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ISO Screw Profile and Tolerance selection

Introduction..... Relevant Standards..... Example.....
Basic Thread Profile..... Profile Dimensions..... Basic Screw Dimensions.....
Screw Pitch..... Tolerance Class Description..... Tolerance Selection.....
Table relating Tol'ce grade to class and length..... Length Parameter.....
Table of Fundamental deviation (EI/es) against pitch.....
Table of Tolerance widths (Pitch Dia's).....
Table of Tolerance widths (Major Dia(Male) and Minor dia (Female).....
Root Contours..... Example in table form.....

Introduction

The notes below are outline in nature and are very much second best to the standards identified.  Quality information is best found in the standards.

The notes on this page identify the basic ISO thread form and illustrate how the tolerances related to the thread form are developed from the simple rules provided in the relevant Standards.  Using the equations and tables available on this page it is possible to obtain the limits for all available dia-pitch-tolerance class combination.

The standard BS 3643 Part 1 relates to single start parallel screw threads of sizes from 1 to 300 mm.   Part 2 provides selected limits of sizes for the rang of screw threads.  

The ISO standards quoted below are very similar the the British standards and provide essentially the same information.   The Standard ISO 965 Part 2 (size range 1-64mm)provides much more limited information compared to BS 3643 Part 2. ( size range 1-300mm ).

A table of ISO form screw threads from 1,6 to 300mm is found on ISO screw threads. This table relates to a medium tolerance grade screw nut combination (6H/6g) which is the grade implied if it is not specified.






Relevant Standards

BS 3643 Part 1:2007..ISO metric screw threads. Principles and basic data

BS 3643 Part 2:2007..ISO metric screw threads. Specification for selected limits of size

BS 3692:2001..ISO metric precision hexagon bolts, screws and nuts. Specification


BS ISO 965-1:1998 ...ISO general purpose metric screw threads. Tolerances (g.p.s.t.T). Principles and basic data

BS ISO 965-2:1998 ...ISO g.p.s.t.T . Limits of sizes for general purpose external and internal screw threads. Medium quality

BS ISO 261:1998 ...ISO general purpose metric screw threads. General plan






Tolerance selection Example

1) Tolerances for a M20 coarse thread medium fit.

The pitch for a M20 coarse thread is 2,5mm....Pitch
For the normal commercial applications a 6H/6g... Tolerance Selection

External Thread

Calculating the limits for the external thread diameter (d)
Fundamental deviation for es (g) = -42 μm.... Fundamental Deviation
The diameter tolerance width for an M20 g6 is 335μm. ....Tolerance Widths
The limits for d is therefore (max = 20 - 0,042 = 19,958 ),(min = 19.958 -0,335 = 19,623 )
Ans(max 19,958, min19,623 )



Calculating the limits for the external thread pitch diameter (d 2)
The basic pitch diameter is 20 - 2*0,32476.P = 18,3762
Fundamental deviation es = -42 μm. ...Fundamental Deviation
The pitch tolerance width (Td2) for an M20 g6 is 170μm..... Tolerance Widths
The limits for d 2 is therefore (max = 18,3762 - 0,042 = 18,334 ),(min = 18.334 -0,170 = 18,164 )
Ans(max 18,334, min 18,164 )



Calculating the limits for the external thread root diameter (d 3)... Root Contours
The basic root diameter d1 is 20 - 2*0,54127.P = 17,294
To obtain the minimum root dia d3min first calculate
z = H/4 + Td2 /2 - P/8 = 0.21651P + 0,170/2 -0,125P = 0,3138
d 3min = d1 - es -2z = 17,294 - 0.042 - 2*0,0,3138 = 16.624

The tables in the standards do not include a table value for d 3max
The table on this website ( Screw Threads ) uses a value d 3max = d1 - es. = 17,252... This is the diameter of the Go-Gauge Profile.
A value more in line with the recommendations in the standards can be found using the equations found on this page Root Contours


