Техническое чтение для энергетиков. Бухарова Г.П. - 84 стр.

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86
having to be cooled and reheated with each cycle; he even put a steam jacket around
of the fuel which the Newcomen engine needed. He also closed the upper end of the
cylinder, which was open in the Newcomen engine, and built around the piston rod
what is now called a stuffing-box; instead of making the air push the piston down he
used steam for this purpose too, introducing it above the piston as well as below in
the cylinder. The fourth of his improvements was an air pump to maintain the
vacuum on his condenser by pumping out the condensed water and air from it.
Watt's first model was single acting and could be used only for pumping. But a
great many tasks were awaiting the steam-engine. New machines in various branches
of industry needed power; goods were to be moved, people transported.
A manufacturer from Soho, near Birmingham, Boulton, made James Watt his
partner in the world's first steam-engine factory. Soon the firm of Boulton & Watt
became one of the wonders of the age: here the visitors, who turned up from all over
Europe and even America, could see the shape of things to come.
Boulton made Watt think of ways and means to convert the reciprocating
movement of the engine into a rotary one for use in factories and, later perhaps, for
vehicles and ships. Watt produced no less than five different solutions, the best of
them being the 'sun-and-planet' system – we are so familiar with it that we hardly
realize what an excellent solution to a tricky problem it is. Watt also adopted an old
invention, the fly-wheel, for the important purpose of turning the irregular motion of
the piston into a regular, rotary one. The fly-wheel is, in fact, a reservoir of energy,
which it 'stores up' during the working stroke of the engine, to release it as the crank
passes through the dead centre.
Neither could he have known that he invented one of the major 'feed-back'
devices–which play such a vital part in automation, where they act as automatic
controls. This is the 'governor', whose task it is to keep the engine speed constant,
detect an unnecessary or dangerous increase of engine power, and to reduce it by
closing the throttle or steam-valve. The Watt governor works simply by using
centrifugal force: a vertical shaft, carrying two heavy metal balls at the ends of arms,
is rotated by the engine, and centrifugal force moves the balls outwards as the engine
speed increases, or allows them to sink as the speed decreases. The arms to which the
balls are fixed move therefore up or down, raising or lowering a 'collar' around the
vertical shaft. This is connected to the throttle or steam-valve, closing or opening it if
the engine speed becomes too great or too low. Thus the steam-engine controls itself.
'The people of London, Manchester, and Birmingham are steam-mill mad',
Boulton told Watt in 1781. The Soho factory turned out as many steam-engines as
possible, yet the demand surpassed by far its production capacity, and other
manufacturers' were permitted to build them under Watt's licence. Why was there
now such an enormous demand for energy, after centuries of indifference and even
hostility towards the idea of Using the forces of Nature for benefit of mankind?
Slowly, the medieval system of the individual craftsman had begun to crumble.
In England a new form of industry appeared, timidly at first: groups of men banded
together to use machines which were too costly and too heavy for the independent
artisan. Merchants' who needed wares to sell provided the money and organized the

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