1. Work principle:
driving gear (outside rotor)with internal tooth drives the internal rotor and turns in same direction in the full closed pump body.The inlet from the outlet.When it turns,negative pressure formed at the suction port,the liquid inhaled and being take to thr outlet by rotor,then the liquid is wxpelled from th discharge port sa the gears mesh.The transpor-tation of liquid finished.

2. Structure Feature:
As figure I The pumps are mainly composed of internal rotor,outside rotor,shaft,pump casing,front cover,seal,bearing etc.
The pump'seal adopts packing seal or mechanical seal.When the delivered medium is high temperatur ,high visc or strong corrosion,packing seal should be adopted.
When the delivered medium is easy crystallinic ,we can designthe heat preservation jacket in pump casing and front cover in order to melt the medium with steam wen working.The pump can be also fitted with the safty valve. The pump set is composed of the pump,motor and baseplate.
The driving way is belt wheel driving or coupling driwing.

3. ADVANTAGES:
1) Steady edlivery without pulsation ,little vibration and noise.
2) Outstanding self-priming abitity.
3) The same rotary direction of internal rotor and outside rotor results in little wear and long loperation life .
4) The pump's flow capacity can be changed through adjusting the speed.
5) It's specilly suited to deliver high viscosity medium.

Caterpillar Type VanePump Specifications: