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Transform the following sentences a) into Second Conditional, b) into Third Conditional. The first one has been done for you.
1. If the first step in metal casting involves the creation of a mold, the molten metal will be poured and cooled.
a) If the first step in metal casting involved the creation of a mold, the molten metal would be poured and cooled.
b) If the first step in metal casting had involved the creation of a mold, the molten metal would have been poured and cooled.
2. If sand is the most common molding material, it will be used in foundry processes.
3. If green sand molds are used in 85% of foundries, these molds will be the most important for us.
4. If the sand provides the structure for the mold, it will be used in foundry processes.
5. The carbonaceous materials will be used in foundry processes, if they prevent rust.
6. If the water is used to activate the clay it will be useful for this research.
7. If sand molds are used only once, they won’t be rather useful.
8. If most of the sand from green sand molds is reused, future molds will be made from this sand.
9. If cores are strong and hard to withstand the molten metal, they will be removed after the metal piece cooled.
10. If shell molds use chemically bonded sand, they will be used in our industry.
8. Answer the following questions:
1. What is done to remove the mold?
2. How is solid waste created?
3. How is the metal piece cleaned?
4. What can be remained on the metal piece?
5. Where can surface coating be applied?
6. What does the first step of metal casting involve?
7. What is the most common molding material?
8. What are the components of green sand?
9. What bind the sand together in the mold?
10. What types of molds do you know?
1. Read and translate the following text:
Electric Arc Furnaces. Electric arc furnaces are often used in large steel foundries and steel mills. The metal is charged into the furnace, with additives to make recovery of slag easier, and heat to melt the metal is produced with an electric arc from three carbon or granite electrodes.
The electric arc furnace is lined with refractories which slowly decompose and are removed with slag. Electric arc furnaces also usually employ air emissions equipment to capture most air pollution.
Induction Furnaces. Induction furnaces are the most widely used type of furnace for melting iron and are increasingly popular for melting non-ferrous metals. They are popular because they provide excellent metallurgical control and are relatively pollution free. Coreless induction furnaces are used for smaller (5-10 ton) operations. In coreless induction furnaces, refractory lined crucibles are surrounded by water-cooled, copper coils.
For larger quantities, channel induction furnaces are used. In these furnaces the copper coils are surrounded by inductors to promote metal melting. Channel furnaces are commonly used to hold the molten metal prior to casting.
Induction furnaces use alternating currents to create heat and melt the metal. The refractories are usually made of silica, alumina or magnesia. They break down over time and become part of the slag.
2. Find in the text English equivalents to the following words and word combinations:
дугова піч, сталеливарний завод, виділення шлаків, повітряні викиди, індукційна піч, тигельна індукційна піч, тигель, мідна спіраль, руйнування, шлак.
3. Make up sentences from the following words. Translate them into Ukrainian.
1. Arc, large, steel, mills, steel, foundries, and, electric, furnaces, are, often, used, in.
2. Furnaces, coreless, induction, smaller, operations, are, use, for.
3. Quantities, for, larger, furnaces, are used, induction, channel.
4. Fill in the gaps with the following verbs in appropriate tense form according to the meaning:
to make, to surround, to use, to employ, to remove, to line, to use, to charge
1. Electric arc furnaces _____ in large steel foundries and steel mills.
2. The metal _____ into the furnace.
3. The electric arc furnace _____ with refractory which slowly decompose and _____ with slag.
4. Coreless induction furnaces _____ for smaller operations.
5. Refractory lined crucibles _____ by water cooled, copper coils.
6. Electric arc furnaces usually _____ air emissions equipment to capture most air pollution.
7. The refractory _____ of silica, alumina or magnesia.
5. Answer the following questions:
1. Where are electric arc furnaces used?
2. What do electric arc furnaces usually employ?
3. What is the most widely used type of furnaces?
4. Why are induction furnaces popular?
5. When are channel furnaces used?