A investigation of form of stability of variously designed furniture board made of pine wood of different constructions

Abstract

It is substantiated that the natural wood of pin species in a massive form, in particular defect-free pieces of pine wood, is a suitable resource for the manufacture of furniture boards, since glued structures with the correct arrangement of rails have stable internal stresses, which positively affects dimensional stability – a stressed-deformed state during manufacture and operation of products. The regularities of the effect of the width of the slats and the angle of inclination of the annual layers in furniture boards with alternate laying of radial (the angle of inclination of the annual rings in the cross section of the bars 61-90 degrees) and tangential (the angle of inclination of the annual rings in the cross section of the bars 1-30 degrees) on the dimensional stability of the combined furniture boards made of coniferous wood, in particular Scots pine (Pinus sylvestris). Based on the results of experimental studies, an adequate regression equation of the second order was obtained, using the B-plan, to determine the arrow of the deflection of glued shields, depending on the width of the blanks and the angle of inclination of the annual layers in the rails, which are alternately placed in the structure. The best quality in terms of shape stability (shape stability) will be combined furniture boards made of Scots pine wood (Pinus sylvestris): Brad = 20 mm; Btan = 20 mm, when deviations from flatness are 0.064 mm. The dimensional stability of furniture boards made of studded wood is significantly affected by the width of the tangential rails. It was determined that when laying a radial rail with a width of 80 mm, the tangential rail cannot be wider than 60 mm, since the value of the arrow deflection from flatness will be greater than the standard value, i.e. 0.3 mm for the width of furniture boards up to 500 mm. It has been established that to ensure the dimensional stability of furniture panels made of soft wood, in particular Scots pine (Pinus sylvestris) with combined installation (radial-tangential slats), it is desirable to use a 1:3 aspect ratio in the cross section of the slats, i.e. for furniture panels with a thickness of 20 mm, the width of the slats should not exceed 60 mm. Practical recommendations have been developed for the production of furniture panels from coniferous wood, in particular Scots pine.