进行米老排(Mytilaria laosensis)锯材干燥中试,验证中试干燥基准的正确性,以求获得适于米老排生产应用的干燥基准.采用生产中广泛使用的强制气流循环普通干燥窑,在给定的中试干燥基准下对米老排锯材实施中级干燥试验,并按照国家标准(GB/T 6491-1999)进行锯材干燥质量评定.试验结果表明:米老排锯材干燥产品的平均终含水率7.5％;厚度含水率偏差为0.91％;应力指标4.06％;平均顺弯度为0.36％,横弯度为0.14％;扭曲度为0.29％;瓦弯度为2.54％;纵裂度为4.79％;截面收缩率为0.19％;无内裂.干燥至含水率12％时所用时间为224 h(9.33 d);干燥速度为0.36％·h-1.锯材总体干燥质量等级为二级,达到木制品生产对米老排锯材干燥质量的要求.%A pilot-scale test on the drying of the sawn timber of Mytilaria laosensis was carried out to examine the accuracy of the Chinese drying schedule. A widely applied drying kiln with a forced air circulation system was adopted to implement intermediate level drying with a given test drying schedule. The quality of the dried sawn timber was evaluated according to national standard (GB/T 6491-1999). The related parameters of the dried M. laosensis sawn timber were as follows: average final moisture content; 7. 5%; thickness moisture deviation: 0. 91%; stress index: 4. 06%; average longitudinal bending degree: 0. 36%; lateral bending degree: 0. 14%; distortion degree; 0. 29%; tile shape bending degree: 2. 54%; longitudinal cracking degree: 4. 79%; cross section shrinkage rate: 0. 19%. No internal crack was observed. The time of drying to a water content of 12% was 224 h (9. 33 d); drying speed was 0. 36% · h"1. The overall drying quality of sawn timber achieved grade two, indicating that the quality of M. laosensis sawn timber after drying could meet the production requirements.
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