STP538: New Molten Salt Systems for Cleaning Stainless Steels

    Shoemaker, R. H.
    President, Kolene Corp., Detroit, Mich.

    Pages: 12    Published: Jan 1937


    Abstract

    Operating conditions determine the application of acid pickling, mechanical abrasion, and salt bath conditioning for cleaning stainless steel strip. Ecology requirements favor the use of molten salt baths as conditioning agents. Reductions in the concentration of pickling acids required can be accomplished by the chemical reactions of molten salts with the oxidized surface. The combination of electrical energy and highly active chemical salt baths is an effective method of continuously descaling stainless steel strip. A new low temperature and electrolytic process which operates at 400°F (204°C) is also quite effective. The construction of salt bath equipment from carbon steel and the inclusion of sludge collection and removal systems is recommended. A system of minimizing salt drag-out on a moving strip involves the use of high pressure steam as a scrubbing media. Synchronized roll drives are a new development in continuous strip processing through a molten salt bath. Molten salt spray systems are another new addition to the processing of continuous strip. High speed lines in the future may utilize all of these developments and clean pickling without the use of strong acids remains a distinct possibility.

    Keywords:

    stainless steels, cleaning, scale removal, descaling, chemical cleaning, salt baths


    Paper ID: STP41378S

    Committee/Subcommittee: D12.16

    DOI: 10.1520/STP41378S


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