Architectural Environmental, And Process Flow in Constructing Modern Factories for Manufacturing Eco-Friendly Furniture

Today, a dominant trend in factory construction is to account for the eco-economic aspects of their further operations. It requires sustainable technological solutions, with regard for structural specificities or for production technology used. At the same time, the buildings shall be architecturally attractive and distinct. In the paper, the author considered architectural, technological, structural, ecological, and economic factors for construction of wood-processing and furniture-making facilities. The author analyzed the actual Project Design to build the type of facility in Krekhiv village, Zhovkva district, Lviv region (western Ukraine) as commissioned by a well-known French company (the author have been engaged in the design). The study focused on a wood-processing Woodman company designed for the midtech production of edge glued panels and furniture. According to the design documentation by types of products planned, the Project Design provided for the following production units: unit for wood-sawing and drying; unit for mechanical processing of wood, production of edge glued panels and furniture; unit for mechanical repairs; and an administrative and services unit. The anticipated annual production capacity is: for edge glued panels – 600 m3 a year, furniture production– up to 4,000 pc a year. “Wood-sawing unit”, according to the Project Design, is organized according to the following principles of production technology based on the stages and operations: stockholding and storage of round timber (sawtimber); cutting the sawtimber into the shaped timber and logs; stocking the sawn timber (untrimmed boards) into stockpiles and on separators for further atmospheric and chamber drying. Sawn timber drying is taking place in the “Drying Unit”. It is the process of moisture removal from timber to a certain degree of humidity. The Project Design provided for the atmospheric drying of logs and boards in the furnished stockpiles under the roof, and artificial seasoning in a steam-curing and drying chambers. The artificial seasoning technology for sawn timber and logs is organized with the help of drying chambers and a boiler room with a sawdust bunker. The “Unit for Mechanical Wood Processing, Production of Edged Glued Panels and Furniture” is used for production of the edged glued panels from the sawn timber coming from hardwood (beech, oak). The production process of the edged glued panels includes the following stages: 1) cross-cutting of dry boards; 2) line cutting of board edges for the rough-sawn stock; 3) primary mechanical processing; 4) sorting by quality, color; 5) end-jointing gluing line; 6) log finishing; 7) press-molding of logs into panels; 8) panel surface preparation; 9) size cutting; 10) preservative treatment; 11) quality control; 12) storage and sales. "Administrative and Service Block", according to the Project Design, is an inbuilt part of the Main Building (Unit). It is a two-story insert separated with the fire safety barriers from the manufacturing facilities. It has isolated outside entrances and a technological corridor linking the manufacturing facilities. With account for production process requirements, fire safety, and sanitary standards, the Unit is divided into several personal services rooms for the staff and administrative rooms.

Laws Governing Free and Actual Drying Shrinkage of 50 mm Thick Mongolian Scotch Pine Timber

The relationships between free shrinkage and actual shrinkage of different layers in Mongolian Scotch pine (Pinus sylvestris var. mongolica Litv.) were explored to provide basic data for the further study of drying shrinkage properties. The free shrinkage coefficients at different temperatures and the actual shrinkage strain of each layer were examined under conventional drying. The results showed high precision of free drying shrinkage of corresponding layers of thin small test strips in each layer of sawn timber. The free shrinkage increased linearly as moisture content declined. At the same temperature, the free shrinkage coefficient reached the largest values for the first layer (above 0.267), while the smallest values were recorded for the ninth layer (below 0.249). Except for the ninth layer, the free shrinkage coefficients in width directions of other representative layers decreased as temperature increased. At constant temperature, the difference in free shrinkage coefficient of test materials in the length direction of sawn timber was small for the first layer, but slightly larger and changed irregularly in the fifth and ninth layer direction. At the end of conventional drying, the plastic deformation of each layer in the early stage of drying showed a reducing trend or even reversal due to the effects of reverse stress and later damp heat. In sum, these findings look promising for future optimization of wood drying process.

