Einbau- und Betriebsanleitung
Installation and Operating instructions
Instructions de montage et de service
5751-8010
19
07/2013
5.4
Pneumatic connection
Connect according to operating instructions of actuator.
Provide every valve with a separate pressure regulator to ensure constant incoming air pressure.
Attention!
Only use clean, dry and oil-free instrument air according to ISO 8573-1!
(Not lubricated, pressure dew point 20 K below lowest ambient temperature, solids content < 30µm)
5.5
Configuration of sensors and limiters for temperature
Temperature sensor Pt100 preferably fast-acting version. (See data sheet 1100-7010 e.g. WT1102)
Position temperature sensor Pt100 in the piping only after the evaporation process has been completed, i.e. at the earliest 7 m downstream
from the desuperheater, better still 8-12 m.
For problematic temperature measurements connect four Pt100 to create one Pt100 (two each in series and both pairs parallel) and install
these staggered at 1-metre intervals and distributed on the circumference of the pipeline.
Position one each STB and SDB close to the temperature sensor or pressure transducer in the piping.
6
Commissioning
Commissioning may only take place once the points in Chapter "
2 Installation and connection”
have been completed.
The steam converting valves are already adjusted and a function testing performed by the manufacturer. An adjustment of the
actuators is therefore not necessary.
6.1
Start-up
Ensure that all components are installed correctly. Connection of the electrical supplies and instrument air piping should be in
accordance with the manufacturer’s instruction manual.
In case of pneumatic actuator, check for any air leakage in the joints using soap solution.
Verify and adjust, if necessary, set points for filter regulators and valve positioners, following the manufacturer’s recommendations.
Similarly, calibrate the temperature transmitter/controller & positioner, verifying automatic response to temperature changes.
Charge the main stream line and open the valve in the water spray line. Check the water pressure at the Desuperheater. Verify the
operation of the temperature transmitter and controller by manually increasing and decreasing the output signal and observing
indicated and recorded temperatures.
Calibrate the system components including positioner, pressure and temperature sensors and after satisfactory performance change
to automatic mode. In case of problem listed below, please take appropriate measures as suggested
Maximum flow rate is not achieved:
Check whether the valve is 100% open.
Check that all manual shut off valves are open and the dirt traps are clean
Compare the dimensioning data with the actual operating data.
Valve is working with small stroke:
The valve should be adjusted to the actual operating data to avoid premature wear of the control
fitting.
Coordinate measures with the manufacturer.
Steam temperature is too high:
Check whether cooling water pressure is available in designated amount and that all manual shut
off valves are open and the dirt traps are clean.
