1.During the whole process from the beginning to the end of drying, the kiln is full of saturated superheated steam of which the highest temperature is 150℃. This ensure that the wood surface does not crack, at the same time, increase the wood surface humidity, reduce the moisture difference between the wood inside and the outside. What’s more, because of the high steam temperature, the temperature of the wood core can be raised fast. It takes only 20 hours for the 15cm diameter log to get the temperature of wood core at 80℃, which creates the best conditions for drying wood core material.
2.The characteristic of the vacuum drying is that under the condition of negative pressure, the boiling point of water is reduced.While it’s -0.6MPa, the boiling point of water is 80 degrees Celsius. The moisture of wood core material can be rapidly extracted from inside , which is 3-6 times efficiency of the conventional drying.
3.The characteristics of wet steam drying is that wood in a high temperature and humidity environment, can reach the temperature range that can not be reached by conventional drying, and when the ambient temperature of wood reaches more than 100℃, wood moisture will become moisture extracting instead of moisture absorbing, wood moisture will be extracted naturally.And in the high temperature situation, wood also can be degreased .
4.Vacuum drying and wet steaming drying are carried out alternately to make wood appear a state of "moisture extracting - moisture absorbing - moisture extracting" reciprocating cycle, which will completely remove wood internal stress, balance wood moisture content, prevent different moisture content so that to avoid warping, deformation and other problems.
5.High temperature heat treatment, using saturated steam as protective steam, and constantly increasing the temperature in the kiln to reach the temperature required for heat treatment. In this temperature range, the wood surface solidifies, and the water absorption factors inside the wood decompose, so as to achieve the characteristics of wood stability.
1. The most high-end all-in-one machine, three modes（Vacuum drying, wet steam drying, micro carbonizing） can be adjusted according to the needs of the process.
2. Compared with the high-frequency type, there is no need to fill the kiln and no need to assure the wood shape is regular. Once there is a gap in the high-frequency machine, the moisture of the wood will be uneven. This vacuum type no need to worry about this matter.
3. High frequency machine while drying hard wood is easy to appear cracking, this machine is especially suitable for rare hard rosewood and other hard wood.
|Max. piling volume||6 cbm|
|Overall Dimensions||5.5m *2.5m*2.6m|
|Kiln inside size||1.8m*4.7m|
|Kiln body material||Rock wool /High strength steel plate|
|Thickness of insulation layer||5cm|
|Heating mode||Electric heating|
|Steam generator power||6-9kw|
|Circulation fan||High temperature resistant positive and reverse rotating motor|
|vacuum pumps quantity||1|
|Control system||Fully automatic PLC control|
|Suitable material||Irregularly shaped softwood and hardwood|
|Drying cycle||Wood below 5cm 5daysWood above 5cm 7days|
|Expansion coefficient of wood||One over one thousand|