All About Engines
Forfatter: Edward Cressy
År: 1918
Forlag: Cassell and Company, LTD
Sted: London, New York, Toronto and Melbourne
Sider: 352
UDK: 621 1
With a coloured Frontispiece, and 182 halftone Illustrations and Diagrams.
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CHAPTER VI
Steam Turbines
THE primitive steam engines devised by Hero and
Branca, which were described in Chapter II.,
differed from the engines which have just been
described in the fact that rotary motion was obtained
without the use of reciprocating parts. The use of a
piston by Papin turned men’s minds into another
direction, and the success of Newcomen and Watt
completely eclipsed for a hundred years the older
ideas. But this does not mean that they were for-
gotten entirely. Most engineers would have admitted
the disadvantage of starting and stopping the motion
of heavy masses of metal twice in every revolution, and
many—even Watt himself—sought long and earnestly
for some means of converting the energy of steam
directly into rotary motion. For nearly a hundred
years the Patent Office Records were studded with
unsuccessful efforts, and it was not until 1884 that
anyone approached within measurable distance of
success. In that year the Hon. C. A. Parsons patented
a “ reaction ” turbine, and in the year following the
Swedish engineer, Dr. Gustaf de Laval, patented
one of the “ impulse ” type. The initial difficulties
were very great, and for some years progress was
slow and tentative. But when the difficulties of
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