bioresources. com
PEER-REVIEWED ARTICLE
as per the EN 300 standard (2006), even for their longer axis, irrespective of the sampling direction. Moreover, the coefficient of orientation for these boards is only 1.14, which means they can be used without paying attention to the chip orientation. Another advantage of the MFP board is their smooth surface that, after light sanding, may be finished with melamine foil, making the boards highly suitable for formworks. Mechanical properties of industrial OSB are often much better than what is required by the EN 300 (2006) standard (Derkowski et al. 2014). This means there is a room for solutions improving both the economic aspect and the scope of the OSB use. A possible solution for improving functional quality of OSB is to give up on the orientation and manufacture unoriented strand board (USB) (Haute Innovation 2016). Unoriented strand board, manufactured by the Egger Company and Büsgen Institute of the University of Göttingen from soft wood of deciduous trees (birch, poplar, willow, alder), exhibited better mechanical properties and emitted less volatile organic compounds (VOC) than a pine- based OSB (Roffael et al. 2006). This paper evaluated the possibility of producing OSB with external layers made of non-strand chips which due to their properties will be able to replace traditional OSB in their construction applications. EXPERIMENTAL The study involved laboratory-manufactured three-layer boards with the core layer made of industrial strand chips intended for the internal layer of OSB panels. The external layers were made of microchips, fine chips, average chips, long chips, and strand chips from pine ( Pinus sylvestris (L.)) (Table 1). The chips were glued with pMDI (Bayer, Fribourg, Switzerland) and therefore the reference boards were industrial OSB/3 (OSB) glued in both layers with the same adhesive. Table 1. Chips used in OSB panels Type of Chip Abbreviation Description Microchips AA industrial chips intended for external layers of furniture particle boards Fine Chips BB
subscreen fraction obtained by screening industrial chips intended for the manufacture of OSB on a screen with 10 × 10 mm mesh and grinding in a laboratory mill industrial chips intended for the core layer of furniture particle boards fraction retained on a screen with 10 × 10 mm mesh and passing through 15 × 15 mm mesh during screening of industrial chips intended for the manufacture of OSB fraction retained on a screen with 15 × 15 mm mesh during screening of industrial chips intended for the manufacture of OSB
Average Chips
CC
Long Chips
DD
Strand Chips
EE
The fractional composition, linear dimensions, slenderness ( l / t ), width coefficient ( l / w ), flatness ( w / t ), and specific weight (Fw) of chips were investigated. Specific weight is defined in Eq. 1,
¨ © § 2 1 1 1 t l w * * * 0 U
¸ ¹ ·
(1)
F w
8345
Mirski et al . (2016). “Non - strand chips OSB,” B io R esources 11(4), 8344-8354.
Made with FlippingBook Annual report maker