Complete renewal of stern tube assembly allows passage through Panama Canal22/12/2016
When a steel wire got stuck in the stern tube seal assembly of a 156-meter Dutch vessel, it experienced a severe oil leak. The ship needed to pass through the Panama Canal to reach its next destination, but the leak had to be repaired before it was allowed to do so. We flew in a diving team immediately to carry out a fast underwater repair that would help the vessel continue its schedule.
Our team arrived in Balboa, Panama, where the vessel lay at anchorage and sailed to the ship on a workboat loaded with all the equipment needed for the operation.
A thorough underwater inspection revealed that while the wire had been removed by a local diving company, the damage to the stern tube seal assembly was extensive. The rope guard was severely dented and the seal housing had been destroyed. Both needed to be completely replaced. Because the stern tube seal assembly consisted of a split type housing, our team could carry out the entire replacement underwater.
First they removed the affected parts. Because the seal assembly had already filled up with water due to the damage, the divers did this in the wet. Next they installed the flexible mobdock and created a dry working environment around the stern tube seal assembly. The team could then start installing the new housing.
The liner was replaced first, as this had also suffered damage from the steel wire. The diver/technicians then bonded the four new stern tube seals and installed the new housing.
All remaining parts of the stern tube seal assembly were then reinstalled and secured, including a new rope guard. A leakage test was carried out with positive results, after which the divers removed the flexible mobdock.
The operation was performed by our team in the same time frame as a regular stern tube seal replacement, despite the larger scope of work. Working together with our local support base, they worked in shifts to keep the down time to the absolute minimum for the vessel.
After the repair, the owner could sail his vessel through the Panama Canal free of oil leaks, towards the next stop on the schedule.