Incoloy 825 flanges manufactured to ASME B16.5 can only be made from annealed material and its maximum applicable temperature is 538°C [1000°F]. It can be furnished in a variety of types including welding neck, slip on, blind, threaded, lap joint, long weld neck, and socket welding. The flange can be either made from ASTM B564 UNS N08825 forging or ASTM B424 Gr. N08825 plate(only for blind and plate flange) with nominal composition of 42Ni-21.5Cr-3Mo-2.3Cu.

Pressure-Temperature Ratings for Incoloy 825: Metric Unit

Temp. °C	Class 150	Class 300	Class 400	Class 600	Class 900	Class 1500	Class 2500
-29~38	20.0	51.7	68.9	103.4	155.1	258.6	430.9
50	19.5	51.7	68.9	103.4	155.1	258.6	430.9
100	17.7	51.5	68.7	103.0	154.6	257.6	429.4
150	15.8	50.3	66.8	100.3	150.6	250.8	418.2
200	13.8	48.3	64.5	96.7	145.0	241.7	402.8
250	12.1	46.3	61.7	92.7	139.0	231.8	386.2
300	10.2	42.9	57.0	85.7	128.6	214.4	357.1
325	9.3	41.4	55.0	82.6	124.0	206.6	344.3
350	8.4	40.3	53.6	80.4	120.7	201.1	335.3
375	7.4	38.9	51.6	77.6	116.5	194.1	323.2
400	6.5	36.5	48.9	73.3	109.8	183.1	304.9
425	5.5	35.2	46.5	70.0	105.1	175.1	291.6
450	4.6	33.7	45.1	67.7	101.4	169.0	281.8
475	3.7	31.7	42.3	63.4	95.1	158.2	263.9
500	2.8	28.2	37.6	56.5	84.7	140.9	235.0
538	1.4	25.2	33.4	50.0	75.2	125.5	208.9

*The table lists working pressures by classes at different temperatures, in bar unit.

Pressure-Temperature Ratings for Incoloy 825: US Customary Unit

Temp. °F	Class 150	Class 300	Class 400	Class 600	Class 900	Class 1500	Class 2500
-20~100	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	700	930	1395	2095	3490	5820
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	385	515	775	1160	1930	3220
1000	20	365	485	725	1090	1820	3030

*The table lists working pressures by classes at different temperatures, in psig unit.