Rudders are used in ships to achieve a change in direction from the current path. This ppt is gives details of the types of rudders used

1. Rudders A rudder allows the ship to turn, simple plates have been superseded by plates welded to cast or fabricated frame. Rudders are hollow and so provide for some buoyancy . In order to minimise the risk of corrosion internal surfaces are provided with a protective coating and some are even filled with foam. A drain plug is provided to allow for the drainage of water , enable internal inspection to be made using fiber optic device and even allow for the limited application of a protective coating.

8. Spade Rudder

16. PLEUGER RUDDER A normal rudder can only be effective when the ship is moving, and the torque it exerts varies with the square of the speed ,so that at very low speeds it can be very ineffective. A pleuger rudder incorporates a submersible electrically driven propeller which can be run when the main propulsion is at rest . In order to attain maximum effect and manoeuvre the ship at rest the rudder is able to turn to 90',owing to this normal floating linkage hunting gear cannot be used, and a special cam hunting gear used. For normal course keeping the angle is limited to 35',and a warning signal initiated if exceeded.

17. THE VOITH SCHNEIDER PROPELLOR

20. JET FLAP RUDDER

22. ROTATING CYLINDER RUDDERS

25. Becker flap