Of all standards, product specification and dimensional standards are most important for maintenance engineers as they give specification and dimensional requirements. To illustrate information given in such standards, information useful to maintenance engineers from IS 1364, part 2 (ISO 4017) and IS 1364, part 3 (ISO 4032) is given in this article. For information on other IS standards and their equivalent ISO, ANSI, BS and DIN standards, please refer article on standards for threaded fasteners.
As information is given only as an illustration, it is not complete and you are requested to refer the standard for full information.
IS 1364, Part 2 (identical to ISO 4017) - Screws/Bolts
IS 1364, part 2 is about hexagon head screws of product grades A and B. From maintenance point of view the most important information is as under.
Product Specification
The standard gives specification and reference standards for the product as under.
| Material | Steel | Stainless steel - Non-ferrous metals | |
| General requirements | International Standard | ISO 8992 | |
| Thread | Tolerance | 6g | |
| International Standards | ISO 261, ISO 965-2 | ||
| Mechanical Properties | Property Class | d < 3 mm, as agreed 3 mm < d < 39 mm, 5.6, 8.8, 10.9 d > 39 mm as agreed |
d < 20 mm, A2-70 20 mm < d < 39 mm, A2-50 d > 39 mm, as agreed |
| International Standards | d < 39 mm, ISO 898-1 d < 3 mm and d > 39 mm as agreed |
d < 39 mm, ISO 3506 – ISO 8839 d > 39 mm as agreed |
|
| Tolerances | Product grade | For d < 24 mm and l < 10 d or 150 mm, A For d > 24 mm and l > 10 d or 150 mm, B |
|
| International Standard | ISO 4759-1 | ||
| Finish and/or coating | As processed plain - plain Requirement for electroplating are covered in ISO 4042. If different electroplating requirements are desired or if requirements are needed for other finishes, they should be agreed between customer and supplier. Limits for surface discontinuities are covered in ISO 6157-1 and ISO 6157-3. |
||
| Acceptability | For acceptance procedure, see ISO 3269 | ||
Please note following things in above table.
- Thread tolerance is defined for the product by the standard.
- Class 4.6 and 4.8 steel are not used for making fasteners unless agreed.
- Product grade is based on size of product.
Product Dimensions
The standard gives following information on dimensions.
- Dimensions for the product (e.g. nominal width across flats and its minimum size) and
- Table showing range of length of fasteners made for a given size (nominal diameter).
Note:
Product information (dimensions) for ISO 4017 is the same as that covered by ISO 4014 with the exception of threading up to the head and nominal length up to and including 200 mm as popular lengths.
In view of above, to illustrate dimensions given by the standard, dimensions given by ISO 4014 (Hexagon head bolts – Product grades A and B) for fasteners up to size M36 is given here. ISO 4014 gives information on thread length (b) in addition to information given in ISO 4017.
ISO 4014-1979
This international standard gives specifications for partly threaded hexagon head bolts with metric dimensions and thread diameters from 3 mm up to and including 36 mm with product grade A for sizes M 3 to M 24 and with product grade B for sizes M 30 and M 36.
