GB399717A - Process for cleansing articles of metal and the like by means of volatile solvents and apparatus therefor - Google Patents

Abstract

<PICT:0399717/III/1> In the cleansing and degreasing of articles of metal, glass, horn, celluloid and the like by exposure to heavy solvent vapours, e.g. of tri- or per-chlorethylene or carbon tetrachloride, and wherein escape of vapour from the washing vessel is prevented by one or more laterally arranged cooling spaces communicating with the upper part of the vessel, the level of the vapour in the vessel is lowered after the degreasing operation, so that the articles may dry, by placing the lower part of the vapour space in communication with the lower part of the cooling space. For example, a cage 7 containing the articles is lowered on to a grating 8 above liquid solvent in an open washing vessel 1; a casing 2 is suspended from rollers 3 so as to dip into the liquid and form an annular space 5 within which are arranged cold-water pipes 6. During the cleaning operation the liquid is boiled and surplus vapour falls over the upper rim of the casing 2 into the cooling space 5, so limiting the vapour level in the washer 1; when cleansing is finished the casing 2 is lifted above the liquid so that the lower end of the cooling space 5 communicates with the space below the grating 8, the vapour level is lowered to that of the lowest cooling pipe 6, and the articles dry in the air from above. In other apparatus, communication between the lower ends of the vapour and cooling spaces is controlled by valves; suction pockets are arranged near the top of the washing vessel to withdraw air that has become charged with solvent vapour by diffusion; hinged or sliding covers above the washing vessel may be so arranged that when closed they close the openings to the suction devices; the articles are contained in a closed rotatable cage or are carried through the washing vessel, and may be rotated therein, on conveyers, and gutters are arranged beneath the cooling pipes.