(I will update the table in line with these recommendations over time - (R.B. 6/3/2008)


Internal Thread

Calculating the limits for the internal thread Minor diameter (d1)
The basic minor diameter d1 = 20 - 2*0,54127.P = 17,294
Fundamental deviation for EI(H) = 0 μm.... Fundamental Deviation
The diameter tolerance width for an M20 H6 is 450μm. ....Tolerance Widths
The limits for d is therefore (min = 17,294 + 0 = 17,294 ),(max = 17,294 + 0,450 = 17,744 )
Ans(max 17,744, min 17,294 )



Calculating the limits for the internal thread pitch diameter (d 2)
The basic pitch diameter is 20 - 2*0,32476.P = 18,3762
Fundamental deviation EI = 0 μm. ...Fundamental Deviation
The pitch tolerance width (Td2) for an M20 H6 is 224μm..... Tolerance Widths
The limits for d 2 is therefore (min = 18,376 + 0 = 18.376 ),(max = 18.376 + 0,224 = 18,600 )
Ans(max 18,334, min 18,164 )



Calculating the limits for the internal thread major diameter D
The basic Major diameter D is 20
The minimum major dia Dmin = 20,000

The Standards do not include a table value for D max
It also does not seem to give guidance on how to obtain.   They simply state that the thread should not transgress the basic profile.< /p>




Basic Thread Profile to BS 3643






Table of Basic Profile Dimensions

  H 5/8H 3/8H H/4 H/8 H/6
Pitch 0,86603P 0,54127P 0,32476P 0,21651P 0,10825P 0,144337P
mm mm mm mm mm mm mm
0,2 0,17320508 0,10825318 0,0649519 0,04330128 0,02165064 0,02886752
0,25 0,21650635 0,13531648 0,08118988 0,0541266 0,0270633 0,0360844
0,3 0,25980762 0,16237977 0,09742785 0,06495192 0,03247595 0,04330127
0,35 0,30310889 0,18944307 0,11366583 0,07577724 0,03788861 0,05051815
0,4 0,34641016 0,21650636 0,1299038 0,08660256 0,04330127 0,05773503
0,45 0,38971143 0,24356966 0,14614178 0,09742788 0,04871393 0,0649519
0,5 0,4330127 0,27063295 0,16237975 0,1082532 0,05412659 0,07216878
0,6 0,51961524 0,32475954 0,1948557 0,12990384 0,06495191 0,08660253
0,7 0,60621778 0,37888613 0,22733165 0,15155448 0,07577723 0,1010363
0,75 0,64951905 0,40594943 0,24356963 0,1623798 0,08118989 0,10825318
0,8 0,69282032 0,43301272 0,2598076 0,17320512 0,08660254 0,11547005
1 0,8660254 0,5412659 0,3247595 0,2165064 0,10825318 0,14433757
1,25 1,08253175 0,67658238 0,40594938 0,270633 0,13531648 0,18042197
1,5 1,2990381 0,81189885 0,48713925 0,3247596 0,16237977 0,21650635
1,75 1,51554445 0,94721533 0,56832913 0,3788862 0,18944307 0,25259075
2 1,7320508 1,0825318 0,649519 0,4330128 0,21650636 0,28867513
2,5 2,1650635 1,35316475 0,81189875 0,541266 0,27063295 0,36084392
3 2,5980762 1,6237977 0,9742785 0,6495192 0,32475954 0,4330127
3,5 3,0310889 1,89443065 1,13665825 0,7577724 0,37888613 0,50518148
4 3,4641016 2,1650636 1,299038 0,8660256 0,43301272 0,57735027
4,5 3,8971143 2,43569655 1,46141775 0,9742788 0,48713931 0,64951905
5 4,330127 2,7063295 1,6237975 1,082532 0,5412659 0,72168783
5,5 4,7631397 2,97696245 1,78617725 1,1907852 0,59539249 0,79385662
6 5,1961524 3,2475954 1,948557 1,2990384 0,64951908 0,8660254
8 6,9282032 4,3301272 2,598076 1,7320512 0,86602544 1,15470053





