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  4. BS EN 14399-8 Specification

BS EN 14399-8 HV Fit Bolts

BS EN 14399-8 Dimensions

Dimensions of fit bolts

Threadd M12 M16 M20 M22 M24 M27 M30 M36
Pa 1,75 2 2,5 2,5 3 3 3,5 4
b (ref) 23 28 33 34 39 41 44 52
c min. 0,4 0,4 0,4 0,4 0,4 0,4 0,4 0,4
max. 0,6 0,6 0,8 0,8 0,8 0,8 0,8 0,8
da max. 15,2 19,2 24,0 26,0 28,0 32,0 35,0 41,0
ds nom. 13 17 21 23 25 28 31 37
min. b 12,74 16,74 20,71 22,71 24,71 27,71 30,67 36,67
max. b 12,85 16,85 20,84 22,84 24,84 27,84 30,83 36,83
dw min. 20,1 24,9 29,5 33,3 38,0 42,8 46,6 55,9
max. c
e min. 23,91 29,56 35,03 39,55 45,20 50,85 55,37 66,44
k nom. 8 10 13 14 15 17 19 23
min. 7,55 9,25 12,10 13,10 14,10 16,10 17,95 21,95
kw max. 8,45 10,75 13,90 14,90 15,90 17,90 20,05 24,05
min. 5,28 6,47 8,47 9,17 9,87 11,27 12,56 15,36
r min. 1,2 1,2 1,5 1,5 1,5 2,0 2,0 2,0
s max. 22 27 32 36 41 46 50 60
min. 21,16 26,16 31,00 35,00 40,00 45,00 49,00 58,80
y max. 6,5 7,5 8,5 8,5 10,0 10,0 11,5 13,0
l 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.
50 48,75 51,25 20,5 27 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
55 53,50 56,50 25,5 32 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
60 58,50 61,50 30,5 37 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
65 63,50 66,50 35,5 42 29,5 37 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
70 68,50 71,50 40,5 47 34,5 42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
75 73,50 76,50 45,5 52 39,5 47 33,5 42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
80 78,50 81,50 50,5 57 44,5 52 38,5 47 37,5 46 . . . . . . . . . . . . . . . . . . . . . . . .
85 83,25 86,75 55,5 62 49,5 57 43,5 52 42,5 51 . . . . . . . . . . . . . . . . . . . . . . . .
90 88,25 91,75 60,5 67 54,5 62 48,5 57 47,5 56 41 51 . . . . . . . . . . . . . . . . . .
95 93,25 96,75 65,5 72 59,5 67 53,5 62 52,5 61 46 56 44 54 . . . . . . . . . . . .
100 98,25 101,75 . . . . . . 64,5 72 58,5 67 57,5 66 51 61 49 59 . . . . . . . . . . . .
105 103,25 106,75 . . . . . . 69,5 77 63,5 72 62,5 71 56 66 54 64 49,5 61 . . . . . .
110 108,25 111,75 . . . . . . 74,5 82 68,5 77 67,5 76 61 71 59 69 54,5 66 . . . . . .
115 113,25 116,75 . . . . . . 79,5 87 73,5 82 72,5 81 66 76 64 74 59,5 71 . . . . . .
120 118,25 1 21 ,75 . . . . . . 84,5 92 78,5 87 77,5 86 71 81 69 79 64,5 76 . . . . . .
125 123,0 127,0 . . . . . . 89,5 97 83,5 92 82,5 91 76 86 74 84 69,5 81 60 73
130 128,0 132,0 . . . . . . . . . . . . 88,5 97 87,5 96 81 91 79 89 74,5 86 65 78
135 133,0 137,0 . . . . . . . . . . . . 93,5 102 92,5 101 86 96 84 94 79,5 91 70 83
140 138,0 142,0 . . . . . . . . . . . . 98,5 107 97,5 106 91 101 89 99 84,5 96 75 88
145 143,0 147,0 . . . . . . . . . . . . 103,5 112 102,5 111 96 106 94 104 89,5 101 80 93
150 148,0 152,0 . . . . . . . . . . . . 108,5 117 107,5 116 101 111 99 109 94,5 106 85 98
155 153,0 159,0 . . . . . . . . . . . . 113,5 122 112,5 121 106 116 104 114 99,5 111 90 103
160 158,0 164,0 . . . . . . . . . . . . . . . . . . 117,5 126 111 121 109 119 104,5 116 95 108
165 163,0 169,0 . . . . . . . . . . . . . . . . . . 122,5 131 116 126 114 124 109,5 121 100 113
170 168,0 174,0 . . . . . . . . . . . . . . . . . . . . . . . . 121 131 119 129 114,5 126 105 118
175 173,0 179,0 . . . . . . . . . . . . . . . . . . . . . . . . 126 136 124 134 119,5 131 110 123
180 178,0 184,0 . . . . . . . . . . . . . . . . . . . . . . . . 131 141 129 139 124,5 136 115 128
185 182,7 189,6 . . . . . . . . . . . . . . . . . . . . . . . . 136 146 134 144 129,5 141 120 133
190 187,7 194,6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 149 134,5 146 125 138
195 192,7 199,6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 154 139,5 151 130 143
200 197,7 204,6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 159 144,5 156 135 148
  • NOTE Preferred lengths are defined in terms of lengths ls min and lg max.
  • a P is the p itch of thread .
  • b Corresponding to to lerance class b11 .
  • c dw max = s actual
  • d lg max = lnom - b; ls min = lg max - ymax

