Sandvik Steel has extended its manufacturing capability for seamless titanium and zirconium tubes with the availability of two additional titanium grades. The two new grades, designated ASTM/ASME grades 12 and 26 offer enhanced corrosion properties for heat exchanger and piping applications in the hydro metallurgy, LNG, petrochemical refining and salt refining industries. ASTM/ASME grade 12 is a titanium alloy containing 0.03% molybdenum and 0.8% nickel. ASTME/ASME grade 26 is an unalloyed titanium with the addition of 0.08-0.14% ruthenium to increase corrosion resistance. Both grade 12 and grade 26 are particularly well suited to use in heat exchangers and coolers using chlorinated seawater as coolant and when there are risks of crevice corrosion. Grade 12, in addition, offers enhanced heat, erosion and erosion corrosion resistance. Both grades are also designed to provide enhance resistance to dilute reducing acids and crevice corrosion or pitting on hot (> 75 degrees. C) chloride or halide solutions. Sandvik Steel’s manufacture of seamless titanium and zirconium tubes is undertaken with a complete integrated process that begins with the melting of the titanium or zirconium sponge of from zirconium ingots and ends with the finished seamless tubes. The production process has been specially designed to work with non-ferrous metals. The size range available covers outside diameters from 8mm to 35mm in tube lengths up to 28 meters for titanium and 14 meters for zirconium, supplied as straight or as U-bent tubing. Since introducing the new grades, Sandvik has received its first commercial orders for U bent grade 12 titanium heat exchangers tubes intended for LNG, well head cooler units in the Persian Gulf. The units operate in highly corrosive tube side conditions of 8000 ppm hydrogen sulfide gas at 93 degrees C and shell side sea water with 0.2-0.5 ppm chlorine at an average temperature of 25 degrees C.
