Repair of rudder stocks/pintles by weld cladding Rudder stocks and/or pintles may be repaired by welding replacing wasted material by similar weld material. After removal of the wasted area (corrosion, scratches, etc.) by machining and/or grinding the build-up welding has to be carried out by an automatic spiral welding according to an approved welding procedure. The welding has to be extended over the area of large bending moments (rudder stocks). In special cases post weld heat treatment has to be carried out according to the requirements of the Classification Society. After final machining, a sufficient number of layers of welding material have to remain on the rudder stock/pintle. A summary of the most important steps and conditions of this repair is shown in the Figure (Lower). In the case of rudder stocks with bending loads, fatigue fractures in way of the transition radius between the rudder stock and the horizontal coupling plate cannot be repaired by local welding. A new rudder stock with a modified transition geometry has to be manufactured, as a rule (See Example 1). In exceptional cases a welding repair can be carried out based on an approved welding procedure. Measures have to be taken to avoid a coincidence of the metallurgical notch of the heat affected zone with the stress concentration in the radius’ area. Additional surveys of the repair (including non-destructive fracture examination) have to be carried out at reduced intervals.
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