Neptune Low Volume Pumps

Neptune Model 481-S and 501-S hydraulic diaphragm metering pumps are built to deliver very low flows, repeatable and accurate ranging down to quarts per day. Discharge pressures are higher than are possible with mechanical diaphragm pumps. Explosion-proof models are available for use in hazardous atmospheres.

These pumps are especially popular in oil/gas production, oil recovery and refineries. Typical applications include the injection of antifoam agents, corrosion inhibitors and other additives injected at very low volumes but high pressures. (Refer to curves on reverse side.) These pumps are also used for neat feeding of boiler chemicals.


High discharge pressures, to 3000 psi (210 kg/cm2) Exceeds limits of most small pumps, ideal for high pressure systems

EZE-CLEAN valves -- Cartridges can be removed for cleaning without disturbing piping

Pneumatic and electric stroke-length control available -- automatic capacity control in response to standard 4-20 mA process signal (variable speed drives may not be used with Models 481 or 501 due to low stroking speed)

Explosion-proof motors available -- suitable for use in hazardous atmospheres

Low flow-ratesquarts/day -- accurate, reliable chemical feed