Mechanical Advantage Systems

TOPIC: MECHANICAL ADVANTAGE SYSTEMS TIME REQUIRED: THREE HOURS MATERIALS: ROPE, WEBBING, HARNESSES, CARABINERS, FIGURE EIGHTS, ASCENDERS, PULLEYS, PRUSSIC CORDS, SLINGS, PICKETS, SLEDGE HAMMER REFERENCES: RESCUE TECHNICIAN, MARYLAND FIRE...


        the load

  19. Load being moved outward should have the pulleys placed as close together as possible since

        they will be moved outward as the load moved; the brake may need to be set to move the pulleys

        closer

 

IV. PRACTICAL ACTIVITY (1-4)

A. Set up three practical skills stations with an evaluator at each station to observe skills proficiency. Divide the class evenly into three groups. The anchor points for Stations 2 and 3 should already be in place.

B. Station 1 - Knots and Anchoring to Objects

     0 Have each student tie the following knots with safety knot

            . Water knot

           . Bowline

           . Clove hitch

           . Figure eight family - Figure eight on a bight, Figure eight reweave, and Figure eight bend

     0 Have each student demonstrate the following methods of anchoring to an object

            a. Single point with rope and webbing

            b. Tensionless with rope

            c. Multiple points

      0 Have the students construct a three-picket system

NOTE: The knot tying and anchoring can be done in conjunction with one another.

C. Station 2 - Constructing a Z-Rig Mechanical Advantage System

  1. Have the students construct a Z-rig system

  2. Have the students use the Z-rig system to move an object inward and outward

  3. Have the students add another pulley and see if less effort is required to move the object

D. Station 3 - Constructing a Piggy-Back Mechanical Advantage System

  1. Have the students construct a piggy-back system

  2. Have the students use the piggy-back system to move an object inward and outward

  3. Have the students add another pulley and see if less effort is required to move the object

NOTE: All students are expected to perform all the practical skills to the satisfaction of the evaluators. Assistance should be provided when required.

 

REVIEW:

Mechanical Advantage Systems

   * Rope Software and Hardware

   * Anchor Points and Use

   * Constructing Mechanical Advantage Systems

   * Practical Activity

REMOTIVATION: Knowing how to quickly and efficiently construct a mechanical advantage system will result in less physical effort required as well as speed up the work process.