Page 38: of Maritime Reporter Magazine (February 2004)

Lost and Not Found Canada

Halifax Shipyard On Hand

To Replace Lost Rudder

In November 2003 the Gorthon Lines AB ves- sel Margit Gorthon lost her rudder in the St.

Lawrence River. The RoRo vessel features star- board side ramps and measures 463.9 x 73.1 ft. (141.4 x 22.3 m) and is 14,240 dwt. Halifax

Shipyard visited the vessel and found that not only the rudder was gone, but the 343 mm rudder stock broken in three pieces and the steering gear flat bottom shell ripped and twisted. One of the pieces of the rudder stock was embedded in the rotary vane steering gear. All CP propeller blades were damaged beyond repair and had to be replaced. After some number crunching and dis- cussions, Gorthon Lines AB decided to have its incapacitated vessel towed to Halifax Shipyard for repair in late November 2003. The vessel was docked in Halifax Shipyard's in their graving dock that is 567.6 x 77.1 ft. (173 x 23.5 m) with an 26.2 ft. (8 m) draft over the keel blocks.

The work scope included removal of the steer- ing gear, its seat and the damaged deck and shell plates, remove the remainder of the rudder stock and access other peripheral damage, including the propeller blades. A new rudder had to be built; the rudder stock was a forging and difficult to create was dispatched from the Owner with the new propeller blades. The shell requires renew- ing as well as the aft peak tank top and a new seat manufactured and machined for the steering gear.

As well as this a great deal of machining was required on the new rudder and the bottom and top pintles on the remaining stern frame as well as the new steering gear seat. Material was found for the heavy rudder top and bottom plates but stainless steel liners for the pintles could not be obtained in a timely fashion and as a result of this solid stainless steel rounds were used and drilled 1. 2. 3. 4. 5. 6. 7.

The ship in Dock A

Alignment preparations

Rudder stock fitted

Hardening the palm bolts

Rudder fitted access welding

Flooding the dock

Vessel leaving

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Circle 227 on Reader Service Card

February 2004 33