Rotapump surface-mounted groundwater monitoring and well development pump

Description

ROTAPUMP  MODEL 100
The Rotapump Model 100 is a wellhead pump that easily pumps 2-inch monitoring wells from any depth.  The pump is easily transported, setup, and operated using a portable drill or electric motor powered by a car battery.  Decontamination of equipment between wells is eliminated because the pump uses a dedicated pumping tube stored in each well.  The pump is self priming from any depth and can pump sediment laden water with no  difficulty.  The pumping rate can be precisely controlled at a constant rate from 1/4 gpm up to 6 gpm or more.  Sediment-free low-flow purging and sampling are easily done by placing the pumping tube inside a stilling tube.
The pump has an elliptical plate mounted on a rotating shaft.  As the shaft rotates the edge of the plate moves up and down.  This up and done motion is transferred to a follower with rollers bearing on the top and bottom of the plate.  The follower is constrained to move only vertically by rollers attached to each side of the follower that bear on vertical rods.  A pumping tube with a bottom check valve is attached the follower with hose clamps so that with each revolution of the plate the pumping tube move up and down once.  On the down stroke, the bottom check valve opens due to water resistance and admits water into the pumping tube.  On the upstroke the pumping tube is lifted and the check valve closes due water pressure.  Water is incrementally added to the pump tube and once the tube is full, water is discharged from the tube and well.  At high RPM, the rapid lifting of the pumping tube on the upstroke imparts upward momentum to the water in the tube.  On the rapid reversal of direction on the downstroke, the momentum causes water to continue to flow upward and draw additional water in the tube through the bottom check valve.
Briefly stated, the pump mechanism action converts horizontal rotary motion into cyclic up-and-down motion, the vertical motion is imparted to a pumping tube having a bottom check valve, and the cyclic up-and-down motion jacks water up then out of the pumping tube.  The faster the up-and-down motion the greater the flow rate.
Pump parts are primarily stainless steel, aluminum, and Teflon/Delrin.  All shaft and roller bearings are sealed.  The pump does not require lubrication and is easily disassembled.  Load bearing materials in contact are aluminum or steel and Telflon/Delrin.  This combination of materials results in negligible wear of mated bearing surfaces.
A drill harness is offered for operation of the pump using a portable drill.  A speed controller placed between the drill and 12 volt battery is offered for precise control of the flow rate.
A 450 Watt DC motor that mounts securely on the pump is also available. The motor is designed for use with the speed controller.  The pump is most easily used with the 450 Watt motor and speed controller and is the recommended style of use.
Visit Rotapump.com for more information and videos of operation.
Please call 707/354-4618 to discuss your sampling requirements.