Pieces of wood in a perforate container in a chamber are evacuated and then immersed in a liquid mixture of monomeric synthetic resin and catalyst under elevated pressure. The container of resin-impregnated wood then is transferred to a rotary chamber and tumbled under elevated gas pressure and controlled polymerization temperature to effect polymerization of the impregnated resin.
A furnace of autoclave for heat treatment of carbon articles impregnated with a fluid medium, which is provided with a smoke-elimination system including means for supplying clean air under pressure to the closed furnace and exhausting said air through a smoke incinerator or other cleaning means, and means for supplying clean air by suction to the top of the open furnace and exhausting said air through the same cleaning means. Valves are provided to control the admission and draining off of the fluid medium and to determine the course of flow of the air in order to carry out the method of operation.
The temperature of the plasticizer material which is applied to a tow band of filter material in a cigarette rod forming operation is maintained at substantially the ambient temperature of the environment in which the forming operation is being carried out thereby to provide substantially constant viscosity of the plasticizer, the temperature being maintained by circulating a cooling fluid through the plasticizer source to maintain it at a temperature of about 70.degree. F. to about 80.degree. F. Apparatus for maintaining the source temperature in the prescribed range also is disclosed.
Apparatus for impregnating wood veneer with a liquid impregnant comprises a container having an upper chamber communicated to a lower impregnation chamber. A clamping mechanism is releasably engageable to a peripheral region of the wood veneer and is cooperably received in the upper chamber in a manner to suspend the wood veneer in the impregnation chamber. An elevator overlies the container and is releasably connectable to the clamping mechanism for lowering the clamping mechanism into the upper chamber to suspend the wood veneer in the impregnation chamber therebelow. The clamping mechanism is disconnected from the elevator such that the clamping mechanism remains in the upper chamber during impregnation of the wood veneer with liquid impregnant. The impregnation chamber is evacuated by a vacuum pump after the wood veneer is suspended therein, and liquid impregnant is introduced from a storage tank to the impregnation chamber about the wood veneer. A venting valve is openable to establish ambient pressure in the impregnation chamber to impregnate the wood veneer with the liquid impregnant therein. Following impregnation, the clamping mechanism is reconnected to the elevator to enable removal of the impregnated wood veneer from the container.
An apparatus for the treatment of timber comprises a vessel having at least three chambers arranged in series for passage of the timber therethrough on conveyor belts or the like. There is means for drawing a vacuum in each of the end chambers and means for spraying the timber with a preservative liquid in an intermediate chamber, the vacuums being maintained during passage of the timber through the end chambers, by means of seals which are arranged to close and open automatically as the timber enters and leaves the respective vacuum chambers.
