I. Перепишите и переведите текст письменно.
The lathe generally is considered to be the primary machine tool, both because it will do a greater variety of work than any other tool and because almost any other kind of machine tool may be manufactured with the lathe. Modern lathes are highly efficient, accurate and complex devices, capable of doing a great quantity and variety of work. A well constructed engine lathe when properly operated, produces work accurate within 0.001 of an inch or even less.
The size or capacity of a lathe is given in terms of swing and length of bed. The swing refers to the diameter of work to be rotated in the lathe. Тhе length of a lathe shouldn´t be confused with the maximum distance between centres when the tailstock is moved to the rear end of the lathe bed. The maximum distance between centres, however, determines the length of the stock to be machined.
Lathes are made in a variety of types and sizes from the small precision lathe found in watch repair shops to the immense machines used in manufacturing big guns. In recent years manufacturers have produced attachments to be employed on a lathe to perform functions or operations formerly done on a special machine a milling attachment, a boring attachment, and a gear-cutting attachment. Such devices greatly extend the variety of work that can be performed on a lathe.
Lathes in general being used for a great variety of operations, naturally there are many different designs and sizes. The various types are usually classified either with respect to some characteristic constructional features or with reference to the general class of work for which the lathe was designed, the most common type of lathe being usually known by manufacturers as an engine lathe or lathe.
Speaking about the types of lathes one cannot help mentioning the automatic lathe. In these lathes all the tool movements are automatically controlled although the work must be inserted and removed by an operator.
II. Проанализируйте и письменно переведите следующие предложения.
1. The tool should be harder than the material which it is to cut.
2. A hole being drilled, the material is removed in the form of chips.
3. The bench lathe proves to be a universal machine especially suitable for the production of small parts.
4. We know grinding to be a process of removing metal by means of an abrasive wheel.