Subject of research – the use of post-consumer wood (PCW) in woodworking industry. The objective is to develop a scientific and technical basis for the use of post-consumer wood in the production of structural materials, in particular, standard and combined blockboards (BB) with predictable characteristics, for application in woodworking processes, furniture making and manufacturing other wood products. Research methods: physical, mechanical, mathematical planning of experiments, sorting, cleaning, flat pressing, direct and balancing transformation, mathematical modeling, finite elements, fuzzy set theory, randomization, system analysis, mathematical statistics. Scientific novelty: First developed: fuzzy expert system of decision-making support for choosing a rational option for PCW sorting; mathematical model for calculating the depth of cutting by needle cutters, which allows predicting the thickness of the contaminated surface layer removal; a heuristic model of organizing the search for a rational variant of PCW processing which ensures the choice of an efficient method of cutting; mathematical models for predicting the basic characteristics of standard PCW-made blockboards: cross-breaking strength, shear strength and shape stability depending on the transverse dimensions of the strips, the angle of annual rings slope to the blockboard face, and the age of the PCW; mathematical model of deformability of combined PCW-made BB with alternating laying of strips from solid wood and from chipboard, the use of which provides prediction of shape stability; mathematical model for calculating the potential PCW volume; mathematical model for calculating the economic efficiency of processing PCW into blanks. Improved: systematization of PCW and its belonging to a certain category according to the degree of contamination, which allowed the development of the PCW classifier; design of standard and combined PCW-made BB; technology of material processing of PCW, in particular, in the operations of sorting, cutting and cleaning, which increases the resource efficiency and increases the volume of production of dimensional-suitable blanks for PCW assortment. Received further development: research of physico-mechanical properties of fir-tree PCW of various ages; methodology and concept of using PCW in woodworking technologies. Practical value: The results of studies of physico-mechanical properties of fir-tree PCW of different ages made it possible to understand the dynamics of these indicators, to fill the normative database. The developed technology of PCW cleaning and the proposed mathematical model of the depth of cutting with needle cutters can be used for surface cleaning processes under production conditions.
Substantiation and selection of strip characteristics for PCW-made BB is crucial for design engineering and prediction of physical and mechanical parameters. The developed software for the parameterization of the construction of PCW-made blockboards will help to automate the study of the deformability of combined BBs depending on the power and technological loads and on-line selection of the design from the existing range of PCW. The implementation of the developed mathematical model for calculating the potential and balance of PCW will make it possible to promptly carry out accounting and the quantitative potential of PCW and effectively predict the distribution of PCW for processing. The developed PCW classifier with a list of classification groups will allow you to effectively sort by the rules of identification. The priority of the obtained results is confirmed by four patents of Ukraine on useful models on the methods of manufacturing panel-form materials from PCW. The research results are implemented in the form of practical recommendations for technological processes for the manufacture of products and elements of products from PCW, which is indicated in the relevant acts. The industry is woodworking.
