Click here to enlarge imageThe positive displacement pumps use efficient roller technology that eliminates the cumbersome lubrication fluid typical of peristaltic pumps using a sliding-shoe design. In addition, there are no valves, no seats and no seals required in the pumped fluid to foul or wear out.
For maximum versatility in municipal and industrial applications, there are eight different pump models available with tube sizes ranging from 10 mm to 76 mm diameter. Flow rates from 2 to 14,500 gph are available at pressures up to 225 psi. A choice of constant speed, mechanical variable speed or variable frequency variable speed drives is available for simple manual operation or automatic control schemes.
The Chemtube PPS is suitable for virtually any chemical used in the water and wastewater treatment process. It is suitable for either continuous or intermittent metering of even the most difficult to feed chemicals, including sodium hypochlorite, which has a tendency to out-gas and "air-bind" some metering pumps.
The pumps can also be used for supplying water/wastewater samples to on-line analytical equipment or for transfer of chemicals from bulk supplies to day tanks and process tanks. Optional wheels provide for moving the pump to various transfer sites. The pumps may also be used for delivering a variety of sludge, including those with high solids content, to de-watering equipment.
The Chemtube PPS uses a rotating heavy roller design for squeezing the hose within the pump housing. The S and M series of pumps use two rollers, while the higher capacity L series pump uses three.
No lubrication fluid is required: the smooth, rolling action of the roller creates much less friction against the tube than a sliding shoe design. This eliminates the requirement for lubrication inside the pump housing. Since no lubrication is required, the hose can be replaced without having to drain and dispose of lubricants.
Every Chemtube PPS is equipped with a leak detector to provide early indication of hose failure. The detector is a float type sensor located at the lowest point of the pump housing. Should the hose begin to fail and weep chemical into the pump housing, an alarm contact is initiated.
Most models use a direct coupled, right angled gearbox to provide the smallest footprint possible.
The capacity of the Chemtube PPS is controlled by the speed of the pump rotor. There are a variety of speed control options:
- Constant Speed - This is the basic drive featuring a constant speed AC motor.
- Mechanical Variable Speed - An optional mechanical variable speed gearbox is available providing a manual 5.5:1 turndown ratio.
- Variable Frequency Drive - This uses an AC inverter motor and a VFD for turndown ratios up to 10:1. The speed is manually adjusted at the VFD or it can be automatically controlled from a flow signal or a process signal.
