2.3. Choice of rational machine type.
Correct choice of machine type reduces range of products, increases seriation of output, widens possibilities of production mechanization and automation and introduction of production mechanization and automation and introduction of progressive methods of production with appropriate increase of productivity, lowering of production cost of product and improvement of its quality. Dissipation of re sources for small-lot production is eliminated, repair and spare supply are simplified.
This problem can be solved by the following methods: creation of parametrical series of machines with rationally selected interval between each of them; increase of machine universality, i.e. expansion of the range of functions performed; putting reserves of development into design and successive using of these reserves as the demands grow.
All methods can be combined with each other and with methods of unification. Thus parallel creation of unified and parametrical series of piston internal combustion engines (ICE) is possible; unified series consisting of ICE with similar cylinders but with different number and position of them, and parametrical series consisting of ICE with the same number and position of cylinders, but possessing another diameter.
Translate the following words into Russian:
Rational machine type, reduce range of, increase, seriation of outpu4-widens, appropriate, production cost, improvement of, quality, dissipation, resources, small-lot production, eliminated, repair, spare supply, simplified, solved, parametrical series, interval, the range of, -successive using, the demands grow, unification, creation of unified, piston internal combustion engines, ICE, cylinders.
Give English equivalents for:
Рациональный, сокращает, номенклатура, серийность, выпуск, автоматизация, внедрение, соответствующий, качество, устраняться, распыление, средства, облегчается, эксплуатация, ремонт, :набжение, запасные, задача, решается, следующими способами, параметрических рядов, рационально, выполняемых, обязанность, резерв, развитие, последовательным, использование, мера, рост, потребность, сочетать, унификация, параллельное, поршневой двигатель внутреннего сгорания, одинаковый, цилиндры, расположение, диаметр.
Questions to the text:
l.What does the correct choice of a machine type lead to? Give examples?
2.Can the creation of parametrical series of machines with rationally selected interval between each of them and the increase of machine university help to solve this problem?
З.Сап the above methods be combined ? Give examples?
4.What does ICE mean?
2.3.1. Parametrical Series.
Series of machines with the same specification and possessing indexes and index gradation, regulated by a design, are called parametrical series. In many cases it is advisable to put a common type of machine into basis, receiving the required gradations by means of alteration of its dimensions alongside with keeping geometrical similarity of series modification unchanged. Such series are called dimension-similar or simply dimension ones.
In the other cases it is advisable to set a type of machine with its own dimension for each gradation. Such series are called standard size series. Ship engines are applied, with middle and great powers-2-step ones, possessing smaller overall dimensions and mass with equal powers, or gas-turbine engines, capable of even more concentration of power are applied.
Fig 2.8. Diagram of parametrical series usability of 3-phase alternative current engine:
I-arithmetic series;
II-geometric series;
III-series, coordinated with usability curve.
Назад Оглавление Вперед