Liquid ring pumps with built-in operating water circuit in compact design Also known as the Elmo Rietschle “Pump in a Box”, these portable units are oil free and air cooled. They include an L-BV liquid ring pump, industrial electric motor, discharge separator, seal water cooler and discharge air cooler. To install – simply connect the suction line and motor and fill the water tank – it’s ready to go! Maintenance and wear are minimal thanks to contact free compression and a built-in discharge air cooler. Additional features include: quiet operation, continuous duty design and suitability for humid environments. The pumps work reliably in continuous operation and are vapor resistant and insensitive to condensation of the pumped air. Operation with final vacuum or a closed suction valve is also trouble free; the pump remains cool, and current consumption decreases to the minimum value. The sound pressure level is between 63 and 76 dB(A) at 50 Hz operation, depending on pump size. This means that sound absorbing covers or discharge air silencers are not required.