Group Standards Department ©
STANDARD Date
2008-08-22
en 1350 K Edition
Page
10
1 (19)
GENERAL GENERAL TOLERANCES AND STANDARD STA NDARD REFERENCES REFERENCES This standard endorses, for general tolerances, ISO 2768-1:1989 and ISO 2768-2:1989 Ad di ti on s t o ISO 2768-1:1989, s ee Table 1 an d Tab le 2 (n ot es 1, 2, 3 and 4). For drawi ngs w ith dr awing ow ner “ TOO” TOO” , see additi additi on to ISO 2768 2768-2:19 -2:1989 89 in Table 6 (note (note 5).
CONTENTS
D S G s t n e d m u s c g o / D m o d . r c a o d c n p a o t c S s a l e t a s / a / : b p t a t t a h k d L c s e R e t h o U t c N e n s n o u r i t t e t i o n d L I E - -
Page
1
GENERAL ..................................................................... ........................................................................................................... ................................................................. ............................................................ ................................. 2
2 2.1 2.2 2.3 2.3.1 2.3.1.1 2.3.1.2 2.4 2.4.1 2.4.2 2.4.2.1 2.4.2.2 2.4.2.3 2.4.3 2.4.3.1 2.4.3.2 2.4.3.3 2.4.3.4 2.4.3. 2.4.3.5 2.4.4 2.4.4.1 2.4.4.2 2.4.4.3 2.4.4.4 2.4.4.5 2.4.4.6 2.4.4. 2.4.4.7 2.4.5
GENERAL TOLERA NCES ................................... ......................................................................... ........................................................................... ................................................................. ............................... ... 2 GENERAL ................................... ......................................................................... ........................................................................... ................................................................. ............................................................ ................................ 2 REJECTION ...................................................................... ........................................................................................................... ................................................................. ............................................................ ................................ 3 LINEAR AND ANGULAR DIMENSIONS ..................................................................... ........................................................................................................... ............................................................... ......................... 3 Scope ....................................................................... ............................................................................................................ ................................................................. ................................................................. ....................................... 3 Linear dimensions ..................................................................... ........................................................................................................... ................................................................. ................................................ ..................... 3 Angular dimensions...................................................................................... dimensions........................................................................................................................... ................................................................. .............................. .. 4 GEOMETRICAL TOLERANCES .................................... .......................................................................... ........................................................................... ................................................................. ............................... ... 4 Definitions ..................................................................... ........................................................................................................... ................................................................. ............................................................ ................................. 5 Tolerances for si ngle features ..................................... ........................................................................... ........................................................................... .............................................................. ......................... 5 Straightness and flatness................................................................ flatness..................................................................................................... ................................................................. ........................................... ............... 5 Roundness ..................................... ........................................................................... ........................................................................... ................................................................. ...................................................... .......................... 5 Cylindricity ..................................................................... ........................................................................................................... ................................................................. ............................................................ ................................. 5 Tolerances for related features ................................... ......................................................................... ........................................................................... .............................................................. ......................... 5 Parallelism..................................................................................................... Parallelism............................................................... ................................................................. ................................................................. ........................................ 5 Perpendicularity ................................... ........................................................................ ........................................................................... ................................................................. ................................................ ..................... 5 Symmetry ....................................................................... ............................................................................................................ ................................................................. ............................................................ ................................ 6 Coaxiality................................................................................................. Coaxiality........................................................... .................................................................... ................................................................. .......................................... ....... 6 Circular run-out .................................... .......................................................................... ........................................................................... ................................................................. ................................................ .................... 6 Examples ....................................................................... ............................................................................................................ ................................................................. ............................................................ ................................ 7 General ..................................... .......................................................................... .......................................................................... ................................................................. ............................................................ ................................ 7 Roundness ..................................... ........................................................................... ........................................................................... ................................................................. ...................................................... .......................... 8 Cylindricity ..................................................................... ........................................................................................................... ................................................................. ............................................................ ................................. 8 Parallelism..................................................................................................... Parallelism............................................................... ................................................................. ................................................................. ........................................ 8 Symmetry ....................................................................... ............................................................................................................ ................................................................. ............................................................ ................................ 9 Drawing example ...................................................................... ........................................................................................................... ................................................................. ............................................... ................... 10 Interpretation of drawing example ..................................... .......................................................................... ........................................................................... ....................................................... ................. 10 Miscellaneous ...................................................................... ........................................................................................................... ................................................................. .................................................... ........................ 11
3 3.1 3.1.1 3.1.2 3.2 3.2.1 3.2.2 3.2.3 3.2.4 3.2.5 3.2.6 3.2.7 3.2.8 3.2.9 3.2.10 3.2.11 3.2.12 3.3 3.3.1 3.3.2
