The Stuwa propeller shaft nut

Physical force has been supplanted by innovative hydraulics. Where many shipyards still heat the screw first, then tighten the nut with a hammer and impact spanner, De Waal is already one step ahead!

By incorporating a hydraulic piston ring in the propeller shaft nut, the propeller is now mounted securely in no time, without heating or physical force.

After the screw has been slid onto the propeller shaft, the nut is tightened manually. By now using a hand pump to fill the space behind the piston ring with oil, the ring comes, as it were, ‘out of the nut’, pushing the screw the last bit over the shaft. Until the screw is tightly clamped around the cone. After this, the pressure is released from the piston, and it retracts back into the nut. The nut is now lightly and effortlessly tightened against the screw.

moeren 2The Stuwa propeller shaft nut.

Firmly secured and watertight

The Stuwa® nut is secured in a unique, weld-free manner. A special pin holds the nut, through CNC-applied notches, effortlessly secured in place. It cannot loosen by itself. Finally, the corresponding cover cap is fitted. The propeller shaft end is now watertight!

Features

  • Over 40% more pressing force than manual striking
  • Preheating of the screw is unnecessary, no risk of deformation
  • No risk of cone deformation due to heating
  • Screw shaft end is completely watertight and corrosion-free
  • Simple and ergonomic system for the mechanic
  • Conventional installation method, with an impact wrench, remains possible
  • Also suitable for the hydraulic removal of the propeller
  • When removing, it is no longer necessary to strike the propeller
  • Nut is supplied with every propeller shaft at no extra cost
  • Precise production with our own CNC machines