Control valves

Desuperheaters

How to order

Please send the following process data to Spirax Sarco so that we can select the optimum solution for your application.

Minimum information required to size the desuperheater:

-

Maximum and minimum superheated steam condition (Pressure, temperature and flowrate).

-

Required outlet steam temperature.

-

Available water condition (Pressure and temperature).

Minimum

Nominal Maximum

Pressure

Superheated steam

Temperature

Flow

Steam outlet

Temperature

Water

Pressure

Temperature

Please state if you

require any of the

Additional information

following, the number(s)

required and

nomenclature if known:

Positioner(s)

Air regulator(s) Limit switch(s)

Further information, that if supplied, will help in selecting the optimal solution for your application:

Design pressure

Design temperature

Superheated steam size

Required flanged desuperheaters flange

Required flanged water flange

Fail safe position - Specify either Open or Closed

Selection chart

Turndown 1:1

2:1

3:1

4:1

VAD: Variable desuperheater

Minimum water pressure : Steam + 3 bar

Kv table

5:1

7:1

10:1

30:1

T

SAT

+ 5 °C

50:1

Desuperheater VAD a VAD b

Travel

30 mm 70 mm

Rangeability

1:20 1:40

Maximum turndown

50:1 50:1

Kv standard

1.40 4.0

1.00 3.7

0.60 3.3

0.54 2.9

0.45 2.5

0.40 2.1

0.20 1.8

0.10

Note: For lower or higher Kv please contact Spirax Sarco

TI-P451-01 CH Issue 3

Page 7 of 7

VAD Variable Area Desuperheaters

4.8.30