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ASME B18.31.1M Metric Tap End Reduced Body Studs Dimensions Standards

ASME B18.31.1M Metric Tap End Reduced Body Studs standard covers the complete dimensional and general data for double end metric series studs recognized as an American National Standard.
Double end stud (tap end type): A stud designed to be installed in a tapped hole and usually with different threaded lengths on each end. The tap end studs covered by ASME B18.31.1M standard have the same thread form on each end with the length of the tap end threads equal to approximately 11⁄2 times the nominal thread diameter.
NOTE: Tap end studs in ASME B18.31.1M standard may be installed with a nut on each end. Similarly, one end may be set in a tapped hole, usually with a locking compound.
The inclusion of dimensional data in ASME B18.31.1M standard is not intended to imply that all products described are stock production items. Consumers should consult with suppliers concerning availability of products.
The Tables measurements are also converted into millimeters to make the information clearer and easier to understand.

ASME B18.31.1M Metric Tap End Reduced Body Studs Dimensions Drawings

ASME B18.31.1M Metric Tap End Reduced Body Studs Dimensions (mm)

Nominal Size
Diameter, D		 Tap End Length, BM Nut End Thread Length, B UMax.
= 2P		 Nominal Length, L Body Diameter, DS
L ≤ 125 125 < L ≤ 200 L > 200 Min. Max. Min. (by Length)
Min. Max. Min. Max. Min. Max. Range Incr. L ≤ 150 L > 150
M1.6 2.1 - 2.7 9.2 9.9 - - - - 0.7 25-50 5 - 1.60 1.29 1.29
M2 2.7 - 3.3 10 10.8 - - - - 0.8 25-50 5 - 2.00 1.65 1.65
M2.5 3.37 - 4.12 11 11.9 - - - - 0.9 30-50 5 - 2.50 2.12 2.12
M3 4.12 - 4.87 12 13 - - - - 1 30-50 5 - 3.00 2.58 2.58
M4 5.62 - 6.37 14 15.4 - - - - 1.4 35-90 5 - 4.00 3.43 3.43
M5 7.05 - 7.95 16 17.6 - - - - 1.6 40-90 5 - 5.00 4.36 4.36
M6 8.55 - 9.45 18 20 24 26 - - 2 50-90
100-160		 5
10		 5.21 6.00 5.82 5.70
M8 11.45 - 12.55 18 20.5 24 26.5 - - 2.5 50-90
≥ 100		 5
10		 7.04 8.00 7.78 7.64
M10 14.45 - 15.55 26 29 32 35 45 48 3 60-160
≥ 180		 10
20		 8.86 10.00 9.78 9.64
M12 17.45 - 18.55 30 33.5 36 39.5 49 52.5 3.5 60-160
≥ 180		 10
20		 10.68 12.00 11.73 11.57
M14 20.35 - 21.65 34 38 40 44 53 57 4 80-160
≥ 180		 10
20		 12.50 14.00 13.73 13.57
M16 23.35 - 30.65 38 42 44 48 57 61 4 90-160
≥ 180		 10
20		 14.50 16.00 15.73 15.57
M20 29.35 - 30.65 46 51 52 57 65 70 5 100-160
≥ 180		 10
20		 18.16 20.00 19.67 19.48
M24 35.2 - 36.8 54 60 60 66 73 79 6 130-160
≥ 180		 10
20		 21.80 24.00 23.67 23.48
M30 43.75 - 46.25 66 73 72 79 85 92 7 150-160
≥ 180		 10
20		 27.46 30.00 - 29.48
M36 52.5 - 55.5 78 86 84 92 97 105 8 ≥ 200 20 33.12 36.00 - 35.38
M42 61.5 - 64.5 90 99 96 105 109 118 9 ≥ 240 20 38.78 42.00 - 41.38
M48 70.5 - 73.5 - - 108 118 121 131 10 ≥ 280 20 44.43 48.00 - 47.38
M56 82.25 - 85.75 - - 124 135 137 148 11 ≥ 300 20 52.09 56.00 - 55.26
M64 94.5 - 97.5 - - 140 152 153 165 12 ≥ 340 20 59.74 64.00 - 63.26
M72 106.5 - 109.5 - - 156 168 169 181 12 ≥ 380 20 67.74 72.00 - 71.26
M80 118.5 - 121.5 - - 172 184 185 197 12 ≥ 400 20 75.74 80.00 - 79.26
M90 133 - 137 - - - - 205 217 12 ≥ 440 20 85.74 90.00 - 89.13
M100 148 - 152 - - - - 225 237 12 ≥ 480 20 95.72 100.00 - 99.13

ASME B18.31.1M Metric Tap End Reduced Body Studs Length Tolerances (mm)

Nominal Length Tolerance
Over Through
6 10 ± 0.29
10 18 ± 0.35
18 30 ± 0.42
30 50 ± 0.50
50 80 ± 0.95
80 120 ± 1.10
120 180 ± 1.25
180 250 ± 1.45
250 315 ± 1.60
315 400 ± 1.80
400 500 ± 2.00
>500 ... ± 5.00

ASME Material Specifications

ASTM A193/A193M Bolting, Stud Bolts, Screws
ASTM A320/A320M Bolting, Stud Bolts, Screws
ASTM A354 Bolts
ASTM A449 Hex Cap Screws, Bolts, Studs
ASTM A453/A453M Bolting, Stud Bolts, Screws, Nuts
ASTM A574/A574M Standard Specification for Alloy Steel Socket Head Cap Screws
ASTM A1014/A1014M UNS N07718 Bolting, Stud Bolts, Screws, Nuts
ASTM A1082/A1082M Bolting, Stud Bolts, Screws, Nuts
ASTM F1554 Anchor Bolts, Anchor Rods
ASTM F2882 Stud Bolts, Screws, Threaded Rod
ASTM F3042 Socket Set, Square Head Slotted Headless Screw
ASTM F3125/F3125M Heavy Hex Bolts, Screws, Studs
ASTM F468/F468M Bolting, Stud Bolts, Screws
ASTM F593 Bolting, Stud Bolts, Screws
ASTM F738/F738M Stud Bolts, Screws
ASTM F835/F835M Standard Specification for Alloy Steel Socket Button and Flat Countersunk Head Cap Screws
ASTM F837/F837M Standard Specification for Stainless Steel Socket Head Cap Screws
ASTM F880/F880M Standard Specification for Stainless Steel Socket Set Screws
ASTM F901 Aluminium Transmission Tower Bolts
ASTM F912/912M Standard Specification for Alloy Steel Socket Set Screws

EN Material Specifications

EN 10269 Bolting Fasteners, Bolting Stud Bolts, Screws, Nuts, Washers

ISO Material Specifications

ISO 898-1 Bolting Fasteners, Bolting Stud Bolts, Screws
ISO 3506-1 Bolting, Stud Bolts, Screws, Nuts
ISO 3506-5 Bolting, Stud Bolts, Screws, Nuts