Cathelco protects T-AO 187 class pipework

Cathelco Ltd., Chesterfield, U.K., has supplied marine pipework anti-fouling systems for a complete class of Military Sealift Command fleet replenishment oilers.

The final vessel in the series of 14 Henry J. Kaiser Class T-AO 187 vessels to be installed with a Cathelco system will be the USNS Patuxent, which launched in 1991.

The orders for systems were won by long established Cathelco agent Allied Marine Services Inc., Stevensville, Md.

"The Military Sealift Command in Norfolk, Va. , Fleet Managers for the T-AO 187 Class ships, are very pleased with the Cathelco AF systems' easy installation, excellent performance, the timely delivery and after sales support received from Allied Marine Services and Cathelco," says John Hautala, sales engineer at Allied Marine. "We have delivered 13 out of 14 shipsets and the last order for the USNS Patuxent has been received and is being processed."

The Cathelco system is based on the electrolytic principle and designed to protect seawater pipework systems against blockages caused by barnacles and mussels which can restrict the flow of cooling water to engines and auxiliary systems.

On the USNS Patuxent, the system protects four seachests with flow rates of 2,000 cu.m/hr. Each of the seachests is fitted with two copper anodes and one ferrous anode which are wired to a control panel.

In operation, the copper anode produces ions that are carried throughout the pipework system and create an environment where mussel larvae do not settle or grow. At the same time, the ferrous anode releases ions into the system that coat the internal surfaces of pipes to suppress corrosion. Ferrous anodes are used to protect cupro-nickel pipework, as is the case in the USNS Patuxent, while aluminum anodes are more commonly used on vessels with steel pipework.