| 摘要 |
412,175. Treating wood. WILL, H. E., 53A, Br³derstrasse, Remscheid, Germany. Dec. 15, 1932, No. 35617. [Class 140.] Wood is dried and impregnated by treatment with steam and the vapour of the impregnating agent in superheated condition and moving with a velocity of at least several metres per second. During a drying or impregnating operation, a constant ratio is maintained between the velocity of circulation and the degree of superheat, but these two factors are progressively reduced during the operation. To determine this ratio, thermometers are introduced at different distances from the surface of a specimen of the wood to be treated. For a given speed of circulation, the degree of superheat is varied until the curve showing the relation between temperature and distance from the surface is parabolic, whereupon the required ratio is determined. The operations may be conducted under reduced or elevated pressure. Steam or oil of turpentine vapour may be used as " catalytic " agent to facilitate impregnation, e.g. with a phenol-turpentine mixture. The operations may be conducted in container m, into which the timber is run on carriages b. A series of variable speed fans g circulate the steam, which is formed from the wood and rapidly displaces the air initially present. The impregnating agent is admitted through a perforated pipe i, and passes with the vapour current through heating apparatus h. |
