RU2375655C1 - Method of preparing timber for long-term storage - Google Patents

Abstract

FIELD: heating, drying.

SUBSTANCE: method involves preliminary treatment of timber by redistributing moisture in it at creating hydraulic blocks in its ends. The treatment is carried out in a centrifuge. The centrifuge rotation axis is passed through the middle of the timber package; moisture content in the ends of the preliminary treated timber amounts to more than 70% and that in the centre - less than 60%.

EFFECT: method allows for the preparation of timber for long-term storage, high output and quality of lumber after timber long-term storage, reduction of labour input, exclusion of expensive chemical agents use and improvement of labour conditions.

6 dwg, 1 ex

Description

The invention relates to the forest industry and can be used in the preparation of timber for long-term storage.

It is known that freshly cut wood during storage at a moisture content of 60-80% is affected by fungi. But for mushrooms, humidity above 80% and below 60% is almost unacceptable. But at low humidity, cracks appear in the timber (especially at the ends), which leads to a low yield of lumber from them and an output of low grade lumber.

A known method of protecting timber, for example, from rotting by impregnating them with chemicals (antiseptics). [A.S. USSR No. 140135, publ. 1961].

The disadvantages of this method are the low yield of lumber, their low quality after prolonged storage of timber, increased harmfulness to humans due to the high toxicity of the substances used for impregnation, the high complexity of the protection process, and the economic inexpediency of the need to use preparations for impregnation.

A known method of protecting felled wood and timber from rotting, cracking and fungal infection by the use of moisture-proof coatings, for example based on latex [A.S. USSR No. 122277, publ. 1959 - prototype].

The disadvantages of this method are the increased harmfulness to humans due to the high toxicity of the substances used for impregnation, the high complexity of the protection process, economic inexpediency due to the need to use chemicals, low efficiency of the method.

The technical task of the invention is to increase the efficiency of the method of preparing timber for long-term storage, ensuring high yield and quality of lumber after a long storage of timber, reducing the complexity of the process, increasing its economic feasibility without the use of expensive chemicals and improving working conditions.

The problem is achieved in that in the method of preparing timber for long-term storage, including preliminary processing of timber, preliminary processing is carried out by the redistribution of moisture in the timber when creating hydraulic plugs at its ends, which is performed in a centrifuge, and the axis of rotation of the centrifuge passes through the middle of the package of timber, while humidity at the ends of pre-treated timber is more than 70%, and in the middle - less than 60%.

The invention has the following differences from the prototype:

- pre-treatment is carried out by the redistribution of moisture in the timber when creating hydraulic plugs at its ends;

- pre-processing is carried out in a centrifuge, and the axis of rotation of the centrifuge passes through the middle of the package of timber;

- humidity at the ends of pre-treated timber is more than 70%, and in the middle - less than 60%.

This will increase the efficiency of the method of preparing timber for long-term storage, increase the yield and quality of lumber, reduce the complexity of the process, increase its economic feasibility without the use of expensive chemicals and improve working conditions.

In the patent information fund that we reviewed, no technical solutions with the indicated differences were found, as well as technical solutions with the specified set of distinctive features.

The invention is applicable and will be used in the industry in 2008.

Figure 1 shows a diagram of a centrifuge with timber placed on it (or a package of timber);

figure 2 is the same, a top view.

Figure 3 shows the timber after pre-processing.

Figures 4 and 5 show graphs of the state of humidity in various zones of timber not prepared and prepared according to the claimed method after 1.5 years of storage in atmospheric conditions (two lots of timber are considered).

Figure 6 presents the degree of damage to timber not prepared for storage and prepared for storage by the claimed method, as well as assorted yield of wood in both cases after 1.5 years of storage under atmospheric conditions.

The centrifuge contains a platform 1 with an axis of rotation 2. Timber (or a package of timber) 3 is laid on platform 1.

The method is as follows.

EXAMPLE.

Timber (or a package of timber) 3 is laid on the platform 1 so that the axis of rotation 2 passes through the middle of the package of timber and the preliminary processing of timber 3 begins by centrifugation, while the moisture in the timber 3 is redistributed from the middle to the ends, forming hydraulic plugs at the ends. The moisture content at the ends of the timber is more than 70%, and in the middle - less than 60% (see figure 3, graphs 2 and 3). Such timber can be stored for a long time.

The moisture content of the ends of more than 70% does not cause cracking, and the humidity inside less than 60% and in the ends of more than 70% do not like mushrooms.

The most effective centrifugation conditions (see FIGS. 4 and 5) are as follows:

centrifugation with the mode F ₀ = 193-220 m / s for 400-420 s,

where F ₀ is an indicator of the regime. (is the product of the angular velocity of rotation 1 / s and the radius of the centrifuge, m, which is equal to half the length of the timber);

t is the centrifugation time, s;

Chart 1 - characterize unprepared timber;

Charts 2 and 3 - characterize centrifuged timber.

The degree of damage and assortment yield of wood after prolonged storage in atmospheric conditions for 1.5 years is as follows.

In the first surveyed batch of timber, Figure 4:

- untreated pre-timber was end-to-end defeated by steaming, and marble rot passed to a depth of 25 cm.

The output of lumber was as follows: p / m IV s - 40%, Dr - 60%.

- in pre-treated timber, the defeat by steaming (in the form of strips) went to a maximum depth of 56 cm from the end, while the width of the strips was from 2 to 15 cm. There was no marble rot in this consignment of timber.

The output of lumber was as follows: s / m I s - 48%, II s - 36%, Dr - 18%.

The processing mode was F ₀ 193-199 m / s; t = 420 s.

In the second surveyed party of timber, Figure 5:

- untreated pre-timber was end-to-end defeated by steaming, and marble rot hit the prickly part, while passing to a depth of 50-120 cm.

The output of lumber was as follows: p / m IV s - 60%, Dr - 40%.

- in pre-treated timber, the damage to the frontal part by sub-steaming (in the form of strips) was 7%. There was no marble rot in this consignment of timber.

The output of lumber was as follows: s / m I s - 93%, Dr - 7%.

The processing mode was F ₀ 220 m / s; t = 420 s.

Thus, the claimed technical solution will improve the efficiency of the method of preparing timber for long-term storage, provide a high yield and quality of lumber after a long storage of timber, reduce the complexity of the process, increase its economic feasibility without the use of expensive chemicals and improve working conditions.

Claims (1)

A method of preparing timber for long-term storage, including preliminary processing of timber, characterized in that the preliminary processing is carried out by the redistribution of moisture in the timber when creating hydraulic plugs at its ends, which is carried out in a centrifuge, and the axis of rotation of the centrifuge passes through the middle of the package of timber, with moisture at the ends pre-processed timber is more than 70%, and in the middle - less than 60%.

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