DESDOBRO DE Eucalyptus grandis Hill ex Maiden VISANDO A DIMINUIR O EFEITO DAS TENSÕES DE CRESCIMENTO
DOI:
https://doi.org/10.24278/2178-5031.199132209Keywords:
sawmill, growth stress, end-splitting, Eucelyptus grandisAbstract
In order to reduce the effect of growth stresses causing splitting in the wood during sawing operation, logs of E. grandis were sawed using two methods. In the first, logs were brokendown by the cant method, through two symmetrical simultaneous cuts. Each cut was at a third of the ray from the periphery, done with a twin band saw, fed by end dogging device. The cants were resawed at the same saw, through symmetrical sucessive cuts, after turning the log 90 degrees. Cuts started from the periphery to the center of the cant, producing boards of 25 mm thick. In the second method, the logs were brokendown using a band saw with log carriage, through parallel alternate cuts, from the periphery to the center, producing boards of the same thickness. This method is known as live sawing. In the cant method, green boards showed splitting index about nine times smaller than that of the live sawing method. After seasoning, the splitting index was about five times smaIler in the cant method than in the live sawing method. It was also verified a high variability among trees in the splitting intensity character.
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References
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