ASME/ANSI B16.34: Valve Pressure Temperature Ratings

Quick Reference

ASME B16.34 defines pressure-temperature ratings for flanged, threaded, and welding end valves. Classes: 150, 300, 600, 900, 1500, 2500, 4500. Material groups: Group 1 (carbon/alloy steel), Group 2 (stainless), Group 3 (nickel alloys). P-T charts show max pressure at temperature by class and material. Works with B16.10 (dimensions) and B16.5 (flange ratings).

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Need flange dimensions for valve connections? Download the ASME B16.5 Flange Chart or ASME B16.5 Bolt Chart.

ASME B16.34 For Valves

ASME B16.34 categorizes materials into several groups to standardize the application of valve materials across different temperature and pressure conditions. These groups help in selecting the appropriate material for valves based on operational requirements, ensuring compatibility with the fluid being handled and the environmental conditions of the application.

The material groups include various grades of carbon steel, stainless steel, alloy steel, and non-ferrous metals, each chosen for their specific properties like strength, corrosion resistance, and temperature tolerance.

ASME B16.34 mentions pipes, plates, and steel bars because it includes material specifications and grades for the manufacture of valve parts. These materials must meet specific standards to ensure that valves can safely operate under the pressure and temperature conditions for which they are rated.

Including these materials helps ensure compatibility and safety across various applications in piping systems.

ASME B16.34 Group 1 Materials: Carbon And Alloy

MaterialGroup No.	Material Nominal Designation	Forging	Casting	Plate	Bar	Tubular
1.1	CC-SIC-MN-SIC-MN-SI-V	A105A350 Gr. LF2A350 Gr. LF6 Cl.1	A216 Gr. WCB	A515 Gr. 70A516 Gr. 70A537 Gr. Cl.1	A675 Gr. 70A105A350 Gr. LF2A696 Gr. C	A672 Gr. B70A672 Gr. C70
1.2	C-SI2 1/2NI3 1/2NIC-MN-SIC-MN-SI-V	A350 Gr. LF3A350 Gr. LF6 Cl.2	A352 Gr. LC2A352 Gr. LC3A216 Gr. WCCA352 Gr. LCC	A203 Gr. BA203 Gr. E	A350 Gr. LF3	A106 Gr. C
1.3	CC-SI2 1/2NI3 1/2NIC-MN-SI	-	A352 Gr. LCB	A515 Gr. 65A203 Gr. AA203 Gr. DA516 Gr. 65	A675 Gr. 65	A672 Gr. B65A672 Gr. C65
1.4	CC-SIC-MN-SI	A350 Gr. LF1	-	A515 Gr. 60A516 Gr. 60	A675 Gr. 60A350 Gr. LF1A696 Gr. B	A106 Gr. BA672 Gr. B60A672 Gr. C60
1.5	C-1/2MO	A182 Gr. F1	A217 Gr. WC1A352 Gr. LC1	A204 Gr. AA204 Gr. B	A182 Gr. F1	A691 Gr. CM-70
1.6	C-1/2MO1/2CR-1/2MO1CR-1/2MO	-	-	A387 Gr. 2 Cl.1A387 Gr. 2 Cl.2A387 Gr. 12 Cl.1	-	A335 Gr. P1A369 Gr. FP1A691 Gr. 1/2CR
1.7	C-1/2MO1/2CR-1/2MONI-1/2CR-1/2MO3/4NI-MO-3/4CR	A182 Gr. F2	A217 Gr. WC4A217 Gr. WC5	A204 Gr. C	A182 Gr. F2	A691 Gr. MC-75
1.8	1CR-1/2MO1 1/4CR-1/2MO-SI2 1/4CR-1MO	-	-	A387 Gr. 12 Cl.2A387 Gr. 11 Cl.1A387 Gr. 22 Cl.1	-	A691 Gr. 1CRA335 Gr. P12A369 Gr. FP12A691 Gr. 1 1/4CRA335 Gr. P11A369 Gr. FP11A691 Gr. 2 1/4CRA335 Gr. P22A369 Gr. FP22
1.9	1CR-1/2MO1 1/4CR-1/2MO-SI1 1/4CR-1/2MO	A182 Gr. F12 Cl.2A182 Gr. F11 Cl.2	A217 Gr. WC6	A387 Gr. 11 Cl.2	A182 Gr. F12 Cl.2A182 Gr. F11 Cl.2A739 Gr. B11	-
1.10	2 1/4CR-1MO	A182 Gr. F22 Cl.3	A217 Gr. WC9	A387 Gr. 22 Cl.2	A182 Gr. F22 Cl.3A739 Gr. B22	-
1.11	3CR-1MOMN-1/2MOMN-s1/2MO-1/2NIMN-1/2MO-3/4NIC-MN-SI	A182 Gr. F21	-	A387 Gr. 21 Cl.2A302 Gr. A & BA302 Gr. CA302 Gr. DA537 Gr. CL2	A182 Gr. F21	-
1.12	5CR-1/2MO5CR-1/2MO-SI	-	-	A387 Gr. 5 Cl.1A387 Gr. 5 Cl.2	-	A691 Gr. 5CRA335 Gr. P5A369 Gr. FP5A335 Gr. P5b
1.13	5CR-1/2MO	A182 Gr. F5aA182 Gr. F5	A217 Gr. C5	-	A182 Gr. F5aA182 Gr. F5	-
1.14	9CR-1MO	A182 Gr. F9	A217 Gr. C12	-	A182 Gr. F9	-
1.15	9CR-1MO-V	A182 Gr. F51	A217 Gr. C12A	A387 Gr. 91 Cl.2	A182 Gr. F91	A335 Gr. P91

