ISO 4672 Hexagon Socket Head Cap Screws (Metric)

Equivalent Standards

ISO 4762 International Standard specifies the characteristics of hexagon socket head cap screws with threads from Ml.6 up to and including M64 and product grade A.
If, in special cases, specifications other than those listed in this International Standard are required, they should be selected from existing International Standards, for example ISO 261, ISO 888, ISO 898-1, ISO 965-2, ISO 3506-1 and ISO 4759-1.

Dimensions

Symbol and designation of symbols are defined in ISO 225

Symbol and designation of symbols are defined in ISO 225

DIN 3570 U Bolts

Permissible alternative form of socket

DIN 3570 U Bolts

Top and botton edge of the head

1) A slight rounding or countersink at the mouth of the socket is permissible.
2) Point chamfered or for sizes M4 and below “as rolled”, see ISO 4753.
3) lncomplete thread u ≤ 2 P.
4)ds applies if value of lsmin are specified.
5)Top edge of head may be rounded or chamfered as shown at the discretion of the manufacturer.
6)Bottom edge of head may be rounded or chamfered to dw but in every case must be free from burrs.

Thread (d) p1) b2) dk da ds e lf k r s t v dw w
ref max3 max4 min max max min min5 max max min min nom max6 max7 min min max min min
M1.6 0.35 15 3.00 3.14 2.86 2 1.60 1.46 1.73 0.34 1.60 1.46 0.1 1.5 1.545 1.560 1.520 0.7 0.16 2.72 0.55
2 0.4 16 3.80 3.98 3.62 2.6 2.00 1.86 1.73 0.51 2.00 1.86 0.1 1.5 1.545 1.560 1.520 1 0.2 3.48 0.55
2.5 0.45 17 4.50 4.68 4.32 3.1 2.50 2.36 2.3 0.51 2.50 2.36 0.1 2 2.045 2.060 2.020 1.1 0.25 4.18 0.85
M3 0.5 18 5.50 5.68 5.32 3.6 3.00 2.86 2.87 0.51 3.00 2.86 0.1 2.5 2.56 2.58 2.52 1.3 0.3 5.07 1.15
M4 0.7 20 7.00 7.22 6.78 4.7 4.00 3.82 3.44 0.6 4.00 3.82 0.2 3 3.071 3.080 3.020 2 0.4 6.53 1.4
M5 0.8 22 8.50 8.72 8.28 5.7 5.00 4.82 4.58 0.6 5.00 4.82 0.2 4 4.084 4.095 4.020 2.5 0.5 8.03 1.9
M6 1 24 10.00 10.22 9.78 6.8 6.00 5.82 5.72 0.68 6.0 5.7 0.25 5 5.084 5.140 5.020 3 0.6 9.38 2.3
M8 1.25 28 13.00 13.27 12.73 9.2 8.00 7.78 6.86 1.02 8.00 7.64 0.4 6 6.095 6.140 6.020 4 0.8 12.33 3.3
M10 1.5 32 16.00 16.27 15.73 11.2 10.00 9.78 9.15 1.02 10.00 9.64 0.4 8 8.115 8.175 8.025 5 1 15.33 4
M12 1.75 36 18.00 18.27 17.73 13.7 12.00 11.73 11.43 1.45 12.00 11.57 0.6 10 10.115 10.175 10.025 6 1.2 17.23 4.8
(M14)8 2 40 21.00 21.33 20.67 15.7 14.00 13.73 13.72 1.45 14.00 13.57 0.6 12 12.142 12.212 12.032 7 1.4 20.17 5.8
M16 2 44 24.00 24.33 23.67 17.7 16.00 15.73 16 1.45 16.00 15.57 0.6 14 14.142 14.212 14.032 8 1.6 23.17 6.8
M20 2.5 52 30.00 30.33 29.67 22.4 20.00 19.67 19.44 2.04 20.00 19.48 0.8 17 17.23 17.05 10 2 28.87 8.6
M24 3 60 36.00 36.39 35.61 26.4 24.00 23.67 21.73 2.04 24.00 23.48 0.8 19 19.275 19.065 12 2.4 34.81 10.4
M30 3.5 72 45.00 45.39 44.61 33.4 30.00 29.67 25.15 2.89 30.00 29.48 1 22 22.275 22.065 15.5 3 43.61 13.1
M36 4 84 54.00 54.46 53.54 39.4 36.00 35.61 30.85 2.89 36.00 35.38 1 27 27.275 27.065 19 3.6 52.54 15.3
M42 4.5 96 63.00 63.46 62.54 45.6 42.00 41.61 36.57 3.06 42.00 41.38 1.2 32 32.33 32.08 24 4.2 61.34 16.3
M48 5 108 72.00 72.46 71.54 52.6 48.00 47.61 41.13 3.91 48.00 47.38 1.6 36 36.33 36.08 28 4.8 70.34 17.5
M56 5.5 124 84.00 84.54 83.46 63 56.00 55.54 46.83 5.95 56.00 55.26 2 41 41.33 41.08 34 5.6 82.26 19
M64 6 140 96.00 96.54 96.46 71 64.00 63.54 52.53 5.95 64.00 63.26 2 46 46.33 46.08 38 6.4 94.26 22