Basic Screw Dimensions

From these basic proportions it is very easy to obtain the basic thread dimensions a typical set of ISO metric coarse threads are identified with the basic dimensions as shown below



Table showing dimensions of some typical ISO metric coarse threads

Thread Pitch Major Pitch Dia Minor Thread Pitch Major Pitch Dia Minor
P D/d D2 /d 2 D1 /d 1 P D/d D2 /d 2 D1 /d 1
mm mm mm mm mm mm mm mm
M3 x 0,5 0,5 3,000 2,675 2,459 M12x1,75 1,7 12,000 10,863 10,106
M4 x 0,7 0,7 4,000 3,545 3,242 M16 x 2,0 2 16,000 14,701 13,835
M5 x 0,8 0,8 5,000 4,48 4,134 M20 x2,5 2,5 20,000 18,376 17,294
M6 x 1,0 1 6,000 5,35 4,917 M24 x 3,0 3 24,000 22,051 20,752
M8 x 1,25 1,25 8,000 7,188 6,647 M30 x 3,5 3,5 30,000 27,727 26,211
M10 x 1,5 1,5 10,000 9,026 8,376 M36 x 4,0 4 36,000 33,402 31,67





Screw Pitch

There are a number of pitch values for each screw diameter.   The selection as to the pitch is based on the application.  The largest pitch option for diameters M1 to M64 is identified as the coarse pitch and is to one used for general engineering applications.  A table of the coarse pitch series is provided below.   Other pitch values for each diameter are called the fine series or constant series.

M1 x 0,25 M1,2 x 0,25M1,4 x 0,30M1,6 x 0,35 M1,8 x 0,35M2 x 0,4M2,2 x 0,45
M2,5 x 0,45M2,5 x 0,45M3 x 0,5M3,5 x 0,6 M4 x 0,7M4,5 x 0,75M5 x 0,8
M6 x 1M7 x 1M8 x1,25M9 x1,25 M10 x 1,5M11 x 1,5M12 x 1,75
M14 x 2,0M16 x 2M18 x 2,5M20 x 2,5 M22 x 2,5 M24 x 3,0 M27 x 3
M30 x 3,5 M33 x 3,5 M36 x 4 M39 x 4 M42 x 4,5 M45 x 5M48 x5
M52 x 5M56 x5,5 M60 x 5,5 M64 x 6M68 x 6

Fine series threads are only listed in the standards up to M33.   The name fine does not imply higher quality.  The fine series are listed below.

M1 / M1,1/ M1,2 / M1,4 / M1,6 / M1,8 (x 0,2) M2 / M2,2 (x 0,25)M2,5 / M3 / M3,5 (x 0,35)
M4 / M4,5 / M5,5 (x 0,5)M6 / M7( x 0,75)M8 x 1
M10 / 12 (x 1,25)M14 / M16 / M18 / M20 / M22 (x 1,5) M24 / M25 / M27/ M30 / M33 (x 2)

The constant thread series are identified in the standards for the screw range M8 upwards and are normally those pitches not classed as coarse or fine






Tolerances for External (screws) and Internal (Nuts) Threads

The method of applying manufacturing tolerances to the female and male threads such that they fit together is by use of the tolerance class which is a combination of the tolerance grade ( a number) and a tolerance position ( a letter).    For the female threads the letter is upper class and for the male threads the letter is lower class.   Therefore H6 is a tolerance grade for a female ( Internal ) thread and g6 is a tolerance grade for a male (External ) thread.

The tolerance band positions relative to the basic zero size are illustrated in the figure below

The (fundamental)tolerance position is defined as the nearest end of the tolerance band to the zero tolerance position (Dead size position).  These positions are identified as EI for the female thread and es for the male thread.

