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machine tools –

a measure of man's progress

the variety and combinations of machine tools today are unlimited. some of them are very small and can be mounted on a work-bench1 but others are so large that we have to construct special buildings to house them.

there are some basic operations at any workshop. they are turning, drilling, threading, etc. the main machine tool of such a workshop is the multipurpose lathe. what is a lathe? it is a power-driven machine22 with special tools which can cut or form metal parts. the metal that cuts another metal must be very hard and so tools should be made of very hard steel alloys. the tool itself is very small in comparison with the mechanism that is to direct it.

technological progress improves accuracy of machine tools. today's equipment can produce parts with very high accuracy. one can find a number of33 machine tools that can measure and inspect their production themselves – machine tools that are to handle the parts mechanically and automatically. such machines can hold the parts which are to be measured and are able to indicate precise measurements themselves. a great many of such “clever” machines can be found today in our industry.

since machine tools become faster and more complex, automatic measurements and inspection ought to be of greater importance. automation is one of the main factors of engineering progress.

flexible production lines form the basis for automated workshops. the main principle of such a flexible line is the fact that it can be switched over from one product to another, which has a similar structure but a different outline, almost instantaneously. it is equally efficient in conditions of both mass and small-batch production44 and will serve to increase the productivity.

12. ответьте на вопросы к тексту.

1. what types of machine tools are there nowadays?

2. what are the basic operations at a workshop?
3. what is a lathe?

4. why must tools be made of very hard steels and alloys?

5. is the tool itself big or small?

6. what improves the accuracy of machine tools?

7. what is one of the main factors of engineering progress?

8. what forms the basis for automated workshops?

9. what is the main principle of a flexible line?

anarazeynalova    2   30.10.2019 01:56    73