| NOM. THREAD DIAMETER (d) | M 3 | M 4 | M 5 | M 6 | M 8 | M 10 | M 12 | |
|---|---|---|---|---|---|---|---|---|
| THREAD PITCH (coarse) | 0.5 | 0.7 | 0.8 | 1 | 1.25 | 1.5 | 1.75 | |
| Thread length (b) for Nom. length (l) | 125 mm & shorter | 12 | 14 | 16 | 18 | 22 | 26 | 30 |
| 125 – 200 mm | - | - | - | - | 28 | 32 | 36 | |
| 200 mm & longer | - | - | - | - | - | - | - | |
| ds | max. | 3 | 4 | 5 | 6 | 8 | 10 | 12 |
| min. | 2.86 | 3.82 | 4.82 | 5.82 | 7.78 | 9.78 | 11.73 | |
| K Nom. Dimensions | 2 | 2.8 | 3.5 | 4 | 5.3 | 6.4 | 7.5 | |
| s | max. | 5.5 | 7 | 8 | 10 | 13 | 16 | 18 |
| min. | 5.32 | 6.78 | 7.78 | 9.78 | 12.73 | 15.73 | 17.73 | |
| NOM. THREAD DIAMETER (d) | (M 14) | M 16 | M 20 | M 24 | M 30 | M 36 | |
|---|---|---|---|---|---|---|---|
| THREAD PITCH (coarse) | 2 | 2 | 2.5 | 3 | 3.5 | 4 | |
| Thread length (b) for Nom. length (l) | 125 mm & shorter | 34 | 38 | 46 | 54 | 66 | 78 |
| 125 – 200 mm | 40 | 44 | 52 | 60 | 72 | 84 | |
| 200 mm & longer | - | 57 | 65 | 73 | 85 | 97 | |
| ds | max. | 14 | 16 | 20 | 24 | 30 | 36 |
| min. | 13.73 | 15.73 | 19.67 | 23.67 | 29.67 | 35.61 | |
| K Nom. Dimensions | 8.8 | 10 | 12.5 | 15 | 18.7 | 22.5 | |
| s | max. | 21 | 24 | 30 | 36 | 46 | 55 |
| min. | 20.67 | 23.67 | 29.67 | 35.38 | 45 | 53.8 | |
For information on range of length of fasteners, please refer the standard.
Method of Designation
The standard has given example to designate a product as under.
Using information given in the standard, a hexagon head screw with thread size M12, nominal length equal to 80 mm and property class 8.8 can be designated / specified as under for its procurement.
Hexagon head screw ISO 4017 – M12 x 80 – 8.8 (as per ISO standard) and
Hexagon head screw IS 1364 (part 2) – ISO 4017 – M12 x 80 – 8.8 (as per IS standard).
Please note that when you designate a product using a standard, it takes care of many things. For example, in above case it takes care of general requirement as per ISO 8992, type of thread (as per ISO 261, ISO 965-2), thread tolerance (6g in this case), mechanical properties (as per ISO standard 898-1), product grade as per ISO 4759-1, surface finish, limits for surface discontinuities (as per ISO 6157-1 and ISO 6157-3) and acceptability as per ISO 3269. It also takes care of various dimensions of screw.
Note:
In ISO standard comma (,) is used as a decimal marker while in Indian Standard the current practice is to use point (.) as the decimal marker.
IS 1364, Part 3 (identical to ISO 4032) – Nuts
IS 1364, Part 3 : Hexagon Nuts, Style 1 (Size Range M 1.6 to M 64) – is identical with ISO 4032.
IS standard 1363 Part 3, 1364 Parts 3 to 6 and 13722 to 13724 are on coarse and fine threaded nuts (equivalent ISO standard numbers are 4032 to 4036 and 8673 to 8675). As same spanner is to be used for tightening either bolt or nut, width across flats for nuts is same as that for bolt / screw head. However their thickness is different as per nut styles. For general applications style 1 nut are used. Thickness of nut for various styles is as under.
Style 1 – 0.8 d (ISO 4032)
Style 2 – 1.0 d (ISO 4033)and
Thin Nuts – 0.5 d (ISO 4035), where d is nominal diameter of fastener.
Method of Designation
The standard gives example to designate a product. As per ISO 4032, hexagon nut, style 1, with thread M12 and property class 8 is designated as follows:
Hexagon nut ISO 4032 – M12 – 8
Important specifications with reference standards, nut dimensions for preferred threads for style 1 nut as per ISO 4032 and dimensions of nuts as per unified (inch) standard are as under. For full information on style 1 / unified nuts and other types of nuts, please refer relevant standards.
