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Progressive Cavity Pumps for accurate product metering
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SEEPEX Progressive Cavity Pumps for accurate product metering and control
Many industries need pumps to add small amounts of additives into process lines. These can include aggressive and corrosive chemicals in waste water treatment and in paper production, viscous products such as polymer for water treatment, abrasive lime slurries in sewage sludge treatment and valuable minor ingredients into beverage and food products. Although there are many different types of pumps used for metering, progressive cavity pumps offer many advantages over alternative positive displacement type pumps.To get more news about Progressive cavity pump part, you can visit brysonpump.com official website.
Further advantages of the progressive cavity pump is that the flow rates are minimally affected by changes in pressure or product viscosity, meaning that a wide range of products can be metered by the same pump design.
Products are subjected to a low shear action when compared to other positive displacement pumps and solids within the product are not crushed by the action of the pump, neither do they cause blockages within the pump.The action of pumping is the rotation of a single helical rotor inside a double internal helical stator which progresses a cavity of product through the pump; hence the name progressive cavity pump. This action produces more cavities per minute than a piston action associated with diaphragm pumps and is why pulsation is minimised. The virtual lack of pulsation means that a constant product stream is produced and a stable flow rate achieved up to +/-1% accuracy.
Because the rotor has a compression fit within the stator, both high and low viscosity products, even water, can be accurately metered, with no necessity for non-return valves. The constant dose and linear accuracy to +/- 0.5% of a progressive cavity pump means that calibration is simple. Ball valves and pulsation dampeners are not needed so vapour locking and sticking valves are eliminated.
The flow rate is directly proportional to pump speed so using a variable speed drive (VSD) means that flow rates can be varied and adjusted in real time using a closed loop feedback control system. Drive selection can offer a wide range of flow rates of a single pump with turndowns of 100:1 possible using VSDs.
Flow control valves are not needed either as the constant action provides flow control in real time without the need for sampling or averaging commonly needed on piston diaphragm pumps.
Other advantages of the progressive cavity pump are that the flow rates are minimally affected by changes in pressure or product viscosity thus a wide range of products can be metered by the same pump design. Products are subjected to a low shear action when compared to other positive displacement pumps and solids within the product are not crushed by the action of the pump.
Progressive cavity pumps can also be installed in a variety of flexible configurations including vertically where space may be an issue. A single pc pump can replace a system which may need flow control, pulsation dampeners and non return valves in addition to a pump so capital costs can be reduced.One example of this is the use in SEEPEX ferric compounds in the waste water treatment industry. Iron compounds are commonly used within the waste water treatment and anaerobic digestion processes to reduce phosphate content in settled sludge, reduce hydrogen sulphide content in biogas and sometimes to augment flocculation.