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Internal log scanning: Research to reality

Informally Refereed
Authors: Daniel L. Schmoldt
Year: 2000
Type: Scientific Journal
Station: Southern Research Station
Source: Proceedings of the Twenty-eighth Annual Hardwood Symposium


Improved log breakdown into lumber has been an active research topic since the 1960's. Demonstrated economic gains have driven the search for a cost-effective method to scan logs internally, from which it is assumed one can chose a better breakdown strategy. X-ray computed tomography (CT) has been widely accepted as the most promising internal imaging technique. Six design and operational constraints needed to be satisfied, however, for industrial CT of logs to become a viable reality. These are aperture size and reconstruction circle, scanning speed, scanner duty cycle, harsh industrial environments, radiation safety, and effective application sofiware. Current airport security scanners have achieved those goals and have bridged the gap between medical CT applications and industrial CT. The log scanning application has numerous similarities with the explosive detection application, which points to a relatively straightforward transition. A recent mill test of CT log scanning validates the value gains that can be realized. In some cases, those gains may become more pronounced in later processing stages. However, upstream sorting and product allocation can also lead to better resource use and an improved bottom line.


Schmoldt, Daniel L. 2000. Internal log scanning: Research to reality. Proceedings of the Twenty-eighth Annual Hardwood Symposium