When the New Zealand operated ropax ‘Straitsman’ hit an unknown object while sailing between Wellington and Picton, an underwater inspection was necessary.
This showed that the Strait Shipping operated vessel had sustained severe damage to the four alu-bronze CPP blades.
As a result, ‘Straitsman’ had to sail to the Thales Shipyard in Sydney, NSW for repairs.
One of the blades was found to be badly damaged on the edges with more material missing than could be replaced with regular MIG welding.
Due to the vessel being a former Danish ferry, MarineShaft was contacted to provide a quote for the repairs, as the company had attended her sistership on several occasions, while both vessels were operating in Denmark.
MarineShaft was awarded the repair contract and welding material plus equipment was sent to the shipyard, followed by two certificated welding technicians.
Once on site, the technicians made a model and cut the plate material for a new blade tip. One of the blades also needed straightening, which was also carried out on site.
All of the blades were welded up, balanced and ground, and all the required crack tests were carried out. MarineShaft has class approval to perform LPI (Liquid Penetrant Inspection) without being witnessed by an independent third party.
The NDT (non-destructive test) was witnessed by a local Bureau Veritas (BV) surveyor.
Strait Shipping’s technical manager, Ollie Muller said: ”MarineShaft mobilised quickly and had their technicians travel halfway around the world to get to our vessel. They know their trade very well. The proof is in the propeller blade repairs that were successfully and expertly carried out within the time constraints of our docking. We were very impressed at the high level of craftmanship that (the technicians) Johnny and Leif put into the repair.”