There are a limited number of tolerance grades used to specify threads and the standards identify these grades for the Minor ( D1 ) and Pitch ( D2 )diameters of the female threads and the Major ( d ) and Pitch ( d2 ) diameters of the male threads.   Tolerance grades are not provided for none critical female major dia (D) and the male minor diameter (d3).  The numbers of grades used are listed below.


D1 : tolerance grades 4,5,6,7 & 8
d : tolerance grades 4,6, & 8
D2 tolerance grades 4,5,6,7 & 8
d2 tolerance grades 3,4,5,6,8 & 9

The tolerance positions available are EI = G & H for female threads and es = e,f g, or h for male threads.






Selection of tolerance classes

To simplify the selection of the tolerance classes threads have been divide into three categories.

Fine ... For precision threads
Medium ...For general industrial use
Coarse .. For rough manufacture threads


The length of thread engagement is also used as a parameter for selection of the tolerance class

The following tables identifies the range of tolerance classes and the length of screws for selecting the length parameter.






Table showing tolerance classes

Female Threads
Class
v
Tolerance Position GTolerance Position H
Short NormalLongShortNormallong
Fine -- - 4H 5H 6H
Medium 5G6G 7G 5H 6H 7H
Rough -7G 8G - 7H 8H


Male Threads
Class
v
Tolerance Position e Tolerance Position f Tolerance Position gTolerance Position h
Short NormalLong ShortNormalLong Short NormalLongShort NormalLong
Fine                 3h4h 4h 5h4h
Medium  6e 7e6e   6f    5g6g 6g 7g6g 5h6h 6h 7h6h
Rough         8g9g8g   

....First Choice
....Second Choice
... Commercial Nuts /Bolt Threads
... Third choice to be avoided

Note:
When two shaft tolerance grades are shown the first is for the pitch dia and the second is for the major diameter.
When only one is shown it is the same for both diameters.






Table For Selecting Screw Length Parameter

Basic Major Dia Pitch Length of Thread Engagement
Short Normal Long
over Up to +(inc) Up to + (Inc) Over Up to + (Inc) Over
mm mm mm mm mm mm mm
0,99 1,4 0,2 0,5 0,5 1,4 1,4
0,25 0,6 0,6 1,7 1,7
0,3 0,7 0,7 2,0 2,0
1,4 2,8 0,2 0,5 0,5 1,5 1,5
0,25 0,6 0,6 1,9 1,9
0,35 0,8 0,8 2,6 2,6
0,4 1,0 1,0 3,0 3,0
0,45 1,3 1,3 3,8 3,8
2,8 5,6 0,35 1,0 1,0 3,0 3,0
0,5 1,5 1,5 4,5 4,5
0,6 1,7 1,7 5,0 5,0
0,7 2 2 6 6
0,75 2,2 2,2 6,7 6,7
0,8 2,5 2,5 7,5 7,5
5,6 11,2 0,75 2,4 2,4 7,1 7,1
1,0 3 3 9 9
1,25 4 4 12 12
1,5 5 5 15 15
11,2 22,4 1,0 3,8 3,8 11 11
1,25 4,5 4,5 13 13
1,5 5,6 5,6 16 16
1,75 6 6 18 18
2,0 8 8 24 24
2,5 10 10 30 30
22,4 45,0 1,0 4 4 12 12
1,5 6,3 6,3 19 19
2,0 8,5 8,5 25 25
3,0 12 12 36 36
3,5 15 15 45 45
4,0 18 18 53 53
4,5 21 21 63 63
45,0 90,0 1,5 7,5 7,5 22 22
2,0 9,5 9,5 28 28
3,0 15 15 45 45
4,0 19 19 56 56
5,0 24 24 71 71
5,5 28 28 85 85
6,0 32 32 95 95
90,0 180,0 2,0 12 12 36 36
3,0 18 18 53 53
4,0 24 24 71 71
6,0 36 36 106 106
180,0 300 3,0 20 20 60 60
4,0 26 26 80 80
5,0 40 40 118 118





