Cleaning of workpieces via solvent vapour in heated tank - where continuous filter strip traps dirt particles falling off workpieces together with condensed vapour

摘要

The tank contains heater elements covered by the liq. so the latter is evaporated to form a vapour zone above the liq.; and the workpieces are suspended in and/or conveyed through the vapour zone. Immediately above the liq., and below the vapour zone is a filter stripo which traps the solids (i.e. the dirt, swarf, etc.) falling downwards with the condensed vapour from the workpieces. In the pref. plant, filter strip is conveyed via rollers from a spool so it travels above the liq., and a sensor detecting the thickness of the solids on the filter drives an electric motor for periodic renewal of the filter. Continuous removal of dirt etc. which would otherwise contaminate and possibly decompose the liq., which is e.g. a chlorinated hydrocarbon.