Hill, John A. (John Alexander), 1858-1916, Sinclair, Angus, 1841-1919 · New York : American Machinist Pub. Co · leaf 306
When the retaining valve is cut inand brakes released, action of theretaining valve retains about 20pound* pressure in brake cylinder,i.r.. prevents that amount from escap-ing into atmosphere. Retaining thisamount keeps piston in action, sothai brake shoes rest fairly againstthe wheels, and exert a…
Railroads · Locomotives
Internet Archive · Carnegie Library of Pittsburgh · Public Domain Mark 1.0. Free to use for anything.
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