Measures to Avoid Deterioration of Lumber

Freshly cut wood often contains a lot of excess water and therefore is very heavy. It is necessary that this water should be removed. At the same time a lumber manufacturer should take some measures to reduce warp and to avoid other defects.

Logs should be taken from the forest and sawed into lumber as soon as possible, particularly during warm weather lest they should be attacked by fungi and insects.

At larger sawmills where a considerable supply of logs is often kept it is impossible to saw them into lumber at once. In such cases it is desirable to keep the logs in ponds so that splitting, staining and decay shouldn't occur.

Freshly sawed lumber may split too if exposed to direct sunshine. Dipping it in a solution of toxic chemicals can protect it against attack by fungi and insects. Care should also be taken of the lumber placed in the yard for storage. There are special rules of drying lumber in piles. If these rules are followed, the attack of fungi and insects will be less probable.

Another of the most common defects is splitting. This defect leads to the loss of valuable lumber of 6 to 20 per cent. Different coatings may be divided into two classes. Cold coatings are liquid at ordinary temperatures and can be applied without being heated. Hot coatings are solid at ordinary temperatures and must be applied hot.

Cold coatings can be applied to logs and lumber. They are applied by brush or can be sprayed with a special device. Hot coatings such as pitch and paraffin are well suited for small stocks of lumber. They are low in cost and have high water resistance. Hot coatings are generally applied by dipping the lumber into the pitch or paraffin.

General understanding

Read the text attentively and answer the following questions:

1. What problem does this text deal with?

2. Are there any measures to avoid deterioration of lumber?

3. Is the freshly cut wood heavy or light?

4. Why is it necessary to remove the excess water?

5. Where is it better to store the logs before sawing: in the piles or in the pond?

6. What can protect the freshly sawed lumber against the attack by fungi and insects?

7. What is another of the most common defect?

8. What can protect lumber from splitting?

9. How are the cold coatings applied to lumber?

10. How is lumber treated with hot coatings?

Vocabulary

Exercise 1. Match the English words in A with their Russian equivalents in B.

A. B.

1. contain 1. расщепляться

2.heavy 2. коробиться

3. remove 3. содержать

4. reduce 4. бассейн

5. warp 5. удалять

6. saw 6. хранить

7. supply 7. уменьшать

8. store 8. запас

9. pond 9. пилить

10. split 10. тяжелый

Exercise 2. Find the English equivalents to the following Russian.

принять меры; значительный; опрыскивание; обесцвечивание; погружение; раствор; осторожность; биржа; штабель; потеря; покрытие; наносить; твердый; запас; смола (вар).

Exercise 3. Choose the words from the text which have the similar meaning.

degradation; freshly felled; producer; drawback; decrease; deformation; increase; lumber mill; stock; crack; immediately; seasoning; coverage; cheap; sawn timber.

Exercise 4. Fill in the blanks with the words from the box.

1. Forests ______ surface waters against pollution with harmful substances. 2.

The natural resistance of timber is not a fixed ______. 3. High temperatures affect timber properties if timber is ______ to them for a long enough time. 4. The influence of aggressive gases have no negative effects on either ______ timber or glued timber. 5. Paint______ provide good protection against rainfall. 6. Timber ______ to UV-radiation suffers from ______. 7. ______ and ______ are the two main biological agents responsible for timber ______ in service. 8. Different ______ are normally ______ to timber before use. 9. Once trees are felled they are prone to biological ______.

Grammar

Exercise 1. Find 3 sentences with the subjunctive mood in the text and translate them into Russian.

Exercise 2. Use the verb in brackets in the subjunctive form.

1. He suggested that some birches (to plant) in our park. 2. I wish I (to be) a woodworking engineer. 3. It is necessary that timber resources (to utilize) rationally. 4. If our sawn goods didn't have such high quality, they (not to be) in such a great demand abroad. 5. It (to be) impossible to imagine our economy without forest products. 6. Were the growing conditions unfavourable, the annual rings (not be) wide. 7. It is important that the variety of tree species in our locality (to increase). 8. The professor wished that the students (to study) the influence of weather conditions on the growth of pine. 9. It is necessary that the damage from forest fires in our region (to minimize).

Exercise 3. Put the verbs in brackets into the correct tense.

1. A: I wish Paul would tell (tell) me what is wrong with him.

B: Yes, he seems very upset, doesn't he?

2. A: I wish I (not shout) at the children like that.

B: Why? They were being very naughty.

3. A: I wish you (tidy) your room more often.

B: Sorry, I'll try to.

4. A: I wish I (study) harder before the exams.

B: I thought you did.

5. A: I wish I (be) back at school again.

B: Those were great days, weren't they?

6. A: I wish I (buy) those shoes we saw today.

B: Why not go back and buy them tomorrow?

7. A: I wish you (try) harder with your Maths homework.

B: Sorry. I find it very difficult.

8. A: I wish we (go) to England last summer.

B: We could do this year if you like.

Exercise 4. Fill in the gaps with an appropriate auxiliary verb.

1. I don't know many people, but I wish I did.

2. He can't drive, but he wishes he ____.

3. I'm not very wealthy, but I wish I ____.

4. She probably won't help me; but I wish she____.

5. He hasn't got any pets, but he wishes he ____.

Exercise 5. Translate into English.

1. Без леса наша жизнь была бы невозможной. 2. Мы хотим, чтобы наше деревообрабатывающее оборудование было усовершенствовано. 3. Желательно, чтобы древесину обработали антисептиками. 4. Древесину надо хорошо высушить иначе она начнет гнить (чтобы она не загнила). 5. Уничтожение многих пород деревьев привело бы к изменению климата. 6. Ситуация требует, чтобы были приняты должные меры по сохранению некоторых пород деревьев. 7. Жаль, что многие наши леса уничтожаются пожарами. 8. Без клеев фанера, древесно-стружечные плиты и многие другие древесные продукты были бы невозможны. 9. Важно, чтобы циркуляция воздуха была одинаковой по всему штабелю. 10. Необходимо, чтобы вода из древесины была удалена.

Speaking

Speak about:

1. The necessity of taking logs from the forest as soon as possible.

2. The ways of lumber protection against the agents of deterioration.

Unit 9

Grammar:

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