GENERAL STANDA RD REFERENCES ...................................... ........................................................................... ........................................................................... ........................................... ..... 11 GENERAL ................................... ......................................................................... ........................................................................... ................................................................. .......................................................... .............................. 11 Availability of standards ........................................................................ ............................................................................................................. ................................................................. ................................... ....... 11 ISO compared to AC-STD ..................................... ........................................................................... ........................................................................... ................................................................. .............................. 12 LIST OF STANDARDS ..................................... .......................................................................... ........................................................................... ................................................................. ........................................ ............. 12 Lines, arrows and dimensioning....................................................................................................... dimensioning.................................................................................................................................. ............................. .. 12 Text ..................................... .......................................................................... .......................................................................... ................................................................. ................................................................ .................................... 12 Project methods ................................... ........................................................................ ........................................................................... ................................................................. .............................................. ................... 12 Views and secti ons .................................................................................................. ............................................................................................................................... ..................................................... ........................ 12 Item references .................................... ......................................................................... ........................................................................... ................................................................. .............................................. ................... 13 Quantities and units ................................... ........................................................................ .......................................................................... ................................................................. ......................................... ............. 13 Symbols ................................... ......................................................................... ........................................................................... ................................................................. .......................................................... .............................. 13 Components and characteris tics ...................................................................... ............................................................................................................ ............................................................. ....................... 13 Dimensioning and tolerancing.................................................................... tolerancing.......................................................................................................... ................................................................. ............................. .. 14 Geometrical tolerancing .................................. ........................................................................ ........................................................................... ................................................................. ................................... ....... 14 Surface texture.................................................................... texture.......................................................................................................... ................................................................. .................................................... ......................... 14 Document handling .................................... ......................................................................... ........................................................................... ................................................................. ........................................ ............. 15 EXAMPLES OF DRAWING INDICATIONS................................... ........................................................................ ........................................................................... ....................................................... ................. 15 General standard references ..................................................................... ........................................................................................................... ................................................................. ............................. .. 15 Non general standard references ..................................................................... ........................................................................................................... ............................................................. ....................... 16
4 4.1 4.2 4.3 4.4 4.5
INDICATION ON DRAW INGS .................................... .......................................................................... ........................................................................... ............................................................ ....................... 17 GENERAL STANDARD REFERENCES ONLY ................................... ........................................................................ .......................................................................... ................................................. ............ 17 LINEAR AND ANGULAR DIMENSIONS ..................................................................... ........................................................................................................... ............................................................. ....................... 17 DIMENSIONAL TOLERANCES AND GEOMETRICAL TOLERANCES .................................. ....................................................................... ......................................................... .................... 17 GEOMETRICAL TOLERANCES ONLY ...................................................................... ............................................................................................................ ............................................................. ....................... 17 BOTH DIMENSIONAL, GEOMETRICAL AND ENVELOPE REQUIREMENTS.................................... .......................................................................... .............................................. ........ 17
5 5.1 5.2 5.3 5.4 5.4.1 5.4.2
OLDER DRA WING INDICATIONS ................................... ........................................................................ ........................................................................... ....................................................... ................. 18 LINEAR MEASURES ...................................................................... ............................................................................................................ ................................................................. .............................................. ................... 18 ROUNDING-OFF RADII AND CHAMFERS .................................. ....................................................................... ........................................................................... ....................................................... ................. 18 ANGULAR DIMENSIONS ...................................................................... ........................................................................................................... ................................................................. ......................................... ............. 18 OLD METHODS OF INDICATION .................................. ........................................................................ ........................................................................... ................................................................. .............................. 19 One tolerance cl ass ....................................................................................................... ................................................................................................................................... ............................................... ................... 19 Different tolerance classes .................................... .......................................................................... ........................................................................... ................................................................. .............................. 19
Group Standards Department ©
STANDARD Date
2008-08-22
1
en 1350 K Edition
Page
10
2 (19)
GENERAL General tolerances should be stated whenever required, with a reference to AC-STD 1350 K, with ISO tolerance class (-es) added, according to paragraph 2, page 2 for linear and angular dimensions and paragraph 2.4, page 4 for geometrical tolerances. Reference to AC-STD 1350 K, without stating of tolerance class, means that general standards under paragraph 3, page 11 can be applied on a drawing without any reference stated. ISO 2768-1:1989 and ISO 2768-2:1989 mainly applies to features produced by material removal or formed from sheet metal. For indications on drawings, see example under paragraph 4, page 16.
2
GENERAL GENERAL TOLERANCES
2.1
General All features on component component parts always always have a size and a geometrical geometrical shape. For For the deviation deviation of size and for the deviations of the geometrical geometrical characteristics (form, orientation and location) the function of the part requires limitations which, when exceeded, impair this function. General tolerances are tolerances which shall apply where no other tolerances have been indicated. This standard mainly applies to features which are manufactured by removal of material. If there are general tolerances for other processes, as specified in other standards, reference shall be made to them on the drawings or associated specifications. For a dimension between an unfinished and a finished surface, e.g. of cast or forged parts, for which no individual tolerance is directly indicated, the larger of the two general tolerances in question applies. The tolerancing on the drawing should be complete to ensure that the elements of size and geometry of all features are controlled, i.e. nothing shall be implied or left to judgement in the workshop or in the inspection department. The use of general tolerances for size and geometry simplifies the task of ensuring that this prerequisite prerequisite is met. ISO tolerance class (classes) for general tolerances should be used when the values in question correspond correspond to the customary workshop accuracy. If tighter limits are required, or if larger deviations are permitted, the tolerances should be indicated directly on the drawing. When selecting the tolerance class, the respective customary workshop accuracy has to be taken into consideration. If smaller tolerances are required or larger tolerances are permissible and more economical for any individual feature, such tolerances should be indicated adjacent to the relevant nominal dimension (s). The use of general tolerances provides the following advantages: a) drawings are easier to read and thus communication communicat ion is made more effective effecti ve to the user of the drawing. b) the design draughtsman draughtsman saves time by by avoiding detailed detailed tolerance tolerance calculations. calculations. It is sufficient enough to know that the function allows a tolerance greater than or equal to the general tolerance. c) the drawing readily indicates which feature can be produced by normal process capability. capability . d) assists quality quality engineering engineering by reducing reducing inspection inspection levels. levels. e) those dimensions dimensions remaining, remaining, which have have individually individually indicated tolerances, tolerances, will, for for the most part, part, be those controlling features for which the function requires relatively small tolerances. This will be helpful for production planning and will assist quality control services in their analysis of inspection requirements. f) purchase and sub-contract supply engineers can negotiate orders more readily since the “customary workshop accuracy” accuracy” is known before the contract is placed. This also avoids discrepancies on delivery between the buyer and the supplier, since in this respect the drawing is complete. These advantages are fully obtained only when there is sufficient reliability that the general tolerances will not be exceeded, i.e. when the customary workshop accuracy of the particular workshop is equal to or finer than the general tolerances indicated in the drawing.
