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 389
FiG.v lis the width of each steam port to be ll^ inches and the out-side lap to be 1 inch. In Fig. 118 the valve is at the ex-treme end of. its travel towards the right and is about toreturn. It first covers port number one=li4 inches. Nextit moves to mid travel lap number one=2i/4 inches. Itsnext… … Fig. 119 uncovers port number two=4i/2 inches, which is its travel.To return to the third function of the valve or cut off,Tig. 119. The crank has now traversed 120°, and the high-evSt point of the eccentric is at 60° on the return circle, apoint equivalent to 240° of the circle described by…
