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Pump systems, pipes, valves and seals
⎪
Mechanical Technology — June 2015
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Extensive gear pump range for viscous fluids
T
he Viking range of internal gear
pumps continues to sell steadily into
South Africa through local distributor
Mather+Platt, which reports that carefully
maintained local stock holdings are helping
to secure urgent orders.
Wadeville-based Mather+Platt has
distributed Viking pumps for more than
20 years. Viking is widely recognised as
one of the world’s leading manufacturers
of positive displacement pumps such as
internal gear pumps, external gear pumps,
vane pumps and rotary lobe pumps. In
South Africa, these pumps are widely used
in mining and industrial applications, where
they transfer viscous fluids with viscosities
of up to 440 000 cSt.
The pumps have applications in petro-
chemical processing (bitumen, pitch and
viscous oils), chemical processing (sodium
silicate, acids, plastics, paints, resins,
adhesives and mixed chemicals), pulp
and paper (acids, soap, lime, kaolin and
sludge), and the food industry (chocolate,
butter, fillers, molasses and vegetable fats).
The internal gear pumping principle,
invented by Viking Pumps’ co-founder Jens
Nielsen, uses two rotating gears, which
un-mesh at the suction side of the pump
to create a vacuum, which pulls fluid into
the pump. The spaces between the gear
teeth transport the fluid on either side of a
crescent to the discharge side, where the
gears re-mesh to discharge the fluid.
Mather+Platt’s Viking range of gear
pumps is extensive, comprising six distinct
lines.
There are universal seal pumps in 12
sizes, comprising heavy duty, foot-mounted
models with enlarged bearing housings
that allow seals and seal technologies to
be exchanged without removing the pump
from the flow line. Materials of manufacture
include stainless steel, steel, ductile iron
and cast iron.
High-speed compact pumps in six sizes
are recommended for medium- to heavy-
duty applications. No speed reducer is
required and materials of manufacture are
as for universal seal pumps.
Motor speed pumps in six sizes are
manufactured in ductile iron, and may be
foot-mounted or close-coupled to IEC frame
motors for a compact footprint. General-
purpose foot-mounted pumps in 14 sizes
are made of cast iron for medium duty ap-
plications. Jacketing options are
available.
C-flange-mounted pumps in eight
sizes are made from cast iron for medium-
duty applications, and these do not require
speed reducers either.
For applications in which leakage and
fugitive emissions must be eliminated,
or where downtime for seal maintenance
would be problematic, there are mag-drive
pumps in 12 internal gear and 22 external
gear sizes, which replace shaft seals with
magnetic drives.
Mather+Platt can custom build Viking
pumps for special applications. Examples
include abrasive liquid pumps with hard-
ened construction and silicone carbide
seals, and ammonia pumps with double
mechanical seals, pressurised seal cham-
bers and oil reservoirs, lubricated idler
bushings, and adjustable return-to-tank
bypass valves.
q
Some of
the Viking
range gear
pumps.