In the world of the woodworking industry, one of the stages in the production process is wood drying or what is called an oven. Basically, there are two types of oven or wood drying, namely naturally and using machines. Natural oven drying is wood directly in the sun, while machine oven is wood drying using a tool in the form of an oven. The term kiln dry is certainly not a foreign thing in the wood industry, considering the wood drying process itself is often known as kiln dry. Kiln dry is the process of reducing and removing the moisture content in the wood until it reaches the right MC (moisture content). This is because wood is a material that can change shape and size. The shape and size are in accordance with the MC, the size of the MC is the determining factor whether the wood is qualified or not for use as furniture, construction, or other woodworking needs.
Kiln dry is a special room designed in such a way to dry wood. In the room there is a tool used for the wood drying process. The way it works is that the boiler outside the chamber which produces hot steam is transmitted into the chamber which contains a pile of wooden planks with the help of a fan that is turned on. Then the hot steam inside moves into and out of the chamber according to the rhythm of the air flow carried by the fan. When wood is exposed to hot temperatures, wood will sweat and release the moisture content in it. Thus, the air condition around the wood becomes very humid. This moist air will be carried by a fan that points outwards. This process runs in stages according to the program or settings set by the operator. The length of the kiln dry process itself is 3 weeks to 4 weeks, until the moisture content released from the wood is considered sufficient.
Wood dryness or moisture indicators differ based on need. The MC standard of good wood so that it can be processed as a furniture material is 8-12%. The smaller the MC content, the smaller the wood size, because the moisture content in the wood has shrunk from the kiln dry process so that it affects the shape and size of the wood. The right moisture content in this wood is very important considering that the wood that is still wet will certainly have an effect on the finished furniture product. Wood that is too dry later can have the potential to crack or break, but wet wood is a disaster for one day. The reason is, the use of wet wood as furniture material will cause several things that cannot be avoided or in the sense that if you choose to use wet wood, you have to accept the consequences in the future. Among them are, wood can become powdery, condense, moldy, and the worst thing will rot faster.
The things that must be considered when the kiln dry process are
- Oven heat level or temperature
The temperature that is set in such a way should not be directly on the hottest size, but gradually from warm, medium, then hot. This is because the distribution of hot steam can only be done after the kiln dry door is closed. In addition, drying at a sudden high temperature will cause the moisture to be forced out too quickly which can potentially cause a fire
- Arrangement of wooden slabs in chamber
In the process of drying wood with a kiln dry, a neat arrangement of boards and a good arrangement provides an even heat effect. So that air circulation becomes smooth, which ultimately makes the wood dry optimally and perfectly.
- Selection of the right drug
When drying wood, the process that takes place before the oven in the chamber is turned on is drug spraying. This drug is an anti-fungal and termite drug, so the selection of the right drug can produce good quality boards after the kiln dry process is complete
- The door must be closed during the oven process
The goal is to continue to maintain a stable temperature in the chamber or kiln dry room, so that the flow of hot steam in the chamber becomes constant and does not disappear
During the oven process, it doesn’t have to be guarded 24 hours, it’s just that it would be better to prevent things that are not desirable so that consistently checking the temperature regulation program is a wise action to monitor the progress of the kiln dry process on a regular basis. In addition to keeping the furnace or boiler on, it is also important to check the control of air temperature, humidity and wood MC
That was a brief information about the kiln dry oven process, hopefully it will be useful and leave a comment to be able to discuss further.