Gear pump is kind of positive displacement rotary pump that transfer liquids using rotating gears. They work through the engaged gears that create vacuum pressure with casing to deliver the fluid media.
They are typically suited for viscosity pumping applications such as clean fuel or lube oils, resin, bitumen, paint, ink, adhesives, or soaps. The comparisons of internal and external gear pump as bellow:
Internal gear pump | External gear pump |
2 A rotor and idler gear as rotor assembly | 2 A pair of external gears as rotor assembly |
2 Two bearings or shaft sleeve to support shaft | 2 Four bearings to support shaft |
2 Pump design is bulky with bearing bracket | 2 Pump design is compact |
2 Higher fluid temperature and viscosity applicable | 2 Large outlet size and high capacity |
2 Low pump speed with reducer | 2 Speed as per motor poles |
2 More smooth and constant flow as gears roll in the same direction | 2 Work to higher pressure,less expensive |