Group 1.1

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
1.1	CC-SIC-MN-SIC-MN-SI-V	A105 [1] [6]A350 Gr. LF2 [1]A350 Gr. LF6 Cl.1 [7]	A216 Gr. WCB [1]	A515 Gr. 70 [1]A516 Gr. 70 [1] [2]A537 Gr. Cl.1 [3]	A675 Gr. 70 [1] [4] [5]A105 [1] [6]A350 Gr. LF2 [1]A696 Gr. C	A672 Gr. B70 [1]A672 Gr. C70 [1]

[1] Upon prolonged exposure to temperatures above 800°F, the carbide phase of the steel may be converted to graphite. Permissible, but not recommended for prolonged use above 800°F. [2] Not to be used over 850°F. [3] Not to be used over 700°F. [4] Leaded grades shall not be used where welded of in any application above 500°F. [5] For service temperatures above 850°F, it is recommended that killed steels containing not less than 0.10% residual silicon be used. [6] Only killed steel shall be used above 850°F. [7] Not to be used over 500°F.

Maximum gage pressure (in psi) by temperature for Group 1.1 ASME B16.34 materials

Temp. °F	150#	300#	400#	600#	900#	1500#	2500#
-20 to 100	285	700	900	1480	2220	3705	6170
200	260	675	900	1350	2025	3375	5625
300	230	655	875	1315	1970	3280	5470
400	200	635	845	1270	1900	3170	5280
500	170	600	800	1200	1795	2995	4990
600	140	550	730	1095	1640	3735	4560
650	125	535	715	1075	1610	2685	4475
700	110	535	710	1005	1600	2665	4440
750	95	505	670	1010	1510	2520	4200
800	80	410	550	825	1235	2060	3430
850	65	270	355	535	805	1340	2230
900	50	170	230	345	515	860	1430
950	35	105	140	205	310	515	860
1000	20	50	70	105	155	260	430

Pro Tip

When reviewing valve datasheets, always verify the P-T rating at actual design temperature - not just the class at ambient. A Class 300 carbon steel valve rated at 700 psi at ambient is only good for 535 psi at 700°F. Many engineers get caught specifying valves based on class alone without checking the derating at elevated temperatures.

P-T ratings decrease with temperature: Valve pressure ratings are not fixed values; they decrease as operating temperature increases. Always consult the pressure-temperature chart for the specific material group and class to determine the maximum allowable working pressure at your design temperature.

