Monthly Archives: October 2013

When others can’t- We can!- Underwater Shaft seal replacement

DSC02693More and more debris is being found in our oceans throughout the world.  This debris includes large masses of fishing line and net.  While transiting the southwestern USA, a cargo vessel began experience excessive sea water ingress on the aft shaft seal.  Thinking it was a simple matter of just cutting away some fishing line, the ship manager contracted the work with a local dive company to inspect the stern tube and remove the fishing line.  In the process of fish line removal it was confirmed that some of the mono-filament fishing line was sucked into the lip seal arrangement.  Through the extraction process further damage to the seal arrangement occurred.  With the job exceeding the capabilities of the dive contractor on site, Subsea Global Solutions was called in to perform a permanent repair to the at shaft seal.  Within 16 hours of being initially notified by the ship manager that our services were required, Subsea Global Solutions mobilized all of the necessary equipment and personnel to perform this aft shaft seal repair in less than 48 hours.

DSC01708With the rope guard already removed, Subsea Global Solutions installed the Transhab flexible hyperbaric cofferdam over the affected area of the vessel.  With the critical area of the stern tube dry and in a climate controlled environment, Diver / Technicians entered the Transhab and fully assessed the aft shaft seal system.  With Original Equipment Manufacturer factory training and certification from the manufacturer of the seal system, the Diver / Technicians began a class approved and OEM warranted repair.  All lip rings were properly disassembled.  The seal housings were evaluated, overhauled and prepared for re-installation.  The shaft seal liner was inspected, grooving measured and evaluated.  It was determined that the existing liner was within factory specifications so replacement or removal of the spacer plate and or liner was not required.  If required, the seal shaft seal spacer plate or shaft liner could have been removed and or replaced in a completely dry environment in the TransHab flexible hyperbaric cofferdam utilized by Subsea Global Solutions.

With all critical components measured and cleaned, the Diver / Technicians performed the new lip ring bonding process.  Utilizing the same process, same jigs, and glues utilized by factory approved technicians performing the work in the dry dock, the Diver / Technicians completed the most critical part of the shaft seal replacement.  Once the seal assembly was completely assembled, the Diver / Technicians performed factory required feeler gauge tests and pressure tests.  All pressure tests and mechanical inspections were performed to the full satisfaction of the attending ship manager and class surveyor.

In less than 43 hours, Subsea Global Solutions came and went.  We are your trusted resource to deliver unrivaled service.  The Ship Manager was excited to see the stern lights go over the horizon without any notations or open class items.  Subsea Global Solutions is your trusted resource to keep your vessels in service.  One world, One Ocean; Subsea Global Solutions is your underwater contractor any where around the world.