Wood furniture drying with constant temperature and dehumidification method:
Generally speaking, there are three drying steps for wood funiture and its raw materials: Raw material drying, semi-finished product drying and finished product drying.
1. Raw material drying:
The moisture inside the wood should be discharged by fumigation or high temperature drying method in order to reduce the moisture content to no more than 10% to 12%. The national moisture content standard is 12%.
Those wood blocks we bought are imported from abroad and have been done drying treatment before leaving factory. Why do we still need to dry them again? This is because there are much water vapor in the air, especially for southern areas whose humidity is very high. During transportation and storage process, there will be plenty of water vapor entering into the wood. Therefore, we need do secondary drying process on those wood blocks in order to contol the humidity within the specified standard.
2. Semi-finished product drying:
The reason why the semi- finished product also need drying is the same as the above reason, namely, there will be plenty of water vapor entering into the wood during transportation and storage process. Those wood blocks should be trimmed into chair or table legs with different sizes and shapes according to different product drawings. Afterwards, transport them into the drying room for third time drying process and control its humidity within 10 %RH.
3. Finished product drying:
After semi- finished product drying, they will be assembled which will take eight or ten days. During this time, there will be a small amount of water vapor entering into the finished product as well. Therefore, there should be the last time drying process which is a little bit different from the above two steps. Because this time the drying object is a whole piece of furniture, such as a chair, a cabinet or a table, which can not be fumigated. ( Because the assembled furniture will be likely processed with glue, which can not contact with water if it is not dry) The finished product only can be dried with constant temperature and constant humidity, namely the temperature should be between 45℃ and 65℃ and the humidity should be between 30- 60%RH. Generally speaking, the drying time should be 24 to 48 hours until the wood furniture humidity reaches within 8- 10 %RH. This is the last drying process for wood furniture.
Last but not the least, the wood furniture should be processed with grinding and painting. Only after it is painted, the external water vapor can not enter into the wood. As a result, the wood furniture humidity can be controlled within specified range and the problems of crack and deformation will also be effectively controlled.