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Applications.
In agriculture these pumps are used for irrigation, tail water control and
on-farm storage schemes. They are used by Local Government and Semi-Government
Authorities, for flood mitigation, town water supply, wastewater and
environmental control projects. There
are many other applications, from marine bow-thrusters to prawn farms.
Batescrew 'Portax' portable pumps are part of the axial flow range.
Pump Sizes.
Nineteen sizes are
manufactured, pumping from 2 to 280 megalitres per day, to total dynamic
heads of up to 28 metres per stage.
Sizes are indicated by a two-part model number e.g. 14/16, indicating
nominal diameters of impeller/column, in inches.
Models available are: 4/4; 5/6; 7/7; 7/9; 9/9; 9/11; 11/11;
11/14; 14/14; 14/16; 17/18; 17/21; 21/21; 21/24; 24/24; 24/30; 23/36;
32/42; 32/48.
Head & Flow Charts.
The performance graphs (see Capacity Selection.)
show both Head and Flow for each pump. Some overlapping occurs,
where two models are capable of achieving the same head/flow. In
such cases the smaller pump will cost less while the larger will normally
have lower running and maintenance costs.
Note: Multiple impeller stages added to a pump will directly
multiply the Head achieved and power required, but will have no
appreciable effect on Flow Rate.
Our Technical Services department will assist in selecting a suitable pump
or pumps for an application (see Design Calculations).
Pump Configuration.
As illustrated on the previous page and described below, Batescrew axial
flow pumps are made in three configurations, to suit site conditions and
installed cost considerations.
1) Angle Application pumps
are used for riverbank and storage
dam installations. For river
use they offer the least obstruction to river flow, less bank disturbance
and require less infrastructure than vertical pumps.
The flanged discharge outlet is inclined at an angle of 36 degrees to the
main axis of the pump. Discharge
may be either above or below ground. In the latter case an extended drive column may be fitted,
keeping the power unit and pump thrust bearings above possible flood
level.
See also: Description; Drive
Options; Dimensions; System
Requirements.
2) Vertical Application pumps,
for non-river use, are
simple to install and will cost less than angle pumps.
When the depth of an excavation exceeds six metres, costs become
excessive and an angle application pump should be considered.
Split mounting plates
allow a vertical pump to be rotated, in one hole increments of the base
flange, to align the discharge outlet as required.
Mounting plates are normally located immediately below the
discharge head or, for below-ground discharge, may be located immediately
above the head or at the top of an extended drive column.
Please indicate the preferred location of mounting plates when
ordering.
See also: Description; Drive
Options; Dimensions; System
Requirements.
3)
Columnless pumps are the lowest cost version, used in wells or
pre-fabricated structures.
The cost of discharge Column and Head is avoided, although
cost of the well or sump may be higher. A sliding non-return valve may be
fitted to the drive shaft column, to seal on the upper flange of the pump
body. Further details re. drive options, system requirements etc.
are the same as for Vertical Application pumps at (2) above.
Oil or Water Lubrication.
Pump shafts may be oil or water lubricated, depending on water quality and
customer preference (see Lubrication Options).
Speed Reduction.
In some cases it will be necessary to match the optimum
operating speed of a power unit, with the necessary RPM of a pump shaft. For diesel engines this may be achieved by twisted vee-belts,
or by an angle gearbox of the required ratio, connected to the engine
by universal shaft. .
Crossed belts may be used, up to a maximum of six belts or 45 kW (60 hp).
For electric motors, reduction may be achieved mechanically by vee-belts
or angle gearboxes, or may be achieved electrically by a Variable Speed
Drive unit. The latter option
allows for the use of direct-coupled motors, avoiding belts, gearboxes and
universal shafts.
See also: Drive Options for angle
application pumps;
Drive Options for vertical application pumps.
Fuel Costs.
Fuel costs can be calculated for any proposed installation, based on pump
size, choice of impeller, system layout, required head & flow
rate and the on-site cost of fuel. This calculation is normally
done, as a free service, by the Batescrew Technical Services
department. Calculations are made for both diesel and electric
drives, to assist in drive selection.
See Design Calculation Service.
System Requirements.
For a pumping installation to be efficient, certain fundamentals (e.g. the
effect of sump design on pump intake losses) must comply with
well-established guidelines. The essentials are shown diagrammatically
in:
System Requirements for angle application
pumps;
System Requirements for vertical application
pumps.
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