Table relating Fundamental deviation EI and es to Pitch

Pitch Female Thread D2,D1 Male Thread d,d2 Pitch Female Thread D2,D1 Male Thread d,d2
EI es EI es
G H e f g h G H e f g h
mm μm μm μm μm μm μm mm μm μm μm μm μm μm
0,2 +17 0 - - -17 0 1,25 +28 0 -63 -42 -28 0
0,25 +18 0 - - -18 0 1,5 +32 0 -67 -45 -32 0
0,3 +18 0 - - -18 0 1,75 +34 0 -71 -48 -34 0
0,35 +19 0 - -34 -19 0 2,0 +38 0 -71 -52 -38 0
0,4 +19 0 - -34 -19 0 2,5 +42 0 -80 -58 -42 0
0,45 +20 0 - -35 -20 0 3,0 +48 0 -85 -63 -48 0
0,5 +20 0 -50 -36 -20 0 3,5 +53 0 -90 -70 -53 0
0,6 +21 0 -53 -36 -21 0 4,0 +60 0 -95 -75 -60 0
0,7 +22 0 -56 -38 -22 0 4,5 +63 0 -100 -80 -63 0
0,75 +22 0 -56 -38 -22 0 5,0 +71 0 -106 -85 -71 0
0,8 +24 0 -60 -38 -24 0 5,5 +75 0 -112 -90 -75 0
1,0 +26 0 -60 -40 -26 0 6,0 +80 0 -118 -95 -80 0
              8,0 +100 0 -140 -118 -100 0





Table of T tolerance widths. (Pitch Diameters )
For Finished uncoated threads.

D2 /d2 Pitch Pitch Diameter of internal threads Pitch diameter of external threads
Over To(&inc) T:4 T:5 T:6 T:7 T:8 T:3 T:4 T:5 T:6 T:7 T:8 T:9
mm mm mm μm μm μm μm μm μm μm μm μm μm μm μm
0,99 1,4 0,2 40 - -     24 30 48 48      
    0,25 45 56 -     25 34 42 53      
    0,3 48 60 75     28 36 45 56      
1,4 2,8 0,2 42         25 32 40 50      
    0,25 48 60       28 36 45 56      
    0,35 53 67 85     32 40 50 63 80    
    0,4 56 71 90     34 42 53 67 85    
    0,45 60 75 95     36 45 56 71 90    
2,8 5,6 0,35 56 71 90     34 52 53 67 85    
    0,5 63 80 100 125   38 48 60 75 95    
    0,6 71 90 112 140   42 53 67 85 106    
    0,7 75 95 118 150   45 56 71 90 112    
    0,75 75 95 118 150   45 56 71 90 112    
    0,8 80 100 125 160 200 48 60 75 95 118 150 90
5.6 11,2 0,75 85 106 132 170   50 63 80 100 125    
    1 95 118 140 190 236 56 71 90 112 140 180 224
    1,25 100 125 160 200 250 60 75 95 118 150 189 235
    1,5 112 140 180 224 280 67 85 106 132 170 212 265
11,2 22,4 1 100 125 160 200 250 60 75 95 118 150 190 235
    1,25 112 140 180 224 280 67 85 106 132 170 212 265
    1,4 118 150 190 236 300 71 90 112 140 180 224 280
    1,75 125 160 200 250 315 75 95 118 150 190 236 300
    2,0 132 170 212 265 335 80 100 125 160 200 250 315
    2,5 140 180 224 280 355 85 106 132 170 212 265 335
22,4 45 1 106 132 170 212   63 80 100 125 160 200 250
    1,5 125 160 200 250 315 75 95 118 150 190 236 300
    2 140 180 224 280 355 85 106 132 170 212 265 335
    3 170 212 265 335 425 100 125 160 200 250 315 400
    3,5 180 224 280 355 450 106 132 170 212 265 335 425
    4 190 236 300 375 475 112 140 180 224 280 355 450
    4,5 200 250 315 400 500 118 150 190 236 300 375 475
45 90 1,5 132 170 212 265 335 80 100 125 160 200 250 315
    2 150 190 236 300 375 90 112 140 180 224 280 355
    3 180 224 280 355 450 106 132 170 212 265 335 425
    4 200 250 315 400 500 118 150 190 236 300 375 475
    5 212 265 335 425 530 125 160 200 250 315 400 500
    5,5 224 280 355 450 560 132 170 212 265 335 425 530
    6 236 300 375 475 600 140 180 224 280 355 450 560
90 180 2 160 200 250 315 400 95 118 150 190 236 300 375
    3 190 236 300 375 475 112 140 180 224 280 355 450
    4 212 265 335 425 530 125 160 200 250 315 400 500
    6 250 315 400 500 630 150 190 236 300 375 475 600
    8 280 355 450 560 710 175 212 265 335 425 530 670
180 355 3 212 265 335 425 530 125 160 200 250 315 400 500
    4 236 300 375 475 60 140 180 224 280 355 450 560
    6 265 335 425 530 670 160 200 250 315 400 500 630
    8 300 375 475 600 750 180 224 280 355 450 560 710
Over To(&inc) Pitch μm μm μm μm μm μm μm μm μm μm μm μm
D2 /d2 T:4 T:5 T:6 T:7 T:8 T:3 T:4 T:5 T:6 T:7 T:8 T:9
Pitch Diameter of internal threads Pitch diameter of external threads





