Analysis of the ring gear orbit, misalignment, and stability phenomenon for internal gear motors and pumps

Due to its simple construction (only two moving parts), small size, easy assembly and maintenance, reliability, and simple operation, and inexpensiveness a gear pump can be used for wide range viscosity from 1cPs to over 1.000.000 cPs as well as with a wide range of temperatures. Moreover, the internal gear motor/pump is suitable for many different liquids, e. g. all varieties of fuel oil and lube oil, resins and polymers, alcohols and solvents, asphalt, bitumen, polyurethane foam, food products such as corn syrup and chocolate, paint, inks, pigments, soap, surfactants, and glycol. Therefore, a gear pump is one of the most popular types of pump that can be used in a wide range of the industrial fields. The principle of the gear pump is based on the “gear-with-a-gear” principle.