Group Standards Department ©
STANDARD Date
en 1350 K Edition
Page
10
3 (19)
2008-08-22 The workshop should, therefore: – –
measure and and determine determine the workshop workshop accuracy. accept only those drawings having having general general tolerances tolerances equal to or or greater than its customary workshop accuracy. check by sampling sampling that its customary customary workshop accuracy does not deteriorate.
–
2.2
Rejection The tolerance which the function allows is often greater than the general tolerance. The function of the part is, therefore, not always impaired when the general tolerance is (occasionally) (occasionally) exceeded at any feature of the work-piece. Exceeding the general tolerance should lead to a rejection of the work-piece only if the function is impaired.
2.3
Linea r and angular dimensions General tolerances for linear and angular dimensions apply when drawings or belonging specifications refer to ISO tolerance classes f, m, c or v (ISO 2768-1:1989). NOTE:
2.3.1
For drawing indications, see paragraph 4, page 16. For older tolerance classes (1, 2, 3, and 4), see paragraph 5, page 17.
Scope Paragr aph 2.3 2.3 spe specifi cifie es ge general tole tolerrances ces for for lin linear an and an angular lar d imensions without individual tolerance indications in four tolerance classes. The standard applies to the dimensions of parts that are produced by metal removal or parts that are formed from sheet metal. This part of AC STD 1350 K only applies for the following dimensions which do not have an individual tolerance indication: a) linear dimensions, e.g. external sizes, internal sizes, step sizes, diameters, radii, distances, external radii and chamfer heights for broken edges. b) angular dimensions, includin g angular dimensions usually not indicated, e.g. right angles (90 ⁰), unless reference to AC-STD 1350 K paragraph 2.4 is made, or angles of uniform polygons. c) linear and angular dimensions produced by machining assembled parts. The standard does not apply for the following dimensions: a) linear and angular dimensions which are covered by reference to other standa rds on general tolerances. b) auxiliary dimensions indicated in brackets. c) theoretically theoretical ly exact dimensions indicated in rectangular frames.
2.3.1.1
Linear dimensions General tolerances for linear dimensions are given in tables 1 and 2. Values in millimetres.
Table 1. Permissible deviations for lin ear dimensions except for broken edges, see also table 2). Tolerance class Desig-nation
Description
Permissible Permissible deviations f or basic size range range
-3
1)
>3 -6
>6 -30
>30 -120
>120 -400
>400 -1000
>1000 -2000
>2000 -4000
>4000 2) -8000
>8000 2) -12000
>12000 2) -16000
>16000 2) -20000
f
fine
±0,05
±0,05
±0,1
± 0,15
±0,2
±0,3
±0,5
–
–
–
–
–
m
medium
±0,1
±0,1
±0,2
±0,3
±0,5
±0,8
±1,2
±2
±3
±4
±5
±6
c
coarse
±0,2
±0,3
±0,5
±0,8
±1,2
±2
±3
±4
±5
±6
±7
±8
v
very coarse
–
±0,5
±1
±1,5
±2,5
±4
±6
±8
±8
±10
±12
±12
1)
2)
In ISO 2768-1:1989 1:1989 0,5 mm mm ha ha s been been indicated as th the smallest basic size in the table, and also that individual tolerances al ways must be indi indica catted for for smal smalle lerr basi basic c size sizes. s. However, ver, within the Atla Atlas s Cop Copco grou group, p, it has has been been decided t hat the indi indica cate ted d devi deviat atio ions ns are are appl applic icab able le also for basic sizes smaller than 0,5 mm, in order to facilitate the interpretation of older drawings. Not included in ISO 2768-1:1989, but constitutes a Swedish addition in SS-ISO 2768-1:1990.
Group Standards Department ©
STANDARD
en 1350 K
Date
Edition
Page
10
4 (19)
2008-08-22
3)
Table 2. Permissible deviations for broken edges (internal
, external
radii and chamfer heights)
Note: If general requirements according to AC-STD 1436 K have been stated, those requirements apply.
Tolerance class
3) 4)
4)
Designation
Description
f
Fine
m
Medium
c
Coarse
v
Very coarse
Permissible Permissible deviations for basic size range 3)
≦3
4)
>3-6
>6
±0,2
±0,5
±1
±0,4
±1
±2
4)
Internal radii and chamfer heights are not included in ISO 2768-1:1989, but w ithin Atlas Copco it h as been decided to do that. For sh shar p c or or ne ner s in gr grooves, wi wi th thout radius dimens io ion, ma max al al lo lowed ra radius is is 0, 0,2 mm mm. Fo For ot other sh sh arp corners , radi us us 0, 0,4 mm mm is is al all ow owed. In ISO 2768-1:1989 0,5 0,5 mm has been indicated as the smallest basic size in the table, and also that individual tolerances always must be indicated for smaller basic sizes. However, within the Atlas Copco group, it has been decided that the indicated deviations are applicable also also for for basi basic c size sizes s sma small ller er than than 0,5 0,5 mm, mm, in orde orderr to faci facili litate the inte interp rpre reta tati tion on of older der draw drawin ings gs.. For new drawings, and for drawin g modifications, it is recommended that, normally general, requirements according to AC-STD 1436 K are indicated for edges, corners, and when required, also for radii.
2.3.1.2
Angular dimensions General tolerances specified in angular units control only the general orientation of lines or line elements of surfaces, but not their form deviations. The general orientation of the line derived from the actual surface is the orientation of the contacting line of ideal geometrical form. The maximum distance between the contacting line and the actual lin e shall be the least possible value, see figure 1. The permissible deviations of angular dimensions are given in table 3.
