Dimensions
JIS B2220 16K flanges

Updated May 2026

JIS 5K B2220

JIS 16K B2220

JIS 20K B2220

JIS 30K B2220

Weld Neck (RF)

Slip On (FF)

Socket Weld (FF)

Lap Joint

Blind (FF)

NPS MM IN		OD	T	T1	L	L1	PCD	BH#	BHØ
10	3/8	90	12	12	16	31	65	4	15
15	1/2	95	12	12	16	32	70	4	15
20	3/4	100	14	14	20	34	75	4	15
25	1	125	14	14	20	36	90	4	19
32	1 1/4	135	16	16	22	39	100	4	19
40	1 1/2	140	16	16	24	39	105	4	19
50	2	155	16	16	24	40	120	8	19
65	2 1/2	175	18	18	26	46	140	8	19
80	3	200	20	20	28	49	160	8	23
90	3 1/2	210	20	20	30	50	170	8	23
100	4	225	22	22	34	56	185	8	23
125	5	270	22	22	34	59	225	8	25
150	6	305	24	24	38	69	260	12	25
200	8	350	26	26	40	73	305	12	25
250	10	430	28	28	44	81	380	12	27
300	12	480	30	30	48	88	430	16	27
350	14	540	34	34	52	104	480	16	33
400	16	605	38	38	60	114	540	16	33
450	18	675	40	40	64	126	605	20	33
500	20	730	42	42	68	134	660	20	33
550	22	795	44	44	70	135	720	20	39
600	24	845	46	46	74	147	770	24	39
650	26	895	48	N/A	77	N/A	820	24	39
700	28	960	50	N/A	80	N/A	875	24	42
750	30	1020	52	N/A	83	N/A	935	24	42
800	32	1085	54	N/A	86	N/A	990	24	48
850	34	1135	56	N/A	89	N/A	1040	24	48
900	36	1185	58	N/A	93	N/A	1090	28	48
1000	40	1320	62	N/A	99	N/A	1210	28	56

Notes..

Dimensions are in millimeters unless otherwise indicated
NPS = Nominal Pipe Size
OD = Outside Diameter of flange
T = Thickness min of all flanges
T1 = Thickness min of blind flange
L = Height of Slip On, Socket Weld and Lap Joint flange
L1 = Height of Weld Neck flange
PCD = Pitch Circle Diameter
BH# = Bolt Hole numbers
BHØ = Bolt Hole diameter
D = Depth of Socket Weld flange (currently unavailable)
Threaded flanges are currently not available

Flange Facing Dimensions in MM

Raised Face design

Flat Face design

NPS	RF large										RF small
	5K		10K		16K		20K		30K		RF small
	G	B	G	B	G	B	G	B	G	B	G1	B1
10	39	1	46	1	46	1	46	1	52	1	35	1
15	44	1	51	1	51	1	51	1	55	1	42	1
20	49	1	56	1	56	1	56	1	60	1	50	1
25	59	1	67	1	67	1	67	1	70	1	60	1
32	70	2	76	2	76	2	76	2	80	2	68	2
40	75	2	81	2	81	2	81	2	90	2	75	2
50	85	2	96	2	96	2	96	2	105	2	90	2
65	110	2	116	2	116	2	116	2	130	2	105	2
80	121	2	126	2	132	2	132	2	140	2	120	2
90	131	2	136	2	145	2	145	2	150	2	130	2
100	141	2	151	2	160	2	160	2	160	2	145	2
125	176	2	182	2	195	2	195	2	195	2	170	2
150	206	2	212	2	230	2	230	2	235	2	205	2
175	232	2	237	2
200	252	2	262	2	275	2	275	2	280	2	260	2
225	277	2	282	2
250	317	2	324	2	345	2	345	2	345	2	315	2
300	360	3	368	3	395	3	395	3	405	3	375	3
350	403	3	413	3	440	3	440	3	450	3	415	3
400	463	3	475	3	495	3	495	3	510	3	465	3
450	523	3	530	3	560	3	560	3
500	573	3	585	3	615	3	615	3
550	630	3	640	3	670	3	670	3
600	380	3	690	3	720	3	720	3
650	735	3	740	3	770	5	790	5
700	785	3	800	3	820	5	840	5
750	840	3	855	3	880	5	900	5
800	890	3	905	3	930	5	960	5
850	940	3	955	3	980	5	1020	5
900	990	3	1005	3	1030	5	1070	5
1000	1090	3	1110	3	1140	5

Raised Face (RF) JIS flange
is a pipe flange conforming to the Japanese industrial standard (JIS B2220) in which the gasket surface is positioned higher than the plane of the bolt circle. This design concentrates the bolt pressure on a smaller gasket surface, resulting in a stronger, tighter, and more reliable leak-free seal.

Flat Face (FF) JIS flange
is a pipe flange that conforms to the Japanese Industrial Standard (JIS) and has a completely smooth, flat sealing surface. Unlike raised surface (RF) flanges, they use gaskets that cover the entire flange surface, from the inner bore to the outer bolt circle.

Dimensions JIS B2220 16K flanges

Flange Facing Dimensions in MM

Dimensions
JIS B2220 16K flanges