CECIL grows up

Effective systems for secondary side steam generator maintenance are critical in maximizing the life of PWR steam generators. Corrosion products formed throughout the secondary cycle settle on top of the tubesheet and promote degradation of the tube bundle. Foreign objects introduced into the secondary side during either initial fabrication or maintenance activities impinge on tubes during operation and can eventually cause the wall to wear through, causing primary to secondary leakage. Ultimately, if a sufficient number of tubes are damaged by these corrosion or wear mechanisms and are subsequently plugged, the steam generators have to be replaced. CECIL (Consolidated Edison Combined Inspection and Lancing system) was developed to help extend the life of steam generators by providing superior secondary side maintenance capabilities. CECIL 4 is a teleoperated robot which can remotely perform PWR steam generator secondary side inspections, soft and hard sludge removal, sludge sampling and foreign object search and retrieval. Its main features are described here. (author)