RUDDERS

In order to keep the boat's course during navigation as well as in the waterways to port access and docking maneuvering, an appendix or rudder located in the stern of the ship is needed. These appendices are metallic surfaces of diverse forms and shapes that turning on a vertical axis generate a variation on the water stream.

From the desktop of

Gustavo Silva

The rudder, without a doubt is one of the vital elements of the ship. Classification Societys usually allow a special chapter for design and construction. In the drawing-board phase they develop theories about loads on the rudder structure classified as follows:

a)      Transverse force: The one applied to the rudder by water pressure.

b)      Flexor moment: force applied to the rudder itself when turning the ship.

c)      Dynamic forces: the stress delivered to the rudder by wave movement.

The rudders are classified according to their structure, their type of assembly and their distribution of shovel with respect to their spin axis, these types occur generally:

Ø     Without compensating.
Ø      Compensated.
Ø     Simple rudder.
Ø      Compensated in the superior support of the helmet.
Ø      Semi compensated in two supports.
Ø      Compensated constant.
Ø      Semi compensated.

Operating forces on the structure of a simple rudder

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