STANDARD · ASME-B16-47-A

ASME B16.47 Series A Flange Dimensions

ASME B16.47-2025 · ASME B16.47 Series A

ASME B16.47-2025North America, Middle Eastpressure class

ASME B16.47 covers large-diameter flanges from NPS 26 to NPS 60. Series A preserves the former MSS SP-44 dimensions and is the series most often specified for large-bore oil and gas, water and process piping.

Series A and Series B use different outside diameters and bolt patterns for the same size and class, so the series must be stated on the purchase order. A Series A flange will not bolt to a Series B flange, and neither will bolt to an ASME B16.5 flange of the same nominal size. B16.47 covers weld-neck and blind flanges only — slip-on flanges above NPS 24 are made to drawing — and Class 900 is published up to NPS 48.

Base materialASTM A105

Size notationNPS (inch)

Material options5 groups

Reference data5 topics

DIMENSIONS

Dimension tables

One row per specification. Open a size for the drawing, pressure ratings and printable A4 sheet.

Weld Neck 84 Blind 84

Weld Neck: Butt-welded to the pipe with a tapered hub; used for high pressure, high temperature and cyclic service. 84 specifications.

84 specifications

Size	Rating	Outside Ø D	Thickness C	Raised face D2	Bolt circle K	Bolting	Hub A	Length H	Weight
26″DN650	Class 150	870	66.8	749	806.4	24 × Ø34.9	676	119	136 kg	Spec sheet
26″DN650	Class 300	972	78	749	876.3	28 × Ø44.5	721	183	274 kg	Spec sheet
26″DN650	Class 400	972	88.9	749	876.3	28 × Ø47.6	727	194	295 kg	Spec sheet
26″DN650	Class 600	1016	108	749	914.4	28 × Ø50.8	748	222	426 kg	Spec sheet
26″DN650	Class 900	1086	139.7	749	952.5	20 × Ø73	775	286	692 kg	Spec sheet
28″DN700	Class 150	927	69.8	800	863.6	28 × Ø34.9	727	124	156 kg	Spec sheet
28″DN700	Class 300	1035	84.3	800	939.8	28 × Ø44.5	775	195	338 kg	Spec sheet
28″DN700	Class 400	1035	95.3	800	939.8	28 × Ø50.8	783	206	356 kg	Spec sheet
28″DN700	Class 600	1073	111.3	800	965.2	28 × Ø54	803	235	481 kg	Spec sheet
28″DN700	Class 900	1168	142.7	800	1022.4	20 × Ø79.4	832	298	821 kg	Spec sheet
30″DN750	Class 150	984	73.2	857	914.4	28 × Ø34.9	781	135	181 kg	Spec sheet
30″DN750	Class 300	1092	90.7	857	997	28 × Ø47.6	827	208	395 kg	Spec sheet
30″DN750	Class 400	1092	101.6	857	997	28 × Ø54	837	219	411 kg	Spec sheet
30″DN750	Class 600	1130	114.3	857	1022.4	28 × Ø54	862	248	549 kg	Spec sheet
30″DN750	Class 900	1232	149.4	857	1085.8	20 × Ø79.4	889	311	962 kg	Spec sheet
32″DN800	Class 150	1060	79.5	914	977.9	28 × Ø41.3	832	143	229 kg	Spec sheet
32″DN800	Class 300	1149	97	914	1054.1	28 × Ø50.8	881	221	456 kg	Spec sheet
32″DN800	Class 400	1149	108	914	1054.1	28 × Ø54	889	232	483 kg	Spec sheet
32″DN800	Class 600	1194	117.3	914	1079.5	28 × Ø60.3	917	260	624 kg	Spec sheet
32″DN800	Class 900	1314	158.8	914	1155.7	20 × Ø85.7	946	330	1154 kg	Spec sheet
34″DN850	Class 150	1111	81	965	1028.7	32 × Ø41.3	883	148	245 kg	Spec sheet
34″DN850	Class 300	1206	100.1	965	1104.9	28 × Ø50.8	937	230	519 kg	Spec sheet
34″DN850	Class 400	1206	111.3	965	1104.9	28 × Ø54	945	241	544 kg	Spec sheet
34″DN850	Class 600	1245	120.7	965	1130.3	28 × Ø60.3	973	270	699 kg	Spec sheet
34″DN850	Class 900	1397	165.1	965	1225.6	20 × Ø92.1	1006	349	1347 kg	Spec sheet
36″DN900	Class 150	1168	88.9	1022	1085.8	32 × Ø41.3	933	156	290 kg	Spec sheet
36″DN900	Class 300	1270	103.4	1022	1168.4	32 × Ø54	991	240	578 kg	Spec sheet
36″DN900	Class 400	1270	114.3	1022	1168.4	32 × Ø54	1000	251	608 kg	Spec sheet
36″DN900	Class 600	1314	124	1022	1193.8	28 × Ø66.7	1032	282	773 kg	Spec sheet
36″DN900	Class 900	1460	171.5	1022	1289	20 × Ø92.1	1064	362	1540 kg	Spec sheet
38″DN950	Class 150	1238	85.9	1073	1149.4	32 × Ø41.3	991	156	327 kg	Spec sheet
38″DN950	Class 300	1168	106.4	1029	1092.2	32 × Ø41.3	994	179	315 kg	Spec sheet
38″DN950	Class 400	1206	124	1035	1117.6	32 × Ø47.6	1003	206	424 kg	Spec sheet