Table of T tolerance widths. (Major (Male) and Minor Diameters (Female)
For Finished uncoated threads.

Pitch Major Dia -Male threads Minor Diameter - Female Threads
T:4 T:6 T:8 T:4 T:5 T:6 T:7 T:8
mm μm μm μm μm μm μm μm; μm
0,2 36 56   38        
0,25 42 67   45 56      
0,3 48 75   53 67 85    
0,35 53 85   63 80 100    
0,4 60 95   71 90 112    
0,45 63 100   80 100 125    
0,5 67 106   90 112 140 180  
0,6 80 125   100 125 160 200  
0,7 90 140   112 140 180 224  
0,75 90 140   118 150 190 236  
0,8 95 150 236 125 160 200 250 315
1,0 112 180 280 150 190 236 300 375
1,25 132 212 335 170 212 265 335 425
1,5 150 236 375 190 236 300 375 475
1,75 170 265 425 212 236 335 425 530
2,0 180 280 450 236 300 375 475 600
2,5 212 335 530 280 355 450 560 710
3,0 236 375 600 315 400 500 630 800
3,5 265 425 670 355 450 560 710 900
4,0 300 475 750 375 475 600 750 950
4,5 315 500 800 425 530 670 850 1060
5,0 335 530 850 450 560 710 900 1120
5,5 355 560 900 475 600 750 950 1180
6,0 375 600 950 500 630 800 1000 1250
8,0 450 710 1180 630 800 1000 1250 1600
mm μm μm μm μm μm μm μm; μm
Pitch T:4 T:6 T:8 T:4 T:5 T:6 T:7 T:8
Major Dia -Male threads Minor Diameter - Female Threads





Root Contours

For both internal and external threads the actual root contours shall not transgress the basic profile.

