Abstract
This study investigated the effect of pretreatment with high temperature and low humidity (HT-LH) on characteristics of radio-frequency/vacuum (RF/V) drying of boxed heart timber of Japanese cedar (150 × 150 mm in cross section, 3600 mm long). From green to approximately 15% moisture content, the drying times including HT-LH treatment were 170 h for the nonkerfed control, 190 h for the kerfed control, and 150 h for both the kerfed and nonkerfed HT-LH specimens. Surface checks were effectively prevented by the HT-LH treatment while the kerfed HT-LH specimens were free from surface checks. In order to prevent the formation of internal checking during RF/V drying, it is suggested that HT-LH treatment should finish around the fiber saturation point.
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Harris RA, Taras MA (1984) Comparison of moisture content distribution, stress distribution and shrinkage of red oak lumber dried by a radio-frequency/vacuum drying process and a conventional kiln. Forest Prod J 34:44–54
Kanagawa Y (1989) Resin distribution in lumber dried by vacuum drying combined with radio-frequency. Proceedings of the IUFRO International Wood Drying Symposium, Seattle, Washington, USA, pp 158–163
Avramidis S, Liu F, Neilson BJ (1994) Radio-frequency/vacuum drying of softwood: drying of thick western red cedar with constant electrode voltage. Forest Prod J 44:41–47
Lee NH, Luo JY (2002) Effect of steam explosion treatments on drying rates and moisture distributions during radio-frequency/vacuum drying of larch pillar combined with a longitudinal kerf. J Wood Sci 48:270–276
Tokumoto M, Takeda T, Yoshida T (2005) Effect of subsequent kiln-schedule after the high-temperature setting treatment on internal stresses of sugi boxed-heart timber without back-splittings (in Japanese). J Soc Mater Sci Jpn 54:365–370
Katagiri Y, Fujimoto N, Murase Y (2007) Effect of the treatment temperature on the surface drying set of sugi boxed-heart square timber. Drying Technol 25:507–510
Evans PD, Wingate-Hill R, Barry SC (2000) The effects of different kerfing and center-boring treatments on the checking of ACQ treated pine posts exposed to the weather. Forest Prod J 50:59–64
Fujimoto N, Fujimoito H, Kawabe J, Mataki Y (1994) Drying of boxed heart square timbers I. Changes of surface stress and cross-sectional shrinkage of dehumidifier kiln-dried timbers of sugi (in Japanese). Mokuzai Gakkaishi 40:758–765
Li C, Lee NH (2004) Effect of compressive load on shrinkage of larch blocks under radio-frequency/vacuum heating. Wood Fiber Sci 36:9–16
Lee NH, Hayashi K, Jung HS (1998) Effect of radio-frequency/vacuum drying and mechanical press-drying on shrinkage and checking of walnut log cross sections. Forest Prod J 48:73–79
Yoshida T, Hashizume T, Fujimoto N (2000) High-temperature drying characteristics on boxed-heart square timber of karamatsu and sugi - influences of high temperature conditions with low humidity on drying properties (in Japanese). Mokuzai Kogyo 55:357–362
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Lee, NH., Li, C., Zhao, XF. et al. Effect of pretreatment with high temperature and low humidity on drying time and prevention of checking during radio-frequency/vacuum drying of Japanese cedar pillar. J Wood Sci 56, 19–24 (2010). https://doi.org/10.1007/s10086-009-1050-4
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DOI: https://doi.org/10.1007/s10086-009-1050-4