Contacting line
45⁰ (± Permissible deviations)
Actual lines Contacting line
Figure 1. Example 45°angle. Table 3. Pe Permissible deviations of angular dimensions. Tolerance class
2.4
Designation
Description
f
fine
m
medium
c v
Permissible Permissible deviations for ranges of lengths in mi llimeters, of the shorte shorterr side side of th e angle angle concer concerne ned d -10 >10-50 >50-120 >120-400 >400 ±1°
±0°30’
±0°20’
±0°10’
±0°5’
coarse
±1°30’
±1°
±0°30’
±0°15’
±0°10’
very coarse
±3°
±2°
±1°
±0°30’
±0°20’ ±0°20’
Geometri Geometri cal tol erances General geometrical tolerances a pply when dra wings or a ssociated spe cifications refer to ISO tolerance class H, K or L (ISO 2768-2:1 989). They apply to elements that do not have individual geometrical tolerance indications. Note: For drawing indications, see paragraph 4, page 16.
When selecting the tolerance class, the respective customary workshop accuracy has to be taken into consideration. If smaller tolerances are required or larger tolerances are permissible
Group Standards Department ©
STANDARD Date
en 1350 K Edition
Page
10
5 (19)
2008-08-22
and more economical f or any individual feature, such tolerances should be indicated according to AC-STD 4551 K. General geometrical tolerances apply to all geometrical tolerance characteristics, excluding cylindricity, profile of any line, profile of any surface, angularity, angularity, coaxiality, positional tolerances tolerances and total run-out. General geometrical tolerances in accordance with this standard should always be indicated. 2.4.1
Definitions For the purposes of t his standard, the definitions given in AC-STD 4551 K and AC-STD 4552 K apply.
2.4.2
Tolerances for single features
2.4.2.1
Str aightness and flatness When a toler ance is selected from table 4, it shall be based, in the case of straightness, on the length of the corresponding line and, in the case of flatness, on the longer lateral length of the surface, or the diameter of the circular surface. Table 4. General tolerances on straightness and flatness. Tolerance class
2.4.2.2
Straig htness and flatness tolerances tolerances for ranges of nominal length –10
>10–30
>30–100
>100–300
>300–1000
>1000–3000
H
0,02
0,05
0,1
0,2
0,3
0,4
K
0,05
0,1
0,2
0,4
0,6
0,8
L
0,1
0,2
0,4
0,8
1,2
1,6
Roundness The gene genera rall tole tolera rance on roundnes dness s is equal to the numerical value of the di ameter tolerance, but in no case shall it be greater than the respe ctive tolerance value for circular radial run-out given in table 7, page 6. 6. See als o example in paragraph 2.4.4.2, pa ge 8.
2.4.2.3
Cylindricity General tolerances ar e not spec ified. Note: The cylin dricity deviation comprises three components: roundness deviation, straightness deviation and parallelism deviation of opposite generator lines. Each of these components is controlled by its individually indicated tolerance or its general tolerance. If, for functional reasons, the cylindricity deviation has to be smaller than the combined effect (see paragraph 2.4.4.3) of the general tolerances on roundness, straightness and parallelism, an indivi dual cylindricity tolerance in accordance with AC-STD 4551 K should be indicated for the feature concerned. In some cases, e.g. in the case of a fit, the indication of the envelope requirement paragraph 4.5, page 17
2.4.3
is appropriate, see
Tolerances for related features The tolerances specified in paragraph 2.4 .3.1 – 2.4.3.5 apply to all features, which are in relation to one another and which have no respective individual indication.
2.4.3.1
Paralleli sm The general tolerance on parallelism is equal to the numerical value of the size tolerance or the flatness/straightness ss/straightness tolerance, whichever is greater. The longer of the two features shall be taken as the datum. If the fea tures are of equal nominal length, either may be taken as the datum, see paragraph 2.4.4.4, page 8.
2.4.3.2
Perpendicularity The genera l tolerances on perpendicularity are given in table 5. The longer of the two sides forming the right angle shall be taken as the datum. If the sides are of equal nominal length, either may be taken as the datum.
Group Standards Department ©
STANDARD
en 1350 K
Date
Edition
Page
10
6 (19)
2008-08-22 Table 5. General tolerances on perpendicularity. Tolerance class
2.4.3.3
Perpendicularity Perpendicularity to lerances for ranges of nominal lengths of the shorter side –100
>100–300
>300–1000
>1000–3000
H
0,2
0,3
0,4
0,5
K
0,4
0,6
0,8
1
L
0,6
1
1,5
2
Symmetry The general tolerances on symmetry are given in table 6. The longer of the two features shall be taken as the datum. If the features are of equal nominal length, either may be taken as the datum. Note: The general tolerances on symmetry apply where at least one of the two features has a median plane, or the axes of the two features are perpendicular to each other.
See examples in paragraph 2.4.4.5, page 9. Table 6. General tolerance on symmetry Tolerance class
Symmetry Symmetry tolerances for ranges of no minal lengths of the shorter side –100
>100–300
H
0,5
K L
>300–1000
0,6
5)
5)
0,6
>1000–3000
1
0,8
1
1,5
2
Note: Note: When changing an old tolerance class, see paragraph paragraph 5 page 17, symmetry tolerances according to AC-STD 4551 K (ISO 1101:2004) may be required for some dimensions. 5)
2.4.3.4
For all all drawings with drawing owner owner “TOO“ the general tolerance tolerance for for symmetry is 0,2 mm, unless otherwise otherwise indicated.
Coaxiality General tolerances are not specified. Note: The deviation in coaxiality may, in extreme cases, be as great as the tolerance value for circular radial run-out given in table 7, since the deviation in radial run-out comprises the deviation in coaxiality and the deviation in roundness.
