UK Product Handbook 2026 - Volume 1

Control systems Pressure reducing/surplussing valves

4

Pressure/temperature limits

B

C

A

Steam saturation curve

F

F

E

D

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.

F-F The DRV4G is limited to 90 °C.

Body design conditions

PN40

Maximum design pressure

40 bar g @ 50 °C

DRV4

300 °C @ 25.8 bar g

Maximum design temperature

4.6 37

DRV4G

90 °C @ 37.3 bar g

Minimum design temperature

0 °C

DRV4

300 °C @ 25.8 bar g

Maximum operating temperature

DRV4G

90 °C @ 37.3 bar g

Minimum operating temperature Note: For lower operating temperatures consult Spirax Sarco

0 °C

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

TI-P203-01 CTLS Issue 20

Page 3 of 15

DRV4 and DRV4G Cast Steel Pressure Reducing Valves

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