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Rudder repair

 Slot Welding to be carried out. Plates, Welding rods, welders Qualification & procedure of repairing must be approved by class surveyor. Second plate is called Wrapping  Plate / Cover Plate. Plate is prepared by marking of the frames on it & then slots are cut. Then the plate is bend on the framework & is welded to the frames. Slots are filled with the weld. These welds are ground & made smooth.
 Pressure Testing of Rudder :
Gravity method :
Fill water in rudder upto 2.46m above top of rudder & observe it. Water level should not drop.
 Hose Test :
 Drain plug has to removed & hose is applied on the slot welds & observe if water is coming from the drain plug. This is to be done before gravity method.
 Coating :
 Open top plug , put bottom plug with cock. Fill 50 % water inside & 20 % with paint. Drain water slowly by cock. This is called float coat painting.


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