Read the text again to decide if the following statements are true or false. Correct the false ones with the facts from the text.
Date: 2015-10-07; view: 649.
LANGUAGE PRACTICE
1. Match the following words and their meanings by placing proper numbers on each blank:
| 1) lapping | a) a metalworking tool used to create an accurate sized hole |
| 2) cutting | b) a cutting process that uses a drill bit to cut or enlarge a hole in solid materials |
| 3) grinding | c) a material removal process in which a cutting tool takes mass and shapes a stationary object to produce a sculpted or plane surface |
| 4) shaping | d) an abrasive machining process that uses a grinding wheel as the cutting tool |
| 5) drilling | e) the division or separation of a physical object with an edged instrument |
| 6) honing | f) a part of the manufacture of almost all metal products, and it is common for other materials, such as wood and plastic, to be machined |
| 7) milling | g) the process of grinding grain or other materials in a mill |
| 8) machining | h) a machining operation that uses a metalworking tool with a series of chisel points mounted on one piece of steel |
| 9) reamer | i) a machining operation, in which two surfaces are rubbed together with an abrasive between them, by hand movement or by way of a machine |
| 10) broaching | j) machining a surface by scrubbing an abrasive stone against it |
1. The main features of the broach are the chip clearance, degree of taper or increase in height of each successive tooth, relief, tooth depth, and rake.
2. The heavier the feed per tooth or the longer the surface being broached, the greater must be the pitch or space between successive teeth for the chips to accumulate.
3. Knee-type machines are made with horizontal or vertical spindles.
4. Straight milling machines with fixed or sliding heads are otherwise similar to the horizontal type.
5. They are used for face or end milling and are frequently provided with a rotary table for making cylindrical surfaces.
6. These machines are usually provided with work-holding fixtures and may be constructed as plain or multiple-spindle machines, simple or duplex.
7. Thread millers are used to cut broach and worms.
8. A single formed cutter may be used or all the threads may be cut at one time by a multiple-thread cutter.
9. Threading dies, used to produce internal threads, may be solid, adjustable, spring-adjustable, or self-opening die heads.
10. These chasers may be of the radial type, hobbed or milled; of the tan- genital type; or of the circular type.
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| Read and translate the following text. | | | Choose the best alternative to fill in the gaps in each of the following sentences. |