RU2037395C1 - Wood drying and impregnating apparatus - Google Patents

Abstract

FIELD: wood-working industry. SUBSTANCE: apparatus has drying and impregnating vacuum chambers and impregnating solution vessel communicated through impregnating solution circulation circuit with centrifugal pump and vacuum circuit with vacuum pump. Vacuum chambers are provided with steam jackets, condensate collection circuit with condensation pots and drying agent forced circulation system having axial fans with guiding shells and outside electric engines. Fan shaft extending through chamber wall is provided with hermetical seal with two rubber reinforced collar and metal ring. EFFECT: increased versatility of drying-and-impregnating unit, provision for combining of vacuum drying and impregnation modes under pressure in a single working volume. 3 cl, 3 dwg

Description

 The invention relates to the woodworking industry and can be used for drying and impregnation of wood.

Wood is dried in the process of removing moisture from it by evaporation. Drying in combination with wood impregnation improves the physicomechanical properties of wood, ensures the stability of the shape and size of wood assortments, increases the resistance of wood to decay and reduces its weight. Liquid and gaseous substances, as well as solid melts, are suitable for wood impregnation. The main industrial method of wood impregnation is autoclave, at a pressure of up to 14 kg / cm ² .

 A device for drying and impregnating wood is known, which is a combined impregnation-drying chamber in which the impregnating and drying space are separated by a movable cover of the impregnating autoclave [1] The device is intended for processing a specific assortment of wooden blanks and has limited use.

A device for drying and impregnating wood, containing an autoclave, in which drying and impregnation of wood is carried out, a maneuvering cylinder and an impregnating oil circulation system comprising a circulation pump [2]
In this case, the process of removing moisture from the wood is carried out using an overheated hydrophobic liquid (oil). However, lumber after such drying cannot satisfy the requirements for wood for furniture and joinery.

The closest in technical essence to this device is a device for drying and impregnating wood containing a vacuum drying and impregnating apparatus connected to a container for impregnating liquid having circulating impregnating liquid systems with a centrifugal pump and vacuum condensation with a vacuum pump [3]
However, this installation cannot be used for mass drying of the material and is designed to obtain a highly specialized type of product, in particular railway sleepers impregnated with creazot.

 To expand technological capabilities, a device for drying and impregnating wood containing a vacuum drying and impregnating apparatus connected to a container for impregnating liquid having circulating systems of impregnating liquid with a centrifugal pump and vacuum condensation with a vacuum pump, according to the invention is equipped with a second vacuum drying and impregnating apparatus, associated with the capacity for the impregnating liquid is similar to the first, having means of internal circulation of the coolant, formed located in l inner wall of the machine casing and guide axial fan with an external motor.

 In addition, the drying and impregnating apparatuses are equipped with a heat exchange jacket, and the axial fan shaft seal assembly is made in the form of reinforced cuffs installed in the housing and directed in opposite directions, between which the stiffening ring of the T-profile is located, and the housing is filled with refractory grease.

 In FIG. 1 shows a diagram of a device for drying and impregnating wood; in FIG. 2 is a cross-sectional view of a chamber, an arrangement diagram of a fan with an external motor, and a fan shaft seal assembly; in FIG. 3 node I in FIG. 2.

 A device for drying and impregnating wood (Fig. 1) contains two drying and impregnating vacuum chambers 1 and 2 and a container 3 for impregnating solution, a system 4 for circulating an impregnating solution with a centrifugal pump 5, pressure 6 and suction 7 pipelines, heating steam supply circuit 8 with heat-exchange jackets 9 of the vacuum chambers 1 and 2, a condensate collection circuit 10 with condensation pots 11, a vacuum circuit 12 with pipelines 13 and 14 for removing liquid and vaporous drying products, a water-cooled vacuum condenser 15, a liquid collector oduktov condensation 16 and liquid ring vacuum pump 17. The vacuum chamber 1 and 2 have the valves 18 and 19 for communicating the internal volume of the chamber with the outside. To load these chambers, a stack of wood 20 is loaded onto a trolley 21, which is mounted on rails 22.

