12.1.3 Isolation and drain valves
Isolation and drain valves must be installed in the fluid path. This is necessary for the following reasons.
l
The pumphead replacement procedure requires the fluid path to be isolated, and parts of the fluid path
drained prior to being disconnected.
l
Other procedures require the pump to be removed from service, such as due to a fault. This will require
the isolation and draining of parts of the fluid path
l
Prevent unintentional flow when the pump is stopped and in the event of any of the following:
l
Leaks from the pumphead or fluid path
l
Pumphead or fluid path failure
l
Wear of the pumphead components
Valves must be opened before the pump starts and closed after the pump has stopped.
Do not fit valve on drain port of pumphead.
12.1.4 Inlet and discharge pipework
Inlet
and
discharge
pipes should:
l
Be as short as possible
l
Be as direct as possible
l
Follow the straightest route
l
Use bends of large radius
With the largest diameter bore tube that will fit with your process.
12.1.5 Piping vibration
A Piping Vibration and Integrity Assessment (piping vibration audit) of the qdos pump installation should be
undertaken.
12 INSTALLATION: PART 3 (FLUID PATH)
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