RU2089386C1 - Production line for treatment of wood boards during their transportation after hot pressing - Google Patents

Abstract

FIELD: wood-working industry, particular, equipment for manufacture of wood boards or similar laminated materials. SUBSTANCE: the offered production line has means for wood board transportation and substance for their surface treatment, additional closed chamber for heat treatment located directly before or after means of surface treatment. Chamber accommodates means for vertical motion of horizontally located wood boards through circulating, heating, cooling or wetting air flows. This means is made in form of two or more vertically positioned pairs of chain transmissions with cantilevered holders of wood boards secured to them. In addition, the production line has additional chamber for conditioning and/or wetting of wood boards and additional means for heat treatment. Additional chamber design is similar to above indicated chambers. EFFECT: higher efficiency of functioning of the offered production line. 3 cl, 14 dwg

Description

 The invention relates to the woodworking industry, and more particularly to equipment for the manufacture of wood-fiber, wood-shaving or other, made from plant or wood materials, wood boards or similar plate materials.

 There are various lines for the production of wood-based panels [1] including equipment for producing wood pulp, preparation of the mass for pressing, carpet forming, hot pressing and subsequent processing of the plates by impregnation, heat treatment and conditioning. A prerequisite in industrially widespread technologies for producing high-quality wood boards is heat treatment and conditioning.

 Heat treatment and conditioning operations are designed to increase the physicomechanical properties of plate materials, increase their water resistance and increase strength characteristics.

Heat treatment chambers are divided into periodic and continuous chambers according to the nature of the process. Currently, the most widespread are periodic chambers, consisting of load-bearing steel walls with internal insulation, doors with explosion-proof valves, ventilation ducts, axial fan, fire extinguishing equipment, cold water injection devices and instrumentation [1, p. 105] During the heat treatment, the plates are rolled on special trolleys into a chilled (up to 80 ^o C) chamber and by means of an air fan with an air heater, the temperature is raised to the working level (165 ^o C) and heat treatment is carried out at an air speed of 5 m / s for 3 6 hours Then the chambers are again cooled (up to 80 ^o C for 1.5 2 hours) and trolleys with plates are rolled out. After this, the plates are subjected to conditioning (humidification to the required humidity) to ensure their optimum humidity by treating them directly on trolleys with humidified air in chambers of a similar design.

 The disadvantages of these chambers for heat treatment and conditioning are their increased metal consumption, relatively low productivity, high complexity of loading and unloading plates and high losses of thermal energy.

 Continuous heat treatment chambers are known, for example, the Swedish company "FLEKT" chambers, called "rotiform", which are a rotating (up to 12 m in diameter) rotor, in the peripheral part of which are fixed in the radial direction of the plate (with a maximum size of 2.4 x 7.2 m in the amount of about 1000 pieces), and in the central part of which a fan is installed. The performance of the camera with a plate thickness of 3 mm to 500 pieces of plates per hour [1, p. 108] however, these cameras due to their bulkiness and complexity of operation are not widely used.

 The disadvantages of data and other similar chambers for heat treatment are the difficulty of regulating the optimal heat treatment modes (optimal temperature, humidity and speed of air flow), the difficulty of loading and unloading plates, cumbersome and, as a result, high losses of thermal energy.

 A known line for transporting plates after pressing [2] includes an unloading conveyor, roller conveyor, nets, upper and lower roller conveyors and a special device for wedging the plate and mesh and feeding the plate to the upper conveyor, and nets to the lower conveyor. This line allows you to continuously separate the plates from the nets and transport them to the subsequent processing stages, however, it requires the manufacture of wood-fiber boards of high quality installation of an additional impregnating machine and special loading and unloading devices, and special chambers for heat treatment and conditioning, separately located and working as a rule, in the mode of periodic action.

The closest in technical essence and the result obtained from use (prototype) is a line for processing wood-based panels during transportation after hot pressing, containing means for transporting the boards, means for their surface treatment directly during transportation and a chamber for heat and / or moisture treatment of the boards [3]
This line can significantly increase the productivity of the plate manufacturing process, however, it requires special additional equipment for heat treatment and conditioning of the plates.

 Thus, the production lines of wood-based panels, known from the modern level of development of science and technology, and the line for transporting plates after pressing for impregnation and further processing are very complex and labor-consuming to manufacture and operate, have insufficient productivity, increased energy losses and limited possibilities for the production of increased panels quality. Since in practice it is possible, due to limited productivity and increased energy and labor costs of equipment used in impregnation, heat treatment and conditioning, to produce only up to 10 percent of high-quality plates from the total volume of plates obtained after hot pressing. Therefore, the structural imperfection of the equipment used in practice not only limits the ability to meet the urgent social need for high-quality wood boards, but also causes unacceptably high energy losses and increased laboriousness of plate production.

