BS 4504 PN25 Flange Dimensions

BS4504 PN 25 Dimensions

Note: Now obsolete and replaced by BS EN 1092-1 see flange index page.

DN = Nominal size, D = Outside Diameter, A = Outside Dia of Neck , B1 = Bore of Type 101 & 112 Flange, C1 = Thickness of Plate Flange,
C2 = Thickness of Weld_Neck and Boss Flange , N1 = Dia of Weld Neck ,N2 = Dia of Boss , R = corner Radius, H1 = Length of Boss Flange,
H2 = Length of Weld Neck Flange, H3 = Length of Neck :

Note: The flanges shown are only a small part of the range covered in BS 4504.

The Facings shown are type B (Raised Face). Other Facings include:
Type A..Flat: Type C..Tongue: Type D..Groove Type E..Spigot: :Type F..Recess: Type G..O-ring Recess: Type H.,0-ring Groove:

Note : All Dimensions in mm

DN	D	C1	C2	H1	H2	H3	R	A	N1	N2	B1	d1	f1
10	90	14	16	22	35	6	3	17,2	28	30	18	40	2
15	95	14	16	22	38	6	3	21,3	32	35	22	45	2
20	105	16	18	26	40	6	4	26,9	40	45	27,5	58	2
25	115	16	18	28	40	6	4	33,7	46	52	34,5	68	2
32	140	18	18	30	42	6	5	42,4	56	60	43,5	78	2
40	150	18	18	32	45	7	5	48,3	64	70	49,5	88	3
50	165	20	20	34	48	8	5	60,3	74	84	61,5	102	3
65	185	22	22	38	52	10	6	76,1	92	104	77,5	122	3
80	200	24	24	40	58	12	6	88,9	110	118	90,5	138	3
100	235	26	24	44	65	12	6	114,3	134	145	116	162	3
125	270	28	26	48	68	12	6	139,7	162	170	141,5	188	3
150	300	30	28	52	75	12	8	168,3	190	200	170,5	218	3
200	360	32	30	52	80	16	8	219,1	244	256	221,5	278	3
250	425	35	32	60	88	18	10	273,0	296	310	276,5	335	3
300	485	38	34	67	92	18	10	323,9	350	364	327,5	395	4
350	555	42	38	72	100	20	10	355,6	398	418	359,5	450	4
400	620	46	40	78	110	20	10	406,4	452	472	411,0	505	4
450	670	50	42	84	110	20	12	457,0	500	520	462,0	555	4
500	730	56	44	90	125	20	12	508,0	558	580	513,5	615	4
600	845	68	46	100	125	20	12	610,0	660	684	616,5	720	5
700	960	-	46		125	20	12	711,0	760			820	5
800	1085	-	50		135	22	12	813,0	864		-	930	5
900	1185	-	54		145	24	12	914,0	968		-	1030	5
1000	1320	-	58		155	24	12	1016,0	1070		-	1140	5
1200	1530	-	-	-			12	1220,0		-	-	1350	5
1400	1755	-	-	-			12	1420,0		-	-	1560	5
1600	1975	-	-	-			12	1620,0		-	-	1780	5
DN	D	C1	C2	H1	H2	H3	R	A	N1	N2	B1	d1	f1

Flange Bolting

K = Bolt Circle Diameter, L = Dia Of Bolt Hole,
No = Number of Holes , Size = Size of Bolts

DN	K	L	No	Size
mm	mm	mm	-	mm
10	60	14	4	M12
15	65	14	4	M12
20	75	14	4	M12
25	85	14	4	M12
32	100	18	4	M16
40	110	18	4	M16
50	125	18	4	M16
65	145	18	8	M16
80	160	18	8	M16
100	190	22	8	M20
125	220	26	8	M24
150	250	26	8	M24
200	310	26	12	M24
250	370	30	12	M27
300	430	30	16	M27
350	490	33	16	M30
400	550	36	16	M33
450	600	36	20	M33
500	660	36	20	M33
600	770	39	20	M36
700	875	42	24	M39
800	990	48	24	M45
900	1090	48	28	M45
1000	1210	56	28	M52
1200	1420	56	32	M52
1400	1640	62	36	M56
1600	1860	62	40	M56
DN	K	L	No	Size

Steel Flange Index