Description of an IMP-PG plant

The wood impregnating and coating system in autoclave

The plant is made up of a very particularly thick autoclave (1) so as to support a maximum vacuum of 400 mmHg or 700 mmHg. The elements to be treated are loaded and positioned on a moving frame (18) equipped with a trolley, which moves into the autoclave on rails held internally at the top and bottom. At the bottom of the autoclave there is the deposit (2) containing 70 to 100 litres of impregnant or coating. A pump (4) pumps the product to a series of atomiser outlets (7) placed in a star formation on a frame (6) which moves horizontally forth and back along the whole length of the autoclave.



















A standard treatment cycle lasting about 20 to 30 minutes, is as follows:

A - An initial vacuum phase to remove all air from the wood pores.  

B – Treatment of items, with impregnant or finely atomised coating. During this phase the plant can operate both under constant vacuum or allowing air to enter to help the product penetrate deeply into the wood.

C - A series of changes of air inside the autoclave to facilitate dripping, drying and pacifying of the treated items.


This treatment guarantees:

- When using impregnants: An absorption/ penetration of 3 to 6 mm. In the white part.

- When using primer/finishing coats: A very high penetration and adherence level of the coating to the internal surface of the wood pores, a result that can only be achieved thanks to the vacuum.

The exceptional penetration and adherence of the primer is the only guarantee for a perfect and lasting resistance of the finishing coat, both if applied using the same plant or using other techniques.







Result guaranteed: thanks to the completely automatic operation of the machine, any possible human error is excluded, maximum respect of the environment

The vacuum pump, which sucks in the air in the autoclave, is the liquid ring type: it also uses water in a closed circuit. The impregnating and coating system operates in a perfectly hermetically closed autoclave that prevents any type of bad smell from exiting. Once the process has finished the product may be fully recovered by sending it back to the relative deposit. The water used for washing the air entering the plant will be continuously recycled and periodically it must be discharged and changed. During drying the water may contain polluted substances made up principally of chemical products used in the coating products. The autoclaves are built on the basis of the sizes of the items to be treated. The items exit the autoclave perfectly dry, treated or coated.