Plugging of the defected tubes is another practical means, and the use of protective sleeves might also be considered. Counter-measures against droplet erosion are briefly reviewed and involve the reduction of steam velocity and/or degree of wetness. It is assumed that impact with wet steam produces high-pressure transients and initiates high flow away from the points of impact. Similarly, no feather-like structure indicative of hydride formation is noted. Microscopic examination reveals the absence of any corrosion products on the surface. Along one side of the crack a series of small, circular metallic protrusions develops. The crack is unbranched and progresses in a stepwise fashion. At the sites of maximum impact by wet steam, the tube wall thickness is reduced to zero, and the tubes crack open under pressure of the cooling water. Received 27 June 2000 accepted 6 September 2000Ībstract A description is given of a new form of droplet erosion of titanium condenser tubes. Shams El Din”, Badr Bin Ashoorb “Material Testing Laboratory, Abu Dhabi Water and Electricity Authority, Research Center, PO Box 5411 I, Abu Dhabi, UAE Fax +971 (2) 508-1506 bCorrosion and Inspection Section, Al Taweelah Power Company, Abu Dhabi, UAE Desalination 133 (2001) 149- 153 A new form of titanium condenser tube droplet erosion M.E.
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