1. p is the pitch of the thread.
2. For lengths below the thick dashed line.
3. For Plain heads.
4. For knurled heads. 5. emin = 1.14 s min 6. For Property class 12.9
7. For all other property classes.
8. The size in brackets shoulde be avoided if possible.

l9 Shank length ls and grip Length ls
Thread (d) ls lg ls lg ls lg ls lg ls lg ls lg ls lg ls lg
nom. min. max. min. max. min. max. min. max. min. max. min. max. min. max. min. max. min. max.
M2.5 2.3 2.7
M3 2.8 3.2
M4 3.76 4.24
M5 4.76 5.24
M6 5.76 6.24
M8 7.71 8.29
M10 9.71 10.29
M12 11.65 12.35
M16 15.65 16.35
M20 19.58 20.42 2 4
M25 24.58 25.42 5.75 8 4.5 7
M30 29.58 30.42 9.5 12 6.5 10 4 8
M35 34.5 35.5 11.5 15 9 13 6 11
M40 39.5 40.5 16.5 20 14 18 11 16 5.75 12
M45 44.5 45.5 5.5 13 19 23 16 21 10.75 17
M50 49.5 50.5 10.5 18 24 28 21 26 15.75 22
M55 54.4 55.6 15.5 23 10.25 19 26 31 20.75 27
M60 59.4 60.6 20.5 28 15.25 24 10 20 31 36 25.75 32
M65 64.4 65.6 25.5 33 20.25 29 15 25 11 21 30.75 37
M70 69.4 70.6 30.5 38 25.25 34 20 30 16 26 35.75 42
M80 79.4 80.6 40.5 48 35.25 44 30 40 26 36 15.5 28 45.75 52
M90 89.3 90.7 50.5 58 45.25 54 40 50 36 46 25.5 38 15 30
M100 99.3 100.7 60.5 68 55.25 64 50 60 46 56 35.5 48 25 40
M110 109.3 110.7 65.25 74 60 70 56 66 45.5 58 35 50 20.5 38
M120 119.3 120.7 75.25 84 70 80 66 76 55.5 68 45 60 30.5 48 16 36
M130 129.2 130.8 80 90 76 86 65.5 78 55 70 40.5 58 26 46
M140 139.2 140.8 21.5 44 90 100 86 96 75.5 88 65 80 50.5 68 36 56
M150 149.2 150.8 31.5 54 96 106 85.5 98 75 90 60.5 78 46 66
M160 159.2 160.8 41.5 64 27 52 106 116 95.5 108 85 100 70.5 88 56 76
M180 179.2 180.8 61.5 84 47 72 28.5 56 115.5 128 105 120 90.5 108 76 96
M200 199.075 200.925 81.5 104 67 92 48.5 76 30 60 135.5 148 125 140 110.5 128 96 116
M220 219.075 220.925 101.5 124 87 112 68.5 96 50 80
M240 239.075 240.925 121.5 144 107 132 88.5 116 70 100
M260 258.95 261.05 141.5 164 127 152 108.5 136 90 120
M280 278.95 281.05 161.5 184 147 172 128.5 156 110 140
M300 298.95 301.05 181.5 204 167 192 148.5 176 130 160

