360 



STEEL HEAD FRAMES AND COAL TIPPLES. 



CHAP. X. 



type, and is 107 ft. from the collar of the shaft to the center of the sheaves. The main tower of 

 the head frame has six posts made of 4 Z's 3 in. X 2 fl in. X f in. with one plate 6 in. X f in. The 

 back braces consist of three columns having the same section as the main posts. The head frame 

 is fully cross-braced with angle struts, as shown in Fig. 22. The batter of the main tower columns 

 is I in. in 12 in., while the back brace makes an angle of 30 degrees with the vertical. The sheaves 

 are 10 ft. in diameter and are supported on I-beams, resting at the end nearest the engine house 

 on a built-up frame of angles and plates carried on two 15 in. I-beams, so as to make the necessary 

 clearance for the sheaves. The roof trusses above the sheaves carry two I-beams, on the lower 

 flanges of which are trolleys arranged for the attachment of chain blocks for placing and re- 

 placing the sheaves. The shipping weight of structural steel, including the corrugated steel, was 

 569,500 Ib. 



TABLE VI. 

 DATA ON STEEL COAL TIPPLES. 



The coal is hoisted in self-dumping cages which dump the coal into distributing chutes, in 

 which it runs by gravity to the bins having a capacity of 800 tons. The coal, being all used for 

 making coke, is not screened or weighed. 



The storage bins are built with a steel framework and are lined with \ in. buckle plates on 

 the sides, and have a f in. plate floor. The sides are supported by the 15 in. I-beams @ 42 Ib., 

 spaced 3 ft. 5i in. center to center. The inclined bottom framing consists of girders having 48 

 in. X | in. web plates and flanges composed of two angles 6 in. X 6 in. X TS in., and are tied together 

 with ties consisting of two angles 8 in. X 8 in. X f in. and one plate 17 in. X 2 in. at the bottom, 