38″DN950	Class 600	1270	152.4	1054	1162	28 × Ø60.3	1022	254	667 kg	Spec sheet
38″DN950	Class 900	1460	190.5	1099	1289	20 × Ø92.1	1073	353	1535 kg	Spec sheet
40″DN1000	Class 150	1289	88.9	1124	1200.2	36 × Ø41.3	1041	162	352 kg	Spec sheet
40″DN1000	Class 300	1238	112.8	1086	1155.7	32 × Ø44.5	1048	192	381 kg	Spec sheet
40″DN1000	Class 400	1270	130	1092	1174.8	32 × Ø50.8	1054	216	494 kg	Spec sheet
40″DN1000	Class 600	1321	158.8	1111	1212.8	32 × Ø60.3	1073	264	739 kg	Spec sheet
40″DN1000	Class 900	1511	196.9	1162	1339.8	24 × Ø92.1	1127	363	1642 kg	Spec sheet
42″DN1050	Class 150	1346	95.2	1194	1257.3	36 × Ø41.3	1092	170	404 kg	Spec sheet
42″DN1050	Class 300	1289	117.6	1137	1206.5	32 × Ø44.5	1099	199	431 kg	Spec sheet
42″DN1050	Class 400	1321	133.4	1143	1225.6	32 × Ø50.8	1108	224	540 kg	Spec sheet
42″DN1050	Class 600	1403	168.1	1168	1282.7	28 × Ø66.7	1127	279	921 kg	Spec sheet
42″DN1050	Class 900	1562	206.2	1213	1390.6	24 × Ø92.1	1176	371	1796 kg	Spec sheet
44″DN1100	Class 150	1403	100.1	1245	1314.4	40 × Ø41.3	1143	176	449 kg	Spec sheet
44″DN1100	Class 300	1353	122.4	1194	1263.6	32 × Ø47.6	1149	205	479 kg	Spec sheet
44″DN1100	Class 400	1384	139.7	1200	1282.7	32 × Ø54	1159	233	624 kg	Spec sheet
44″DN1100	Class 600	1454	173	1226	1333.5	32 × Ø66.7	1181	289	980 kg	Spec sheet
44″DN1100	Class 900	1648	214.3	1270	1463.5	24 × Ø98.4	1235	391	1950 kg	Spec sheet
46″DN1150	Class 150	1454	101.6	1295	1365.2	40 × Ø41.3	1197	184	481 kg	Spec sheet
46″DN1150	Class 300	1416	127	1245	1320.8	28 × Ø50.8	1203	214	560 kg	Spec sheet
46″DN1150	Class 400	1441	146.1	1257	1339.8	36 × Ø54	1213	244	692 kg	Spec sheet
46″DN1150	Class 600	1511	179.4	1276	1390.6	32 × Ø66.7	1235	300	1093 kg	Spec sheet
46″DN1150	Class 900	1734	225.6	1334	1536.7	24 × Ø104.8	1292	411	2105 kg	Spec sheet
48″DN1200	Class 150	1511	106.4	1359	1422.4	44 × Ø41.3	1248	191	538 kg	Spec sheet
48″DN1200	Class 300	1467	131.8	1302	1371.6	32 × Ø50.8	1254	222	626 kg	Spec sheet
48″DN1200	Class 400	1511	152.4	1308	1403.4	28 × Ø60.3	1267	257	812 kg	Spec sheet
48″DN1200	Class 600	1594	188.9	1334	1460.5	32 × Ø73	1289	316	1295 kg	Spec sheet
48″DN1200	Class 900	1784	233.4	1384	1587.5	24 × Ø104.8	1343	419	2259 kg	Spec sheet
50″DN1250	Class 150	1568	109.7	1410	1479.6	44 × Ø47.6	1302	202	576 kg	Spec sheet
50″DN1250	Class 300	1530	138.2	1359	1428.8	32 × Ø54	1305	230	694 kg	Spec sheet
50″DN1250	Class 400	1568	157.2	1362	1460.5	32 × Ø60.3	1321	268	885 kg	Spec sheet
50″DN1250	Class 600	1670	196.9	1384	1524	28 × Ø79.4	1343	329	1510 kg	Spec sheet
52″DN1300	Class 150	1626	114.3	1461	1536.7	44 × Ø47.6	1353	208	640 kg	Spec sheet
52″DN1300	Class 300	1581	143	1410	1479.6	32 × Ø54	1356	237	753 kg	Spec sheet
52″DN1300	Class 400	1619	162.1	1413	1511.3	32 × Ø60.3	1372	276	964 kg	Spec sheet
52″DN1300	Class 600	1721	203.2	1435	1574.8	32 × Ø79.4	1394	337	1615 kg	Spec sheet
54″DN1350	Class 150	1683	119.1	1511	1593.8	44 × Ø47.6	1403	214	719 kg	Spec sheet
54″DN1350	Class 300	1657	150.9	1467	1549.4	28 × Ø60.3	1410	251	930 kg	Spec sheet
54″DN1350	Class 400	1702	169.9	1470	1581.2	28 × Ø66.7	1425	289	1163 kg	Spec sheet
54″DN1350	Class 600	1778	209.6	1492	1632	32 × Ø79.4	1448	349	1778 kg	Spec sheet
56″DN1400	Class 150	1746	122.4	1575	1651	48 × Ø47.6	1457	227	798 kg	Spec sheet
56″DN1400	Class 300	1708	152.4	1518	1600.2	28 × Ø60.3	1464	259	977 kg	Spec sheet
56″DN1400	Class 400	1753	174.8	1527	1632	32 × Ø66.7	1480	298	1229 kg	Spec sheet
56″DN1400	Class 600	1854	217.5	1543	1695.4	32 × Ø85.7	1502	362	1941 kg	Spec sheet
58″DN1450	Class 150	1803	127	1626	1708.2	48 × Ø47.6	1508	233	869 kg	Spec sheet
58″DN1450	Class 300	1759	157.2	1575	1651	32 × Ø60.3	1514	265	1030 kg	Spec sheet
58″DN1450	Class 400	1803	177.8	1578	1682.8	32 × Ø66.7	1530	306	1465 kg	Spec sheet
58″DN1450	Class 600	1905	222.3	1600	1746.2	32 × Ø85.7	1553	370	2105 kg	Spec sheet

