Our factory specialized in tower Bolts manufacturing, A394 Tower Bolts and Step Bolts that meet all ASTM Specifications.
custom manufacture any size of step bolt to any type of A394 Bolt you require.
supply and manufacture Tower bolts ranging in diameter from ½” – 1” and to any length that you require.
We can supply Tower bolts and Step bolts that will pass Charpy V-Notch testing that are required for certain specific projects.
Nominal Size, in Minimum Tensile Load, lbp
Type 0B Types 1 and 3C
1/2 10,500 17,050
5/8 16,700 27,100
3/4 24,700 40,100
7/8 34,200 55,450
1 44,850 72,700NOTES
Tensile stength based on the thread stress area A is calculated as follows:
A=0.7854[D-(0.9743/N)]2
where D = nominal Diameter, and
N = threads per inch.
B Based on 74,000 psi unit tensile strength.
C Based on 120,000 psi unit tensile strength.
A394 Tower Bolts come in the following Types/grades:
Type 0 – Hot-dip zinc coated bolts made of low or medium carbon steel
Type 1 – Hot-dip zinc coated bolts made of medium carbon steel, quenched and tempered
Type 2 – Withdrawn in 2005
Type 3 – Bare (uncoated). quenched and tempered bolts made of weathering steel
THE MOST COMMON TOWER BOLT USED IS TYPE 1
Recommended Nuts:
Unless otherwise specified, all nuts on these bolts shall be hex style and conform to the requirements of Specification A563; See below for bolt nut combinations.
Bolt Type Nut Grade Finish
0 A hot-dip zinc-coated
1 DH hot-dip zinc-coated
3 DH3 plain
Recommended Washers:
Suitable washers for use with Type 0 are hot-dip zinc-coated carbon-steel washers with dimensions that are in accordance with Specification F436.
Suitable washers for use With Type 1 bolts are hot-dip zinc- coated Type 1 hardened-steel washers that are in accordance with Specification F436.
Suitable washers for use with Type 3 bolts are Type 3 hardened-steel washers that are in accordance with Specification F436.