Note: In accordance with the requirements of BS EN ISO 898-1 for external fasteners of property class 8,8 and higher the root profile shall have non-reversing curvature, no part of the profile shall have a radius of less than 0,125P.  It is advisable to attempt a truncation of C = H/6 as a basis for stress calculation of the minor dia d3

In the maximum minor position d 3min the two radii of Rmin = 0,125P will go through the corners of the no-go gauge profile and blend with the flanks of the maximum metal condition thread form.(see figure below)

The maximum truncation Cmaxis calculated using the following equation

Cmin = 0,125P

To calculate d3min first obtain z

d3min = d1 - es -2z

To calculate d3max first obtain y

d3max = d1 - es - 2y






Examples
Male Threads

Name Equation Identity Values
Designation     M30 x 3,5 - 6g M12 x 1,25 -4h M150 x 4 - 6e M200 x 6 - 4g
Diameter d d 30 12 150 200
Pitch P P 3,5 1,25 4 6
Basic Pitch Dia d2 =d-0,68952P d2 27,727 11,188 147,402 196,103
Basic Minor Dia d1=d-1,08254,P d1 26,211 10,647 145,67 193,505
Fundamental Deviation es es 0,053 0 0,095 0,08
Tolerance Width diameter (d) Td Td 0,425 0,132 0,375 0,6
Tolerance Width Pitch dia,d 2 Td2 Td2 0,212 0,085 0,19 0,315
Extreme Deviation d eid = es+Td eid 0,478 0,132 0,47 0,68
Extreme Deviation d 2 eid2 = es+Td2 eid2 0,265 0,085 0,085 0,085
Rmin Rmin = 0,125P Rmin 0,438 0,156 0,5 0,75
z See above   0,426 0,157 0,461 0,707
y See above   0,064 0,021 0,09 0,125
             
Major Dia (max) dmin = d + es dmin 29,947 12 149,905 199,92
Major Dia (max) dmax=d+ eid dmax 29,522 11,868 149,53 199,32
Pitch Dia (max) d2min = d2+es d2min 27,674 11,188 147,307 196,023
Pitch Dia (min) d2max=d2+eid2 d2max 27,462 11,103 147,317 196,018
Minor Dia (min) d3min =d1-es-2z d3min 25,306 10,333 144,653 192,012
Minor Dia (max) d3max = d1-es-2y d3max 26,029 10,606 145,396 193,175


Female Threads

Name Equation Identity Values
      M30 x 3,5 -6H M12 x1,25 - 7H M150 x 4 - 6G M200 x 6 x 5H
Diameter D D 30 12 150 200
Pitch P P 3,5 1,25 4 6
Basic Pitch Dia D2 = D-0,68952P D2 27,727 11,188 147,402 196,103
Basic Minor Diameter D1=D-1,08254,P D1 26,211 10,647 145,67 193,505
Fundamental Deviation EI EI 0 0 0,06 0
Tolerance Width diameter (d) T T 0 0 0 0
Tolerance Width Pitch diameter (D2) TD2 TD2 0,28 0,224 0,335 0,335
Tolerance Width Minor Dia(D1) TD1 TD1 0,56 0,335 0,6 0,63
Extreme Deviation (D2) ESD2 = EI+TD2 ESD2 0,28 0,224 0,395 0,335
Extreme Deviation (D1) ESD1 = EI+TD1/ ESD1 0,56 0,335 0,66 0,63
             
Major Di (min) Dmin Dmin 30 12 150 200
Pitch Dia (min) D2min = D2+EI D2min 27,727 11,188 147,462 196,103
Pitch Dia (max) D2max=D2+ ESD2 D2max 28,007 11,412 147,797 196,438
Minor Dia (min) D1min = D1+EI D1min 26,211 10,647 145,73 193,505
Minor Dia (max) D1max=D1+ ESD1 D1max 26,771 10,982 146,33 194,135

Useful Links
  1. Metric Thread Sizes..Metric THREAD sizes from Tribology - abc
  2. Metric Thread Sizes..Metric THREAD sizes from Newmantools - abc
  3. Metric Thread Tolerances..Metric Thread tolerances from Fullermetric
  4. Metrication.com..Information on metric threads and other metric subjects
  5. Maryland Metrics..Comprehensive information on metric screws threads.

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Last Updated 21/01/2015