9. The range of commercial length is between the thick stepped lines. Length above the dashed stepped line are threaded to the head within 3 p. Lenght below the dashed stepped lines have values of lg and ls in accordance with the following formulae:
lg max = l nom - b
ls = l g max - 5 p.

Requirements and reference International Standards

Material Steel Stainless Steel Non-ferrous metal
General requirements International Standard ISO 8992
Thread Tolerance 5g6g for property class 12.9; for other property classes: 6g
International Standards ISO 261 , ISO 965-2 , ISO 965-3
Mechanical Properties Property class < M3: as agreed
≥ M3 and ≤ M39:
8.8, 10.9, 12.9
> M39: as agreed 		≤ M24:
A2-50, A2-702)
>M24 and ≤ M39:
A2-50, A4-50
2)
> M39: as agreed		 all defined materials
International Standards ISO 898-11) ISO 3506-1 ISO 8839
Tolerance Product grade A
International Standards ISO 4759-1
Finish Black oxide
(thermal or chemical)		 Plain Plain

Requirements for electroplating are covered in ISO 4042

 --

Requirements for electroplating are covered in ISO 4042

If different electroplsting requirements are dsired or if requirements are needed for other finishes, they shall be agreeed between customer and supplier.

Limits for surface discontinuous are cover in ISO 6157-1 and ISO 6157-3
Acceptability Acceptance procedure is covered in ISO 3269

1) For Screws unsuitable for tensile testing, the hardness requirements shall be fulfilled throughtouyt the section of the screw.

2) For Stainless stell screws machined from bar it is permissible to use garde A1-70 for sizes ≤ M12 and A1-50 for sizes > M12 but they should be marked according to their property class.

Designation

A hexagon socket head cap screw with thread M5, nominal length l = 20 mm and property class 12.9 is designated as follows:
Hexagon socket head cap screw ISO 4762 - M5 X 20 - 12.9

Reference Documents

ISO 225: 1983, Fasteners-- Bolts, screws, studs and nuts -- Symbol and designation of dimensions.

ISO 261: 1973, ISO general purpose metric screw threads -- General plan

ISO 888: 1976, Bolts screws and nuts- Nominal lengths, and thread lengths for general purpose bolts.

ISO 898-1: 1988, Mechanical properties of fasteners - Part 1: Bolts, screws and studs.

ISO 965-2: 1980, ISO general purpose metric screw threads - Tolerantes - Part 2: Limits of sizes for general purpose bolt and nut threads - Medium quality.

ISO 965-3: 1980, ISO general purpose metric screw threads - Tolerantes - Part 3: Deviations for constructional thread.

ISO 3269: 1988, Fasteners - Acceptance inspection.

ISO 3506-1:1997, Mechanical properties of corrosion-resistant stainless steel fasteners - part 1: Bolts, screws and studs.

ISO 4042:1989, Fasteners - Electroplated coating.

ISO 4753:1989, Fasteners - Ends of parts with external metric ISO threads.

ISO 4759-1:1978, Tolerantes for fasteners - Part 1: Bolts, screws and nuts - product grades A, B and C

ISO 6157-1:1988, Fasteners - Surface discontinuities - Part 1: Bolts, screws and studs for general requirements.

ISO 6157-3:1988, Fasteners - Surface discontinuities - Part 3: Bolts, screws and studs for special requirements.

ISO 8839:1986, Mechanical properties of fasteners - Bolts, screws, studs and nuts made of non-ferrous metals.

ISO 8992:1986, Fasteners - General requirements for bolts, screws, studs and nuts.