2.4.3.5
Circular run-out The general tolerances on circular run-out are given in table 7. For general tolerances on circular run-out, the bearing surfaces shall be taken as the datum. Otherwise, for circular radial run-out, run-out, the longer of t he two features shall be taken as the datum. If the features are of equal nominal length, either may be taken as the datum. Table 7. General tolerances on circular run-out. Tolerance class
Tolerances Tolerances on ci rcular run-out
H
0,1
K
0,2
L
0,5
Group Standards Department ©
STANDARD Date
2008-08-22 2.4.4
Examples
2.4.4.1
General
en 1350 K Edition
Page
10
7 (19)
According to the principle of independency (AC-STD 4555 K) general geometrical tolerances tolerances appl apply y ind indep epe enden ndentl tly y of of the the actu actual al loca locall siz size e of of the the wor workk-piece fea featu ture res. s. Accordin rdingl gly, y, the the gen gener eral al geometrical tolerances may be used even if the feature s are at their maximum material size everywhere, see figure 2 below. If the envelope requirement (AC-STD 4555 K) is indi vidually indicated adjacent to the feature or generally to all features of size as described in paragraph 4.5, page 17, this requirement should also be complied with.
General tolerances AC-STD 1350 K -mH
Maximum limit of size
Maximum roundness deviation resultin from a lobed form Note: The value 0 ,1 mm comes from table7, page 6. See also paragraph 2.4.2.2, page 5.
Maximum straightness deviation
Maximum limit of size Figure 2. Priciples of independency; maximum permissible deviations on the same feature.
Group Standards Department ©
STANDARD Date
en 1350 K Edition
Page
10
8 (19)
2008-08-22 2.4.4.2
Roundness See figure 3 and 4. (See also paragraph 2.4.2.2, page 5.) In figure 3, the permissible deviation of the diameter is indicated directly on the drawing. The general tolerance on roundness is equal to the numerical value of the diameter tolerance, since the value in table 7, page 6 is larger. Indication on the drawing
Roundness tolerance zone
AC-STD 1350 1350 K -K Figure 3. Example of gener al tolerance on roundness. In figure 4, the permissible deviat ion of the diameter is according to the general tolerance for AC-STD 1350 K –mK. The permissible permissible deviations deviations for the diameter of of 25 mm are ± 0,2 mm. These deviations lead to the numerical value of 0,4 mm, which is greater than the value of 0,2 mm given in table 7, pag e 6. The value of 0,2 mm, therefore, applies for the rou ndness tolerance. Indication on the drawing
Roundness tolerance zone
AC-STD 1350 1350 K -mK Figure 4. Example of general tolerance on roundness. 2.4. 2.4.4. 4.3 3
Cylindricity city The combined effect of the general tolerances of roundness, straightness and parallelism is, for geometrical reasons, smaller than the sum of the three tolerances since there is also a certain limitation by the size tolerance. However, in order to decide whether the envelope requirement or an individual cylindricity cylindricity tolerance is to be indicated, the sum of the three tolerances can be taken into account.
2.4.4.4
Parallelism Depending on the shapes of the deviations of the features, the parallelism deviation is limited by the numerical value of the size tolerance, see figure 5, or by the numerical value of the straightness or flatness tolerances, see figure 6.
Group Standards Department ©
STANDARD
en 1350 K
Date
2008-08-22 Dimensional tolerance
Page
10
9 (19)
Straightness tolerance
Figure 5. Parallelism Parallelis m deviation equal to the numerical value of the size tolerance t olerance 2.4.4.5
Edition
Figure 6. Parallelism deviation equal to the numerical value of the straightness tolerance
Symmetry See example figure 7.
a) Datum: longer feature (l ( l2)
b) Datum: longer featu re (l1)
c) Datum: longer feature (l ( l2)
d) Datum: longer feature (l ( l1) Figure 7. Examples of general tolerances on symmetry. Note: According to ISO 1101:2004 (Annex A) references now should always be stated stated with a reference letter. Direct reference as shown in this figure (IS O 2768-2:1989) 2768-2:198 9) is no longer permitted.
Group Standards Department ©
STANDARD
en 1350 K
Date
2008-08-22 2.4.4.6
Edition
Page
10
10 (19)
Drawing example
Figure 8. Drawing example (reference to 1350 K -mH). -mH ). 2.4.4.7
Interpretation Interpretat ion of drawing example
1)
1)
According to ISO 1101:2004 (Annex A) references now should always be stated with a reference letter. Direct reference as shown in this figure (ISO 27682:1989) is no longer permitted
Note: The tolerances shown in chain thin dashed lines (boxes and circles) are general tolerances. These tolerance tolerance values would be automatically achieved by machining in a workshop with a customary accuracy equal to or finer than AC-STD 1350 K -mH and would not normally r equire to be inspected. As some tolerances also limit the deviations of other characteristics of the same feature, e. g. the perpendicularity tolerance also limits the straightness deviations, not all general tolerances are shown in the interpretations above.
Figure 9. Interpretation of drawing example.
