Faculty of Design and Technologies of Furniture and Interior
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Item type:Publication, Analysis of the influence of the length of beech sawlogs (Fagus sylvatica L.) on the maximum quantity exploitation(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2021-09); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Wood waste in the sawmill industry of wood processing(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2023-09); Sawmill processing produces a certain amount of waste, as a result of processing sawlogs into sawn lumber. Waste occurs in the form of fine and coarse waste. Fine and coarse waste are generated on the primary milling machine (band saw) and on the circular saws for transversal and longitudinal lumber cutting. In addition to fine and coarse waste, sawdust also occurs as waste, but due to its specificity, it is not quantified. This paper presents results obtained from several years of research, conducted in five sawmill capacities. The researched capacities were at the territory of the Republic of North Macedonia. The data was gathered under manufacturing conditions. The wood species covered in the paper are beech (Fagus sylvatica L.), pine (Pinus sylvesteris, Pinus nigra), oak (Quercus sessiliflora), aspen (Populus tremula L.) and fir/spruce (Abies alba/Picea excelsa). The results indicate that beech has the highest percentage of total waste, and fir/spruce has the lowest percentage of total waste. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Determination of the heat energy for hydrothermal treatment of ashwood (Fraxinus excelsior) by log soaking(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2023-09); The treatment of logs by soaking is a complex technological and thermal procedure, in which logs and prisms are used as raw material for the production of peeled and sliced veneers. Such treatment of logs is carried out in pools or pits constructed in the ground. By log soaking two significant changes to the wood are achieved, its coloring and the inevitable plastification of the wood fibers. During this procedure, the time required for air drying is significantly reduced. The soaking medium is fresh water or previously used water at an elevated temperature. This soaking treatment is particularly suitable for logs for the production of peeled and sliced veneer, from which resin must be removed. Soaking is also used when treating wood species that are sensitive to steaming. This paper provides an analysis of the thermal energy required for hydrothermal treatment by log soaking of ashwood (Fraxinus excelsior). The logs were intended for the production of peeled veneer. The log treatment was done in a reinforced concrete pool built in the ground. The total amount of heat for log soaking (Q) consists of effective heat (Qpv) and heat loss (Qzv). The procedure was conducted by the strong treatment mode, with a temperature interval in the range of 70 to 90 °C. The treated logs had a minimum mean diameter of 35,0 cm and a minimum length of 1,8 m. Log soaking was used as a method for defrosting of the logs, due to their low initial temperature, which was– 15 °C. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Analysis of heat and steam consumption during artificial convective drying of oak sawn timber of different thickness(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2023-09); ; ; ; In the paper, the consumption of heat and steam of oak sawn timber with a thickness of 25,0 and 50,0 (mm) are analyzed under conditions of classic convective drying. The drying mode is compiled on the basis of data on the temperature of the drying agent (air), the relative humidity of the air and the speed of air movement in accordance with the current value of moisture in the wood. The heat consumption is analyzed in all stages of the drying cycle such as heating the wood, active drying of the wood, equalization of the average moisture in the wood and conditioning, i.e. equalization of the moisture in the cross-section within ± 2.0 (%). The moisture content of sawn timber at the beginning of drying is about 55,0 (%) and at the end of drying is 10,0 (%). The sawn timber are intended for the production of solid wood panels. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Comparison of log taper in different wood species(Department of Wood Technology, Faculty of Forestry and Wood Technology, University of Zagreb, Croatia, 2023-12); ; The rational yield of the sawlogs is one of the key factor for the prosperity of the sawmill capacity. One of the factors that significantly influence the maximum quantitative yield of sawlogs is the diameter taper. The diameter taper is an inevitable sawlogs occurrence and it is determined by the geometry of the logs. The diameter taper is defined as the difference between the diameters of the two ends of the log, alongside its length. Great differences between these two diameters adversely affect the percentage of maximum quantitative yield. This parametar plays a fundamental role in the classification of logs into quality classes. The aim of the paper is to compare the diameter taper in different wood species. Wood species of interest are: beech (Fagus sylvatica L.), pine (Pinus sylvestris, Pinus nigra), oak (Quercus sessiliflora), and fir/spruce (Abies alba/Picea excelsa). Log length is of important influence in the value of log taper. Therefore, the analysis for the different wood species will also present different groups of lengths, in order to determine the different values for the log taper. The selection of wood species is for the purpose of comparison of the taper values in deciduous and coniferous wood species. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Analysis of heat consumption during convective wood drying of beech sawn timber of different thickness(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2025-09); ; In the paper, the heat consumption of beech sawn timber with a thickness of 50,0 and 70,0 (mm) are analyzed under conditions of classic convective drying. The drying mode is compiled on the basis of data on the temperature of the drying agent (air), the relative humidity of the air and the speed of air movement in accordance with the current value of moisture in the wood. The heat consumption is analyzed in all stages of the drying cycle such as heating the wood, active drying of the wood and conditioning, i.e. equalization of the moisture in the cross-section within ± 2.0 (%). The moisture content of sawn timber at the beginning of drying is about 45,0 (%) and at the end of drying is 8,0 (%). - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Influence of beech sawlogs (Fagus sylvatica L.) quality on milled lumber quality(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2021-11); ; This research paper presents results obtained from conducted research under pragmatic conditions. The results correspond to the influence of the sawlogs quality on the milled lumber quality. The logs were from beechwood (Fagus sylvatica L.). The beech sawlogs, as the key point of research, were graded as 1st and 2nd grade logs. The sawlogs were with the consistent length of l = 4,0 m. The diameter of the 1st grade logs was in the range d = 33,0 ÷ 50 cm, and for the 2nd grade logs d = 34,0 ÷ 50,0 cm. The total number of analyzed logs was 40, 20 logs for each grade. The 1st grade sawlogs had the volume of V = 11,7 m3 and the volume for the 2nd grade logs was the same, V = 11,7 m3. The 1st grade sawlogs had a diameter taper in the range S = 0,5 ÷ 1,0 cm/m and the 2nd grade logs’ diameter taper was S = 0,75 ÷ 1,75 cm/m. The mean value of the diameter taper was as followed: for the 1st grade logs, Ssr = 0,78 cm/m and for the 2nd grade logs Ssr = 1,26 cm/m. It must be noted that the milled lumber values given in this research are relative. After milling the 1st grade logs, the following values were obtained: sawn lumber with a share of 62,80%, dimensional lumber with a share of 18,55%, and heartwood with a share of 18,65%; from a total amount of 100%. The 2nd grade logs gave the following values, from the total amount of 100%: 51,80% sawn lumber; 21,38% dimensional lumber, and 26,82% heartwood. The dimensional distribution of the milled lumber, for the 1st grade, from the total amount of 100%, was as following: 44,60% long milled lumber (l > 2,0 m); 20,84% short milled lumber (l = 1,0 ÷ 1,90 m); 15,91% extra short milled lumber (l = 0,5 ÷ 1,0 m) and 18,65% heartwood. The 2nd grade milled lumber had the following dimensional distribution: 38,20% long milled lumber (l > 2,0 m); 14,76% short milled lumber (l = 1,0 ÷ 1,90 m); 20,22% extra short milled lumber (l = 0,5 ÷ 1,0 m) and 26,82% heartwood, from the total amount of 100%. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Analysis of the heat energy used for steaming edged beech lumber (Fagus sylvatica L.) with thickness of 50 mm(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2022-11)Milled lumber steaming is a technological procedure, during which lumber is exposed to the influence of saturated water vapor, temperature and pressure, in a closed system. The purpose of the steaming process is to change the color, improve the properties of the lumber, sterilization, as well as to remove some lumber defects that had occurred during the drying process. This paper presents the results obtained from analysis of the heat energy required for steaming edged beech lumber with thickness of 50 mm. Beech (Fagus Sylvatica L.) is the dominant wood species in primary wood processing industry on the territory of North Macedonia. That being the case, the data related to steaming beech lumber is of particular interest. The heat energy of a metal automated steaming chamber with a capacity of 28 m3/cycle was analyzed. Based on the parameters given, an analysis and technical calculation of the heat energy required for steaming the beech lumber were conducted. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Milled lumber steaming chambers(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2022-11); This paper describers the steaming chambers used for thermal treatment of milled lumber. The steaming process is a principal operation, as part of the primary wood processing. This technological process is a relevant prerequisite for obtaining quality lumber for final manufacturing. Steaming processes take place in constructed facilities called steaming chambers, under normal range of barometric pressure. This paper presents the two methods used for milled lumber steaming, direct vaporization and indirect vaporization. The two methods are characterized by different functional principles and different installation of the steaming chambers. An important aspect for obtaining quality lumber is the level of automatization of the steaming process. Automatization is composed by technical equipment for process monitoring and allows precise insight into the steaming process. The traditional manual steaming chambers monitor the color of the condensate as an indicator of the phase of the steaming process. Alongside automatization, this paper describes the industrial energetic and water supply installation of the steaming chambers. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Technical analysis of a metal chamber for direct steaming of beech lumber (Fagus sylvatica L.)(Faculty of Design and Technologies of Furniture and Interior - Skopje, 2023-12); ; The aim of this paper is the technical analysis of a metal chamber for direct steaming of beech (Fagus sylvatica L.)-edged lumber with a thickness of 50.0 mm. The paper presents the basic parameters of the chamber and calculates the dimensions of the metal chamber and its capacity. The dimensions of the chamber with sawn lumber, the number of chambers, and the volume of the single lumber stack have been analyzed. The steaming of the wood is an important and complex operation during the processing of sawlogs into sawn lumber. Steaming, in addition to being a technological procedure, is also a thermal procedure. The steaming of the sawn lumber is carried out in the presence of water vapor in steaming chambers according to the following two methods: direct steaming of the sawn lumber and indirect steaming of the sawn lumber. In the method of direct steaming of lumber, the steaming medium is saturated water vapor.