REFERENCE

Pressure ratings, materials and tolerances

Transcribed from ASME B16.47-2025 with table and page references.

Pressure-temperature ratings

ASME B16.47-2025 pressure–temperature ratings (Group 1.1)

Table 3 (SI, bar) and Table 3C (U.S. customary, psig) of ASME B16.47-2025 give the maximum working pressure o…

Open reference Material groups

ASME B16.47-2025 material groups (Table 1)

ASME B16.47-2025 sorts every permitted flange material into a numbered group, and the group number — not the …

Open reference Tolerances

ASME B16.47-2025 flange tolerances (Section 7)

Section 7 of ASME B16.47-2025 sets the permissible manufacturing deviations for large-diameter flanges: raise…

Open reference Marking

ASME B16.47-2025 marking requirements (Section 4)

Section 4 of ASME B16.47-2025 defines the identification markings that must appear on every large-diameter fl…

Open reference Edition changes

ASME B16.47-2025 changes and record numbers

ASME B16.47-2025 was approved by the American National Standards Institute on 4 March 2025 and issued on 30 M…

Open reference

How to read the pressure class

Series A follows the former MSS SP-44 dimensions. Ratings are ASME classes 150, 300, 400, 600 and 900, with allowable pressures read from the B16.47 pressure–temperature tables for the material group and design temperature.

Edition and verification

Dimension values on this page have been checked against ASME B16.47-2025 (SI tables, cross-checked against the U.S. Customary tables). The 2025 edition prints exact metric equivalents of the inch dimensions rather than the old 5 mm-rounded values (for example 36.50 in is printed as 927 mm, not 925 mm), and defines flange thickness as excluding the raised face. Both corrections are reflected here; Series B NPS 38 and above follows Series A per the standard’s General Note (h).

Data imported 2026-11-05 08:05.