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Characteristic of particles created by preparatory operationsof the particleboard production process
Characteristic of particles created by preparatory operations of the particleboard production process.The production of wood-based panels, taking into account material innovations, involves the need to adjust the operation of technological devices to the properties of basic and auxiliary materials. In this study, it was decided to check the particle sizes after sorting raw materials representing 3 groups: forest biomass â pine branches, agricultural biomass - oilseed plant straw, and post-production material. Fractions were taken from the 2.00 mm mesh sieve of a sorter for the core layer of the particleboard and the fractional composition was determined by sieve analysis. The average linear particle dimensions and bulk density of each lignocellulosic raw material were also determined. Due to the varying proportions, it is necessary to adapt the parameters of the technological operations to the specifics of the raw material being processed or to introduce guidelines for the selection of particle sizes guided by their actual average size. Studies have shown differences between the individual materials. This is particularly important, as proper preparation of the raw material translates into the quality of the boards produced from them and the efficiency of the entire process.
Efficiency of integrated technological modules in mass production processes of wooden door frames
Energy Consumption for Furniture Joints during Drilling in Birch Plywood
The purpose of this study is to support eco-design ideas and sustainable manufacturing techniques by examining the energy consumption related to drilling holes for different furniture connections. The experimental model is a simple piece of furniture made from birch plywood with three different types of joints. Eccentric joints, confirmat screws, and dowel measurements of energy consumption with a CNC drilling and milling machine show different values for every kind of connector. The energy consumption was measured using a portable power quality analyzer, specifically the PQ-box 150 manufactured by A:Eberle GmbH & Co. KG NĂŒrnberg, Germany. This device likely adheres to industry standards for energy measurement, ensuring accurate and reliable results. The measurement process involved recording energy consumption at different stages of the machining process, allowing for the analysis of specific cutting work and total energy consumption for various joint types. Dowels exhibit the lowest energy consumption at 0.105 Wh for one furniture joint, confirmat screws at 0.127 Wh, while eccentric joints, despite their higher energy consumption (0.173 Wh), offer enhanced transportability and assembly flexibility of a piece of furniture. Specific cutting power for one selected piece of furniture was 227.89 J/mm3 for dowels, 190.63 J/mm3 for eccentric joints and 261.68 J/mm3 for confirmat screws.
Influence of thermal modification and sanding parameters on finest particle content in pinewood dust
Effect of Low-Thermal Treatment on the Particle Size Distribution in Wood Dust after Milling
The thermal treatment of wood can improve the appearance of the wood productâs surface, its dimensional stability, and resistance to fungal attacks. However, the heat treatment changes the technological properties of wood, making it a new engineering material. This work investigates the effect of the low-thermal treatment of birch wood (Betula pendula Roth.), European beech wood (Fagus sylvatica L.), and alder wood (Alnus glutinosa L.) on the fine dust particles creation during woodworking. The samples of thermally treated wood with temperatures commonly used for the change of wood colour (105, 125, and 135 °C) were compared with reference samples made of natural wood. All 12 variants of the tested woods were milled using the 5-axis CNC machining center (20 mm diamond cutter, rotational speed 18,000 rev·minâ1, the depth of cut 3 mm, feed rates of 2, 4 and 6 mâminâ1). A sieving analysis method allowed measuring the dust particle size distributions in all dust samples. The experimentâs result analysis points out that wood type, thermal treatment, and feed rate meaningfully affect the size distribution of dust particles. Compared to birch wood and beech wood, the milling of alder wood samples created a much higher content of the finest dust particles, with particle sizes smaller than 0.032 mm. Increased temperatures in thermal treatment increase the share of fine dust particles with sizes smaller than 0.125 mm, compared to wood in its natural state. Milling with a lower feed rate (2 m·minâ1) creates finer dust than processing with higher feed rates (4 and 6 m·minâ1). Generally, the milling of alder in a natural or thermally treated state is a source of fine dust particles, particularly at low feed speed-rate milling, compared to birch and beech wood. In general, these results indicate that the low temperature thermal treatment parameters attribute new technological properties to all thermally modified types of wood tested.
The influence of feed rate during pilot hole drilling on screw withdrawal resistance in particleboard
AbstractScrew withdrawal resistance (SWR) is a metric that assesses the strength of furniture joints made with wood screws. The SWR value is influenced by several factors, such as the size of the screw, the depth to which it is embedded, the diameter of the pilot hole, and the material properties of the furniture components that are being joined together. These factors have been widely studied in the scientific literature. The objective of the research was to investigate the previously unexplored factor of a feed rate during pilot hole drilling and its influence on SWR. This study used three particleboards composed of raw pine material and ureaâformaldehyde resins; the boards varied in average density (633, 637, and 714 kg/m3). Blind pilot holes with a diameter of 5 mm and depth of 25 mm were drilled in these boards using three significantly different feed rates (0.033, 0.33, and 3.33 mm/rev.). Subsequently, a confirmat-type furniture screw (7 mm major diameter, 4 mm minor diameter, 3 mm pitch) was screwed into these pilot holes. The ultimate SWR was measured with a universal testing machine. The results showed that the highest feed rate significantly decreases the SWR for all particleboards tested. This phenomenon can be attributed to the fact that a higher feed rate leads to a decreased precision in the internal surface of the pilot hole, consequently diminishing the screwâs anchoring capacity within the hole. The high feed rate, used to increase production efficiency, may significantly reduce furniture durability and usability.
Design and comparison of a suitable dust separation technique during the machining process in a CNC machining center
Design and comparison of a suitable separation technique during the machining process in a CNC machining center. The paper deals with the issue of chip extraction from the milling process in a CNC machining center. The paper aimed to compare the particle size distribution of dust generated in the milling process of natural wood (beech, oak, and spruce) and MDF on a 5-axis CNC machining center. The particle size distribution was evaluated using sieve analysis of samples from the total weight of the captured dust. The results showed that the processing of natural wood is mainly characterized by the formation of coarse dust fractions (2 mm - 1 mm sieves), while the processing of MDF was associated with the formation of fine dust fractions with a size below 100 ÎŒm. Another of the objectives was to compare the separation values on the fractional separation curves of selected mechanical separators and filters with the size distribution of dust particles and to propose a suitable separation technique that meets the criteria of "best available technique" (BAT) in the processing of natural wood and MDF, as well as to point out the creation of and the production of harmful dust fractions, which arise mainly during the processing of MDF. We intended to assess whether the introduction of the given technology with the given material mix will also require modifications on the side of the extraction device.
The effect of average chip thickness on the potentially respirable dust from CNC finish milling of wood-based materials
Milling wood-based materials on CNC devices causes the creation of chips in small sizes that may escape the chip extraction zone to the surrounding environment and pollute the air. The article studied the effect of the feed rate (vf) and the width of cut (ae), transformed into kinematic average chip thickness, on the amounts of chips in respirable sizes <10.0Όm created in the cutting zone from particleboards (PB) and medium-density fibreboards (MDF). The amounts of dust-sized chips are discussed and were determined by the sieving analysis. The sizes of potentially respirable chips were estimated by weighting with the laser diffraction method. The highest amounts of chips from PB were of 0.250-0.500 mm (38-41%w), but in MDF, amounts varied depending on cutting conditions. With (ae) 1 mm were in the size range of 0.125-0.250 mm (35-54%w), for (ae) 2 mm (33-35%w), and (ae) 3 mm (36-40%w) with combinations of (vf) 6-8 m·min-1. With a combination of (vf) 10 and 12 m·min-1 distribution moved to a higher size range. Chips in sizes 10.0-4.0 Όm were estimated by <1%, for 4.0-2.5 Όm <0.5%, in 2.5-0.1 Όm <0.3%, and <0.1 Όm by <0.05%. Statistically was proven (p<0.05) only in PB, with adjusted (ae) by 1 mm, increasing the value of (vf) from 6 to 12 m·min-1 and also with (vf) at 6 m·min-1, between values of (ae) 1 and 2 mm (hm of 0.025-0.035 mm), will significantly (p<0.05) lower the percentual amounts of chips in sizes 10.0-4.0 and 4.0-2.5 Όm.
The efficiency of the formatting and milling module of the technological line for door frames production
By introducing a new technological line for formatting and milling mass-customized door frames for wooden doors, PORTA KMI Poland with an industrial plant located in EĆk, Poland, conducted appropriate performance tests of the line to determine the production capacity during technological acceptance in order to check whether the assumed capacity was met before its technical acceptance takes place. The work describes how the processing time changes for frames with changed beam lengths from the reference length of 2028 mm to 2600 mm and for frames whose width has been increased from 127 and 147 mm to 500 mm. On this basis, an average time of 25.53 s was calculated for door frames with beams 2600 mm long and 28.1 s for door frames with a width of 500 mm. Efficiency was also calculated, which is 2.35 for frames with a changed beam length of 2.14.
