Hex Jam Nuts

Hex Jam Nuts - ANSI / ASME B18.2.2 - 1987

Nominal Size or Basic Major Thread Diameter		F			G		H
		Width Across Flats			Width Across Corners		Thickness
		Basic	Max	Min	Max	Min	Basic	Max	Min
1/4	.2500	7/16	.438	.428	.505	.488	5/32	.163	.150
5/16	.3125	1/2	.500	.489	.577	.557	3/16	.195	.180
3/8	.3750	9/16	.562	.551	.650	.628	7/32	.227	.210
7/16	.4375	11/16	.688	.675	.794	.768	1/4	.260	.240
1/2	.5000	3/4	.750	.736	.866	.840	5/16	.323	.302
9/16	.5625	7/8	.875	.851	1.010	.982	5/16	.324	.301
5/8	.6250	15/16	.938	.922	1.093	1.051	3/8	.387	.363
3/4	.7500	1-1/8	1.125	1.088	1.299	1.240	27/64	.446	.398
7/8	.8750	1-5/16	1.312	1.269	1.516	1.447	31/64	.510	.458
1	1.0000	1-1/2	1.500	1.450	1.732	1.653	35/64	.575	.519
1-1/8	1.1250	1-11/16	1.688	1.631	1.949	1.859	39/64	.639	.579
1-1/4	1.2500	1/7/8	1.875	1.812	2.165	2.066	23/32	.751	.687
1-3/8	1.3750	2-1/16	2.062	1.994	2.382	2.273	25/32	.815	.747
1-1/2	1.5000	2-1/4	2.250	2.175	2.598	2.480	27/32	.880	.808
1-3/4	1.7500	2-5/8	2.625	2.538	3.031	2.893	31/32	1.009	.929
2	2.0000	3	3.000	2.900	3.464	3.306	1-3/32	1.138	1.050
2-1/4	2.2500	3-1/2	3.500	3.388	4.041	3.862	1-13/64	1.251	1.155
2-1/2	2.5000	3-7/8	3.875	3.750	4.474	4.275	1-29/64	1.505	1.401

Description	A six sided internally threaded fastener which is only 2/3 he thickness of a full form nut.
Applications & Advantages	Jam nuts are tightened against the work surface and a finished or heavy hex nut is tightened against the jam nut to keep it from loosening.
Material	Steel: Nuts shall be made from a low carbon steel which conforms to the following chemical composition requirements: Phosphorus: .12% max Carbon: .47% max Sulfur: .23% max Stainless: Nuts shall be made from one of the following austenitic stainless alloys" 303, 303SE, 304 or XM7, all of which have a chromium content of 18% and a nickel content of 8%.
Heat Treatment	The austenitic alloys develop their strength through work hardening during the manufacturing process, as seen from their hardness properties below. The only heat treatment normally available on austenitic stainless steel alloys is annealing, which is done at approximately 1900°F to a dead soft condition and is not normally thermally reversible.
Core Hardness	Steel: Rockwell B68 - C32 Stainless: Rockwell B95 - C32
Proof Load	Steel: Course thread: 54,000 psi Fine Thread: 48,000 psi Stainless: 1/4 thru 1/2 inch - 60,000 psi
Plating	See plating page for plating information.