Underwater installation of propeller cone fins offers immediate fuel saving

Propeller cone fin ready to be lowered into the water. [Image: Hydrex]

Recently, underwater repair and maintenance specialist Hydrex installed propeller cone fins on two chemical tankers: one in Antwerp and one in Rotterdam. Both operations were carried out with the company’s dive support workboats. Stationed in these ports, they allow for immediate mobilization.

Propeller caps can recover energy losses in the propeller hub vortex in the propeller’s slipstream. This decreases fuel consumption by from 3% to 5%, according to the manufacturers, and reduces cavitation on rudders and hulls.

Hydrex says it can install propeller cone fins underwater on any size and make of propeller, on both new build or in-service vessels.

A direct result of these underwater installations is that an owner can instantly start benefitting from the fuel savings a propeller cone fin brings, without having to wait until the vessel’s next scheduled drydocking for the installation.

Hydrex carries out these operations following the specific procedures required by the propeller cone fin manufacturer, adapted for an underwater installation.

After a preliminary inspection the divers remove the propeller cap and clean the flange where the device is to be installed. They then lower the propeller cone into the water and position it on the propeller. The bolts are put on the correct torque and secured. Hydrex teams can work in shifts around the clock to finish the operation as quickly as possible.