Restricted End-Quench Hardenability Bands — 4140 RH to 50B40 RH
Tabulations of Band Limits
“J” Distance Sixteenths of an Inch	GRADE
	4140 RH		4145 RH		4161 RH		4320 RH		4620 RH		4820 RH		50B40 RH
	Max	Min	Max	Min	Max	Min	Max	Min	Max	Min	Max	Min	Max	Min
1	59	54	62	57	65	60	47	42	47	42	47	42	59	54
2	59	54	62	57	65	60	46	40	44	37	47	42	59	54
3	59	54	61	56	65	60	44	37	40	30	46	41	58	53
4	59	53	61	56	65	60	41	34	37	27	45	40	58	53
5	58	52	60	55	65	60	39	31	32	24	43	36	57	52
6	57	51	60	55	65	60	36	29	29	21	41	33	56	50
7	56	50	59	54	65	60	34	27	27	20	40	32	55	47
8	55	49	59	53	65	60	32	25	25	—	38	30	54	43
9	54	48	58	52	65	60	31	24	24	—	36	28	52	38
10	53	46	58	52	65	60	29	23	23	—	35	27	50	35
11	52	44	58	51	65	60	28	22	22	—	34	26	49	33
12	52	43	57	50	64	59	26	21	21	—	33	25	47	32
13	51	42	57	49	64	59	25	20	20	—	32	24	45	31
14	50	41	56	48	64	59	24	—	—	—	31	24	44	30
15	50	40	56	47	63	58	24	—	—	—	30	23	41	29
16	49	39	55	46	63	57	23	—	—	—	29	23	38	28
18	48	38	54	44	62	56	22	—	—	—	28	22	36	26
20	47	37	53	43	62	54	22	—	—	—	27	22	34	24
22	46	37	52	42	61	53	21	—	—	—	26	21	33	23
24	45	36	51	40	60	51	21	—	—	—	25	20	32	22
26	44	35	51	40	59	49	21	—	—	—	25	20	31	21
28	43	35	50	39	58	47	21	—	—	—	25	—	30	20
30	42	34	50	38	57	46	21	—	—	—	24	—	29	—
32	41	33	49	37	57	45	21	—	—	—	23	—	28	—

NOTE:

These values were adjusted to the nearest Rockwell “C” point, and are used when points are selected and specified.

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