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VARIFOLD-Design

VARIFOLDs are designed to solve problems which have affected folding propellers since they were first introduced.

Working with SPW, and other companies in the Bruntons group, who design and manufacture propellers for vessels as diverse as nuclear submarines and luxury motor yachts, the designers have achieved their objectives.

The resulting range of propellers share design features which are little short of revolutionary. VARIFOLD marries virtually all the benefits of a fixed propeller when motoring, to those of a low drag folding propeller when sailing.

VARIFOLD's very low noise and vibration characteristics are achieved by state of the art blade design and proper helical pitch distribution, including pitch reduction towards the blade tip. This radically reduces cavitation and, in combination with the skewed blades, greatly reduces noisy pressure pulses against the hull.

No other manufacturer offers this full package on such a wide range of folding propellers. Putting the technicalities to one side it’s very simple - VARIFOLDs work!

Opening technique with a difference

VARIFOLD's unique opening technique will impress you. You see, this folding propeller not only opens by means of centrifugal force, but also by means of the shaft torque, resulting in particularly smooth and reliable opening.The VARIFOLD has a cambered design. This specially cambered blade profile delivers very high thrusts and quiet and smooth propeller running.

the VARIFOLD in action:

Varifold sailing

VARIFOLD, in all its versions – two, three and four blade, is an exceptional low drag racing propeller. Unlike some folding propellers, on most installations VARIFOLDs do not rotate when sailing, even at higher speeds.

Varifold astern

Varifolds open when you go astern! This is again a feature of the design which relies on hydrodynamics as well as inertia to assure reliability. Thrust is greater than other folders by virtue of the design.

 

Varifold ahead

Most folding propellers suffer from varying degrees of noise and vibration and the problem becomes worse the more power the propeller has to deliver. If your yacht has an engine from 20hp to 750hp, there is a VARIFOLD for you which will provide high thrust with smooth and quiet running.