Group Standards Department ©
STANDARD Date
2008-08-22 2.4.5
en 1350 K Edition
Page
10
11 (19)
Miscellaneous General tolerances should be indicated on the drawing by referring to this part of (AC STD 13 50 K) in accordance with paragraph 4, page 16. The values of gen eral tolerances correspond to tolerance classes of customary workshop accuracy. The app ropriate tolerance class should be selected and indicated on the drawing. Above a certain certain tolerance value, which correspond corresponds s to the customary customary workshop accuracy, there is usually no gain in manufacturing economy by enlarging the tolerance. In any event, workshop machinery and the usual workmanship normally do not manufacture features with greater deviations. For example, a feature having a 35 mm diameter could be manufactured to a high level of conformance in a workshop with ”customary medium accuracy”. Specifying a tolerance of ± 1 mm would be of no benefit in this particular workshop, as the general tolerance values of ± 0,3 mm would be quite adequate. A feature of 25 mm ± 0,1 mm diameter by 80 mm long manufactured in a workshop with a customary accuracy equal to or finer than AC STD 1350 K – mH contains the geometrical deviations well within 0,1 mm for roundness, 0,1 mm for straightness of surface elements, and 0,1 mm for circular radial run-out (the values given have been taken from this part of AC STD 1350 K). Specifying tolerances would be of no benefit in this particular workshop. However, if, for functional reasons, a feature requires a smaller tolerance value than the general tolerances, then that feature should have the smaller tolerance indicated individually individually adjacent to the particular feature. This type of tolerance falls outside t he scope of general tolerances. tolerances. In cases where the function of a feature allows a geometrical tolerance equal to or larger then the general tolerance values. This should not be individually indicated, but should be stated on the drawing as described in paragraph 4, page 16. This type of tolerance allows full use of the concept of general geometrical tolerancing. There will be “exceptions to the rule” whereby the function allows a larger tolerance than the general tolerances, and the larger tolerance will provide a gain in manufacturing economy. In these special cases, the larger geometrical geometrical tolerance should be indicated individually individually adjacent to the particular feature, e.g. the roundness tolerance of a large and thin ring.
3
GENERAL STANDARD STANDA RD REFERENCES In paragraph 3.2.1 - 3.2.12 below, standards have been listed, which normally can be applied on Atlas Copco drawings and manufacturing manufacturing documents without any specific references to the concerned standard documents. Please note that, the conditions required, for such general standard references, is that a reference to this standard (AC-S TD 1350 K) has been made on the drawing.
3.1
General In order to be able to interpret dimensioning, symbols, etc. on a drawing, it is necessary that references are made to the applied standards. Those references may be very extensive, making it more difficult to read the drawing. Therefore, a list of general standard references has been added to this standard. When other other standar standards ds than than those those listed listed below below are applied applied,, a refere reference nce to th ose standard standards s must must always be made, if the standard documents are needed for interpretation of the stated requirements. Note: If all required dimensions, etc. in a standard have been stated on the drawing, a reference to the applied standard is normally not necessary.
3.1.1
Availability of standards All Atlas Copco standards standards listed below below are internally internally available available in database database ”Standard ”Standard Documents - GSD”, and externally for subsuppliers on internet: www.atlascopco.com/gsd Note: When searching Atlas Copco standards on internet, only the standard number, e.g. 1350 K (a K (a single space between the number and capital ”K”) should be stated, witho ut any additions.
External standards (ISO, DIN, etc.) are available or ca n be ordered for use with in the Atlas Copco Group via database ”External Standards 2.0 - GSD”. Because of licence agreements, external standards standards must not be placed at disposal by Atlas Copco to subsuppliers. subsuppliers.
Group Standards Department ©
STANDARD Date
2008-08-22 3.1.2
en 1350 K Edition
Page
10
12 (19)
ISO compared to AC-STD Earlier, Atlas Copco internal standards standards (AC-STD) were always created, when required. They still exist to a large extent, and are mainly based on international standards (ISO). There also exist Atlas Copco standards standards without without any connection connection to external standards. Today, the ambition is, to a higher degree, to apply external standards directly. When required external standards, preferably ISO, can be endo rsed through simplified Atlas Copco standards, containing comm ents about application, additions, exclusions, etc.
3.2
Lis t o f standards Standards, and other information, shown within bra ckets in the t ables below, are for information only, and should normally only be used with a reference to concerned standard, e.g. ISO 128 23 must be referred to when used.
3.2.1
Lines, arrows and dimensioning ISO
AC-STD
128-1
Index
128-20
Basic conventions for lines
128-21
Lines in CAD systems
128-22
1211 K
(128-23) 128-24
3.2.3
1211 K, 1312 K
No informative divergences. Mechanical designs (shipbuilding)
129-1
1420 K
No informative divergences, besides threads, which also are included in 1420 K. Dimensioning
ISO
AC-STD
Comment s
3098-0
1212 K
No informative divergences. Lettering - General requirements
3098-2
1212 K
No informative divergences. Latin alphabet
Text
3098-3
Greek alphabet
3098-4
Diacritical and particular marks for the latin alphabet
3098-5
CAD lettering of the latin alphabet
3098-6
Cyrillic alphabet 1213 K
Writing rules
AC-STD
Comment s
Project methods ISO
3.2.4
No informative divergences. Leader lines and reference lines (constructions)
(128-25)
3.2.2
Comments
5456-1
Synopsis
5456-2
Orthographic representations
5456-3
Axonometric representations
5456-4
Central projection
10209-2
Terms
Views and sections ISO
AC-STD
Comment s
128-30
1310 K
No informative divergences. Basic conventions for views
128-34
1310 K
No informative divergences. Views for mechanical designs
128-40
1311 K
No informative divergences. Basic conventions for cuts and sections
