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

Blind: A solid disc bolted over a line end or vessel opening for isolation, testing and future tie-ins. 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	—	—	318 kg	Spec sheet
26″DN650	Class 300	972	82.6	749	876.3	28 × Ø44.5	—	—	489 kg	Spec sheet
26″DN650	Class 400	972	98.6	749	876.3	28 × Ø47.6	—	—	573 kg	Spec sheet
26″DN650	Class 600	1016	125.4	749	914.4	28 × Ø50.8	—	—	798 kg	Spec sheet
26″DN650	Class 900	1086	160.3	749	952.5	20 × Ø73	—	—	1164 kg	Spec sheet
28″DN700	Class 150	927	69.8	800	863.6	28 × Ø34.9	—	—	378 kg	Spec sheet
28″DN700	Class 300	1035	88.9	800	939.8	28 × Ø44.5	—	—	596 kg	Spec sheet
28″DN700	Class 400	1035	104.6	800	939.8	28 × Ø50.8	—	—	689 kg	Spec sheet
28″DN700	Class 600	1073	131.8	800	965.2	28 × Ø54	—	—	935 kg	Spec sheet
28″DN700	Class 900	1168	171.5	800	1022.4	20 × Ø79.4	—	—	1442 kg	Spec sheet
30″DN750	Class 150	984	73.2	857	914.4	28 × Ø34.9	—	—	445 kg	Spec sheet
30″DN750	Class 300	1092	93.7	857	997	28 × Ø47.6	—	—	701 kg	Spec sheet
30″DN750	Class 400	1092	111.3	857	997	28 × Ø54	—	—	817 kg	Spec sheet
30″DN750	Class 600	1130	139.7	857	1022.4	28 × Ø54	—	—	1099 kg	Spec sheet
30″DN750	Class 900	1232	182.4	857	1085.8	20 × Ø79.4	—	—	1705 kg	Spec sheet
32″DN800	Class 150	1060	79.5	914	977.9	28 × Ø41.3	—	—	562 kg	Spec sheet
32″DN800	Class 300	1149	98.6	914	1054.1	28 × Ø50.8	—	—	814 kg	Spec sheet
32″DN800	Class 400	1149	115.9	914	1054.1	28 × Ø54	—	—	941 kg	Spec sheet
32″DN800	Class 600	1194	147.6	914	1079.5	28 × Ø60.3	—	—	1296 kg	Spec sheet
32″DN800	Class 900	1314	193.5	914	1155.7	20 × Ø85.7	—	—	2060 kg	Spec sheet
34″DN850	Class 150	1111	81	965	1028.7	32 × Ø41.3	—	—	628 kg	Spec sheet
34″DN850	Class 300	1206	103.4	965	1104.9	28 × Ø50.8	—	—	938 kg	Spec sheet
34″DN850	Class 400	1206	122.2	965	1104.9	28 × Ø54	—	—	1095 kg	Spec sheet
34″DN850	Class 600	1245	154	965	1130.3	28 × Ø60.3	—	—	1468 kg	Spec sheet
34″DN850	Class 900	1397	204.8	965	1225.6	20 × Ø92.1	—	—	2461 kg	Spec sheet
36″DN900	Class 150	1168	88.9	1022	1085.8	32 × Ø41.3	—	—	760 kg	Spec sheet
36″DN900	Class 300	1270	109.7	1022	1168.4	32 × Ø54	—	—	1104 kg	Spec sheet
36″DN900	Class 400	1270	128.6	1022	1168.4	32 × Ø54	—	—	1277 kg	Spec sheet
36″DN900	Class 600	1314	162.1	1022	1193.8	28 × Ø66.7	—	—	1724 kg	Spec sheet
36″DN900	Class 900	1460	214.3	1022	1289	20 × Ø92.1	—	—	2817 kg	Spec sheet
38″DN950	Class 150	1238	85.9	1073	1149.4	32 × Ø41.3	—	—	825 kg	Spec sheet
38″DN950	Class 300	1168	106.4	1029	1092.2	32 × Ø41.3	—	—	908 kg	Spec sheet
38″DN950	Class 400	1206	124	1035	1117.6	32 × Ø47.6	—	—	1111 kg	Spec sheet
38″DN950	Class 600	1270	155.4	1054	1162	28 × Ø60.3	—	—	1544 kg	Spec sheet
38″DN950	Class 900	1460	215.9	1099	1289	20 × Ø92.1	—	—	2836 kg	Spec sheet
40″DN1000	Class 150	1289	88.9	1124	1200.2	36 × Ø41.3	—	—	925 kg	Spec sheet
40″DN1000	Class 300	1238	112.8	1086	1155.7	32 × Ø44.5	—	—	1080 kg	Spec sheet
40″DN1000	Class 400	1270	130	1092	1174.8	32 × Ø50.8	—	—	1293 kg	Spec sheet
40″DN1000	Class 600	1321	162.1	1111	1212.8	32 × Ø60.3	—	—	1741 kg	Spec sheet
40″DN1000	Class 900	1511	223.8	1162	1339.8	24 × Ø92.1	—	—	3148 kg	Spec sheet
42″DN1050	Class 150	1346	95.2	1194	1257.3	36 × Ø41.3	—	—	1080 kg	Spec sheet
42″DN1050	Class 300	1289	117.6	1137	1206.5	32 × Ø44.5	—	—	1220 kg	Spec sheet
42″DN1050	Class 400	1321	133.4	1143	1225.6	32 × Ø50.8	—	—	1433 kg	Spec sheet
42″DN1050	Class 600	1403	171.5	1168	1282.7	28 × Ø66.7	—	—	2080 kg	Spec sheet
42″DN1050	Class 900	1562	231.6	1213	1390.6	24 × Ø92.1	—	—	3481 kg	Spec sheet
44″DN1100	Class 150	1403	100.1	1245	1314.4	40 × Ø41.3	—	—	1232 kg	Spec sheet
44″DN1100	Class 300	1353	122.4	1194	1263.6	32 × Ø47.6	—	—	1397 kg	Spec sheet
44″DN1100	Class 400	1384	139.7	1200	1282.7	32 × Ø54	—	—	1649 kg	Spec sheet
44″DN1100	Class 600	1454	177.8	1226	1333.5	32 × Ø66.7	—	—	2316 kg	Spec sheet
44″DN1100	Class 900	1648	242.9	1270	1463.5	24 × Ø98.4	—	—	4062 kg	Spec sheet
46″DN1150	Class 150	1454	101.6	1295	1365.2	40 × Ø41.3	—	—	1343 kg	Spec sheet
46″DN1150	Class 300	1416	127	1245	1320.8	28 × Ø50.8	—	—	1588 kg	Spec sheet
46″DN1150	Class 400	1441	146.1	1257	1339.8	36 × Ø54	—	—	1869 kg	Spec sheet
46″DN1150	Class 600	1511	185.7	1276	1390.6	32 × Ø66.7	—	—	2612 kg	Spec sheet
46″DN1150	Class 900	1734	255.6	1334	1536.7	24 × Ø104.8	—	—	4729 kg	Spec sheet
48″DN1200	Class 150	1511	106.4	1359	1422.4	44 × Ø41.3	—	—	1520 kg	Spec sheet
48″DN1200	Class 300	1467	131.8	1302	1371.6	32 × Ø50.8	—	—	1767 kg	Spec sheet
48″DN1200	Class 400	1511	152.4	1308	1403.4	28 × Ø60.3	—	—	2143 kg	Spec sheet
48″DN1200	Class 600	1594	195.3	1334	1460.5	32 × Ø73	—	—	3056 kg	Spec sheet
48″DN1200	Class 900	1784	263.5	1384	1587.5	24 × Ø104.8	—	—	5170 kg	Spec sheet
50″DN1250	Class 150	1568	109.7	1410	1479.6	44 × Ø47.6	—	—	1686 kg	Spec sheet
50″DN1250	Class 300	1530	138.2	1359	1428.8	32 × Ø54	—	—	2015 kg	Spec sheet
50″DN1250	Class 400	1568	158.8	1362	1460.5	32 × Ø60.3	—	—	2405 kg	Spec sheet
50″DN1250	Class 600	1670	203.2	1384	1524	28 × Ø79.4	—	—	3490 kg	Spec sheet
52″DN1300	Class 150	1626	114.3	1461	1536.7	44 × Ø47.6	—	—	1885 kg	Spec sheet
52″DN1300	Class 300	1581	143	1410	1479.6	32 × Ø54	—	—	2225 kg	Spec sheet
52″DN1300	Class 400	1619	163.5	1413	1511.3	32 × Ø60.3	—	—	2641 kg	Spec sheet
52″DN1300	Class 600	1721	209.6	1435	1574.8	32 × Ø79.4	—	—	3822 kg	Spec sheet
54″DN1350	Class 150	1683	119.1	1511	1593.8	44 × Ø47.6	—	—	2103 kg	Spec sheet
54″DN1350	Class 300	1657	150.9	1467	1549.4	28 × Ø60.3	—	—	2578 kg	Spec sheet
54″DN1350	Class 400	1702	171.5	1470	1581.2	28 × Ø66.7	—	—	3058 kg	Spec sheet
54″DN1350	Class 600	1778	217.5	1492	1632	32 × Ø79.4	—	—	4233 kg	Spec sheet
56″DN1400	Class 150	1746	122.4	1575	1651	48 × Ø47.6	—	—	2327 kg	Spec sheet
56″DN1400	Class 300	1708	152.4	1518	1600.2	28 × Ø60.3	—	—	2766 kg	Spec sheet
56″DN1400	Class 400	1753	176.2	1527	1632	32 × Ø66.7	—	—	3335 kg	Spec sheet
56″DN1400	Class 600	1854	225.6	1543	1695.4	32 × Ø85.7	—	—	4776 kg	Spec sheet
58″DN1450	Class 150	1803	127	1626	1708.2	48 × Ø47.6	—	—	2574 kg	Spec sheet
58″DN1450	Class 300	1759	157.2	1575	1651	32 × Ø60.3	—	—	3025 kg	Spec sheet
58″DN1450	Class 400	1803	180.8	1578	1682.8	32 × Ø66.7	—	—	3622 kg	Spec sheet
58″DN1450	Class 600	1905	231.6	1600	1746.2	32 × Ø85.7	—	—	5177 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.