Mechanical Advantage Systems Rope Rescue

For example a 2 1 or 3 1 system these are pronounced as a 2 to 1 and 3 to 1.

Mechanical advantage systems rope rescue.

However once you learn how to stack a 2 1 on a 2 1 to create a compound 4 1 you ll know how to stack a 2 1 on a 3 1 to create a 6 1 also a less popular system but worth knowing if you are a rigging geek and how to. Components of a mechanical advantage system. A raising system using a combination of pulleys to leverage the force applied in lifting is referred to as a mechanical advantage m a system. It requires less rope than a non piggybacked 2 1 system is reasonably easy to rig is easy to add a progress capture device provides an appropriate amount of mechanical advantage to raise one or two people and with a few tweaks it can be converted into a simple 5 1 system.

The first number represents the force on the load and the second number is the force that the rescuers are pulling on the rope. In a 3 1 mechanical advantage system mas a 300 lb load would feel like 100 lbs and 3 feet of rope will move the load up 1 foot. Notice however that the end of the rope on 2 1 systems is attached to the anchor whereas the end of the rope on 3 1 systems is attached to the load. Four to one systems are less popular than 3 1 systems probably because they require an additional pulley and don t offer significantly more mechanical advantage.

A system s mechanical advantage is expressed as a ratio using a colon. Understanding how mechanical advantage is calculated will help you create the perfect pulley configuration for any rescue mission you re up against. 3 1 system the 3 1 is the classic mechanical advantage system used by rescuers. Whether the end of the rope connects to the anchor or to the load is a subtle difference between mechanical advantage systems that have an even number e g 2 1 4 1 6 1 etc and systems that.