KR20100094711A - Method for desiccating raw timbers - Google Patents

Abstract

PURPOSE: A method for drying hardwood is provided to reduce time required for drying hardwood by simultaneously drying the inner side and the outer side of the hardwood. CONSTITUTION: A method for drying hardwood is as follows. Through holes(5-1) are formed in a longitudinal direction of hardwoods(5). The hardwoods are arranged inside a drying device. External air flows into the drying device through an inlet(9), and is injected into a supply chamber(3) using a blower(2). The injected external air penetrates through the through holes of the hardwoods. The external air is discharged to outside by passing through an exhaust port(8) in order to dry the hardwoods.

Description

Method for Desiccating Raw Timbers

The present invention relates to a method for drying solid wood, and more particularly, to a method for drying solid wood by drilling a through-hole in the longitudinal direction to solid wood.

Raw materials contain a large amount of water, and when the moisture content decreases, various defects such as splitting heat and discoloration are likely to occur. Particularly, in the case of logs in the form of logs, it will be used as a main material for construction, so it must be properly dried. However, it is very difficult to discharge moisture and it is very difficult to dry it without defects such as heat splitting and discoloration.

If the wood is not dried properly, it will continue to dry after several years or decades, resulting in heat splitting, discoloration, etc. due to shrinkage, mold, insects, etc., and the strength of the wood will fall and the building will be distorted or damaged.

Since timber shrinks when the moisture content decreases, damage to torsion, splitting, etc., is prevented if it is dried up to the equilibrium moisture content of the place of use. Drying wood increases insulation and eases cutting compared to raw materials, reduces the possibility of discoloration and deterioration during transportation and storage, and reduces transportation costs. In addition, unlike living materials, less organic matter causes less pests.

Wood has a very high water content of 30-200% and is composed of several cells. The homogeneity and anisotropy and the location and amount of moisture contained in it have a great influence on the migration of moisture and the occurrence of defects during drying.

In particular, in the case of solid wood (logs, lumber, etc.), the drying stress is very large due to the difference in shrinkage due to the difference in moisture content between the outer and inner layers of wood. Severe defects cause serious defects as structural members.

In general, in the case of heat drying, more defects occur, so most of them rely on natural drying, and it can be used as a structural material only after several years. If the parallel function is less than the surrounding area, the contraction continues after construction, which adversely affects the building.

Recently, a high frequency drying method has been attempted, but due to the nonuniformity of the wood itself, the torsion and cracking of the wood occur during drying, and thus it has not been put to practical use.

It is an object of the present invention to provide a method for drying a solid wood that can be quickly dried without twisting and cracking of the wood to solve such problems.

In order to achieve the above object, the present invention perforates the through-holes in the longitudinal direction to the wood so that external air passes through the through-holes to dry the wood.

The outside air can be natural air, heated air, or steam instead of air.

In the present invention, by removing the core material with high density in the wood, the difference in the density of the inside and outside is reduced so that the shrinkage stress is greatly reduced, and the drying stress is carried out at the inside and outside at the same time, so that the internal and external drying stress is balanced, such as torsion and cracking. Since the thickness of the wood becomes thinner and drying proceeds at the inside and outside at the same time, the drying time is greatly shortened since the moving distance in the wood until the moisture contained in the wood is evaporated into the atmosphere is greatly shortened. It works.

Hereinafter, the present invention will be described in detail with reference to the drawings.

1 is a diagram illustrating a conventional wood drying method and a wood drying method of the present invention, and FIG. 2 is a perspective view of a perforated dry sample and a dry sample in a natural state. 3 is a cross-sectional view of an embodiment of the present invention, Figure 4 is a cross-sectional view taken along the line AA 'of FIG.

Conventionally, the wood is dried in a natural state as shown in FIG. 1A, but the present invention perforates the core of the wood in the longitudinal direction as shown in FIG. 1B to allow natural air, heating air, or steam to penetrate the through hole. Pass the wood through to dry.

As shown in the figure, when the wood is perforated and dried, the thickness of the wood becomes thin and the drying proceeds at the same time from the inside and the outside. Therefore, when the moisture contained in the wood evaporates into the atmosphere, the moving distance in the wood is greatly increased. As the drying time is shortened, the drying time is greatly shortened, and the difference in density of inner and outer parts is greatly reduced, so that the shrinkage stress is reduced, and the drying is performed at the inside and outside at the same time. This ensures that the internal and external dry stress is balanced so that torsion and cracking do not occur.