 A guide shroud 24 of an axial fan 25 having a shaft 26 installed in the housing of the bearing assembly 27 with bearings 28, 29 is mounted on the wall 23 of the vacuum chamber from the inside. The housing 30 of the front bearing 29 is equipped with rubber reinforced cuffs 31 and 32 located therein and installed between them ring 33 stiffness. The shaft 26 is fixed in the mounting flange 34 and is connected to an electric motor 35.

 The device operates as follows.

 The material prepared for drying is stacked in stacks 20, and the trolleys 21 are placed in drying and impregnation vacuum chambers 1, 2. After loading the material, the chambers are sealed and heated by supplying steam to the heat exchange shirts 9 and to the working space of the chamber. The axial fans 25 of the internal coolant circulation system are turned on, which feed the drying agent jets onto a stack 20 placed inside the chamber.

 At the end of the heating of the material to a predetermined temperature, the steam supply to the working space of the chamber is stopped, then they are evacuated by means of a vacuum pump 17 and an exposure is performed during which moisture is removed from the processed material. The pressure in the chamber is maintained within 75-200 mm Hg. due to the operation of the vacuum pump.

 The cycle of heating the material and exposure lead to continuous circulation of the heat agent through the stack 20 by means of axial fans 25.

 Once the material reaches the set humidity values, one of the chambers, for example, chamber 1, is put into the impregnation mode, for which the internal circulation system is turned off, the vacuum system is turned off, the centrifugal pump 5 is turned on and the chamber is filled with impregnating solution from the tank 3. Heating steam is supplied to heat-exchange shirts 9 does not stop.

 After filling the chamber with a solution, the centrifugal pump 5 is transferred to the longitudinal circulation mode of the impregnating liquid in the working volume of the chamber. The impregnation cycle, depending on the mode, can be carried out either under vacuum or pressure.

 After the impregnation process is completed, the impregnating solution with the pump 5 is pumped into the container 3 for impregnating the solution. Chamber 1 is transferred to the wood aftertreatment cycle during heating steam supply, the operation of the coolant circulation circuit and the connected vacuum system. After the end of the full cycle of impregnation and drying, the chamber 1 is turned off and cooled. After unloading, the chamber is reloaded with fresh wood.

 Chamber 2 during the operation of chamber 1 operates in a drying cycle, without impregnation. Since the impregnation is a longer process than drying, chamber 2 can go through one and a half to two full drying cycles, and at the end of the work it is transferred to the impregnation cycle, and chamber 1 is included in the drying cycles, etc. This ensures the continuity of the device as a whole. Depending on the need, both chambers can only work in the drying cycle (without impregnation).

 Aggregation of several dryers in a single device allows you to increase the productivity of the device, to ensure the continuity of the drying-impregnation process of wood. The use of vacuum chambers in the device allows wood to be impregnated both under vacuum and at elevated pressure, depending on the requirements of the impregnation technology and the properties of the impregnating liquid.

 The design of the seal of the fan shaft through passage ensures the operation of vacuum chambers both under vacuum and at high pressure.

 In general, the device uses more advanced types of heat treatment of wood. Suitable for use with a variety of types of impregnating compounds and preservatives.

Claims (3)

 1. DEVICE FOR DRYING AND IMPREGNATING WOOD, comprising a first vacuum drying and impregnating apparatus connected to a container for impregnating liquid, having circulating systems of impregnating liquid with a centrifugal pump and vacuum condensation with a vacuum pump, characterized in that it is equipped with a second vacuum drying and impregnating the apparatus associated with the capacity for the impregnating liquid is similar to the first one, having means of internal circulation of the coolant formed along the inner wall of the apparatus scraper casing and axial fan with external electric motor.  2. The device according to p. 1, characterized in that the drying and impregnating apparatus is equipped with a heat exchange jacket.  3. The device according to claim 1, characterized in that the axial fan shaft seal assembly is made in the form of reinforced cuffs installed in the housing and directed in opposite directions, between which the stiffening ring of the T-profile is located, and the housing is filled with refractory grease.

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