An internal gear pump uses internal and external gears.The gears themselves are lubricated by the fluid, which is of a lubricating nature. The internal design is seen as being reliable, easy to operate and maintain – due to only two moving parts being present.The pump will usually contain at least one bushing.The design can also be modified to include a crescent shaped portion that improves performance when pumping high viscosity fluids with low speed.Internal gear pump can transfer high viscosity fluids, fuel oils, lube oils, various chemicals, resins, paints, pulps, acids, bitumen etc. China manufacturer Hoffwell Pump provide good quality internal gear pumps with good price. Feel free to contact me to get more information.