128-44
1311 K
No informative divergences. Sections for mechanical designs
Group Standards Department ©
STANDARD Date
en 1350 K Edition
Page
10
13 (19)
2008-08-22 1311 K
No informative divergences. Basic conventions for for representing areas on cuts and sections
ISO
AC-STD
Comment s
6433
1910 K
Certain divergences, but no contradiction. Parts list
128-50
3.2.5
3.2.6
3.2.7
Item references
Quantities Quantities and units ISO
ACSTD
Comments
31-0 - 31-13, 1000
2131 K
Certain divergences, divergences, but no contradiction. (ISO 31-3 = Mechanical designs)
Symbols ISO
AC-STD
701
3.2.8
Comment s Gears - Symbols for geometrical data
1043-1
2051 K
No informative divergences. Plastics - Symbols
1219-1
1280 K
No informative divergences. Symbols for fluid diagrams
3952-1 3952-4
Kinematic diagrams
5784-1 5784-3
Symbols for fluid diagrams, logic functions
81714-1
Design of graphical symbols
Components and characteristics ISO
ACSTD
Comments
68-2
3514 K
No informative divergences. UNC threads
228-1
3524 K
No informative divergences. Pipe threads (G)
3514 K
No informative diver gences. UNC threads
3517 K
No informative divergences. UNF threads
272, 4762
4341 K
No informative divergences. Widths across flats
273
4361 K 4361 A
No informative divergences. Clearance holes for bolts and screws Note: 4361 A
2162-1,-2,-3
1330 K
No informative divergences. Springs
2203
1330 K
No informative divergences. Gears
2306
6272 K
No informative divergences. Drill diameters for threads
2553
6890 K
No informative divergences. Welding symbols
2901
3544 K
No informative divergences. Trapetzoidal threads
2901, 2902, 2903, 2904
3545 K
No informative divergences. Trapetzoidal threads
263
5261 5455
is mainly intended for business line CT (Airpower)
Bars and profile sections 1210 K
5845-1
No informative divergences. Scales (for CAD other scales are permitted) Assembly of parts with fasteners
6410-1
1330 K
No informative divergences. Threads
6410-2
1330 K
No informative divergences. Thread inserts
6410-3
1330 K
No informative divergences. Threads, simplified representation
6413
1330 K
No informative divergences. Splines
8826-1, -2
1330 K
No informative divergences. Rolling bearings
9222-1, -2
1330 K
No informative divergences. Seals
(13715)
1436 K
Major informative divergences. Edges and corners. (1436 K includes additions to ISO.)
Group Standards Department ©
STANDARD Date
2008-08-22 14660-2
en 1350 K Edition
Page
10
14 (19)
Extracted median line of a cylinder and a cone ..., etc.
Note: Examples of stan dards which require a reference: (ISO 4063) AC-STD 6885 K, numerical codes for welding, etc. (ISO 5817) AC-STD 6892 K, quality levels for welding, etc. (ISO 6411) AC-STD 4251 K, cent re holes. (Normally centre holes a re permitted, bu t not required, when no reference to standard has been made.) (ISO (ISO 6520-1) AC-S AC-STD TD 6 892 892 K, K, qua quali lity ty leve levels ls for for weld weldin ing, g, etc. etc.
3.2.9
Dimensioning and tolerancing ISO
ACSTD
Comments Standard reference temperature for geometrical product specification and verification
1 129-1
1420 K
No informative divergences. Dimensioning
286-1, -2
4501 K
No informative divergences. ISO system of limits and fits
406
1305 K
No informative divergences. Tolerancing of linear and angular dimensions
1660
Dimensioning and tolerancing of profiles
3040
4031 K
Dimensioning and tolerancing of cones
(3302-1, -2)
1359 K
Major informative divergences. Rubber
3508
4316 K
No informative divergences. Thread run outs
(4753)
4331 K
Flat screw ends with chamfer. (ISO 4753 not specifically for chamfers)
6410-1
1330 K
No informative divergences. Threads
7083 8015
Geometrical tolerances, proportions of symbols 4555 K
No informative divergences. Relation between dimensional tolerances and geometrical tolerances
10135
Castings
TR 16015
Vocabulary of metrology
TR 14638, TS 17450-1, TS 17450-2
Geometrical Product Specification (GPS)
Note: Examples of standards which require a reference: (ISO 2768- 1, -2) 1350 K, i.e. i.e. this this standa standard, rd, which which has to be refere referenced nced to a pply. (ISO 8062) AC-STD 6131 K, dimensional tolerances and machining allowances on castings. ISO 10579, non-rigid parts. It is considered neccessary to reference this standard, by the note (ISO 10579-NR), whenever it is applied.
3.2.10
Geometrical tolerancing ISO
AC-STD
Comment s
1101
4551 K
Minor divergences, see ISO 1101 Annex A. Tolerances of form and position
2692
4553 K
No informative divergences. Maximum material principle (ISO also include ”Least material requirement”)
5458
4551 K
No informative divergences. Positional tolerancing
5459
4552 K
No informative divergences. Datums and datum systems
7083
Geometrical tolerancing, symbol proportions
14660-1, -2
Geometrical features
10578
3.2.11
4551 K
No informative divergences. Projected tolerance zone
Surface texture ISO (1302, 4287)
ACSTD 1254 K
Comments Major divergences. 1254 K follows older ISO edition. Surface texture
Group Standards Department ©
STANDARD Date
en 1350 K Edition
Page
10
15 (19)
2008-08-22
3.2.12
3098-3
Greek alphabet
3274, 4287, 4288
Profile method
8785
Surface imperfections
10135
Castings
11562
Profile method - Phase correct filters
12085
Motif Parameters
13565-1, -2, -3
Profile method - Filtering, Height characterization, etc.
14253-1, TS 14253-2, TS 14253-3
Inspection. Measuring equipment
14660-1
General terms and definitions. Geometrical Product Specifications (GPS)
Document handling ISO
AC-STD
Comment s
5457
1120 K
No informative divergences. Sizes of drawing sheets
1511 K
Abbreviations for used CAD system
(6428)
2602 K
Major divergences. Requirements for microcopying
(7200)
1220K, 2342 K
Major divergences, but no contradiction. Title blocks and document headers
(7573)
1910 K
Major divergences, but no contradiction. Parts list (Item lists)
(11442)
1102 K
Major divergences. Secrecy of drawi awings ngs
11442 (16016)
3.3 3.3.1
Document management 1102 K
Major divergen ces. Secrecy of drawings
1010 K
Drawing principles
1016 K
Transfer of drawing ownership - Original drawings/CAD models
1100 K
Filing drawings
1220:01 K
Drawings subject for authority approval
3391 K
Guidelines for design, notification, release, modification and withdrawal order
Ex am p l es o f d r aw i n g indica indicatti ons General standard re ferences Below, is tabulated a selectio ction n of com commonly used sed drawi rawin ng indi ndicati catio ons . Those indications may be used without any reference to concerned standards, under the condition that a reference h as been made to AC-STD 1 350 K.