Group 1.2

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
1.2	C-SI2 1/2 NI3 1/2 NIC-MN-SIC-MN-SI-V	A350 Gr. LF3 [2]A350 Gr. LF6 Cl.2 [4]	A352 Gr. LC2 [2]A352 Gr. LC3 [2]A216 Gr. WCC [1]A352 Gr. LCC [2]	A203 Gr. B [1]A203 Gr. E [1]	A350 Gr. LF3 [2]	A106 Gr. C [3]

[1] Upon prolonged exposure to temperatures above 800°F, the carbide phase of the steel may be converted to graphite. Permissible, but not recommended for prolonged use above 800°F. [2] Not to be used over 650°F. [3] Not to be used over 800°F. [4] Not to be used over 500°F.

Maximum gage pressure (in psi) by temperature for Group 1.2 ASME B16.34 materials

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	290	750	1000	1500	2250	3750	6250
200	260	750	1000	1500	2250	3750	6250
300	230	730	970	1455	2185	3640	6070
400	200	705	940	1410	2115	3530	5880
500	170	665	885	1330	1995	3325	5540
600	140	605	805	1210	1815	3025	5040
650	125	590	785	1175	1765	2940	4905
700	110	570	755	1135	1705	2840	4730
750	95	505	670	1010	1510	2520	4200
800	80	410	550	825	1235	2060	3430
850	65	270	355	535	805	1340	2230
900	50	170	230	345	515	860	1430
950	35	105	140	205	310	515	860
1000	20	50	70	105	155	260	430

Group 1.3

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
1.3	CC-SI2 1/2 NI3 1/2 NIC-MN-SI	-	A352 Gr. LCB [5]	A515 Gr. 65 [1]A203 Gr. A [1]A203 Gr. D [1]A516 Gr. 65 [1] [2]	A675 Gr. 65 [1] [3] [4]	A672 Gr. B65 [1]A672 Gr. C65 [1]

[1] Upon prolonged exposure to temperatures above 800°F, the carbide phase of the steel may be converted to graphite. Permissible, but not recommended for prolonged use above 800°F. [2] Not to be used over 850°F. [3] Leaded grades shall not be used where welded in any application above 500°F. [4] For service temperatures above 850°F, it is recommended that killed steel containing not less than 0.10% residual silicon be used. [5] Not to be used over 650°F.

Maximum gage pressure (in psi) by temperature for Group 1.3 ASME B16.34 materials

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	265	695	925	1390	2085	3470	5785
200	250	655	875	1315	1970	3280	5470
300	230	640	850	1275	1915	3190	5315
400	200	620	825	1235	1850	3085	5145
500	170	585	775	1165	1745	2910	4850
600	140	535	710	1065	1600	2665	4440
650	125	525	695	1045	1570	2615	4355
700	110	520	690	1035	1555	2590	4320
750	95	475	630	945	1420	2365	3945
800	80	390	520	780	1175	1955	3260
850	65	270	355	535	805	1340	2230
900	50	170	230	345	515	860	1430
950	35	105	140	205	310	515	860
1000	20	50	70	105	155	260	430

Group 1.4

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
1.4	CC-SIC-MN-SI	A350 Gr. LF1 [1]	-	A515 Gr. 60 [1] [2]A516 Gr. 60 [1] [2]	A675 Gr. 60 [1] [2] [3]A350 Gr. LF1 [1]A696 Gr. B	A106 Gr. B [1]A672 Gr. B60 [1]A672 Gr. C60 [1]

[1] Upon prolonged exposure to temperatures above 800°F, the carbide phase of the steel may be converted to graphite. Permissible, but not recommended for prolonged use above 800°F. [2] Not to be used over 850°F. [3] Leaded grades shall not be used where welded in any application above 500°F.

