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RESCUE PULLEYS
A rescue pulley (Figure 32) has rotating side plates and is
constructed with a sheave (wheel) mounted on a bearing or
bushing. Pulleys constructed with sealed bearings are
superior and more efficient in handling rescue loads than
those containing bushings. When using a pulley as a
directional, keep in mind that the force on the pulley anchor
may be twice the force on the rope!
The tread diameter of the pulley sheave, where the rope
lays, is important to note. For efficiency, the optimum rescue Figure 32- Rescue pulley.
Rock Exotica Mini Machined
pulley size would be a tread diameter of at least three times Pulley (P21). © Rock Exotica.
the diameter of the rope being used on it. Some
manufacturers will state the outside diameter (OD), which could be misleading. Pay
42
attention to the tread diameter which relates directly to performance .
Figure 33- Pulley Types. © CMC Rescue and Rock Exotica.
42 Thompson, Rock. Personal communication.
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