Group Standards Department ©
STANDARD Date
2008-08-22
3.3.2
en 1350 K Edition
Page
10
16 (19)
Non general standard references Below, for information only, are shown th ree examples of drawing indications, which always require standard references. Ex am p l es of drawi ng indications
ISO ISO
8062
AC-ST AC-STD D
6131 K
Co m m en t s
Castings. System of dimensional tolerances and machining allowances
Tolerances of Form and position for ”Non-Rigid parts”
10579
1254:03 K
Surface character for sharp peaks
Group Standards Department ©
STANDARD Date
2008-08-22
4
en 1350 K Edition
Page
10
17 (19)
INDICATION ON DRAWINGS Indication on drawings, with ref erence to this standard (AC-STD 1350 K) should be made in the title block on most drawings within the Atlas Copco Group. Hereby, general references to all standards stated in paragraph 3, page 11 always apply. The standard designation designation (1350 K) may be stated with or without ISO tolerance classes (se below), but in order for the gene ral tolerances to be applicable ISO tolerance classes has to be indicated. Note: ISO tolerance classes are shown under paragraph 2.3, page page 3 for linear and angular dimensions, and according to paragraph 2.4, page 4 for geometrical tolerances.
4.1
Gener al standard references only If general tolerances are not applicable, but general standa rd references according to paragraph 3, page 11 are required, this shall be indicated according to the example below.
4.2
Linear and angular angular di mensions If general standard references and general tolerances for only linear and angular dimensions in accordance with AC STD 1350 K shall apply, reference to this sta ndard and ISO tolerance class shall be indicated according to example below.
Note: For ISO tolerance classes (f, m, c, v), see table 1-3, page 3-4
4.3
Dimensional tolerances and geometrical tolerances If general standard references and general linear and angular tolerances together with general geometrical geometrical tolerances shall apply, reference to this standard followed by ISO tolerance classes shall be indicated according to example below.
Note: In this case the general tolerances for right angles (90°), paragraph 2.3, 2.3, do not apply, because paragraph 2.4 2.4 specifies general tolerances on perpendicularity. For ISO tolerance classes (f, m, c, v and H, K, L ), see table 1 - 7, page 3 - 6.
4.4
Geometri Geometri cal tol erances only If the linear and angular dimensional tolerances shall not apply, their designation shall be omitted.
Note: For ISO tolerance classes (H, K, L), see table 4 - 7, page 5 - 6.
4.5
Bot h dimensi onal, geometric al and envelope requirements In cases cases where where the envelope requirement requirement also applies to all all single single features of size, size, the designation –E designation –E shall be added after the ISO tolerance class (AC-STD 4555 K). Note: For the purpose of this part of AC-STD 1350 K a single feature of size comprises a cy lindrical surface or two parallel plane surfaces. The envelope requirement ca cannot apply to featur es with individually indicated strai ghtness tolerances, which are greater than their size tolerances, e.g. raw materials.
Group Standards Department ©
STANDARD
en 1350 K
Date
Edition
Page
10
18 (19)
2008-08-22
5
OLDER DRAWING INDICATIONS Older general tolerances and their meaning are explained below.
5.1
Linear measures Permissible deviations Nominal sizes
5.2
Tolerance class 1
2
3
4
-
3
± 0,05
± 0,1
-
-
(3) -
6
± 0,05
± 0,1
± 0,2
± 0,5
(6) -
30
± 0,1
± 0,2
± 0,5
±1
(30) -
120
± 0,15
± 0,3
± 0,8
± 1,5
(120) -
315
± 0,2
± 0,5
± 1,2
±2
(315) -
1000
± 0,3
± 0,8
±2
±3
(1000) -
2000
± 0,5
± 1,2
±3
±4
(2000) -
4000
± 0,8
±2
±4
±6
(4000) -
8000
-
±3
±5
±8
(8000) -
12000
-
±4
±6
± 10
(12000) -
16000
-
±5
±7
± 12
(16000) -
20000
-
±6
±8
± 12
Roundi ng-off radii and chamfers Permissible deviations Nominal sizes
5.3 5.3
Tolerance class 1 and 2
3 and 4
-
3
± 0,2
± 0,4
(3) -
6
± 0,5
±1
(6) -
30
±1
±2
(30) -
120
±2
±4
(120) -
315
±4
±8
Angular dimensions Nominal sizes (shortest side of the angle) L
Permissible deviations Tolerance class 1, 2 and 3 Δα
A
4 *)
Δα
A
*)
-
10
± 1⁰
± 1,75
± 3⁰
± 5,25
(10) -
50
± 30'
± 0,9
± 2⁰
± 3,5
(50) -
120
± 20'
± 0,6
± 1⁰
± 1,75
± 10'
± 0,3
± 30'
± 0,9
(120) -
Figure 10.
*)
The values are valid for measuring lengths of 100 mm according to figure 10. For other me asuring lengths, A shall be increased or decreased in proportion to the measuring length.
Group Standards Department ©
STANDARD Date
2008-08-22 5.4 5.4
Old methods of indication
5.4.1
One tolerance class
5.4.2
Different tolerance classes
en 1350 K Edition
Page
10
19 (19)
