Hydrex performs underwater PBCF installations

NOVEMBER 26, 2013 — More than 2,300 ships have now been fitted with Propeller Boss Cap Fins (PBCF), a proven fuel saver developed by Mitsui O. S. K. Lines, Ltd.

PCBFs work by recovering the energy otherwise lost in the propeller's hub vortex, resulting in energy savings of up to 5 percent.

Last month Hydrex enabled two tankers to start making these savings without waiting for their next drydockings. It installed them underwater during their respective stops in Ghent and Antwerp.

The first operation was performed on a 183-meter tanker berthed in Ghent. After the team arrived at the vessel's location with one of the Hydrex workboats, they started the operation with a full inspection of the propeller. Next the diver/technicians cleaned the area where the spinner cone (PBCF) was to be installed. They then lowered the cone into the water and positioned it on the propeller. When this was done, grease was inserted in the space underneath the propeller cone for lubrication and the bolts were put on torque and secured with wire, finishing the replacement of the PBCF. The Hydrex team worked around the clock to finish the operation as quickly as possible.

pcbf squareThe exact same procedure was used during the operation in Antwerp on a 130-meter tanker. The alignment of both PBCFs was monitored on an underwater video camera and supervised by the manufacturer's specialist on the workboat.

Last year, Hydrex replaced two PBCFs on a 110-meter tanker in Singapore. This was the first underwater installation of a PBCF, according to the manufacturer.