Read the texts and translate them in writing. Use a dictionary
Text E
Efficiency in Engineering Operation
Unlike the scientist, the engineer is not free to solve problems which interest him. He must solve problems as they arise, his solution must satisfy conflicting requirements. Efficiency costs money, safety adds complexity, performance increases weight. The engineering solution is the optimum solution, taking into account many factors. It may be the cheapest for a given performance, the most reliable for a given weight, the simplest for a given safety, or the most efficient for a given cost. Engineering is optimizing.
To the engineer, efficiency means output divided by input. His job is to secure a maximum output for a given input or to secure a given output with a minimum input.
The ratio may be expressed in terms of energy, materials, money, time or men. Efficiency is achieved by using efficient methods, devices, and personnel organisations.
The need for efficiency leads to the large, complex operations which are characteristic of engineering. The processing of the new antibiotics in the test-tube stage belongs in the field of biochemistry. But when great quantities must be produced at low cost, it becomes an engineering problem. It is the need for efficiency and economy that differentiates ceramic engineering from the work of the potter, textile engineering from weaving, and agricultural engineering from farming.
Since output is input minus losses, the engineer must keep losses and waste to a minimum. One way is to develop uses for products which otherwise would be waste.
Losses due to friction occur in every machine and in every organisation. Efficient functioning depends on good design, careful attention to operating difficulties, and lubrication.
The raw materials with which engineers work seldom are found in useful forms. Engineering of the highest type is required to conceive, design and achieve the convertion of the energy of a mountain stream into the powerful torque of an electric motor. Similarly, many engineering operations are required to change the sands of the
seashore into the precise lenses which enable us to observe the microscopic amoeba in a drop of water. In a certain sense, the successful engineer is a person always trying to change things for the better.
Text F
Metallurgical techniques
Some of the most widespread early metallurgical techniques evolved around the use of copper, the first industrial metal. The earliest use of natural copper involved an extremely limited Stone Age technique by which small, specially selected pieces of metal were made into beads, awls, pins, or hoops by cold forging, a technique that consisted simply of hammering the cold metal. Early attempts to coldhammer small pieces of natural copper were able to give only a limited improvement to such pieces.
The stone-working techniques (such as simple shaping) found greater success when smiths learned to produce copper of a more malleable form by the process of annealing: exposing the copper to a slow, softening heat. Annealing was a step toward the subsequent melting, or smelting, of cooper. When smiths discovered that melted pieces of copper can form a single puddle that hardens upon cooling, they were able to use small scrap pieces of metal that would otherwise have been unusable
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Metals came into limited use 5 500 years ago Copper nuggets and meteoric iron, as well as gold and silver, were also used in that time. Gold, in the form of nuggets was pounded into crude ornaments with a stone hammer. (Unlike copper, gold did not harden appreciably with this pounding, and therefore could not be used to make tools.) Silver nuggets were also used to make rings, bracelets, and other fine ornaments, but not so extensively as gold.
Text G
THE PIONEERS
Karl Benz (18441929), the son of a railway engine-driver who died when Karl was two, studied engineering at the Karlsruhe Polytechnic. After various jobs he set up business, with successive partners in a very small way making two-stroke gas engines of his own design in 1880. Although he is entitled to be called the "inventor of the petrol car" he was reluctant to depart from his original design of belt-driven horseless carriage which sold well in 1890s. Other designers were called in, and after 1902 Benz had little influence on the development of the motor car.
Frederick William Lanchester (18681946), the son of an architect, made Britain's first four-wheeled petrol car of wholly native design in 1895 with the help of his brother George. A small company was formed and production was begun late in 1899. Lanchester's designs were always unique and ahead of their time; he was responsible for many innovations which became accepted some years later. Those include a vibrationless, fully balanced engine, splined shafts, full-pressure lubrication, lightweight pistons, disk brakes and more. "Doctor Fred" was also a pioneer authority and writer on aerodynamics, and for many years Consultant Engineer to the Daimler Co.
Henry Ford is usually credited with "inventing" mass production, yet the idea originated many years earlier in the Connecticut clock trade and was developed in the America's small-arms industry.
Text H
HENRY FORD (1863-1947)
Most people credit Henry Ford with inventing the automobile. The fact is he didn't such a complex machine is the result of a combination of technologies developed by many people over time. He did, however, invent the assembly line, which revolutionized the way we make cars, and how much they cost.
In 1908, Ford's company began selling his famous Model T for $850 each. The Model T was inexpensive for its day. and proved to be reliable and easy to operate. It quickly became very popular: and soon Ford found he was unable to meet the enormous demand for his cars.
Ford's solution was to invent a moving industrial production line. By installing a moving belt in his factory, employees would be able to build cars one piece at a time, instead of one car at a time. This principle, called "division of labor", allowed workers to focus on doing one thing very well, rather than being responsible for a number of tasks.
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Ford found his new system produced cars quickly and efficiently; so efficiently that it considerably lowered the cost of assembling the cars, He decided to pass these savings along to his customers, and in 1915 dropped the price of the Model T to $290. That year, he sold 1 million cars.
Unit 2
Ferrous Metals
I. Language
Ex. 1. Remember the following words and word combinations:
| machine-building industr y engineering metal ferrous metal non-ferrous metal tool steel iron cast iron grey iron alloy cast iron malleable iron casting foundry mould shop alloy part content carbon silicon phosphorus manganese sulphur to reduce to solidify to confine to machine to anneal to pour bed plate wheel grade strength shrinkage brittle on account of | , , . , , , , , , | , , . , , , , , , , - |
