Cecil

Problem: Conventional sludge lancing (water spray) techniques do not remove all the corrosive sludge material that builds up on the tubesheet. Foreign object retrieval has been difficult in the annulus region and virtually impossible in the tube bundle. Corrosion products formed throughout the secondary cycle settle on top of the tubesheet and promote degradation of the tube bundle. Foreign objects introduced during initial fabrication or maintenance activities also impinge on tubes during operation and can eventually wear through tube walls causing primary to secondary leakage.