Twentieth century handbook for steam engineers and electricians, with questions and answers; a practical nontechnical treatise on the care and management of steam engines, boilers and electric machinery (1922)
Swingle, Calvin Franklin, 1846- [from old catalog] · Chicago, F. J. Drake & company · leaf 480
the indicatorpiston, and the pencil movement as well is controlled by aspiral steel spring which acts in resistance to the pressureof the steam. These springs are made of different tensionsin order to be suitable to different steam pressures andspeeds, and are numbered 20, 40, 60, etc., the… … Fig. 163 improved tabor indicator with outside connected spring Ashcroft Mfg. Co., N. Y. of one inch. Thus, if a number 20 spring is used and thepressure in the cylinder at the commencement of the stroke 468 Steam Engineering is 20 lbs. per square inch, the pencil will be raised oneinch;, or if the…
