International Correspondence Schools · Scranton, Pa. : The Colliery engineer co. · leaf 516
, which specially adapt it to certain situations.Stiff frogs contain much less material and require lessshop work than spring frogs. For a given angle a stifffrog requires less space, and hence is better adapted to yardwork than spring-rail frogs. They are more simply con-structed than spring… … Fig. 525. Figs. 525 and 526 represent the best types of stiff frogs.The frog shown in Fig. 525 is called a plate frog. The rails composing the frog are fastened to a plate of wroughtiron or steel a c d b by means of rivets through the railflanges, as shown in the figure. Square holes t\ f are 1100…
Railroad engineering
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