ANSI B16.5 FORGED FLANGES							Dimensions Inches
Nominal pipe size to which Reduction is to be moed to be specified by purchaser	Nominal Flange	Outside Diameter of Flange from Which Reduction is Being Maed							Smallest size Bare or tapping Requiring Hub Flange
		150 lb. Standard	300 lb. Standard	400 lb. Standard	600 lb. Standard	900 lb. Standard	1500 lb. Standard	2500 lb. Standard
	¾	3 7/8	4 5/8	4 5/8	4 5/8	5 1/8	5 1/8	5 ½	½
	1	4 ¼	4 7/8	4 7/8	4 7/8	5 7/8	5 7/8	6 ¼	½
	1 ¼	4 5/8	5 ¼	5 ¼	5 ¼	6 ¼	6 ¼	7 ¼	½
	1 ½	5	6 1/8	6 1/8	6 1/8	7	7	8	½
	2	6	6 ½	6 ½	6 ½	8 ½	8 ½	9 ¼	1
	2 ½	7	7 ½	7 ½	7 ½	9 5/8	9 5/8	10 ½	1 ¼
	3	7 ½	8 ¼	8 ¼	8 ¼	9 ½	10 ½	12	1 ¼
	3 ½	8 ½	9	9	9	-	-	-	1 ½
	4	9	10	10	10 ¾	11 ½	12 ¼	14	1 ½
	5	10	11	11	13	13 ¾	14 ¾	16 ½	1 ½
	6	11	12 ½	12 ½	14	15	15 ½	19	2 ½
	8	13 ½	15	15	16 ½	18 ½	19	21 ¾	3
	10	16	17 ½	17 ½	20	21 ½	23	26 ½	3 ½
	12	19	20 ½	20 ½	22	24	26 ½	30	3 ½
	14	21	23	23	23 ¾	25 ¼	-	-	3 ½
	16	23 ½	25 ½	25 ½	27	27 ¾	-	-	4
	18	25	28	28	29 ¼	31	-	-	4
	20	27 ½	30 ½	30 ½	32	33 ¾	-	-	4
	24	32	36	36	37	41	-	-	4
Note:
For reductions to size smaller than shown. Blind flange are tapped or bared for specified nominal pipe size.