The raw materials used by Masonite’s chip boards come from the forest via sawmills. The timber is transported from the forest to the sawmills.
When the timber has been barked part is sawn as wood and the rest goes to large chippers which cuts the timber to chips. Chips, sawdust and cutter shavings are delivered to Masonite. The chips and some of the sawdust then go down into the chip cannons where the chips under high pressure and high heat are comminuted into long fibres. The by-products such as bark and other residual products are used as fuel for the boilers that feed the cannons and the rest of the manufacturing process with steam.
The mass is taken further from the cannons to attrition mill where the pulp is ground. After that the pulp concentration is regulated and help chemicals and resin is added. The pulp is now ready to be made into wood fibre board.
The fibres are transported to a forming machine where a wet mat is formed in an even layer. The wet mat is pressed between cylinders in order to remove excessive water. The mat is then cut into sheets 24ft long.
The conveyor belt, which moves at a speed of 35-40 metres/minute, leads to a press where the boards are stacked, and then loaded into the 30 press pockets. In the press the boards are pressed at high pressure and temperature for 5-25 minutes depending on quality.
After pressing the board proceeds to trimming and one of the many quality controls and in some cases to an oil bath for impregnation.
At this point in production the boards are very dry and easily warp and become crooked. To avoid this, the boards pass through two large drums. In the first drum the boards are hot-set at a temperature of about 160°C for about 8 hours. In the other drum the boards are conditioned to moisture equilibrium at a temperature of about 80°C.
After further controls and sorting the boards proceed to size sawing and possibly to further finishing. The process of turning chips into finished board takes, depending on the product, about 16 hours.
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