Birkett Technical Catalogue - Safety Systems UK Ltd

VALVE SELECTION TABLE
L
– 2.853 in 2
– 1840 mm 2
Flanges ANSI
Key Valve size
No. inlet x outlet Inlet Outlet Body
(ins)
Mat’l
-76°F
to
-450°F
-60°C
to
-268°C
Max. Set Pressure (psig)
and Temperature Limits
-21°F
to
-75°F
-30°C
to
-59°C
100°F
to
-20°F
38°C
to
-29°C
450°F 800°F 1000°F
232°C 427°C 538°C
Max. Back
Pressure
(psig)
Conventional
Valve
Balanced
Bellows Valve
1 3 x 4 150#RF 150#RF - - 285 185 80 - 285 100
2 3 x 4 300#RF 150#RF - - 285 285 285 - 285 100
3 4 x 6 300#RF 150#RF
WCB
- - 740 615 410 - 285 170
4 4 x 6 600#RF 150#RF - - 1000 1000 825 - 285 170
5 4 x 6 900#RF 150#RF - - 1500 1500 1235 - 285 170
6 4 x 6 1500#RF 150#RF - - 1500 1500 1500 - 285 170
7 4 x 6 300#RF 150#RF - - - - 510 225 285 170
8 4 x 6 600#RF 150#RF
WC6
- - - - 1000 445 285 170
9 4 x 6 900#RF 150#RF - - - - 1500 670 285 170
10 4 x 6 1500#RF 150#RF - - - - 1500 1115 285 170
11 3 x 4 150#RF 150#RF 275 275 - - - - 275 100
12 3 x 4 300#RF 150#RF 275 275 - - - - 275 100
13 4 x 6 300#RF 150#RF CF8M 535 720 - - - - 275 170
14 4 x 6 600#RF 150#RF 535 1000 - - - - 275 170
15 4 x 6 900#RF 150#RF 700 1500 - - - - 275 170
RF=Raised Face
Minimum set pressure limits for metal seat trim
Conventional – 5 psig
Bellows - Gas – 13 psig
Bellows - Liquid – 23 psig*
Conventional – 1.5 psig
(Inverted)
*For liquid bellows valves below this pressure refer to factory
Note: Soft seated valves require a minimum set pressure of 15 psig.
High Pressure Version.
Certain spring materials cannot be used in the low pressure version of the valve, up to the maximum
pressure. If the required set pressure with your choice of spring material is in excess of the figure shown in
the table either choose another material or add “H” to the valve accessories to select an high pressure valve.
Inlet Max. Set Spring Material (pressures in Psig)
Orifice rating Pressure Psig Carbon st. 316 SS Tungsten 17/4PH 17/4PH NACE Inconel X750
3L 150# 285 n/a n/a n/a n/a 255 n/a
3L 300# 285 n/a n/a n/a n/a 255 n/a
4L 300# 740 n/a n/a n/a n/a n/a n/a
4L 600# 1000 n/a 850 n/a n/a 825 n/a
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