Volumetric loaders and hoppers are used in a variety of commercial and military applications. In general, a volumetric loader includes a large supply of a material (liquid, granules, powders, cast composite propellants) that is dispensed in small quantities to a number of small receptacles. The material could be harmless (grains, candy) or hazardous (ignitable propellants, petroleum products, explosives). For simplicity and cost effectiveness, many volumetric loaders utilize gravity to supply the material to one or more dispensing or casting nozzles. This type of dispensing necessitates nozzles that minimally obstruct the flow of any material. Further, in cases where precise amounts of the material must be dispensed, casting nozzles must be producible with minimal variation.
Navy researchers have developed a casting nozzle for liquid dispensing made from cured chemically inert photopolymer material so that the interior surfaces are smooth and glassy. This surface insures a smooth flow of material. The nozzle is manufactured via stereo-lithography to tight tolerances. A conductive metal coating such as nickel or copper is applied to the exterior surfaces to prevent any unwanted electrostatic charges reaching the interior of the nozzle. Electrostatic charges could be hazardous in cases where the material passed through the nozzle could ignite and explode or burn.
- Cured photopolymer provides a smooth interior nozzle surface that offers minimal resistance
- Photopolymer material allows the nozzle to be rapidly manufactured at scale with minimal variability using stereo-lithography equipment and processes
- Metal coating prevents electrostatic burning or ignition of material
- US patent 8,905,335 available for license
- Potential for collaboration with Navy scientists and engineers