Maximum gage pressure (in psi) by temperature for Group 1.4 ASME B16.34 materials:

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	235	620	825	1235	1850	3085	1545
200	215	560	750	1125	1685	2810	4680
300	210	550	730	1095	1640	2735	4560
400	200	530	705	1060	1585	2645	4405
500	170	500	665	995	1495	2490	4150
600	140	455	610	915	1370	2285	3805
650	125	450	600	895	1345	2245	3740
700	110	450	600	895	1345	2245	3740
750	95	445	590	885	1325	2210	3685
800	80	370	495	740	1110	1850	3085
850	65	270	355	535	805	1340	2230
900	50	170	230	345	515	860	1430
950	35	105	140	205	310	515	860
1000	20	50	70	105	155	260	430

Group 1.5

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
1.5	C-1/2MO	A182 Gr. F1 [1]	A217 Gr. WC1 [1] [2]A352 Gr. LC1 [3]	A204 Gr. A [1]A204 Gr. B	A182 Gr. F1 [1]	A691 Gr. CM-70 [1]

[1] Upon prolonged exposure to temperatures above 875°F, the carbide phase of carbon-molybdenum steel may be converted to graphite. Permissible, but not recommended for prolonged use above 875°F. [2] Use normalized and tempered material only. [3] Not to be used over 650°F.

Maximum gage pressure (in psi) by temperature for Group 1.5 ASME B16.34 materials

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	265	695	925	1390	2085	3470	5785
200	260	680	905	1360	2035	3395	5660
300	230	655	870	1305	1955	3260	5435
400	200	640	855	1280	1920	3200	5330
500	170	620	830	1245	1865	3105	5180
600	140	605	805	1210	1815	3025	5040
650	125	590	785	1175	1765	2940	4905
700	110	570	755	1135	1705	2840	4730
750	95	530	710	1065	1595	2660	4430
800	80	510	675	1015	1525	2540	4230
850	65	485	650	975	1460	2435	4060
900	50	450	600	900	1350	2245	3745
950	35	280	375	560	845	1405	2345
1000	20	165	220	330	495	825	1370

Group 1.6

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
1.6	C-1/2MO1/2CR-1/2MO1CR-1/2MO	-	-	A387 Gr. 2 Cl.1 [3]A387 Gr. 2 Cl.2 [3]A387 Gr. 12 Cl.1 [2]	-	A335 Gr. P1 [1] [3]A369 Gr. FP1 [1] [3]A691 Gr. 1/2CR [3]

[1] Upon prolonged exposure to temperatures above 875°F, the carbide phase of carbon-molybdenum steel may be converted to graphite. Permissible, but not recommended for prolonged use above 875°F. [2] Permissible, but not recommended for prolonged use above 1100°F. [3] Not to be used over 1000°F.

Maximum gage pressure (in psi) by temperature for Group 1.6 ASME B16.34 materials

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	225	590	790	1185	1775	2955	4930
200	225	590	790	1185	1775	2955	4930
300	225	590	790	1185	1775	2955	4930
400	200	570	765	1145	1775	2860	4765
500	170	550	735	1105	1655	2755	4595
600	140	535	710	1065	1600	2665	4440
650	125	525	695	1045	1570	2615	4355
700	110	510	685	1025	1535	2560	4270
750	95	475	630	945	1420	2365	3945
800	80	475	630	945	1420	2365	3945
850	65	460	615	920	1380	2295	3830
900	50	440	590	885	1325	2210	3685
950	35	315	420	630	945	1575	2630
1000	20	200	270	405	605	1010	1685
1050	20 [1]	155	205	310	465	770	1285
1100	20 [1]	95	130	190	290	480	800
1150	20 [1]	60	80	125	185	310	515
1200	15 [1]	40	50	75	115	190	315

