Practical Marine Engineering for Marine Engineers and Students; With AIDS for Applicants for Marine Engineers' Licenses
William Frederick Durand
Paperback
(RareBooksClub.com, March 6, 2012)
This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 Excerpt: ...is contact between piston and head. A mark is then made on the guide corresponding to that on the crosshead. The parts are then lowered down as far as they will go, or until there is contact between the piston and the lower head, and anothef mark is made on the guide corresponding to that on the crosshead. The distance between these is then taken, and from it is subtracted the length of stroke. The remainder is then divided between the two clearances, top and bottom. Midway between the two inner points a point may be placed to indicate the location for mid or half stroke. Thus, if the stroke is 36 inches and the distance found as above is 37 inches, the 1 inch difference is to be divided between the two clearances, giving to the upper, say, 7-16, and to the lower 9-16 inch. These differences are then laid off within the outside marks, and the points thus given will serve at any time as a guide for the adjustment regarding clearance proper, while the movement of the piston may be readily brought to conform to these limits by suitable adjustment of the liners or chock pieces in the joints and bearings of the connecting rod and crank-shaft. The 36 inches may then be divided equally and the mark placed to show mid stroke, such a point being sometimes of use in connection with the setting of the valve. Another method of determining the clearance which is available when the cylinders have manholes is as follows: The manholes are removed and a number of balls of stiff red lead or other putty and faced with plumbago are distributed on the top of the piston and on the inside of the lower head. The engine is then given a revolution by means of the turning engine and the balls are collected. This method serves to show just how the clearance is distributed, and is ther...