 The aim of the invention (the required technical result) is to increase the efficiency of the line for processing wood boards during transportation after pressing by increasing productivity and improving the quality of the boards by providing the possibility of heat treatment and conditioning of the boards directly during their transportation, reducing the material consumption of the equipment and its complexity maintenance, reducing energy loss, providing the ability to fully automate all technological operations and automatic maintenance of optimal technological regimes for the production of wood-based panels.

 The goal (the desired technical result) is achieved by the fact that the line for processing wood boards during transportation after hot pressing, containing means for transporting the boards, means for surface treatment directly during transportation and a chamber for heat and / or moisture treatment of the boards, according to the invention is provided with at least one additional chamber for heat and / or moisture treatment of the plates installed before and / or after the means for surface treatment of the plates.

 Moreover, the heat treatment chamber contains inside the means for vertical movement through horizontal, heating, cooling or moisturizing air flows of horizontally arranged plates, made, for example, in the form of two or more vertically arranged pairs of chain transmissions with cantilever plate holders fixed to them.

 In addition, the line contains an additional chamber for conditioning or humidifying the stoves.

 In addition, the conditioning chamber is similar in construction to the cooking chamber for cooking plates.

 In addition, the line contains additional means for processing plates, for example for laminating them, or for additional surface treatment, for example, embossing of a relief on a surface or painting.

 As follows from the examples of practical implementation of the invention below, the proposed line for processing wood boards during transportation after pressing allows to increase the productivity and quality of the boards by providing the possibility of heat treatment and conditioning of the boards directly during transportation, to reduce the material consumption of the equipment and the complexity of its maintenance, reduce energy losses, provide the ability to fully automate all technological operations th and automatic maintenance of optimal technological regimes for the production of wood-based panels.

 Thus, it can be argued that the goal of inventions is achieved and that the combination of essential features of the invention allows to obtain a new technical result, which until now has not been achieved practically.

 Figure 1 9 shows the general design of the line for processing wood-based panels after extrusion, with the main nodes of the line indicated by the following symbols: PR hot-pressing press, O surface treatment unit, THEN heat treatment chamber, K conditioning and / or humidification chamber; in FIG. 10 is a sectional view of a heat treatment chamber or a conditioning chamber (their designs are similar to each other); 11, 12 and 13, 14 show possible variants of the design of the chambers for heat treatment and / or conditioning and show the main stages of their functioning.

 In FIG. 2, 3 design features of the line for transporting plates after pressing with their simultaneous surface treatment.

 The line for processing wood boards after extrusion includes located in various combinations, connected in series to a single transport line (Fig. 1 9), a hot extrusion press 1, means for surface or other processing 2, a heat treatment chamber 3 and a conditioning chamber and / or moisturizing 4.

 Chambers for heat treatment 3 and chambers for conditioning 4 have a similar design (Fig. 10) and contain a closed housing with holes for supplying 6 and removing 7 plates from the chamber. On the sides of the chambers there are openings for supplying 8 and discharging 9 circulating flows of heated, cooled or humidified air, which are moved by means of fans 10 and air ducts 11 in which means for air conditioning are installed 12. Two or more pairs of chain transmissions are installed inside the camera body 5 13, on which the cantilever holders 14 of the plates are fixed, made with the possibility of vertical movement through the circulation air flows horizontally located on the holders of the plates 15.

 The transportation line of fiberboards after hot pressing operates as follows.

 Wood chips or other wood raw materials are crushed into wood fiber by known methods. Then the wood fiber is prepared for molding, the carpet is formed, it is cold pressed and the carpet is fed to the hot press 1, where hot pressing is performed. Then, immediately after hot pressing (without intermediate cooling), the plate material is subjected to a surface treatment in the tool 2 located directly on the conveyor line, for example, with preparations prepared on the basis of tall products, and without intermediate cooling it is fed to the heat treatment chambers 3, where the plates 15 are subjected to heat treatment at a given temperature and for a given time by their vertical movement in the flows of circulating air. In this case, the heat treatment chambers 3 and the conditioning chambers 4 operate in two stages, at the first of which (Figs. 11, 13), the plates 15 are simultaneously loaded and unloaded (while the chain drives and, accordingly, the plates located on them are stationary relative to the housing), and the second stage (Fig. 12, 13) the chain gears 13 are moved in the vertical direction. At the same time, heated, cooled or humidified air constantly circulates during the entire time the plates are in the chambers in the gaps between the plates.

