the diensional tolerances as follows / 10~pr Shaft Cylinder B/ L Shaft e i In the case of shafts, the surface of the feature shall not exceed the geoetrically ideal for (cylinder) at its axiu aterial size (envelope requireent), nor shall the actual diension be saller than the least aterial liit at any point Note The cylinder at its axiu aterial liit is ebodied by the GO ring gauge Miniu liit of size Maxiu liit of size Maxiu liit of size Cyuncer,,-, Miniu liitl --- of size i Maxiu liit of size Maxiu liit of size _, ; -Miniu liit of size In the case of holes, the surface of the feature shall not be saller than the geoetrically ideal for (cylinder) at its iniu aterial size (envelope requireent), nor shall the actual diension be greater than the axiu aterial size at any point Note The cylinder at its iniu aterial liit of size is ebodied by the GO plug gauge General tolerances of position Parallelis For tolerances on parallelis, the specifications given in subclause shall apply analogously Table 7 General tolerances on syetry for non-axially syetrical workpiece features on syetry, in 02') Perpendicularity and inclination General tolerances on perpendicularity and inclination have not been specified Instead, the general tolerances for angular diensions ay be applied (cf subclause 3 2) Note Previously, the rule was that the deviations in perpendicularity should lie within the diensional tolerances easured in a rectangular syste of coordinates In practice however, this liitation was and is hardly ever observed in industry because it is seldo required for functional reasons 01) 0 15 A 0 3 B 0 5 C 1 D 2 ') Mainly applies for precision engineering applications Syetry For tolerances on syetry of non-axially syetrical workpiece features, the values specified in table 7 shall apply These tolerances on syetry shall also apply to relationships between workpiece features where one of the features is axially syetrical and the other is not The above syetry tolerances ay also obtain in the case of workpieces at their 'axiu aterial size' Radial and axial run-out For tolerances on radial run-out in the relationship of two or ore axially syetrical workpiece features, and for tolerances on axial run-out the values specified in table 8 shall apply

5 a DIN 718 Page 5 19 Table 8 General tolerances on radial run-out In the relationship between axially syetrical features, and general tolerances on axial run-out on radial and axial run-out, in 02') 0, ) 0,05 A a 0,1 B 0,2 C 0,5 D 1 ' Mainly applies for precision engineering applications The above tolerances on radial run-out ay also obtain in the case of workpieces at their' axiu aterial size', but this 4 does not apply to axial run-out tolerances, because axial run-out ust always lie within the linear tolerances 5 Designation and indication on drawings of general tolerances as specified in DIN Designation of general tolerances for diensions, only Exaple : DIN DIN nuber as per clause 3 of this standard 52 Designation of general tolerances based on ISO 8015 Exaple : DIN S DIN nuber as per clause 3 for size tolerance S as per subclause 4 1 for tolerances of for and position 53 Designation of general tolerances based on principle of `envelope requireent without indication on drawing' as per DIN 717 Exaple :

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