As shown in the figure, when drying a hole having a size of 1/2 the diameter of the wood, the moving distance of the water is reduced to about 1/4 compared to the case of drying in the natural state, the drying speed is more than four times faster.

The following table shows the result of drying the perforated dry sample (sample A) and natural dry sample (sample B) shown in FIG. 2 with natural air. As shown in this table, after 4 months of drying, the water content was 92.85% for sample B, compared to 76.97% for sample A. That is, in the case of sample B, 7.15% of water evaporated, whereas in case of sample A, 23.03% of water, which is 3.22 times of sample B, evaporated. Moreover, as time passes, the gap widens, and it turns out that the drying method of this invention has the very big effect.

3 and 4 are specific embodiments of the present invention. In this embodiment, the wood is drilled and placed in a drying apparatus, and the outside air is heated or injected as it is, and the wood is dried by passing through the through hole formed in the wood and the outer circulation space of the wood.

That is, the dry external air is introduced through the inlet 9 of the drying apparatus and heated as it is or by the heater 1 to be injected into the supply chamber 3 through the blower 2, and the air thus injected is supplied to each distribution pipe 4. After passing through the through-hole (5-1) formed in the solid wood (5) through the circular space (6) between the solid wood (5) and the solid wood (5) or between the solid wood (5) and the heat insulating wall (12) The wood is dried by being discharged to the exhaust port (8).

On the other hand, by installing the damper 10 in the inlet (9) it is possible to dry the wood while adjusting the inflow and exhaust of the outside air. Reference numeral 7 is a diaphragm and 11 is an entrance door.

As described above, the present invention is to remove the core material with high density in the wood, the density difference between the inside and outside is reduced, the shrinkage stress is greatly reduced, and the drying stress is balanced inside and outside because the drying proceeds at the same time inside and outside, Since cracks do not occur and the thickness of the wood becomes thin and drying proceeds at the same time inside and outside, the moving time in the wood until the moisture contained in the wood evaporates into the atmosphere is greatly shortened, so the drying time It is greatly shortened.

Although the present invention has been described based on the embodiments, the present invention is not limited thereto, and various changes and modifications can be made within the scope of the technical idea of the present invention. Therefore, the scope of the present invention is not limited by the above description.

In addition, the reference numerals described using parentheses in the detailed description of the present invention and the description of the claims are referred to by reference in order to facilitate understanding of the present invention, and the present invention is not limited to the drawings.

1 is an explanatory diagram of a conventional wood drying method and a wood drying method of the present invention,

2 is a perspective view of a perforated dry sample and a dry sample in a natural state.

3 is a cross section of an embodiment of the invention,

4 is a cross-sectional view taken along the line AA ′ of FIG. 3.

Description of the Related Art

1: heater 2: blower

3: supply room 4: distribution pipe

5: solid wood 6: circular space

7: diaphragm 8: air vent

9: inlet 10: damper

11: door 12: insulation wall

Claims (9)

In the method of drying solid wood, The method of drying wood, characterized in that the through-hole in the longitudinal direction to the wood to allow the outside air to pass through the through-hole to dry. Through-hole 5-1 in the longitudinal direction in the wood 5, Placed in the drying apparatus, By introducing the outside air into the drying device through the inlet (9), Injected into the supply chamber (3) through the blower (2), The outside air injected into the supply chamber (3) passes through the through hole (5-1) of the wood 5 through each distribution pipe (4), The outside air passing through the through hole 5-1 through the circulation space 6 between the log 5 and the log 5 or between the log 5 and the heat insulating wall 12 is exhaust port 8. Wood drying method, characterized in that for drying by being discharged to the outside through. The method of claim 2, Installing a damper (10) in the inlet (9) to dry wood, characterized in that for controlling the inflow and exhaust of the outside air. The method according to any one of claims 1 to 3, Drying method of wood, characterized in that the outside air is heated air. The method according to any one of claims 1 to 3, Drying wood, characterized in that the external air is natural air. The method according to any one of claims 1 to 3, Drying wood, characterized in that to use steam instead of the outside air. In the drying apparatus of solid wood, Insulating wall 12 partitioning from the outside, Door (11) for import and export of timber and worker's access, Inlet of external air (9), A blower (2) installed in the inlet (9), Supply chamber (3) connected to the inlet (9), A plurality of distribution pipes 4 installed in the supply chamber 3 and Drying apparatus for solid wood composed of exhaust ports (8). The method of claim 7, wherein Drying apparatus of wood, characterized in that the heater (1) is installed in the inlet (9). The method of claim 7, wherein Drying apparatus of wood, characterized in that the damper 10 is installed in the inlet (9).

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