Batescrew Axial Flow Pumps.
Overview

Batescrew manufacture axial flow and mixed flow turbine pumps.  Both types are in fact 'axial flow' and of fairly similar external appearance.
Our designated Axial Flow type is best suited to high volume pumping, at low to medium heads, while Turbines will pump to higher heads with greater efficiency. 
Lower initial cost of the Axial Flow type is due largely to less intricate castings required in the ‘wet end’ of the pump.

Overview Topics  
Click these headings to see overview notes.
For more detail, click the links within the overview text. 

Applications
Pump Sizes
Head & Flow Charts
Angle Application Pumps
Vertical Application Pumps
Columnless Pumps
Oil or Water Lubrication
Speed Reduction
Fuel Costs
System Requirements   
Construction Materials

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:  DescriptionDrive OptionsDimensions;  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: 
DescriptionDrive OptionsDimensions;  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.