Covington, L. C.
Senior research engineer, Titanium Metals Corporation of America, Henderson, Nev.
Pages: 8 Published: Jan 1976
Pitting problems have been encountered in titanium tubes in heat exchangers handling hot saturated brines. These pits appear to be of two types. One type results in symmetrical holes about one-fourth inch diameter. These are associated with scratches in which iron is found to have been smeared into the titanium surface. The second type results in large irregular shaped holes. These are believed to be associated with salt plugs. This second type of pitting is believed to be initiated by the galvanic couple between the titanium tubes and the Monel tube sheets. Use of titanium tube sheets might eliminate the pitting problem but could introduce a crevice corrosion problem unless the tubes are welded into the tube sheet. An alternate solution is the use of titanium alloy tubing that is resistant to pitting attack.
titanium, pitting, corrosion, brines, heat exchangers
Paper ID: STP41403S