Long-term operation of pulse-jet filters for wood dust
Long-term operation of pulse-jet filters for wood dust. The study specifies the value of flow resistance and separation efficiency of filter material during long-term use in pulse-jet filters for wood dust. The experiments were carried out for one type of material working in two different filtration installations in one furniture factory. The bags were obtained from the installations after working for 67, 133 and 272 days, respectively. All tests were performed on the pilot-scale test stand under identical filtration conditions. Studies have shown that long-term filter material use increases airflow resistance and improves filtration efficiency. The range of these changes depends on the operating conditions of the pulse-jet filters. The obtained results made it possible to determine the properties of the long-term use of filter materials in various filtration conditions.
Development and characterization of novel particleboard panels manufactured from organic waste with fiberglass reinforcement
Improving the stiffness of the corner connections in wooden door frames
The research aimed to determine the strength and stiffness of corner joints in interior door frames, depending on their construction and the modifications made to the design of the door frame joints. Initially, two models were compared: model 1, with two connectors using a clamping screw at an angle of 45°, and model 0, with a single connector using a cam joint at an angle of 90°. In all tests, model 1 exhibited significantly better mechanical properties. To improve the performance of model 0, three alternative construction models (A, B, and C) were proposed by changing the position of the door frame mounting holes. In the compression test, model A showed an increased bending moment compared to model 0, while models B and C showed no such improvement. In the tension test, the bending moment values remained at a similar level across all construction variants, including model 0. In terms of bending moment, the best result in compression was achieved by model A (48.26âŻNm), and in tension by model B (48.72âŻNm). The highest stiffness was demonstrated by model 1 (up to 42.38âŻkNm/rad), while among the alternative models, model C showed the best result in tension (33.98âŻkNm/rad). Due to the favourable increase in bending moment under compression in model A and the insignificant changes under tension across all variants, model A is considered the optimal solution. To enhance the strength of the door frame, offset holes can be applied as proposed in this model.
The effect of operational parameters on the size of chips in the finishing wood-based materials by milling
The effect of operational parameters on the creation of chip particles in the CNC finishing processingof wood-based materials. The object of this study was a comparison of created chips from the process of milling two wood-based materials: medium-density fiberboard, and particleboard, using a modern CNC 5-axis milling center. The materials in the form of blocks were milled at constant revolutions of the cutting tool (18,000 rev/min), with changeable variables of feed rates (8, 10, and 12 m/min), and width of cut (1, 2, and 3 mm). The size of created chips was measured by gravimetric weighing from sieving analysis of the retained volume of chips on sieves with pre-defined mesh sizes. The main emphasis was aimed at studying particles of chipsobtained in the finishing process of the milling below <0.125mm. However, the others are mentioned and discussed. Gravimetric differences of the retained volume of chip mass show that created MDF chips are mostly in the size range of <0.250 to 0.125 mm, and particleboard in the size range of <0.500 to 0.250 mm. Distribution of average values in dependence on different conditions shows a decreasing effect with increasing feed rate on the amount of very small chip particles in the volume of both materials. Increasing the feed rate can decrease the amount of very particles in the range below <0.125 mm in the volume of chip mass.
Charcoal Briquette Manufactured from Indonesian Sugar Palm Bunches (Arenga longipes Mogea) as Biomass-Based New Renewable Energy
The prospect of using retro timber in the furniture industry
The prospect of using retrowood in the furniture industry. To avoid over-consumption of natural resources, the idea of recycling or extending the life of wood-based materials is often considered in recent times.Therefore, it seems appropriate to conduct research aimed at studying the mechanical properties of retrowood and determining the possibility of its application. As part of a scientific study, surveys of old wooden residential buildings (ĐĐžĐșĐžŃĐžĐœĐ° et al., 2017) of the Russian North with a service life of 60â100 years and mechanical tests of both retrowood and freshly cut wood were carried out. Comparison of indicators of physical and mechanical properties of old wood and new wood material used in the manufacture of furniture with normative indicators of properties was made. Based on the research results, an assessment was made of the possibility of reusing retrowood in the production of furniture and interior elements. Well-preserved vintage wood from old wooden houses being demolished is a potential resource-saving raw material for making furniture, which is confirmed by testing the properties of this material. Based on the research results, the possibility of designing and manufacturing furniture and interior elements from retro wood is considered.
