Differential pulley were. Next, the downward force acting on the lower pulley equal the upward forces acting on it, so Additionally, there is no net torque or moment around the compound pulley, so the clockwise torque is equal to the anticlockwise torque: Substituting "F" and "F" from the above equations, Rearranging gives As "F" = , Finally, the mechanical advantage, = or . Differential pulley A differential pulley, also called "Weston differential pulley", sometimes "chain hoist" or colloquially "chain fall", is used to manually lift very heavy objects like car engines. It is operated by pulling upon the slack section of a
Wire rope spooling technology the grooving on the drum. Alternatively, a sheave can be integrated and installed within the housing frame. In this case, the system can be set up anywhere around the drum. Oceanographic installations that spool rope up to 46 layers have demonstrated that level winders give synchronized and controlled spooling in the harshest, most testing conditions. Grooving systems for multilayer spooling can be carved onto steel shells that are mounted onto old drums, by either bolting or welding, as an outer sleeve. Called split sleeves, they can be retrofitted onto old drums or mounted on new drums to allow a future