CORROSION RESEARCH ROUND‐UP

Polyisobutylene for pickling tanks. In order to increase corrosion resistance of pickling tanks, an underlayer of polyisobutylene, Soviet mark PSG and 3 mm. thick, is recommended, in place of the usual two layers of rubber, followed by a layer of acid‐resistant slab and a brick lining of half‐brick thickness, using diabasic cement. Details are tabulated of six different types of rubber undercoating as hitherto used. The new form of lining is claimed to be 10 to 15% lower in cost and its weight is also in most cases less, it may be used for tanks of 4 to 8 cu.m. It is suggested that some form of grooved silicate material might be of advantage in reducing total thickness of lining and its cost, but such material is not yet made in the Soviet Union on an industrial scale. For painting the outside shell, perchlor‐vinyl lacquers are suggested: one ground coat of KhSG‐26 (to Soviet standard or GOST 7313–55) and two coatings of KhSL (to same standard). —(V. L. Vinarskii, Stal' (Steel), 1957, 17 (3), 272–273.)