"220V AC Cooling Fan" axial fan and axial flow pump structure is basically the same. Spindle, the impeller, the current collector, guide vanes, the housing, the rotor blade adjustment means, and the main components of air intake box diffuser and the like. Because "220V AC Cooling Fan" axial fan (including axial flow pump) has a large round enough, it can be installed rotor blade adjustment mechanism in the inner wheel enough. Moving blade adjustment mechanism has hydraulic adjustment and mechanical adjustment of two types. The agency may adjust the mounting angle of the impeller blades, the fan operating conditions were adjusted. At present, domestic and foreign large "220V AC Cooling Fan" axial fans and axial flow pumps have achieved the variable pitch. Vane axial fan is an important component, which can adjust the flow direction of the air flow through the front of the impeller or impeller after.