Friction correction when predicting wood basic density using drilling resistance
Year: 2020
Type: article
Abstract: Basic density is a fundamental wood property of pulp and sawn wood. An IML Resi PD 400 drilling resistance tool (IML System GmbH, Wiesloch, Germany) was used to evaluate the basic density of Eucalyptus nitens discs and the impact of needle friction on basic density prediction. To determine the accuracy of that prediction with the commonly used linear drill bit shaft friction correction and determine whether this correction is linear, 40 discs were drilled radially, then cut into segments which were measured for basic density. Drilling resistance had a strong relationship with basic density in the outer wood; it was weaker at the pith but this did not compromise prediction accuracy. When using a linear friction correction, the drilling resistance underpredicts basic density by 7.6% in the first 2–3 cm after stem entry, after which the prediction error ranged from 0.6–1.9%. The friction correction was found to be nonlinear, especially at the first few centimeters. To apply this friction correction, basic density values from the model should be added to predict basic density values until 2.9 cm from Resi entry point and after that subtracted to account for the drill bit shaft friction.
Source: Holzforschung
DOI: 10.1515/hf-2020-0156
Authors: Vilius Gendvilas, Geoffrey M. Downes, Mark Neyland, Mark Hunt, Andrew Jacobs, Julianne O’Reilly-Wapstra
Institution: University of Tasmania
Language: English
Subfield: Building and Construction
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3097669495