ASTM A182 F11 Flanges | ASME B16.5 | ASME B16.47

The ASME B16.5 and ASME B16.47 flanges can be made from ASTM A182 Gr.F11 Class 2 steels by a forging process. They may be furnished in various flange types covering welding neck, slip on, and blind, etc. Both ASME B16.5 and ASME B16.47 have endorsed the use of ASTM A182 Gr. F11 Class 2 in Material Group 1.9, which has the nominal chemical composition of 1.25Cr-0.5Mo-Si. Flanges made from this steel are generally used with maximum working temperature limit of 590°C [1100°F]. It is permissible but not recommended for prolonged use above 590°C [1100°F].

Chemical Composition Requirements

Element	Composition, %
C	0.10-0.20
Mn	0.30-0.80
P	≤0.040
S	≤0.040
Si	0.50-1.00
Cr	1.00-1.50
Mo	0.44-0.65

*The UNS number of ASTM A182 Gr. F11 Cl. 2 is K11572.

Mechanical Properties

Tensile Strength min. ksi [MPa]	70 [485]
Yield Strength min. ksi [MPa]	40 [275]
Elongation in 2", min. %	20
Reduction of Area, min. %	30
Brinell Hardness HBW	143-207

*Tensile and hardness requirements.

Manufacture & Heat Treatment

The starting material of the ASTM A182 Gr. F11 Cl. 2 flange shall be low-alloy ferritic steels made by the open-hearth, electric-furnace, or basic-oxygen process with the option of separate degassing and refining processes in each case. The material shall be forged as close as practicable to the specified flange shape and size. After hot forging, the flange sahll be cooled to a temperature below 538°C [1000°F] prior to heat treating. ASME B16.5 or ASME B16.47 flanges made of ASTM A182 Gr. F11 Cl. 2 steels shall be furnished in normalizing and tempering condition only. The minimum austenitizing temperature is 900°C [1650°F]. The normalizing requires air cooling, which is followed by tempering with minimum tempering temperature of 620°C [1150°F].

Pressure-Temperature Ratings

Temp. °F	75# psig	150# psig	300# psig
-20~100	145	290	750
200	130	260	750
300	115	230	720
400	100	200	695
500	85	170	665
600	70	140	605
650	60	125	590
700	-	110	570
750	-	95	530
800	-	80	510
850	-	65	485
900	-	50	450
950	-	35	320
1000	-	20	215
1050	-	-	145
1100	-	-	95
1150	-	-	65
1200	-	-	40

*Pressure-Temperature ratings for ASTM A182 Gr. F11 Cl. 2 flanges of Class 75, 150 and 300; Values in “75#” column only applies to ASME B16.47 Series B Class 75 flanges; Values in columns “150#” and “300#” are applicable to both ASME B16.5 and B16.47 flanges of Class 150 and Class 300, respectively.

Temp. °F	400# psig	600# psig	900# psig
-20~100	1000	1500	2250
200	1000	1500	2250
300	965	1445	2165
400	925	1385	2080
500	885	1330	1995
600	805	1210	1815
650	785	1175	1765
700	755	1135	1705
750	710	1065	1595
800	675	1015	1525
850	650	975	1460
900	600	900	1350
950	425	640	955
1000	290	430	650
1050	190	290	430
1100	130	190	290
1150	85	130	195
1200	55	80	125

*Pressure-Temperature ratings for ASTM A182 Gr. F11 Cl. 2 flanges of Class 400, 600 and 900; applicable to both ASME B16.5 and B16.47 flanges.

Temp. °F	1500# psig	2500# psig
-20~100	3750	6250
200	3750	6250
300	3610	6015
400	3465	5775
500	3325	5540
600	3025	5040
650	2940	4905
700	2840	4730
750	2660	4430
800	2540	4230
850	2435	4060
900	2245	3745
950	1595	2655
1000	1080	1800
1050	720	1200
1100	480	800
1150	325	545
1200	205	345

*Pressure-Temperature ratings for ASTM A182 Gr. F11 Cl. 2 flanges of Class 1500 and 2500; applicable to ASME B16.5 flanges only.