Pulley forces on the moving block must sum to zero. In addition the tension in the rope must be the same for each of its parts. This means that the two parts of the rope supporting the moving block must each support half the load. These are different types of pulley systems: The mechanical advantage of the gun tackle can be increased by interchanging the fixed and moving blocks so the rope is attached to the moving block and the rope is pulled in the direction of the lifted load. In this case the block and tackle is said to be
Wire rope spooling technology pattern is engineered to suit the rope's length, diameter and construction type. In any multi-layer spooling application it is important that when the rope is first installed on the drum, it is done so under tension to avoid any slack on inner layers that can be crushed or nicked against the groove walls by outer layers. The fleet angle is defined as the largest angle of the rope between the first sheave and the drum flange, relative to the centre line of the drum. With all type of drums, the rope is subject to a fleet angle which impacts on