| 摘要 |
<p>Vapour cleaning plant has in a wall of its tank (10) temperature sensors (20-22) which are arranged to control heating of the cleaning fluid in the sump (12) so that a desired top level of the cleaning vapour is maintained in the tank. In non-use periods reduced heating is effected but on fall of the top vapour level in use, e.g. due to loading of cold work-pieces to be cleaned, increased heating is brought into effect to restore the vapour level to the desired top level. Cooling coils usually provided at the tank top may be omitted with consequent power saving, and extraction air of rim extraction means may be used to cool the tops of the walls to prevent loss of cleaning fluid due to vapour creep along the walls.</p> |
