Steam engines, prepared in the Extension division of the University of Wisconsin (1919)
Shealy, Edward Marvin · New York, McGraw-Hill · leaf 180
vement of the valve. In thisway the valve opens quicker and wider and there is less frictionbecause of the smaller valve travel. One of the ways in which these results have been accomplishedis by the use of double ported and multiple ported valves. The double ported valve illustrated in Fig. 100 is… … Fig. 100. entirely through the valve from one side to the other. The bot-toms of the chambers A and A are open so that steam may flowfrom them into the ports. The ports have two openings soarranged that when the outside edge of the valve uncovers oneopening the chamber A or A uncovers the other…
Steam-engines
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