This series pump applies to delivering non-corrosive lubricating-oil or equivalent liquid without solid particles and fibres at temperature below 80 centigrade and with the viscosity of 5*10-6-1.5*10-3m2/s(5-1500cst). And it can give performance as transferpump or booster pump in oil delivery system. It can be also applied as a fuel pump for delivery system, pressurization and injection in fuel supply system and in all industry fields as lubricating pump.