ASME B16.34 Group 2 Materials: Stainless Steel

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
2.1	18CR-8NI	A182 Gr. F304A182 Gr. F304H	A351 Gr. CF3A351 Gr. CF8	A240 Gr. 304A240 Gr. 340H	A182 Gr. F304A182 Gr. F304HA479 Gr. 304A479 Gr. 304H	A312 Gr. TP304A312 Gr. TP304HA358 Gr. 304A376 Gr. TP304A376 Gr. TP304HA430 Gr. FP304A430 Gr. FP304H
2.2	16CR-12NI-2MO18CR-8NI18CR-13NI-3MO16CR-12NI-2MO19CR-10NI-3MO	A182 Gr. F316A182 Gr. F316H	A351 Gr. CF3AA351 Gr. CF8AA351 Gr. CF3MA351 Gr. CF8MA351 Gr. CG8M	A240 Gr. 316A240 Gr. 316HA240 Gr. 317	A182 Gr. F316A182 Gr. F316HA479 Gr. 316A479 Gr. 316H	A312 Gr. TP316A312 Gr. TP316HA358 Gr. 316A376 Gr. TP316A376 Gr. TP316HA430 Gr. FP316A430 Gr. FP316HA312 Gr. TP317
2.3	18CR-8NI16CR-12NI-2MO	A182 Gr. F304LA182 Gr. F316L	-	A240 Gr. 304LA240 Gr. 316L	A182 Gr. F304LA479 Gr. 304LA182 Gr. F316LA479 Gr. 316L	A312 Gr. TP304LA312 Gr. TP316L
2.4	18CR-10NI-TI	A182 Gr. F321A182 Gr. F321H	-	A240 Gr. 321A240 Gr. 321H	A182 Gr. F321A479 Gr. 321A182 Gr. F321HA479 Gr. 321H	A312 Gr. TP321A312 Gr. TP321HA358 Gr. 321A376 Gr. TP321A376 Gr. TP321HA430 Gr. FP321A430 Gr. FP321H
2.5	18CR-10NI-CB	A182 Gr. F347A182 Gr. F347HA182 Gr. F348A182 Gr. F348H	A351 Gr. CF8C	A240 Gr. 347A240 Gr. 347HA240 Gr. 348A240 Gr. 348H	A182 Gr. F347A182 Gr. F347HA182 Gr. F348A182 Gr. F348HA479 Gr. 347A479 Gr. 347HA479 Gr. 348A479 Gr. 348H	A312 Gr. TP347A312 Gr. TP347HA358 Gr. TP347A376 Gr. TP347A376 Gr. TP347HA376 Gr. TP348A430 Gr. FP347A430 Gr. FP347HA312 Gr. TP348A312 Gr. TP348H
2.6	25CR-12NI23CR-12NI	-	A351 Gr. CH8A351 Gr. CH20	A240 Gr. 309SA240 Gr. 309H	-	A312 Gr. TP309HA358 Gr. 309H
2.7	25CR-20NI	A182 Gr. F310H	A351 Gr. CK20	A240 Gr. 310SA240 Gr. 310H	A182 Gr. F310HA479 Gr. 310HA479 Gr. 310S	A312 Gr. TP310HA358 Gr. 310H
2.8	20CR-18NI-6MO22CR-5NI-3MO-N25CR-7NI-4MO-N24CR-10NI-4MO-V25CR-5NI-2MO-2CU25CR-7NI-3.5MO-W-CB25CR-7NI-3.5MO-N-CB-W	A182 Gr. F44A182 Gr. F51A182 Gr. F53A182 Gr. F55	A351 Gr. CK3MCuNA351 Gr. CE8MNA351 Gr. CD4MCuA351 Gr. CD3MWCuN	A240 Gr. S31254A240 Gr. S31803A240 Gr. S32750A240 Gr. S32760	A479 Gr. S31254A479 Gr. S31803A479 Gr. S32750	A312 Gr. S31254A358 Gr. S31254A789 Gr. S31803A790 Gr. S31803A789 Gr. S32750A790 Gr. S32750A789 Gr. S32760A790 Gr. S32760

Group 2.1

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
2.1	18CR-8NI	A182 Gr. F304 [1]A182 Gr. F304H	A351 Gr. CF3 [2]A351 Gr. CF8 [1]	A240 Gr. 304 [1]A240 Gr. 340H	A182 Gr. F304 [1]A182 Gr. F304HA479 Gr. 304 [1]A479 Gr. 304H	A312 Gr. TP304 [1]A312 Gr. TP304HA358 Gr. 304 [1]A376 Gr. TP304 [1]A376 Gr. TP304HA430 Gr. FP304 [1]A430 Gr. FP304H

[1] At temperatures over 1000°F, use only when the carbon content is 0.04% or higher. [2] Not to be used over 800°F.

