Endress+Hauser Flowfit CYA27, Руководство по эксплуатации

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Maintenance Flowfit CYA27
34 Hauser
9.2 Maintenance tasks
9.2.1 Decommissioning
L
CAUTION
Compressed media
Risk of injury from high pressure, high temperature or chemical hazards if process medium
escapes.
‣
Wear personal protective equipment consisting of protective gloves, goggles and
protective clothing.
‣
Perform maintenance or repair work on the assembly only when it is depressurized,
has cooled down and has been rinsed.
L
CAUTION
Incorrect operating sequence of valves during decommissioning
This may lead to increased pressure in the assembly and may impair or completely disrupt
the functioning of the sensors (loss of calibration). This may in turn cause further harm (to
other plant components, dosing system personnel).
‣
Follow the operating sequence in accordance with the switch-off sequence.
‣
Instruct operating personnel regularly and, if necessary, attach a notice to the
measuring point.
Switch-off sequence
To switch off or stop the flow at the measuring point, proceed as follows:
1. Close valve at inlet.
2. Close valve at outlet.
3. Carefully open the sampling valve or loosen a sensor to relieve pressure in the
assembly.
If the measuring point is temporarily shut down and the sensors are to remain in the
assembly, ensure that sufficient medium (water) is present in the assembly and the
sensors do not dry out. Keep the valves at the inlet and outlet of the assembly closed
for this purpose.
9.2.2 Draining
Take the assembly out of operation prior to draining (→  34).
Draining can be performed safely at different locations or in different ways:
At the installation site:
1. Open the sampling valve.
2. Open the sensor slot or the outlet connection, whichever is positioned further away
from the valve.
 The process medium drains off through the sampling valve.
3. Collect process medium at the sampling valve.
Or:
The negative pressure effect can be used for outlet lines that have an open end and a
downward slope.
1. Open the outlet valve.