 If necessary, for example, in the case of obtaining special fire-resistant or bio-resistant plates, they are subjected to additional processing and / or heat treatment, cooled and sent for further processing, for example, for lamination with decorative materials and format cutting.

 Tests in production conditions of the processing line for wood boards directly during their transportation after pressing showed the possibility of its industrial implementation, high efficiency of use, the ability to obtain boards of a given quality and a sharp reduction in environmental pollution. At the same time, experimental studies of the plates obtained using the proposed technology have shown that carrying out all stages of processing the plates after pressing without cyclic cooling and heating (which is typical for traditional equipment) can dramatically improve the quality of the resulting plates, namely, to increase their mechanical strength and water resistance, and significantly increase the productivity of the plate production process, since the use of the invention provides the ability to carry out all stages of processing with a single transport the speed of movement of the plates.

 The use of the processing line for wood boards during transportation after pressing allows to completely eliminate the sizing unit by providing increased strength and water resistance of the boards and thereby significantly reduce environmental pollution, since the bulk of the sizing agents falls into recycled and waste water. At the same time, the use of special processing fluids (for example, tall oil) in the surface treatment of plates on the line of the proposed design allows, with the complete exclusion of traditional highly toxic binders (for example, phenol-formaldehyde or urea resins), to significantly increase the strength of the plates produced on the line and increase their water resistance. At the same time, the need to use traditional energy-intensive and labor-intensive heat treatment and conditioning chambers in maintenance is completely eliminated, which can drastically reduce the consumption and loss of thermal energy, as well as utilize the heat of the spent heat carrier.

 To confirm the reality of achieving the objective of the invention (the required technical result), tests were carried out in a production environment. The studies were carried out on wood-fiber boards manufactured on the production lines of the fiberboard workshop of the Maksatikhinsky DOK (50% aspen, 50% of birch) and the fiberboard workshop of the Podosinovsky timber processing complex (100% aspen). In the manufacture of plates according to the invention, no sizing additives were introduced into the wood-fiber mass, and in the production of plates according to known methods, before forming a carpet, a sizing composition consisting of phenol-formaldehyde resin and paraffin was introduced into the mass in the usual way, and as a precipitant, the sizing composition used a solution of sulfuric acid.

Example 1 (prototype). As a sizing composition, a mixture of phenol-formaldehyde resin (1 to 3% by weight of a.w. fiberboard), paraffin (1%) and sulfuric acid precipitator was used. The consumption of the impregnating mixture 10 12% by weight of A. with. Fiberboard. The processing of the plates was carried out in the usual manner for traditional equipment. The tensile strength under static bending of the resulting plates was 49 57 MPa, swelling for 24 hours in water 10 12%, the density of the plates 980 1100 kg / m ³ .

Example 2 (invention). Traditional binders were not used. The consumption of the impregnating mixture (tall oil) 4.5 5.5% by weight and.with. Fiberboard. The heat treatment and conditioning time is halved. The tensile strength under static bending of the resulting plates was 58 63 MPa, swelling after 24 hours in water 7 9%, the density of the plates 990 1100 kg / m ³ .

 Analysis of the results of production tests showed that the use of the invention allows, with the complete exclusion of the sizing unit and the exclusion of traditional toxic binders, to significantly improve the quality of the plates, in particular to increase the strength and water resistance.

 In addition to this test, it was confirmed that when using the invention, it is possible to increase (up to 100%) the proportion of high-quality boards by removing performance restrictions at the stages of surface treatment, heat treatment and conditioning.

 The plate processing line during transportation after pressing can be used in the wet and dry method of manufacturing wood boards, as well as in the manufacture of other similar plate materials.

 Sources of information.

 1. Rebrin S. P. Mersov E. D. Evdokimov V.G. Fiberboard technology. 2nd ed. M. Forest industry, 1982, 272 p.

 2. Copyright certificate of the USSR N 1395495, cl. B 27 N 3/16, 1986.

 3. Drozdov I.Ya. and Kunin V.M. Production of wood-fiber boards. M. Higher School, 1975, p. 23 25 (prototype).

Claims (3)

 1. A line for processing wood boards during transportation after hot pressing, containing means for transporting the boards, means for surface treatment directly during transportation and a chamber for heat and / or moisture treatment of the boards, characterized in that it is provided with at least one an additional chamber for heat and / or moisture treatment of the plates installed before and / or after the means for surface treatment of the plates.  2. The line according to claim 1, characterized in that the chamber for thermal / / or moisture treatment is equipped with means for the vertical movement of horizontally located plates.  3. The line according to claim 1, characterized in that the means for surface treatment of plates directly in the process of transportation is made in the form of means of lamination, or embossing of the relief, or painting.

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