The ES type pump is a progressing cavity pump; it uses a 'screw' type rotor, turning in a specially formed, rubber, stator. The smooth pumping action makes it very suitable to pump oil/water mixtures without causing any emulsification.
This type of pump has excellent suction and discharged characteristic which makes it very suitable in many applications. A lift of 3 meters or even more is not a problem and long distances can easily be bridged.The pump-action is slightly pulsating but this is of no concern in the applications in which it is used.
Due to the intensive contact between the stainless steel rotor and rubber stator, it is susceptible to abrasive matter and debris in the fluid. Therefore it is recommended to use a strainer (not a filter) in the suction side of the pump to remove chips, fines and other coarse matter. A magnet, placed inside the strainer, may be of great value in reducing the wear of the pump rotor and stator.