Maximum pressure ratings for flanges and material specification AST-A-105.

Gauge Pressure (kPa)
Temperature (oC)	Flanges Classes 150 - 2500
	150	300	400	600	900	1500	2500
< 38	1900	4960	6610	9920	14900	24830	41380
50	1830	4940	6560	9850	14840	24670	41130
100	1630	4800	6400	9600	14450	24020	40060
150	1450	4680	6260	9400	14130	23500	39200
200	1260	4600	6150	9190	13850	23060	38380
250	1070	4370	5850	8780	13170	21920	36600
300	940	3960	5300	7900	11900	19810	33060
350	810	3480	4670	6930	10490	17440	29000
375	750	3210	4340	6380	9660	15800	26770
400	690	2910	3940	5820	8780	14580	24360
425	640	2550	3440	5100	7730	12820	21250
450	580	2140	2880	4270	6460	10760	17820
475	510	1680	2240	3340	5070	8420	14030
500	400	1240	1620	2460	3720	6170	10330
525	340	810	1080	1600	2410	4030	6720
538	260	550	760	1100	1650	2820	4590