Maximum gage pressure (in psi) by temperature for Group 2.1 ASME B16.34 materials

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	275	720	960	1440	2160	3600	6000
200	230	600	800	1200	1800	3000	5000
300	205	540	720	1080	1620	2700	4500
400	190	495	660	995	1490	2485	4140
500	170	465	620	930	1395	2330	3880
600	140	435	580	875	1310	2185	3640
650	125	430	575	860	1290	2150	3580
700	110	425	565	850	1275	2125	3540
750	95	415	555	830	1245	2075	3460
800	80	405	540	805	1210	2015	3360
850	65	395	530	790	1190	1980	3300
900	50	390	520	780	1165	1945	3240
950	35	380	510	765	1145	1910	3180
1000	20	320	430	640	965	1605	2675
1050	20 [1]	310	410	615	925	1545	2570
1100	20 [1]	255	345	515	770	1285	2145
1150	20 [1]	200	265	400	595	995	1655
1200	20 [1]	155	205	310	465	770	1285
1250	20 [1]	115	150	225	340	565	945
1300	20 [1]	85	115	170	255	430	715
1350	20 [1]	60	80	125	185	310	515
1400	20 [1]	50	65	95	145	240	400
1450	15 [1]	35	45	70	105	170	285
1500	10 [1]	25	35	55	80	135	230

[1] Use with buttweld valves only. The flanged end rating stops at 1000°F.

Group 2.2

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
2.2	16CR-12NI-2MO18CR-8NI18CR-13NI-3MO16CR-12NI-2MO19CR-10NI-3MO	A182 Gr. F316 [1]A182 Gr. F316H	A351 Gr. CF3A [2]A351 Gr. CF8A [2]A351 Gr. CF3M [3]A351 Gr. CF8M [1]A351 Gr. CG8M [4]	A240 Gr. 316 [1]A240 Gr. 316HA240 Gr. 317 [1]	A182 Gr. F316 [1]A182 Gr. F316HA479 Gr. 316 [1]A479 Gr. 316H	A312 Gr. TP316 [1]A312 Gr. TP316HA358 Gr. 316 [1]A376 Gr. TP316 [1]A376 Gr. TP316HA430 Gr. FP316 [1]A430 Gr. FP316HA312 Gr. TP317 [1]

[1] At temperatures over 1000°F, use only when carbon content is 0.04% or higher. [2] Not to be used over 650°F. [3] Not to be used over 850°F. [4] Not to be used over 1000°F.

Maximum gage pressure (in psi) by temperature for Group 2.2 ASME B16.34 materials

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	275	720	960	1440	2160	3600	6000
200	235	620	825	1240	1860	3095	5160
300	215	560	745	1120	1680	2795	4660
400	195	515	685	1025	1540	2570	4280
500	170	480	635	955	1435	2390	3980
600	140	450	600	900	1355	2255	3760
650	125	445	590	890	1330	2220	3700
700	110	430	580	870	1305	2170	3620
750	95	425	570	855	1280	2135	3560
800	80	420	565	845	1265	2110	3520
850	65	420	555	835	1255	2090	3480
900	50	415	555	830	1245	2075	3460
950	35	385	515	775	1160	1930	3220
1000	20	350	465	700	1050	1750	2915
1050	20 [1]	345	460	685	1030	1720	2865
1100	20 [1]	305	405	610	915	1525	2545
1150	20 [1]	235	315	475	710	1185	1970
1200	20 [1]	185	245	370	555	925	1545
1250	20 [1]	145	195	295	440	735	1230
1300	20 [1]	115	155	235	350	585	970
1350	20 [1]	95	130	190	290	480	800
1400	20 [1]	75	100	150	225	380	630
1450	20 [1]	60	80	115	175	290	485
1500	20 [1]	40	55	85	125	205	345

• *[1] Use with buttweld valves only. Flanged end rating stops at 1000°F.

Common Mistake

Assuming stainless steel valves maintain their full rating at high temperature. At 1000°F, a Class 300 F316 valve drops to just 350 psi - less than half its cold rating. For sustained high-temperature service, consider upgrading to a higher class or using chrome-moly materials.

