Агабекян учебник для тех.вузов. Агабекян учебник для тех. Агабекян И. П., Коваленко П. И. Английский для технических вузов
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Text D: «DIES»Dies are tools used for the shaping solid materials, especially those employed in the pressworking of cold metals. In presswork, dies are used in pairs. The smaller die, or punch, fits inside the larger die, called the matrix or, simply, the die. The metal to be formed, usually a sheet, is placed over the matrix on the press. The punch is mounted on the press and moves down by hydraulic or mechanical force. A number of different forms of dies are employed for different operations. The simplest are piercing dies (пробивной штамп), used for punching holes. Bending and folding dies are designed to make single or compound bends. A combination die is designed to perform more than one of the above operations in one stroke of the press. A progressive die permits successive forming op erations with the same die. In coining, metal is forced to flow into two matching dies, each of which bears a engraved design. Wiredrawing Dies In the manufacture of wire, a drawplate (волочильная доска) is usually employed. This tool is a metal plate con taining a number of holes, successively less in diameter and known as wire dies. A piece of metal is pulled through the largest die to make a coarse wire. This wire is then drawn through the smaller hole, and then the next, un til the wire is reduced to the desired measurement. Wiredrawing dies are made from extremely hard mate rials, such as tungsten carbide or diamonds. Thread-Cutting Dies For cutting threads on bolts or on the outside of pipes, a thread-cutting die (резьбонарезная плашка) is used. It is usually made of hardened steel in the form of a round plate with a hole in the centre. The hole has a thread. To cut an outside thread, the die is lubricated with oil and simply screwed onto an unthreaded bolt or piece of pipe, the same way a nut is screwed onto a bolt. The correspond ing tool for cutting an inside thread, such as that inside a nut, is called a tap (метчик). Vocabulary: chip — стружка sharp — острый friction — трение content — содержание range — диапазон inexpensive — недорогой to permit — позволять, разрешать common — обычный tungsten — вольфрам ingredient — ингредиент diamond — алмаз tips — наконечники ceramic — керамический truing — правка, наводка, заточка die — матрица, штамп matrix — матрица to employ — применять to pierce — протыкать, прокалывать to punch — пробивать отверстие matching — сочетающийся, парный coarse — грубый wire — проволока to draw — тащить, волочить thread — резьба hardened — закаленный to lubricate — смазывать to screw — привинчивать nut — гайка outside — наружный, внешний inside — внутри, внутренний Exercise 4.4. Find English equivalents in the text: 1. удалять металлическую стружку 2. острый режущий край 3. содержание углерода 4. режущая способность 5. сталь для скоростного резания 6. правка шлифовальных кругов 7. гидравлическое или механическое давление 8. различные формы штампов Exercise 4.5. Translate the following sentences into Russian: 1. Все резцы и фрезы должны иметь острую режу щую кромку. 2. Во время резания режущий инструмент и деталь имеют высокую температуру и должны охлаждаться. 3. Углеродистые стали часто используются для из готовления резцов потому, что они недорогие. 4. Быстрорежущие стали содержат вольфрам, хром и ванадий. 5. Алмазы используются для резания абразивных материалов и чистовой обработки поверхности твер дых материалов. 6. Для различных операций используют различные штампы. 7. Волочильные доски для проволоки делаются из очень твердых материалов. 8. Резьбонарезные плашки и метчики используют ся для нарезки резьбы снаружи и внутри. FAMOUS PEOPLE OF SCIENCE AND ENGINEERING George Stephenson George Stephenson was a British inventor and engi neer. He is famous for building the first practical rail way locomotive. Stephenson was born in 1781 in Wylam, near New castle upon Tyne, Northumberland. During his youth he worked as a fireman and later as an engineer in the coal mines of Newcastle. He invented one of the first miner's safety lamps independently of the British inventor Humphry Davy. Stephenson's early locomotives were used to carry loads in coal mines, and in 1823 he estab lished a factory at Newcastle for their manufacture. In 1829 he designed a locomotive known as the Rocket, which could carry both loads and passengers at a greater speed than any locomotive constructed at that time. The success of the Rocket was the beginning of the construc tion of locomotives and the laying of railway lines. Robert Stephenson, the son of George Stephenson was a British civil engineer. He is mostly well-known known for the construction of several notable bridges. He was born in 1803 in Willington Quay, near New castle upon Tyne, and educated in Newcastle and at the University of Edinburgh. In 1829 he assisted his father in constructing a locomotive known as the Rocket, and four years later he was appointed construction engineer of the Birmingham and London Railway, completed in 1838. Stephenson built several famous bridges, includ ing the Victoria Bridge in Northumberland, the Britan nia Bridge in Wales, two bridges across the Nile in Damietta in Egypt and the Victoria Bridge in Montreal, Canada. Stephenson was a Member of Parliament from 1847 until his death in 1859. |