Heavy Hex Bolts

Several ASTM specifications require a hex head that is larger than a standard (finished) hex head. These specifications include: A193, A320 and A307B. Although A325 and A490 bolts also require a heavy hex head, please refer to Structural Bolts for dimensional specifications, since these bolts have shorter thread lengths than standard heavy hex bolts.

MANUFACTURING

Portland Bolt manufactures heavy hex bolts from 1/2” diameter through 2-1/2” diameter in most ASTM, AASHTO, and SAE specifications. Special tooling can be created to produce nonstandard head dimensions or bolt heads with your company’s name and/or logo.

STOCK

Portland Bolt stocks A325 Heavy Hex Structural Bolts.

STANDARD THREAD LENGTHS

Bolt lengths < 6”: Thread length = (2 X diameter) + 1/4”
Bolt lengths > 6”: Thread length = (2 X diameter) + 1/2”

Bolt Diameter	D	F			C		H
	Body Diameter	Width Across Flats			Width Across Corners		Height
	Max	Basic	Max	Min	Max	Min	Basic	Max	Min
1/2	0.515	7/8	0.875	0.850	1.010	0.969	11/32	0.364	0.302
5/8	0.642	1-1/16	1.062	1.031	1.227	1.175	27/64	0.444	0.378
3/4	0.768	1-1/4	1.250	1.212	1.443	1.383	1/2	0.524	0.455
7/8	0.895	1-7/16	1.438	1.394	1.660	1.589	37/64	0.604	0.531
1	1.022	1-5/8	1.625	1.575	1.876	1.796	43/64	0.700	0.591
1-1/8	1.149	1-13/16	1.812	1.756	2.093	2.002	3/4	0.780	0.658
1-1/4	1.277	2	2.00	1.938	2.309	2.209	27/32	0.876	0.749
1-3/8	1.404	2-3/16	2.188	2.119	2.526	2.416	29/32	0.940	0.810
1-1/2	1.531	2-3/8	2.375	2.300	2.742	2.622	1	1.036	0.902
1-3/4	1.785	2-3/4	2.750	2.662	3.175	3.035	1-5/32	1.196	1.054
2	2.039	3-1/8	3.125	3.025	3.608	3.449	1-11/32	1.388	1.175
2-1/4	2.305	3-1/2	3.500	3.388	4.041	3.862	1-1/2	1.548	1.327
2-1/2	2.559	3-7/8	3.875	3.750	4.474	4.275	1-21/32	1.708	1.479

Dimensions per ASME B18.2.1 1996

Specifications:
Industrial Applications: