MODEL VPF  
VERTICAL MIXED FLOW PUMP

By adjusting blade opening to infinite stage, water flow and head can be achived and acordingly it makes energy-saving.
There are hydraulic type and mechanical type for variable pitch blade pump.
The pump can be started with impeller set at minimum opening, which faciliates starting with small starting torque.
Operation near best efficiency point makes effective against cavitation.
Pump Rptor

 

H-Q curve, System curve "R", and B.H.P.curve "L" are shown as left.
Pump operating point will be the crossing point of H-Q curve and System curve "R".
B.H.P. will be the point on the B.H.P. curve corresponding to the point on the operating curve.
B.H.P. shown as oblique lines will be reduced.

 
 
Comparison of hydraulic type and mechanical type
Comparison of hydraulic type and mechanical type

Operation Power

Oil pressure

Electric actuator

Pump size Large size of 1500mm or more Minor size below 2500mm
Operation
mechanism
Pressure oil is introduced into servo cylinder and operating rod is operated up and down with a servo piston An operating rod is operated up and down with worm gear and screw mechanism
Installation position of blade control system Motor top Middle of pump and motor
Features ・Big power can be obtained
・An operation mechanism is small and can make pump height low
・It is necessary to make a motor shaft hollow
・Oil unit is necessary
・Oil unit is unnecessary
・There is no necessity of making a motor shaft hollow
・Blade control system becomes comparatively large-size and pump height becomes high