Е. С. Закирова, П. А. Красавин Английский язык для технических вузов



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T A Karpova Anglysky dlya tekhnicheskikh vuzov (1)

MODULE 9
A LATHE 
The turning processes are typically carried out on a lathe. It is consid-
ered to be the oldest machine tool. A workpiece of some material is rotated 
on a lathe so that when abrasive, cutting or deformation tools are applied 
to the workpiece, it can be shaped to produce an object with the rotational 
symmetry about an axis of rotation. Turning usually uses simple single-point 
cutting tools. The operations that can be performed with a single-point tool 
on a lathe are chamfering, parting, threading, boring, drilling, knurling.
A lathe can be of four different types such as straight turning, taper turn-
ing, profiling and external grooving. They can produce various shapes of work-
pieces, such as straight, conical, curved, and grooved. Each group of work-
pieces has an optimum set of tools operations which have been developed 
through the years.
Modern computer numerical control (CNC) lathes and CNC machining 
centres can do also other operations, e.g. milling by using driven tools. Most 
modern CNC lathes are able to produce most objects in 3D.
MODULE 10
BUSES AND COACHES
Buses (also called omnibuses) are designed to transport about forty pas-
sengers. In towns and cities there are usually short distances between stops, 


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and speed of loading and unloading passengers is very important. The entrance 
step to the bus is about 300 mm above the road and it provides an easy step 
up. Another step up leads to the deck of the bus. The doors are usually power-
operated by the driver to prevent passengers getting on or off while the bus is 
moving. A double-decker bus is carrying about sixty passengers. In modern 
designs the entrance is at the front for the driver to have a direct view of board-
ing passengers.
A coach is a type of a bus for conveying between thirty and forty passen-
gers on excursions or for fairly long distances between towns and even coun-
tries. Unlike buses designed for shorter journeys, coaches have a luggage hold 
separate from the passenger cabin and are normally equipped with facilities re-
quired for longer trips: comfortable seats, air-conditioning, overhead luggage 
compartments, small tables for small snacks, video screens to show movies, 
and sometimes even a toilet.


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