Estimating the Moisture Content of Lumber During the Drying Process

The moisture centent of lumber during drying is usually estimated based on data obtained from kiln samples. This has a number of drawbacks: moisture content varies within each board, as well as between boards, drying rate varies, and errors are made in weighing and computation. In drying redwood it is statistically calculated that information based on 12 samples gives a high degree of assurance that the average moisture content of the lot is within 10.8 percent of the average moisture content of the samples. If, instead, six or two samples are used, the difference between the average moisture content of the lot and that of samples could be as much as 15.9 percent and 38 percent, respectively. It is expensive to employ a large number of kiln samples for close approximation of the moisture content of the charge. An alternative which has been shown to be promising is a method based on moisture content estimates obtained from unit weight. This indicates that weight data from an entire lot of lumber may provide a basis for estimating the moisture content of the lumber more accurately than economically possible by the limited sampling method currently in use.

You must be logged in to download any documents. Please login (login accounts are free) or learn how to Become a Member