ASME B16.34 Group 3 Materials: Nickel Alloys

MaterialGroup No.	Material NominalDesignation	Forging	Casting	Plate	Bar	Tubular
3.1	35NI-35FE-20CR-CB	B462 Gr. N08020	-	B463 Gr. N08020	B473 Gr. N08020	B464 Gr. N08020B468 Gr. N08020
3.2	99NI	B160 Gr. N02200	-	B162 Gr. N02200	B160 Gr. N02200	B161 Gr. N02200B163 Gr. N02200
3.3	99NI-Low C	B160 Gr. N02201	-	B162 Gr. N02201	B160 Gr. N02201	-
3.4	67NI-30CU67NI-30CU-S	B564 Gr. N04400B564 Gr. N04405	-	B127 Gr. N04400	B164 Gr. N04400B164 Gr. N04405	B165 Gr. N04400B163 Gr. N04400
3.5	72NI-15CR-8FE	B564 Gr. N06600	-	B168 Gr. N06600	B166 Gr. N06600	B167 Gr. N06600B163 Gr. N06600
3.6	33NI-42FE-21CR	B564 Gr. N08800	-	B409 Gr. N08800	B408 Gr. N08800	B163 Gr. N08800
3.7	65NI-28MO-2FE	B335 Gr. N10665	-	B333 Gr. N10665	B335 Gr. N10665	B662 Gr. N10665
3.8	54NI-16MO-15CR60NI-22CR-9MO-3.5CB62NI-28MO-5FE70NI-16MO-7CR-5FE61NI-16MO-16CR42NI-21.5CR-3MO-2.3CU	B564 Gr. N10276B564 Gr. N06625B335 Gr. N10001B573 Gr. N10003B574 Gr. N06455B425 Gr. N08825	-	B575 Gr. N10276B443 Gr. N06625B333 Gr. N10001B434 Gr. N10003B575 Gr. N06455B424 Gr. N08825	B574 Gr. N10276B446 Gr. N06625B335 Gr. N10001B573 Gr. N10003B574 Gr. N06455B425 Gr. N08825	B622 Gr. N10276B622 Gr. N10001B622 Gr. N06455B423 Gr. N08825
3.9	47NI-22CR-9MO-18FE	B572 Gr. N06002	-	B435 Gr. N06002	B572 Gr. N06002	B622 Gr. N06002
3.10	25NI-47FE-21CR-5MO	B672 Gr. N08700	-	B599 Gr. N08700	B672 Gr. N08700	-
3.11	44FE-25NI-21CR-MO	B649 Gr. N08904	-	B625 Gr. N08904	B649 Gr. N08904	B677 Gr. N08904
3.12	26NI-43FE-22CR-5MO47NI-22CR-20FE-7MO	B621 Gr. N08320B581 Gr. N06985	-	B620 Gr. N08320B582 Gr. N06985	B621 Gr. N08320B581 Gr. N06985	B622 Gr. N08320B622 Gr. N06985
3.13	49NI-25CR-18FE-6MONI-FE-CR-MO-CU-Low C	B581 Gr. N06975B564 Gr. N08031	-	B582 Gr. N06975B625 Gr. N08031	B581 Gr. N06975B649 Gr. N08031	B622 Gr. N06975B622 Gr. N08031
3.14	47NI-22CR-19FE-6MO	B581 Gr. N06007	-	B582 Gr. N06007	B581 Gr. N06007	B622 Gr. N06007
3.15	33NI-2FE-21CRNI-MONI-MO-CR	B564 Gr. N08810	B494 Gr. N-12MWB494 Gr. CW-12MW	B409 Gr. N08810	B408 Gr. N08810	B407 Gr. N08810
3.16	35NI-19CR-1 1/4SI	B511 Gr. N08330	-	B536 Gr. N08330	B511 Gr. N08330	B535 Gr. N08330
3.17	29NI-20.5CR-3.5CU-2.5MO	-	A351 Gr. CN-7M	-	-	-

