Semi-hydraulic three diaphragm pump for corrosive products under low pressure conditions. Parts in contact with the pumped liquid are reinforced nylon, Kynar and AISI 316L. BlueFlex ?  Membrane. Viton?  Seals. Die-cast cart with oil bath mechanism, clear plastic fuel tank for visual level control. Hydraulic pneumatic dampers are provided to improve the regularity of operation and reduce pulsation in the transmission circuit. Kit for remote installation of fuel tank upon request. Drain plug. Segmented pistons increase the efficiency of membrane protected "oil pad" systems. The newly designed film locking system avoids contact tearing even under heavy use. Valves with spherical fan-shaped profiles reduce liquid resistance and improve volumetric efficiency. Strong support feet are fixed to the pump housing. Screws in AISI 304. Overpressure valve with reset function. Flanges are available for reduction gears, pulley applications or hydraulic motors for electric or gasoline motors.