  When a solid pulley is to be removed from a piece of shaft for any reason, it is not good policy to use sledge hammers on the spokes or hub to do it. Cast iron in pulleys is too liable to break or crack under repeated blows. Fig. 59. In Fig. 59 one ready method is illustrated by which the pulley may be removed. When a place between two walls can be found that will admit of this arrangement, proceed as shown to force the shaft through the pulley, substituting longer pieces of pipe as the shaft is forced through farther. In one case where a large pulley was stuck on a 7-inch shaft and its removal was imperative, the shaft was sawed off (with large hack-saws) close up to the pulley hub and two 5/8-inch holes were drilled into the shaft parallel to its axis, as shown in Fig. 60. These holes were drilled so that they were 90 degrees apart and came within 1/16-inch of the hub of the pulley. The hub was 14 inches through and these holes were 8 inches deep; but that was enough to loosen up the shaft so that when the pulley was laid over on beams with Another way to remove a pulley is shown in Fig. 61, where a ram is used. The ram is another piece of old shaft. To prevent its damaging the pulley hub and also to have its force applied most advantageously, it should be used in a direct line with the direction of removal. To do this, the method shown in Fig. 61 is self-explanatory. Fig. 60. Another good method of removing an obdurate pulley is illustrated in Fig. 62, where the bolts W, W must have long threads and the work is done by pulling up on the nuts A, A. This method can be used only when the end of the shaft can be reached and used as shown. In using this method, care must be exercised Fig. 61. If the pulley comes extra hard, it can be assisted when the strain is on the bolts by striking at X with a sledge. A good device for removing motor and generator pulleys that are near the shaft end is shown in Fig. 63. The arms Z, Z are adjustable to take hold of hub or arms, and the screw applied to the shaft center will do the rest. To run a pulley off a shaft without injury to the hands, use a monkey wrench on the rim of each pulley, as shown in Fig. 64. One pulley on the shaft can be selected for a hold-back; one monkey wrench there will hold the shaft from turning, while the other will turn around the shaft the pulley which it is intended to remove. Fig. 63. Fig. 64. VIII |
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