In design, besides using logs directly, timber is processed into planks, squares, or other products.
To reduce deformation and cracking during use, planks and squares typically undergo natural or artificial drying. Natural drying involves air-drying stacked timber. Artificial drying primarily uses kiln drying, but simpler baking or roasting methods can also be used.
A kiln drying chamber is a drying room equipped with circulating air equipment, capable of regulating and controlling air temperature and humidity. Timber dried in a kiln is of high quality, with a moisture content below 10%.
Timber prone to decay should undergo pre-treatment with preservatives. Gluing methods can be used to bond planks into large components for timber structures, piles, etc. Timber can also be processed into plywood, particleboard, fiberboard, etc.
Timber is susceptible to swelling and shrinking due to air humidity, which can cause timber products to become damp and soon decay and be damaged. Therefore, timber drying technology was developed. Timber drying is a process that uses heating and the pressure difference between the internal and external water vapor in the wood to reduce its moisture content to a suitable value.
It is an indispensable production link in the timber industry. The purpose of wood drying is to: reduce weight, saving labor and costs in transportation; prevent insects and rot, extending service life; prevent deformation and warping, increasing elasticity, and thus improving the quality of wood products.
Increasing the drying speed while ensuring drying quality is the fundamental principle of drying. The quality requirements for drying are: the final moisture content and uniformity of the dried wood must meet the requirements of the processing technology; the integrity of the wood must be maintained, without defects unacceptable by process specifications, and the inherent properties of the wood products must not be altered.