Dimensions of nuts

Threadd M12 M16 M20 M22 M24 M27 M30 M36
Pa 1,75 2 2,5 2,5 3 3 3,5 4
da max. 13,0 17,3 21,6 23,7 25,9 29,1 32,4 38,9
min. 12 16 20 22 24 27 30 36
dw max. b
min. 20,1 24,9 29,5 33,3 38,0 42,8 46,6 55,9
e min. 23,91 29,56 35,03 39,55 45,20 50,85 55,37 66,44
m nom. = max. 10 13 16 18 20 22 24 29
min. 9,64 12,30 14,90 16,90 18,70 20,70 22,70 27,70
mw min. 7,10 9,84 11,92 13,52 14,96 16,56 18,16 22,16
max. 22 27 32 36 41 46 50 60
s min. 21,16 26,16 31,00 35,00 40,00 45,00 49,00 58,80
  • a P is the p itch of thread .
  • b dw max = sactual

BS EN 14399-8 Specifications reference standards

Specifications for bolts and reference standards

Material Steel
General requirements EN 14399-1 and EN 14399-2
Thread Tolerance class 6g a
International Standards ISO 261, ISO 965-2
Mechanical properties Property class 10.9
European Standard EN ISO 898-1
Tolerances Product grade C except for dimensions c and r. Tolerance for lengths ≥ 155 mm: +IT17-1 / 2 IT17
European Standard EN ISO 4759-1
Finish-Coating b Uncoated as processed c
Hot dip galvanized EN ISO 10684
Others to be agreed d
Surface integrity Limits for surface discontinuities as specified in
Acceptability For acceptance procedure, see EN ISO 3269.
  • a The tolerance class specified applies to bolts without or before any coating. Hot-dip galvanized bolts are intended for assembly with nuts tapped oversize to 6AZ .
  • b Attention is drawn to the need to cons ider the risk of hydrogen embrittlement in the case of bolts of property class 10 .9 , when selecting an appropriate surface treatment process (e .g. cleaning and coating), see the relevant coating standards.
  • c “As processed” means the normal fin ish resulting from manufacture with a light coating of oil.
  • d Other coatings may be negotiated between the purchaser and the manufacturer provided they do not impair the mechanical properties or the functional characteristics . Coatings of cadm ium or cadmium alloys are not permitted .

Specifications for nuts and reference standards

Material Steel
General requirements EN 14399-1 and EN 14399-2
Thread Coating of the bolt Uncoated Hot dip galvanized Others
Tolerance class of the nut 6H 6AZ 6H a
International Standards ISO 261, ISO 965-2 ISO 261, ISO 965-5 ISO 261, ISO 965-2 , ISO 965-5
Mechanical properties Property class 10
European Standard EN ISO 898-2
Tolerances Product grade B
European Standard EN ISO 4759-1
Finish-Coating Uncoated as processed b
Hot dip galvanized EN ISO 10684
Others to be agreed c
Surface integrity Limits for surface discontinuities as specified in
Acceptability For acceptance procedure, see EN ISO 3269.
  • a For other coatings that need an increased fundamental deviation and according to the relevant standard, oversize tapped nuts with a thread to lerance class up to 6AZ may be used.
  • b “As processed” means the normal finish resulting from manufacture with a light coating of oil.
  • c Other coatings may be negotiated between the purchaser and the manufacturer provided they do not impair the mechanical properties or the functional characteristics. Coatings of cadmium or cadmium alloys are not permitted.

BS EN 14399-8 Bolting Surface Treatment Specifications

BS EN 14399-8 Bolting Components Marking

Product Shall be Marked with our manufacturing trade mark "TorqBolt" or "TB" along with the designated Grade.
Grade and manufacturer’s identification symbols shall be applied to one end of studs and to the heads of bolts and screws of all sizes. (If the available area is inadequate, the grade symbol may be marked on one end and the manufacturer’s identification symbol marked on the other end.) For bolts and screws smaller than 1⁄4 in. [6 mm] in diameter and studs smaller than 3⁄8 in. [10 mm] in diameter and for 1⁄4 in. [6 mm] in diameter studs requiring more than a total of three symbols, the marking shall be a matter of agreement between the purchaser and the manufacturer.

ASME Dimensional Standards

BS EN 14399-8 Bolting Certifications

  • EN 10204 3.1
  • EN 10204 3.2
  • PED 2014/68/EC
  • MERKBLATT AD 2000 W2/W7/W10
  • API 20 E BSL 1/ BSL 2
  • NACE MR 0175
  • NACE MR 0103

BS EN 14399-8 Testing Standards

ASME Threading Specifications

BS EN 14399-8 Supplementary Requirements