Max Gage Pressure (in psi) by Temperature

Group 3.1

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	290	750	1000	1500	2250	3750	6250
200	260	720	960	1440	2160	3600	6000
300	230	715	950	1425	2140	3565	5940
400	200	675	900	1345	2020	3365	5610
500	170	655	875	1310	1965	3275	5460
600	140	605	805	1210	1815	3025	5040
650	125	590	785	1175	1765	2940	4905
700	110	570	755	1135	1705	2840	4730
750	95	530	710	1065	1595	2660	4430
800	80	510	675	1015	1525	2540	4230

Group 3.2

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	140	360	480	720	1080	1800	3000
200	140	360	480	720	1080	1800	3000
300	140	360	480	720	1080	1800	3000
400	140	360	480	720	1080	1800	3000
500	140	360	480	720	1080	1800	3000
600	140	360	480	720	1080	1800	3000

Group 3.3

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	90	240	320	480	720	1200	2000
200	85	230	305	455	685	1140	1900
300	85	225	300	445	670	1115	1860
400	85	215	290	430	650	1080	1800
500	85	215	290	430	650	1080	1800
600	85	215	290	430	650	1080	1800
650	85	215	290	430	650	1080	1800
700	85	215	290	430	650	1080	1800
750	80	210	280	420	635	1055	1760
800	80	205	270	410	610	1020	1700
850	65	205	270	410	610	1020	1700
900	50	140	185	280	415	695	1155
950	35	115	150	230	345	570	950
1000	20	95	125	185	280	465	770
1050	20 [1]	75	100	150	220	370	615
1100	20 [1]	60	80	125	185	310	515
1150	20 [1]	45	60	95	140	230	385
1200	15 [1]	35	50	75	110	185	310

[1] Use with buttweld valves only. The flanged end rating stops at 1000°F.

Group 3.4

Temp. °F	150	300	400	600	900	1500	2500
200	200	530	705	1055	1585	2640	4400
300	190	495	660	990	1485	2470	4120
400	185	480	635	955	1435	2390	3980
500	170	475	635	950	1435	2375	3960
600	140	475	635	950	1435	2375	3960
650	125	475	635	950	1435	2375	3960
700	110	475	635	950	1435	2375	3960
750	95	470	625	935	1405	2340	3900
800	80	460	610	915	1375	2290	3820
850	65	340	455	680	1020	1695	2830
900	50	245	330	495	740	1235	2055

Group 3.5

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	290	750	1000	1500	2250	3750	6250
200	260	750	1000	1500	2250	3750	6250
300	230	730	970	1455	2185	3640	6070
400	200	705	940	1410	2115	3530	5880
500	170	665	885	1330	1995	3325	5540
600	140	605	805	1210	1815	3025	5040
650	125	590	785	1175	1765	2940	4905
700	110	570	755	1135	1705	2840	4730
750	95	530	710	1065	1595	2660	4430
800	80	510	675	1015	1525	2540	4230
850	65	485	650	975	1460	2435	4060
900	50	450	600	900	1350	2245	3745
950	35	325	435	655	980	1635	2725
1000	20	215	290	430	650	1080	1800
1050	20 [1]	140	185	280	415	695	1155
1100	20 [1]	95	125	185	280	465	770
1150	20 [1]	70	90	135	205	340	565
1200	20 [1]	60	80	125	185	310	515

[1] Use with buttweld valves only. Flanged end rating stop at 1000°F.

Group 3.10

Temp. °F	150	300	400	600	900	1500	2500
-20 to 100	275	720	960	1440	2160	3600	6000
200	260	720	960	1440	2160	3600	6000
300	230	680	905	1360	2040	3400	5670
400	200	640	855	1280	1920	3205	5340
500	170	610	815	1225	1835	3060	5100
600	140	595	790	1190	1780	2970	4950
650	125	570	760	1140	1705	2845	4740

We recommend purchasing the ASME B16.34 specification from the ASME website to get a complete understanding of this topic.

Field Note

When replacing valves in existing systems, don’t just match the class - verify the material group. I’ve seen new valves fail inspection because the replacement used Group 1.1 material where the original was Group 1.5 for the higher temperature rating. Always check both the pressure class and the material group designation.