Pumps With Quench - Packo AX Instruction Manual

4.7. Pumps with quench

In In a pump with quench the sealing faces of the
mechanical seal are lubricated and/ or cooled by
a liquid other than the pumped liquid. This lubri-
cating liquid is supplied to and from the pump
via the two connections in the quench chamber.
There are four different types of quench (indi-
cated by the fourth from last letter in the pump
code on the nameplate of the pump. For a pump
without quench this letter is "S", e.g. S33KEN):
• Q, or B: quench chamber sealed by a lip seal;
• D or C: pressure less double mechanical seal;
• P: double mechanical seal with pressurized
barrier;
• I, J or K: flushed mechanical seal with forced
circulation of the flushing liquid
In case of doubt about the type of quench on the
pump, please contact PACKO.
The connection of the types Q, B, D & C is the
same and can be done as follows in 2 ways:
For pumps that have to lift the liquid from a well,
installation of a suction vessel is needed. This
suction vessel has to retain at least 4,5L liquid
for pump types 32-125, 40-125, 40-160, 32-185
and 40-185 and 6L for all other types. A suction
vessel can be made as indicated on the drawing
beside. In order to retain 4,5L or 6L, the ves-
sel has to be a lot larger. For retaining 4,5L the
suction vessel can have a diameter D of 200mm
and a length L of 350mm. For retaining 6L, the
vessel should be at least 525mm long with a
diameter of 200mm.
(Fig. 1) l.e., the throttle, supplied with the pump,
is fitted to the bottom connection and connected
to the water supply. The flow is set so that a small
amount of water drips from the upper side (± 10
l/hour). It is preferable to fit a hose at the upper
connection so that any leakage can be sent to
drain. Never put a valve or restriction in the drain
side of the quench liquid or pressure may build
up in the quench chamber.
(Fig. 2) Alternatively, disregard the throttle and
connect the quench chamber to a quench reser-
voir of at least 5 litres. To ensure sufficient circu-
lation of the quench liquid its viscosity must be
less than 100 centiPoise. The hoses must have
an internal diameter of at least 14 millimeter and
must be less than 2 metres long in total. The hoses
must be arranged so that no air traps occur which
will prevent circulation. The reservoir should be
approximately 70 centimeter above the pump, both
hoses must connect to the reservoir below the
liquid level. The liquid level in the reservoir should
be regularly checked and topped up accordingly
Fig. 1
and the hoses checked to ensure good circulation.
Fig. 2
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