Seepex BN 5-12 Series, Operation & Maintenance Manual

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7
The diversity of customer requirements demand made-to-order
solutions. Which is why we will supply the correct rotor/stator
geometry – whatever the application. The right geometry is
selected on the basis of the conveying capacity, the pressure
and the substance being transported. It’s the only way to get
optimum performance from your pump.
Conventional geometry is a standard design that has proven
its worth over decades. It consists of a single-helix rotor with
a short pitch and the corresponding double internal helix stator.
Apart from the various characteristics that make it suitable
for almost every application, this design really performs best
when conveying highly viscous liquids or applications with low
NPSHA. Pumps with conventional geometry can be delivered
rated for pressures of up to 48 bar (720 PSI) as standard.
In comparison with the conventional geometry, 6L geometry
has a smaller rotor diameter and a longer pitch. The resulting
advantages in terms of efficiency and wear are especially use-
ful for conveying more fluid substances. As indicated by the
name, 6L geometries can be deployed with a counter pressure
of up to 6 bar (90 PSI).
The Tricam geometry, with its single stage (6LT) design, is a
logical further development from the 6L geometry. The use of
a double external helix rotor in an internal three-helix stator
increases the conveying capacity by 50 % in a pump with the
same outer diameter and length.
Even at higher pressure requirements (up to 36 bar or 540 PSI),
the Tricam design increases conveying capacity by 50 % com-
pared to the conventional or 6L geometries.
Stators with uniform elastomer wall thickness are character -
ized in particular by a higher stage pressure. Instead of 6 bar
(90 PSI) per stage, up to 12 bar (180 PSI) is allowed with
this design. These stators can also be usefully deployed for
high-temperature media.
An overview of the rotor/stator geometries.
Conventional geometry, multi-stage
6L geometry, single stage
Tricam geometry (-6LT), single stage
Tricam geometry (T), multi-stage
Conventional geometry,
stator with uniform wall thickness