ASME B18.2.1 Length Tolerance Chart for Bolts and Screws

ASME B18.2.1 Length Tolerance Chart for Bolts and Screws

Length Tolerances for Bolts

Nomianal Length Nominal Size
1/4 to 3/8 7/16 and 1/2 9/16 to 3/4 7/8 to 1 1 1/8 to 1 1/2 Over 1 1/2
Up to 1 in., incl. +0.02
-0.03		 +0.02
-0.03		 +0.02
-0.03		 ...
...		 ...
...		 ...
...
Over 1 in. to 2 1/2 in., incl. +0.02
-0.04		 +0.04
-0.06		 +0.06
-0.08		 +0.08
-0.10		 +0.12
-0.12		 +0.18
-0.18
Over 2 1/2 in. to 4 in., incl. +0.04
-0.06		 +0.06
-0.08		 +0.08
-0.10		 +0.10
-0.14		 +0.16
-0.16		 +0.20
-0.20
Over 4 in. to 6 in., incl. +0.06
-0.10		 +0.08
-0.10		 +0.10
-0.10		 +0.12
-0.16		 +0.18
-0.18		 +0.22
-0.22
Longer than 6 in. +0.10
-0.18		 +0.12
-0.18		 +0.14
-0.18		 +0.16
-0.20		 +0.22
-0.22		 +0.24
-0.24

Length Tolerances for Screws

Nomianal Length Nominal Size
1/4 to 3/8 7/16 and 1/2 9/16 to 3/4 7/8 to 1 1 1/8 to 1 1/2 Over 1 1/2
Up to 1 in., incl. +0.00
-0.03		 +0.00
-0.03		 +0.00
-0.03		 ...
...		 ...
...		 ...
...
Over 1 in. to 2 1/2 in., incl. +0.00
-0.04		 +0.00
-0.06		 +0.00
-0.08		 +0.00
-0.10		 +0.00
-0.12		 +0.00
-0.18
Over 2 1/2 in. to 4 in., incl. +0.00
-0.06		 +0.00
-0.08		 +0.00
-0.010		 +0.00
-0.14		 +0.00
-0.16		 +0.00
-0.20
Over 4 in. to 6 in., incl. +0.00
-0.10		 +0.00
-0.10		 +0.00
-0.10		 +0.00
-0.16		 +0.00
-0.18		 +0.00
-0.22
Longer than 6 in. +0.00
-0.18		 +0.00
-0.18		 +0.00
-0.18		 +0.00
-0.20		 +0.00
-0.22		 +0.00
-0.24

ASTM A193 Grade B8T Fastener Coatings

PTFE Coated B8T Fasteners
PTFE Coated
Black Phosphated B8T Fasteners
Black Phosphated
Zinc Plated B8T Fasteners
Zinc Plated
Hot Dip Galvanized B8T Fasteners
Hot Dip Galvanized
Cadium Plated B8T Fasteners
Cadium Plated
Ceramic Coated B8T Fasteners
Ceramic Coated
Zinc Nickel B8T Fasteners
Zinc Nickel
Zinc Flake Coated B8T Fasteners
Zinc Flake Coated