Control valves
Pressure reducing/surplussing valves
F
E
F
D
4.6.21
Steam
saturation
curve
A
B
C
Body design conditions
Maximum design pressure
Maximum design temperature
Minimum design temperature
Pressure / temperature limits
PN40
40 bar g @ 50 °C
300 °C @ 25.8 bar g
90 °C @ 37.3 bar g
0 °C
300 °C @ 25.8 bar g
90 °C @ 37.3 bar g
Minimum operating temperature
Note: For lower operating temperatures consult Spirax Sarco
DN15 - DN50
25 bar
Maximum differential pressure
DN65 - DN100
20 bar
Designed for a maximum cold hydraulic test pressure of 60 bar g
Note: With internals fitted, test pressure must not exceed 40 bar g
DRV4
DRV4G
Pressure bar g
The product must not be used in this region.
A-C-D Flanged EN 1092 PN40 and ASME 300.
A-B-E Flanged ASME 150.
DRV4
Maximum operating temperature
DRV4G
0 °C
F-F
The DRV4G is limited to 90 °C.
No.
Part
1
Body
2
Bonnet
3
Valve seat
4
Seat gasket
5
Valve head
6
Valve head screw
7
Valve head seal
8
Bush
9
Bush (part of item 10)
10
Balancing bellows assembly
11
Balancing bellows gasket
12
Bonnet gasket
13
Bonnet nuts
14
Bonnet studs
15
Pillars
16
Pillars nuts
17
Spring adjuster
DN15
DN20 and DN25
DN32 to DN50
DRV4
DRV4G (soft seated)
DN15 and DN20
DN15 and DN20
DN25 to DN100
DN25 to DN100
DN25 to DN100
DN15 to DN40
DN50 and DN65
DN80 and DN100
Material
Cast steel
Cast steel
Stainless steel
Stainless steel
Mild steel
Reinforced exfoiliated graphite
GP 240 GH
DIN 17425 GS C25
BS 970 431 S29
BS 970 431 S29
BS 970 431 S29
BS 6105 A2
BS 970 431 S29
BS 970 431 S29
AISI 316 (L)
DIN 267 Pt13 Gr. 8
DIN 267 Pt13 Gr. 8.8
BS 970 230 M07
BS 3693 Gr. 8
DIN 1691 GG 25
Materials
Stainless steel
Stainless steel
Stainless steel
Arlon 1555
Stainless steel
Stainless steel
Stainless steel
/ Nitrile
M10
M12
M16
Reinforced exfoiliated graphite
Reinforced exfoiliated graphite
Steel
Steel
Steel zinc plated
Steel zinc plated
Cast iron zinc plated
For part numbers 18 to 46, please go to page 4
Page 2 of 10
TI-P203-01 CTLS Issue 17
DRV4 and DRV4G Cast Steel Pressure Reducing Valves
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