Twentieth century handbook for steam engineers and electricians, with questions and answers; a practical nontechnical treatise .. (1916)
Swingle, Calvin F. (Calvin Franklin), b. 1846 · Chicago, F.J. Drake & company · leaf 479
shows the spring. 466 Steam Engineering If the engine is a non-condensing engine the pencil intracing the diagram will, or at least, should not fall belowthe atmospheric line at any point, but will on the returnstroke trace a line called the line of back pressure at a dis-tance more or less above… … Fig. 162crosby indicator spring distance this line is below the atmospheric line will dependupon the number of inches of vacuum in the condenser. As before stated, the length of stroke of the indicatorpiston, and the pencil movement as well is controlled by aspiral steel spring which acts in…
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