| Batescrew
turbines are of conventional 'mixed flow turbine' design, in which energy is
imparted to the flow by impellers utilizing the dual components of
centrifugal force and vane reaction, an efficient arrangement for pumping
at medium to high heads.
PRESSURE OUTPUT
Delivery pressure is increased by adding multiple impeller stages to a
pump, with each extra stage proportionately increasing pressure output and power
consumption.
Adding impeller stages does not increase flow rate.
The maximum pressure achievable depends on the number of stages which may
be safely added to each pump model.
The maximum number of stages (therefore maximum pressure) is stated on the
data sheet 'Impeller
Performance Curve' for each pump model. See... Performance Curves
FLOW RATE
Capacity of pumps in the Batescrew Turbine range varies from
5 litres/second to 1600 litres/second.
The output of any pump may be varied, within limits, by changing rotational
speed, in which case impeller performance curves should be consulted to ensure
performance will remain within an acceptable efficiency range.
See... Performance Curves
VERTICAL and ANGLE APPLICATIONS
These pumps may be used vertically, as bore pumps, or in angle
applications on river banks and storage dams.
See... Vertical
Application Angle
Application
DRIVE OPTIONS
For illustrations of various electric and diesel drives:
See... Drives Vertical
Drives
Angle
LINE SHAFT LUBRICATION
These pumps are generally line shaft driven, with bearings
lubricated either by 1) Water; 2) Oil; or 3) Fresh Water Flush.
1) OIL LUBRICATION extends bearing life and is used when grit or
suspended solids are to be pumped.
Lubricant is a bio-degradable vegetable oil,
drip-fed to an enclosed shaft running in bronze bearings. The
enclosing lube-tube is galvanized externally and internally to protect
lubricant from contamination by products of condensate corrosion.
Adjustable drip feeders are fitted as standard. Solenoid drippers
are used with automatic-start systems to enable lubrication to begin
fifteen minutes before pump start.
2) WATER LUBRICATION is an option if the supply is sand-free potable
water. The pumped medium lubricates an exposed stainless steel line
shaft, running in EPDM rubber bearings. (Batescrew petrol pumps use a
similarly product-lubricated system with synthetic bearings.)
3) ENVIRONMENTALLY SENSITIVE LUBRICATION
(Fresh Water Flush)
This Batescrew developed system prevents contamination of natural waterways by lubricating oil,
even though this oil may be bio-degradable.
When water quality is unsuitable for lubrication and would normally
dictate use of oil, the alternative of Fresh Water Flush provides clean lubricating water to stainless shafts
running in EPDM rubber bearings, all enclosed in
a sealed lube-tube.
Two variations are in use:
a) When the pumped water is non-aggressive, but contains suspended
solids, filtered water is fed from the pump discharge to the line shaft bearings.
b) When the pumped water is highly acidic, alkaline, or otherwise
aggressive, clean fresh lubricating water is supplied from an independent reservoir.
In both cases, provision is made for lubricating water to be
available at the bearings before the pump is started.
MORE BEARINGS per
PUMP
Spacing between line shaft bearings on Batescrew pumps is restricted to a
maximum of 1.22 metres.
Close bearing spacing ensures
design stress of drive shafts is in compliance with 'Fixed Fire Pump Standard
AS2941'.
As a result, our pumps may have more line shaft bearings than are found
in pumps from other manufacturers.
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