ASME B18.2.1 Hex Flange Screws, Inch Series

Dimensions of ASME B18.2.1 Hex Flange Screws

Nomianal Size or Basic product Diameter		Minimum Bearing Diam., B1	Maximum Runout of Bearing Surface FIM	Thread Length, LT		Maximum Transition Thread Length, Y		Ring T		Ring B
				L ≤ 6 in.	L > 6 in.	L ≤ 6 in.	L > 6 in.	Inside Diameter +0.0000 -0.0003	Min Thickness	Inside Diameter +0.0000 -0.0003	Min Thickness +0.0000 -0.0003
1/4	0.2500	0.480	0.010	0.750	1.000	0.400	0.650	0.4380	0.500	0.4093	0.0514
5/16	0.3125	0.600	0.011	0.875	1.125	0.417	0.667	0.5820	0.500	0.5483	0.0643
3/8	0.3750	0.730	0.012	1.000	1.250	0.438	0.688	0.6550	0.500	0.6183	0.0771
7/16	0.4375	0.850	0.013	1.125	1.375	0.464	0.714	0.7300	0.500	0.6853	0.0900
1/2	0.5000	0.980	0.014	1.250	1.500	0.481	0.731	0.8750	0.500	0.8253	0.1029
9/16	0.5625	1.100	0.015	1.375	1.625	0.750	0.750	0.9500	0.500	0.8953	0.1157
5/8	0.6250	1.230	0.017	1.500	1.750	0.773	0.773	1.0750	0.500	1.0343	0.1286
3/4	0.7500	1.470	0.020	1.750	2.000	0.800	0.800	1.3120	0.500	1.2343	0.1543