ASTM A307 Specification

The ASTM A307 specification covers carbon steel bolts and studs ranging from 1/4" through 4" diameter. This is your everyday, run of the mill bolt specification often manufactured using A36 round bar. There are three grades A, B, and C* which denote tensile strength, configuration, and application. Refer to the Mechanical Properties Chart for the subtle strength differences within each grade.

RELIABLE PIPES & TUBES LTD. Manufactures,Stocks & Supplies Bolts,Studs,Threaded Bars/Rods as Specified under Specification ASTM A307 Grade A,Grade B & Grade C.

Mechanical Properties


Grade Tensile, ksi Yield, min, ksi Elong %, min
A 60 min -- 18
B 60 - 100 -- 18
C* 58 - 80 36 23

Chemical Compositions


Element Grade A Grade B
Carbon, max 0.29% 0.29%
Manganese, max 1.20% 1.20%
Phosphorus, max 0.04% 0.04%
Sulfur, max 0.15% 0.05%

Nuts & Washers Recommended

Nuts Washers
A307 Grades A & C* A307 Grade B
1/4 - 1-1/2 1-5/8 - 4 1/4 - 4
A563A Hex A563A Heavy Hex A563A Heavy Hex F844