Important specifications with reference standards for style 1 nut as per ISO 4032
| Material | Steel | Stainless steel - Non-ferrous metals | |
| General requirements | International Standard | ISO 8992 | |
| Thread | Tolerance | 6H | |
| International Standards | ISO 724, ISO 965-1 | ||
| Mechanical Properties | Property Class | d < 3 mm, as agreed 3 mm ≤ d ≤ 39 mm, 6, 8, 10 d > 39 mm as agreed |
d ≤ 24 mm, A2-70, A4-70 24 mm < d ≤ 39 mm, A2-50, A4-50 d > 39 mm, as agreed |
| International Standards | 3 mm ≤ d ≤ 39 mm, ISO 898-2 d < 3 mm and d > 39 mm, as agreed |
d ≤ 39 mm, ISO 3506-2 – ISO 8839 d > 39 mm as agreed |
|
| Tolerances | Product grade | For d < 16 mm, A For d > 16 mm, B |
|
| International Standard | ISO 4759-1 | ||
| Finish and/or coating | As processed plain - plain
Requirement for electroplating are covered in ISO 4042. Requirements for nonelectrolytically applied zinc flake coatings are covered in ISO 10683 If different electroplating requirements are desired or if requirements are needed for other finishes, they should be agreed between customer and supplier. Limits for surface discontinuities are covered in ISO 6157-2. |
||
| Acceptability | For acceptance procedure, see ISO 3269 | ||
Nut dimensions for preferred threads as per ISO 4032 (Metric Nut Style 1)
All Dimensions are in millimeters
| Thread (d) | M1.6 | M2 | M2.5 | M3 | M4 | M5 | M6 | M8 | M10 | M12 | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Pa | 0.35 | 0.4 | 0.45 | 0.5 | 0.7 | 0.8 | 1 | 1.25 | 1.5 | 1.75 | |
| c | max. | 0.2 | 0.2 | 0.3 | 0.40 | 0.40 | 0.50 | 0.50 | 0.60 | 0.60 | 0.60 |
| min. | 0.1 | 0.1 | 0.1 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | 0.15 | |
| da | max. | 1.84 | 2.3 | 2.9 | 3.45 | 4.6 | 5.75 | 6.75 | 8.75 | 10.8 | 13 |
| min. | 1.60 | 2.0 | 2.5 | 3.00 | 4.0 | 5.00 | 6.00 | 8.00 | 10.0 | 12 | |
| dw | min. | 2.4 | 3.1 | 4.1 | 4.6 | 5.9 | 6.9 | 8.9 | 11.6 | 14.6 | 16.6 |
| e | min. | 3.41 | 4.32 | 5.45 | 6.01 | 7.66 | 8.79 | 11.05 | 14.38 | 17.77 | 20.03 |
| m | max. | 1.30 | 1.60 | 2.00 | 2.40 | 3.2 | 4.7 | 5.2 | 6.80 | 8.40 | 10.80 |
| min. | 1.05 | 1.35 | 1.75 | 2.15 | 2.9 | 4.4 | 4.9 | 6.44 | 8.04 | 10.37 | |
| mw | min. | 0.8 | 1.1 | 1.4 | 1.7 | 2.3 | 3.5 | 3.9 | 5.2 | 6.4 | 8.3 |
| s | nom. =max. | 3.20 | 4.00 | 5.00 | 5.50 | 7.00 | 8.00 | 10.00 | 13.00 | 16.00 | 18.00 |
| min. | 3.02 | 3.82 | 4.82 | 5.32 | 6.78 | 7.78 | 9.78 | 12.73 | 15.73 | 17.73 | |
| Thread (d) | M16 | M20 | M24 | M30 | M36 | M42 | M48 | M56 | M64 | |
|---|---|---|---|---|---|---|---|---|---|---|
| Pa | 2 | 2.5 | 3 | 3.5 | 4 | 4.5 | 5 | 5.5 | 6 | |
| c | max. | 0.8 | 0.8 | 0.8 | 0.8 | 0.8 | 1.0 | 1.0 | 1.0 | 1.0 |