Efficiency of Visual and Machine Strength Grading of Sawn Timber with Respect to Log Type

A batch of pine timber sawn from butt, middle and top logs was strength graded with the visual method (classification into grading classes KW—best quality, KS—medium quality, KG—inferior quality and Reject) and with the machine strength grading method—performed with the use of a mobile timber grader (classification into C strength classes). We compared the efficiency of grading classes and strength classes, depending on the type of log from which the material was obtained (butt, middle, top). Next, a strength grading machine was used to measure the modulus of elasticity in bending (MOE) and static bending strength (MOR). The ANOVA confirmed the influence of both the log type (butt, middle, top), the C strength class, and the visual strength grading class on the values of density (DEN) and MOR. Timber density and MOR decreased from the butt log section to the top log section. The ANOVA confirmed the influence of log type on MOE values, but only to a limited extent.

QUALITY MANAGEMENT OF LUMBER DRYING IN CONVECTIVE AUTOMATIC CHAMBERS

The timber industry complex of Russia has no less potential than the recognized flagships of the Russian industry – the oil and gas sector, the metallurgical and military-industrial complex. The potentialities of the Russian woodworking industry and such a traditional industry as sawmilling are especially great. According to available forecasts, despite significant growth in the production of panel materials, cardboard and paper, the demand for sawnwood will increase, especially in Europe. The recommendations for improving sawmill production emphasize the need to increase the volume of sawn timber drying, expand the range of products by producing targeted dry sawn timber, and bring the requirements for the quality of sawn timber drying to consumer requirements. Specific issues related to quality management of woodworking products have basically been resolved. At the same time, there are a number of bottlenecks in the management of drying quality that cannot be solved at once. This is especially true for issues related to the significant instability of the properties of wood subjected to drying. The system of controlled moisture exchange proposed by the authors makes it possible to largely neutralize the influence of the scatter of the initial properties of wood on the entire drying process. This applies to both the moisture removal process itself and the development of internal stresses in the wood with the provision of the required margin in order to avoid wood cracking. Moreover, the controlled moisture exchange system allows the formation of a drying regime in accordance with the required quality category with minimal energy consumption for drying.

Convective hot-air chambers impulse drying of pear wood lumbers

A review of literary sources on the physical and mechanical properties of pearwood and its use as structural elements of furniture is given. The aerodynamic chambers, their advantages and disadvantages, as well as their modernization are considered. The use of impulse modes for drying hardwood is substantiated, including sawn timber from pear wood 50 mm thick, pilot drying of which began in the modernized URAL-72 chamber in 1999 at Intar LLC, Moscow. The moisture content of the wood samples and the value of internal stresses were controlled in accordance with GOST 16588. The process of impulse drying included from 9 to 12 steps, the temperature at the operating stage ranged from 45 °C to 72 °C. It has been proved that the use of pulse modes for drying pear timber saves up to 30% of electricity.

Effects of Strongbacks and Strappings on Vibrations of Timber Truss Joist Floors

It is well known that the vertical vibrations of lightweight timber floors would cause discomfort to the occupants. As a new kind of flooring system, the metal-plate-connected timber truss joist floors were developed due to their larger spans and easier crossing of pipes and cables after sawn timber and I-joist floors. In this paper, the vibration modes and transfer functions of sixteen metal-plate-connected timber truss joist floors over a nominal span of 6 m were determined experimentally to measure the changes in vibration frequencies and transmissions obtained after the installation of strongbacks and strappings. The results showed that the fundamental natural frequencies of the metal-plate-connected timber truss joist floors at a 400 mm joist spacing were about 15 Hz, while the frequencies of the floors at a 600 mm joist spacing were about 12.5 Hz. The bracing elements of the strongbacks and strappings mainly enhanced the system stiffness in the across-joist direction of the flooring system, but they did not govern the fundamental natural frequencies of the floors and just changed the spacing of adjacent natural frequencies. The bracing elements as secondary elements of the floors also altered the vibration transmission paths in the across-joist direction. The frequencies where the stronger vibration transfers happened in the direction perpendicular to floor joists were generally above 15 Hz. Proper installation measurements of bracing elements in practical control need to be taken to alleviate the vibration response intensity at the targeted locations and frequencies.