Abstract: An extrudable aluminum alloy composition includes, in weight percent, between 0.60 and 0.90 manganese, between 0.45 and 0.75 copper, between 0.05 and 0.24 magnesium, less than 0.30 iron, less than 0.30 silicon, less than 0.05 titanium, less than 0.05 vanadium, and a Cu/Mg ratio higher or equal to 3. It also relates to aluminum alloy heat exchanger extruded or drawn tube and extruded or drawn aluminum alloy tubing having the above-described aluminum alloy composition. It also relates to a heat exchanger comprising a plurality of extruded or drawn tube sections having the above-described aluminum alloy composition and a process for manufacturing same.

Abstract: An apparatus and a method for tapping molten metal from below a molten electrolyte layer less dense than the metal is described. The apparatus comprises a pipe comprising a protruding enlarged wall portion at an operative end which is immersed in the molten electrolyte and metal during tapping operation. The enlarged wall portion helps to minimize entrainment of electrolyte residue from the electrolyte/metal interface during tapping. The orientation of the enlarged wall portion may be in the general direction of the crucible.