Pressure Process of Applying Preservative

Pressure process is one of the most efficient process in applying preservative. It is of two kinds.

1.Full cell process:In this process cells of wood tissues are desired to practically completely filled with preservative.Woods are loaded on a special kind of trolly and then put in autoclave machine.The vacuum is applied inside the autoclave to remove air from wood as much as possible.Then heated(generally 210 degree Fahrenheit) preservative is pumped in the autoclave with 125 to 200 psi pressure.


2.Empty cell process:In this process preservative forms merely a thin layer on wood cells.All the process is same with full cell process, except that before applying preservative 50 to 75 psi pressure is created to fill wood cells with air and then preservatives are added with about 200 psi pressure.

The Essential Properties of Preservatives of Wood

1.It should be safe in handling and use.
2.Non injurious to wood tissues and do not react with them.
3.Should not get washed away and permanently preserve.
4.Should be such that decorative and ornamental paints could be applied on wood.
5.Should be non flamable.
6.Penetrate thorough timber.