The supply of the mechanical seal with sealing fluid must be pressurised. The
sealing pressure should be at least 1.5-2.0 bar (22-29 psi) above the maximum
internal pressure of the pump. Max. internal pressure = system pr
pumping pressure at Q = zero. Obtain the delivery head at Q=0 from the test
bench acceptance of your pump.
When operating with a frequency converter, consider the varying delivery heads.
When using a closed sealing circuit with a supply reservoir, regularly monitor the
fill level (visually or by means of level probes). Change the sealing fluid regularly
when using critical media.
The maximum temperature of the flushing fluid must be 20 K below the boiling
temperature of the flushing fluid at the outlet. The temperature rise in the pump
flushing chamber is normally less than 10 K (inlet/outlet). The maximum
permissible operating temperatures of the flushing device must not be exceeded.
Double mechanical seal - tandem arrangement (optional)
Flushing fluid
To maintain their function, mechanical seals need a flushing fluid, which has the
following tasks, including others:
•
Dissipation of any leakage
•
Protection against dry running
•
Lubrication and cooling of the mechanical seals
A clean liquid, compatible with the pumped fluid, is used as the flushing medium.
Ensuring the flushing operation
1.
Open the inlet of flushing fluid.
2.
Vent the seal cartridge.
3.
Ensure pressureless circulation.
→ Done.
For abrasive media, use lost flushing in which the flushing fluid is discharged
directly.
Permissible supply pressures and temperatures
The supply of the mechanical seal with flushing fluid must be unpressurised. The
maximum overpressure may not exceed 0.2 bar (2.9 psi). When using a pass-
through flushing, secure the flushing fluid connection with a pressure reducer or
similar if necessary.
When using a closed flushing circuit with a supply reservoir, regularly monitor the
fill level (visually or by means of level probes). Also, make sure that no pressure
build-up can occur in the flushing circuit. Keep the reservoir open to the
atmosphere. Change the flushing fluid regularly when using critical media.
The maximum temperature of the flushing fluid must be 20 K below the boiling
temperature of the flushing fluid at the outlet. The temperature rise in the pump
flushing chamber is normally less than 10 K (inlet/outlet). The maximum
permissible operating temperatures of the flushing device must not be exceeded.
Assembly and installation
Setup, installation, and connection
BA.H2A.ADY.002.GB_1
18.12.2017
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