Guido Pfister No Comments

A customer reached out to us in May 2022 in Singapore, asking for our help in repairing a damaged two-stroke engine bed plate. The cast iron bed plate suffered from cracks and missing material, inflicted as consequential damage following a connecting rod failure.

Our experts immediately carried out an inspection on board. They found this main engine bed plate to be repairable, but determined that the damage area could not be accessed properly without removing the engine’s A-frame. The shipowner therefore decided to bring the 19-year old, 100 m long asphalt carrier alongside a ship repair yard in Singapore.

“We are very satisfied with your service.”

Customer’s Technical Superintendent, by email, August 2022

Damage location
Damage location

While the shipyard’s personnel dismantled the ø 38 cm bore, japanese-made engine, our specialists prepared a repair plan and discussed it with the customer and classification society. Simultaneously, they arranged for a tailor-made repair patch to be made, including a set of accompanying classification certificates.

In late June 2022, once the engine had been suitable dismantled, three metal stitching specialists from QuantiServ Singapore carried out the bed plate repair. They first removed all damaged and deformed material and dressed up the facture. They then installed the newly fabricated cast iron repair patch with Castmaster™ stitching pins. They repaired all cracks in the same manner, including a 150 mm long one that had not been visible until the deformed material had been removed.

Once all stitching pins had been installed, our specialists then added high-strength locks, made of heat treated steel. These are always installed perpendicular to the fracture line and serve to distribute stresses over a wider area. They also add additional strength to the repair.

The completed repair was thoroughly checked by Magnetic Particle Inspection (MPI). The attending classification surveyor witnessed this. And last but not least, our in-situ team carried out a laser alignment check of the main bearing pockets. This was done to rule out any deformation in the bedplate due to the impact forces exerted upon it by the broken connecting rod.

Damaged bed plate prior to repair
Damaged bed plate prior to repair
Damage area prepared for stitching repairs
Damage area prepared for stitching repairs
Classification surveyor attending the Magnetic Particle Inspection (MPI)
Class surveyor witnessing Magnetic Particle Inspection
Installation of stitching pins along the crack line
Installation of stitching pins along the crack line
Stitching in the repair patch
Stitching in the repair patch
Magnetic Particle Inspection (MPI) of the completed repair
Magnetic Particle Inspection (MPI) of the completed repair
Magnetic Particle Inspection (MPI) of the completed repair
Magnetic Particle Inspection (MPI) of the completed repair
Preparing the repaired bed plate for laser alignment check of the main bearing pockets
Preparing the repaired bed plate for laser alignment check of the main bearing pockets

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.