| min. | 0.2 | 0.2 | 0.2 | 0.2 | 0.2 | 0.3 | 0.3 | 0.3 | 0.3 | |
| da | max. | 17.3 | 21.6 | 25.9 | 32.4 | 38.9 | 45.4 | 51.8 | 60.5 | 69.1 |
| min. | 16.0 | 20.0 | 24.0 | 30.0 | 36.0 | 42.0 | 48.0 | 56.0 | 64.0 | |
| dw | min. | 22.5 | 27.7 | 33.3 | 42.8 | 51.1 | 60 | 69.5 | 78.7 | 88.2 |
| e | min. | 26.75 | 32.95 | 39.55 | 50.85 | 60.79 | 71.3 | 82.6 | 93.56 | 104.86 |
| m | max. | 14.8 | 18.0 | 21.5 | 25.6 | 31.0 | 34.0 | 38.0 | 45.0 | 51.0 |
| min. | 14.1 | 16.9 | 20.2 | 24.3 | 29.4 | 32.4 | 36.4 | 43.4 | 49.1 | |
| mw | min. | 11.3 | 13.5 | 16.2 | 19.4 | 23.5 | 25.9 | 29.1 | 34.7 | 39.3 |
| s | nom. = max. | 24.00 | 30.00 | 36 | 46 | 55.0 | 65.0 | 75.0 | 85.0 | 95.0 |
| min. | 23.67 | 29.16 | 35 | 45 | 53.8 | 63.1 | 73.1 | 82.8 | 92.8 | |
| a P is the pitch of the thread. | ||||||||||
For Ready Reference – Dimensions of hex nuts, hex jam nuts and heavy hex nuts as per Unified (inch) Standard.
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 |
Hex Nuts and Hex Jam Nuts
| Nominal Or Basic Major Dia of Thread |
F | G | H | H1 | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Width Across Flats | Width Across Comers | Thickness Hex Nuts | Thickness Hex Jam Nuts | ||||||||||||||||
| Basic | Max | Min | Max | Min | Basic | Max | Mmin | Basic | Max | Min | |||||||||
|
11/32 3/8 7/16 1/2 |
0.344 0.375 0.438 0.500 |
0.332 0.362 0.428 0.489 |
0.397 0.433 0.505 0.577 |
0.378 0.413 0.488 0.557 |
– – 7/32 17/64 |
0.203 0.203 0.226 0.273 |
0.187 0.187 0.212 0.258 |
– – 5/32 3/16 |
– – 0.164 0.195 |
– – 0.150 0.180 |
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|
9/16 11/16 3/4 7/8 |
0.562 0.688 0.750 0.875 |
0.551 0.675 0.736 0.861 |
0.650 0.794 0.866 1.010 |
0.628 0.768 0.840 0.982 |
21/64 3/8 7/16 31/64 |
0.337 0.385 0.448 0.496 |
0.320 0.365 0.427 0.473 |
7/32 1/4 5/16 5/16 |
0.227 0.260 0.323 0.324 |
0.210 0.240 0.302 0.301 |
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|
15/16 1-1/8 1-5/16 1-1/2 |
0.938 1.125 1.312 1.500 |
0.922 1.088 1.269 1.450 |
1.083 1.299 1.516 1.732 |
1.051 1.240 1.447 1.653 |
35/64 41/64 3/4 55/64 |
0.559 0.665 0.776 0.887 |
0.535 0.617 0.724 0.831 |
3/8 27/64 31/64 35/64 |
0.387 0.446 0.510 0.575 |
0.363 0.398 0.458 0.519 |
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|
1-11/16 1-7/8 2-1/16 2-1/4 |
1.688 1.875 2.062 2.250 |
1.631 1.812 1.994 2.175 |
1.949 2.165 2.382 2.598 |
1.859 2.066 2.273 2.480 |
31/32 1-1/6 1-11/64 1-9/32 |
0.999 1.094 1.206 1.317 |
0.939 1.030 1.138 1.245 |
39/64 23/32 25/32 27/32 |
0.639 0.751 0.815 0.880 |
0.579 0.687 0.747 0.808 |
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|
2-7/16 2-5/8 3 3-3/8 |
