Thompson’s piston wellpoint dewatering pump is highly efficient. It produces a pulsating vacuum that prevents clogging, requires only a single-cylinder engine and does not contain any vacuum pumps or associated oiling systems typically required in other wellpoint pumps. The self-priming, double-acting design has an efficiency rating of over 90%, which allows for low motor capacity. The unit is extremely cost-effective to operate and can run for more than one week on a single tank of fuel.

WORKING PRINCIPLE

The double-acting piston pumps convert rotational energy applied to the pulley to linear motion to a set of pistons by two conically milled gears mounted on either side of the crankshaft. A vacuum is created inside the cylinders from the motion of the pistons. On the piston upstroke, water is drawn into the cylinder as the suction valve opens and the delivery valve closes allowing the water to be drawn into the cylinder. On the down stroke, the force of the piston causes the suction valve to close and the delivery valve to open, forcing the water out through the discharge.