Corrosion protection in place for Tupi Nordeste floater

May 4, 2011
Cathelco is supplying a hull corrosion protection system for Petrobras’ FPSO Cidade de Para.

Offshore staff

CHESTERFIELD, UK -- Cathelco is supplying a hull corrosion protection system for Petrobras’ FPSO Cidade de Para.

The vessel is being converted from the 265,243 dwt VLCC Mt Theseus at the Keppel Shipyard in Singapore. On completion, it will sail to Brazil to work on the Tupi Nordeste development. SBM Offshore has a 20-year charter and operation agreement with Petrobras.

Cathelco’s impressed current cathodic protection system (ICCP) will protect the entire wetted surface of the 322-m (1,056-ft) hull against corrosion.

It will comprise two components. The 400 amp forward system will incorporate a thyristor control panel connected to two hull-mounted ‘diver change’ linear loop anodes and reference cells. The 800 amp aft system will have eight ‘diver change’ linear loop anodes and reference cells.

“This vessel will operate for 20 years without drydocking and therefore the Cathelco system has been designed with diver changeable anodes which can be changed at sea, if necessary”, says Aneel Mumtaz, a corrosion engineer at Cathelco.

The reference electrodes will measure the electrical potential at the hull/seawater interface and relay a signal to the control panel, which automatically raises or lowers the output to the anodes.

Current emitted by the anodes neutralizes corrosive activity on the surface of the hull, ensuring optimum corrosion protection throughout the vessel’s life, Cathelco claims.

05/04/2011