2.438 2.625 3.000 3.375 |
2.356 2.538 2.900 3.263 |
2.815 3.031 3.464 3.897 |
2.686 2.893 3.306 3.719 |
1-25/64 1-1/2 1-23/32 1-15/16 |
1.429 1.540 1.763 1.986 |
1.353 1.460 1.675 1.890 |
29/32 31/32 1-3/32 1-7/32 |
0.945 1.009 1.138 1.267 |
0.869 0.929 1.050 1.171 |
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|
3-3/4 4-1/8 4-1/2 |
3.750 4.125 4.500 |
3.625 3.988 4.350 |
4.330 4.763 5.196 |
4.133 4.546 4.959 |
2-5/32 2-3/8 2-19/32 |
2.209 2.431 2.654 |
2.105 2.319 2.534 |
1-11/32 1-15/32 1-19/32 |
1.396 1.525 1.654 |
1.292 1.413 1.534 |
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Heavy Hex Nuts
| Nominal Size or Basic Major Dia. of Thread |
F | G | H | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Width Across Flats | Width Across Corners |
Thickness Heavy Hex Nuts |
||||||||||||||
| Basic | Max. | Min. | Max. | Min. | Basic | Max. | Min. | |||||||||
|
1/2 9/16 11/16 3/4 |
0.500 0.562 0.688 0.750 |
0.488 0.546 0.669 0.728 |
0.577 0.650 0.794 0.866 |
0.556 0.622 0.763 0.830 |
15/64 19/64 23/64 27/64 |
0.250 0.314 0.377 0.441 |
0.218 0.280 0.341 0.403 |
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|
7/8 15/16 1-1/16 1-1/4 |
0.875 0.938 1.062 1.250 |
0.850 0.909 1.031 1.212 |
1.010 1.083 1.227 1.443 |
0.969 1.037 1.175 1.382 |
31/64 35/64 39/64 47/64 |
0.504 0.568 0.631 0.758 |
0.464 0.526 0.587 0.710 |
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|
1-7/16 1-5/8 1-13/16 2 |
1.438 1.625 1.812 2.000 |
1.394 1.575 1.756 1.938 |
1.660 1.876 2.093 2.309 |
1.589 1.796 2.002 2.209 |
55/64 63/64 1-7/64 1-7/32 |
0.885 1.012 1.139 1.251 |
0.833 0.956 1.079 1.187 |
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|
2-3/16 2-3/8 2-9/16 2-3/4 |
2.188 2.375 2.562 2.750 |
2.119 2.300 2.481 2.662 |
2.526 2.742 2.959 3.175 |
2.416 2.622 2.828 3.035 |
1-11/32 1-15/32 1-19/32 1-23/32 |
1.378 1.505 1.632 1.759 |
1.310 1.433 1.556 1.679 |
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|
2-15/16 3-1/8 3-1/2 3-7/8 |
2.938 3.125 3.500 3.875 |
2.844 3.025 3.388 3.750 |
3.392 3.608 4.041 4.474 |
3.242 3.449 3.862 4.275 |
1-27/32 1-31/32 2-13/64 2-29/64 |
1.886 2.013 2.251 2.505 |
1.802 1.925 2.155 2.401 |
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|
4-1/4 4-5/8 5 5-3/8 |
4.250 4.625 5.000 5.375 |
4.112 4.475 4.838 5.200 |
4.907 5.340 5.774 6.207 |
4.688 5.102 5.515 5.928 |
2-45/64 2-61/64 3-3/16 3-7/16 |
2.759 3.013 3.252 3.506 |
2.647 2.893 3.124 3.370 |
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|
5-3/4 6-1/8 |
5.750 6.125 |
5.562 5.925 |
6.640 7.073 |
6.341 6.755 |
3-11/16 3-15/16 |
3.760 4.014 |
3.616 3.862 |
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