The Mechanical Handling and Storing of Material

ROPEWAYS 279 The two surfaces which come in contact with the rope have two wart-like projections, each of which fasten between the coils of the rope and prevent any slip. One of the features of this system is the groups of balanced sheaves which were first introduced for supporting the rope. Illustrations of their single, pair, and multiple balanced beams and sheaves are shown in Figs. 402, 403, and 404, Fig. 406. Ordinary Bucket for Ore, Coal, etc. Fig. 407. Carrier for Barrels, Sacks, etc. Grouping sheaves in this manner simplifies the construction of ropeways, and enables long spans to be worked without undue pressure on the supporting sheaves, as the balanced beams allow the sheaves to adjust themselves and follow the angle caused by the rope passing over them, so that by this means the pressure is equally divided all the time on every sheave with no detrimental effect on the rope. An example of this kind Fig. 408. Carrier for Timber. may be cited in the installation for the Tominil Mexican Mining Co. 1 he ropeway in this instance is 2,400 m. in length, and runs over a series of rugged ridges, and only eight trestles of 3 m. each in height are employed for supporting the rope, the longest span being 810 m. A very similar line on the same system is now in course of construction in Bolivia, where one span measures over 1,000 m. between supports.