Page 454 - Moving the Earth_ The Workbook of Excavation
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BLASTING AND TUNNELING
9.54 THE WORK
includes a ladder, electric and high-pressure air lines, water pump discharge pipe, and ventilator
ducts, all of which must be protected from swinging loads or falling chunks.
The headframe is a tower of prefabricated steel, as in Fig. 9.43, or may be built with timbers.
This carries the hoist sheaves, dumping mechanism, and the discharge chute or hopper. The hoist
engine and winch are ordinarily in a separate structure nearby.
FIGURE 9.43 Shaft and heading equipment.
