A novel method for producing a glulam from the wood of peeler cores

This study presents an opportunity for rational utilization of poplar wood peeler cores in the production of glued laminated timber (glulam) beams. An approach for optimal use of small-diameter raw material with a circular cross-section is also proposed in order to obtain a final product in a significantly high quantitative yield. The applied novel method of sawing the peeler cores and subsequent combination of gluing the obtained lamellas allows to achieve: reduction of labor and energy consumption in the processing; rational utilization of this waste raw material; obtaining a product sought by consumers; opportunity to implement technology for the production of glulam from peeler cores. The results showed that sawing the peeler cores and obtaining lamellas with a trapezoidal cross-section leads to a high quantitative yield of 76,3 %. The final quantitative yield in subsequent technological operations in the manufacturing of engineered wood of glulam type reaches 48,8 % of the volume of  raw material. In addition, equations have been working are used for the determination of the most suitable sizes of the lamellas, depending on the diameter and the kerf width

Iskorištavanje borovine (Pinus sylvestris L.) s greškama za proizvodnju kompozitnog drva

This study presents opportunities for the utilization of timber by-products with defects for manufacturing engineered wood panels. Three gluing methods were proposed for this waste raw material derived from Scots pine (Pinus sylvestris L.) wood. The methods used for combining and gluing enabled a more complete and complex utilization of wood with defects. The physical properties (density and moisture content) and mechanical properties (bending strength and modulus of elasticity) of the laboratory-fabricated engineered wood panels were evaluated in accordance with the European standards. The highest density of 643 kg/m3 and bending strength values (28.6 N/mm2) were obtained from the panels manufactured using method 3 and veneered with beech veneer sheets. The modulus of elasticity of the laboratory-made engineered wood panels reached values of up to 5580 N/mm2. This study demonstrated the feasibility of the utilization of defective wood pieces in the manufacturing of engineered wood panels.U radu je predstavljena mogućnost iskorištavanja otpadnog drva s greškama za proizvodnju kompozitnog drva u graditeljstvu. Predložene su tri metode lijepljenja otpadnog drva borovine (Pinus sylvestris L.). Metode kombiniranja i lijepljenja omogućile su potpunije iskorištavanje drva s greškama. Fizička svojstva (gustoća i sadržaj vode) i mehanička svojstva (čvrstoća na savijanje i modul elastičnosti) laboratorijski proizvedenih kompozitnih drvnih ploča za graditeljstvo ocijenjena su prema europskim standardima. Najveću gustoću (643 kg/m3) i čvrstoću na savijanje (28,6 N/mm2) imale su ploče proizvedene metodom 3 i furnirane bukovim furnirom. Modul elastičnosti laboratorijski proizvedenih kompozitnih drvnih ploča za graditeljstvo dosegnuo je vrijednost od 5580 N/mm2. Ovo je istraživanje uputilo na mogućnost iskorištavanja drva s greškama za proizvodnju kompozitnih drvnih ploča namijenjenih graditeljstvu

Utilization of peeler cores for producing beams with hollow cross-section

This study presents an opportunity to utilize peeler cores derived from poplar wood for the production of hollow beams. In this way, final products to meet the needs of consumers can be obtained. The proposed novel methods for sawing and gluing the produced materials allow rational application of the waste raw material in the plywood manufacturing. Another advantage in this case is that products with a square cross-section with dimensions close to or corresponding to the standard ones are obtained from small-diameter round wood. The raw material used to receive the proposed hollow beams is up to 33% less than a conventional beam with the same dimensions. The manufactured products are lighter and with a significantly stable cross-sectional shape, compared to natural wood beams with the same dimensions. Sawing the peeler cores and obtaining materials with a triangular and trapezoidal cross-section helps to achieve volume yields from 60.6% to 71.1% of the raw material initial volume