I. Translate the following words and phrases from the text:
to file, to fit, mating surfaces, face, a great number of, convex surfaces, triangular file, to prevent, strip
II. Retell the text giving answers to the following questions:
1. What is filing? 2. What operations are performed with a file? 3. What is the difference between a file and a chisel? 4. What files are used for filing depending on the shape of the surfaces to be finished? 5. Why is the shape of flat files not quite flat? 6. What files are used for filing convex and concave surfaces? 7. What are square files and triangular files applied for? 8. What holes are round files used for?
III. Supply antonyms for the following words:
flat, convex, soft, different
IV. Give the derivatives from the following words and translate them into Russian:
to differ, to operate, file, to fit, diagonal, to finish, to separate
V. Change the following sentences using the clauses instead of participle phrases and translate the sentences into Russian:
Example: Files with convex surfaces, preventing all their teeth from cutting at the
same time, are used for filing convex and concave surfaces.
Files with convex surfaces which prevent all their teeth from cutting at
the same time are used for filing convex and concave surfaces.
1. Files are generally made with convex surfaces being thicker in the middle than at the ends. 2. Files having various shapes of cross-section such as square, flat, round, etc. are used in metal-cutting practice. 3. When filing convex surfaces one uses a half-round file. 4. A file is an instrument having teeth on its face. 5. Files are tools belonging to the group of locksmith's cutting instruments.
VI. Make up questions to which the italicized words are the answers:
1. A file has a great number of fine cutting teeth. 2. These teeth are used for removing chips from the workpiece to be treated. 3. Depending on the shape of the surfaces to be filed various kinds of files are used. 4. No, flat files are not used for filing round holes. Round files are used. 5. No, knife files are not used for filing soft metals, but rasps are used. 6. Yes, diamond-shaped files are used for filing metal in narrow places.
VII. Giving answers to the following questions describe Fig. 9:
1. What is a file? 2. What principal parts does a file consist of? 3. In what cases is a square file used? 4. Which file is used for filing angles? 5. What material are diamond-shaped files made of? 6. In what eases are knife files used?
MECHANICAL TOOLS
Both in maintenance and in repair of machines all kinds of fitting operations are applied. An important role is played by disassembling and assembling operations. Special instruments are used for performing these operations.
Among the variety of mechanical tools used for disassembling and assembling machine parts and in their repairing are wrenches (Fig. 10). According to their construction and application wrenches may be of different types: single- ended
and double-ended nut wrenches, adjustable wrenches, socket wrenches and special wrenches.
Fig.
10 Wrenches:
1 — single-ended wrench (a — handle; b — head; с —span); 2 — double-ended wrench; 3 — adjustable wrench; 4 — socket wrench
A nut wrench is used for screwing and unscrewing nuts. It consists of a handle and a head with an opening known as the span.
Adjustable wrenches may be used for unscrewing nuts and bolts of different dimensions.
Socket wrenches are applied in cases when nuts or bolt heads located in recesses are hardly accessible for a nut wrench.
Special wrenches are used for unscrewing and screwing nuts of a definite type.
Wrenches are used by drivers for repairing cars, in locksmith's shops and fitter's shops. Fitters use them to screw different types of machine parts as: washers, bolts, shafts, etc. Plumbers use them to repair pipes, taps, etc. Besides different types of wrenches there are round pliers or needle nose pliers which are widely used by locksmiths, electricians and other specialists for gripping, screwing or cutting off thin metal and wires.
Exercises