The pump industry relies on expertise from a large and varied range of specialists, from experts in particular pump types to those with an intimate understanding of pump reliability; and from researchers who delve into the particulars of pump curves to experts in pump efficiency. To draw upon the wealth of expert knowledge the Australian pump industry has to offer, Pump Industry has established a panel of experts to answer all your pumping questions.
Progressive cavity pumps
Our progressive cavity pump expert is Peter Vila, Managing Director of SEEPEX Australia. Peter has been involved with pumps for 35 years. He spent the first five years repairing them and the subsequent 30 years directly in technical sales, and for the past 15 years he has been predominately involved with SEEPEX progressive cavity pumps.
We often hear that progressive cavity pumps are of the positive displacement variety. Does this mean they are well-suited to dosing and metering applications?
Most certainly yes. Progressive cavity style metering pumps have highly repeatable accuracy. They can be used in virtually all industries for metering and dosing precise quantities. They are particularly good for minimal pulsation conveying of thin to high viscosity fluids, as well as corrosive media containing solids, all with minimal pulsation and to the exact drop.
Progressive cavity metering pumps can be used for applications in agriculture, automotive assembly, bakeries, building products, ceramics, chemical and biochemical processing, coating kitchens, stock preparation and de- inking in paper mills, confectioneries, dairies, distilleries, dye and ink plants, fruit and vegetable processing, pharmaceuticals, cosmetics and personal care products, poultry, meat and fish processing, oil, gas and petrochemicals, shipbuilding, sewage sludge dewatering, wastewater treatment, water purification, wineries, wood treatment and fabrication.
Typical progressive cavity metering pump
Popular features:
- Simple interchangeability due to modular construction
- Infinite turndown
- Minimal pulsation, no pulsation dampers required
- Constant flow, independent of pressure
- Low shear characteristics
- High metering accuracy
- Valveless flow control
- No check valves, no gas locking or blocking by solids
- Drive options and control systems available that allow user-friendly metering applications.
Performance range:
- Conveying capacity: 0.06 l/h–1,000 l/h (0.016–264 USGPH)
- Pressure: up to 24bar (360psi)
Progressive cavity metering pump with an integrated programmable drive
Common applications:
Filler Feeding
Volumetric fillers such as those used in the food industry to fill bottles, cans or cups have tanks above piston-
actuated filling devices. The levels in the tank need to be maintained and are usually measured with capacitance probes that output a 420 mA signal. In combination with a programmable integrated drive, PC pumps can be used to maintain a proper level in the supply tank, without requiring a separate controller or electrical panel.
Sodium hypochlorite (NaOCl) can be reliably injected into the discharge of a vertical turbine pump, in a water well, to increase the chlorine contact time for more positive disinfection.
PC pumps with a programmable integrated drive can follow the signal from a flow meter, on the discharge of the centrifugal pump, to maintain the proper dosage in ppm of chlorine.
Extruders are commonly used to form a variety of shapes in the manufacturing of breakfast cereals, dry pet food and certain snack products.
PC pumps with a programmable integrated drive can be used in conjunction with a PLC to inject liquids or dyes and change the colour of these products continuously, without a system shutdown. They can also be used to inject vitamins, oils, syrups or other liquids.
By using two PC pumps with an integrated programmable drive, the pH of a process or waste stream can be controlled.
A standard program is used and the pumps are controlled by a PLC that defines one pump handling alkaline to increase its speed as the pH drops, or the other pump handling an acid to increase its speed as the pH climbs. By using PC pumps with an integrated programmable drive, users can significantly reduce the installation time and cost because they do not need remote panels.
Other applications:
- Boundary layer injection
- Multiple component blending
- Extruder injection of colours, vitamins or minerals
- Release agents, creping agents, colours and other paper chemicals
- High fructose corn syrup
- Alpha and beta amylase in corn processing
- Any enzyme
- Liquid fertilisers or herbicides into a centre pivot irrigation system
- Scents and flavours into any food product, even tobacco
- Filter aids like diatomaceous earth for cold filtered beer
- Polymer flocculants and ferric chloride
- Water treatment chemicals of any type
- Spray applications like spray dryers or flavoured coatings for snack foods because of the non-pulsating flow.
For more information on progressive cavity pumps, contact SEEPEX Australia on (02) 4355 4500 or [email protected].