Patent No．ZL 02 2 34937.5
1．What is high frequency-vacuum combination drying?
High frequency vacuum Combination drying is in fact a technique based on high frequency heating and vacuum combination dehydration．High frequency heating can simultaneously heat timber both internally and externally despite timber dimension while vacuum combination dehydration reduces vaporization and enable desiccation of timber at lower temperature in good quality thus reducing drying time．
2．Technical process of high frequency-vacuum combination drying
Wood materials are loaded on vehicle in regular form and then transferred into vacuum chamber．Connect the output copper strip and ground wire of the generator respectively．Then close the vacuum chamber and reduce the inner pressure tO the status of relatie vacuum．Connect high frequency power supply and start heating both inside and outside of wood materials．Because the inner pressure is higher than surface pressure moisture is gradually shifting to the surface of wood materials and evaporated．Condensed on the cold plate and then discharged out of chamber regularly by vacuum pump，moisture content will them meet preset requirement．Intermittent heating can reduce power consumption but prolong heating time．Usually continuous heating is applied at initial stage and intermittent heating is used at closing period．Due to the low pressure inside chamber the drying temperature is normally lower than 70℃。
3．Application range for high frequency-vacuum combination drying
Electric tube self-oscillator is used in high-frequency generator．Therefore power consumption is the main cost for drying．This machine is mainly used for hard-to-dry wood and wood of larger cross section for drying is 500-600MM．For special occasion this machine is suitable for drying non-regular shape timber such as log and root．
Use：suitable for drying hard-to-dry wood and high-grade wood materials.
Main technical parameters：
1．Equipment composition：high frequency generator，vacuum combination chamber
material vehicle，track
2．Holding capacity of material vehicle：2M3-6M3 or user tailed-made．
3．Degree of vacuum combination：≤0.02Mpa
4．Drying temperature：≤70℃
5．Suitable wood：all hard-to-dr wood materials
6．Inital moisture content：< 24％(W/W)
7．Power of high frequency generator：(20KW)30KW
8．Frequency of high frequency generator：6～13.56MHZ
Maintechnical parameters:
Nothing
Shijiazhuang Development Zone Daxin Electronic Science and Technoogy Co., Ltd.
ADDD：No.6 Zhonghua South Street if Shijiazhuang TEL：(0311)83826140 13803339301 13803377301 FAX:(0311)83826140
