Effect of Pre-treating of High-temperature and Low-humidity on Prevention of Checks during RF/V Drying of Japanese cedar pillar

摘要

Introduction It was well known that the high-temperature and low-humidity pretreatrnent has excellent effect on prevention of checks during high-temperature kiln drying and air drying of heavy timber with pith. After the pre-treatrnent, however, internal checks occur during high-temperature kiln drying and air drying of it is a time consuming process. This study was carried out to investigate the effect of pre-treating of Japanese cedar pillar (15×15 cm in cross section and 360 cm in length) in dry bulb temperature 120℃ and wet bulb temperature 90℃ on drying time, prevention of surface checks and internal checks during radio-frequency/vacuum (RF/V) drying.