Advanced Rigging (BOOM VOC) Exam Questions with Right Rationales Graded A+.

  The response of objects to the application of forces, movements or torques. - Answer: What is meant by the term "Dynamics"? The boom is positioned between the two rearmost outriggers or tracks. - Answer: If a crane quadrant is defined as "Over the Rear", what does this mean? The boom is positioned between two of the side outriggers or over one track. - Answer: If a crane quadrant is defined as "Over the Side", what does this mean? The boom can swing 360 degrees around the crane and remain within the given load rating. - Answer: If a crane quadrant is defined as "360 degrees", what does this mean? 75% - Answer: When considering a multiple crane lift, neither crane can exceed what percent of their load chart? Only one. Relay signal persons may be used, but they respond to a single, primary signal person. - Answer: During a tandem lift, how many signal persons are used? Pulling a hoist line sideways can overload or side load a crane and cause the crane to collapse. - Answer: Why is it important that both cranes keep their hoist lines vertical at all times during a tandem lift? Stacking blocks of wood perpendicular to one another, tightly together with no spacing. - Answer: What is cribbing? Inclined planes - Answer: Ramps are also known as _____. They will need to calculate the coefficient of friction (CF) and include that in their planning calculations. - Answer: Why is it important for riggers to know the materials that the inclined plane is made from? 394 pounds of line pull - Answer: Use the inclined plane formula to calculate the line pull needed to pull a 500 pound steel box up a 10' aluminum ramp, 2 feet onto a loading dock with a run of 9.8 feet. They are meant to sustain the squeezing of the slings during a lift. This is why they cannot be use under loads to lift them. - Answer: Why are spreader beams designed more for compression loads than vertical loads? Rebar is both heavy, long and flexible. It often needs spreader bars to prevent excessive sagging. - Answer: How is rigging rebar different than rigging other long materials? 30, at least half the length of the rebar long. - Answer: When lifting rebar longer than _____ feet, a spreader bar should be used. The spreader bar should be _____ long. Tag lines; at the end but not attached to the bundling wire. - Answer: _____ should be used when hoisting rebar in congested areas and it should be attached _____. double wrap; same - Answer: When choking rebar bundles, riggers should use a _____ choker and choke the rebar in the _____ direction. When a flexible steel wire rope is used to support a hung scaffold, what is its maximum allowable load? - Answer: One sixth of the breaking load What is the minimum width of a heavy duty platform? - Answer: 900mm or 4 boards What is the maximum cradle width for a double rope suspended scaffold? - Answer: 1.7 metres Can bags of sand be used to counterweight a needle? - Answer: No Would you use bulldog grips to secure a suspension rope? - Answer: No You are required to hang a chain block to lift a load. The chain block will be supported from an inverted snatch block on a span rope fixed between two beams? (A) The span between the beams is 30 metres. The weight of the load is 750kg. The weight of the lifting gear and load hauling part is 60kg. Calculate the tension in the span rope when the sag is at its recommended minimum. - Answer: ((750+60) x 30) / (4 x 1.5) = 4050 kg You are required to hang a chain block to lift a load. The chain block will be supported from an inverted snatch block on a span rope fixed between two beams? The span between the beams is 10 metres. (B) The weight of the load is 500kg. The weight of the lifting gear and load hauling part is 50kg. Calculate the tension in the span rope when the sag is at its recommended minimum. - Answer: ( (500+50) x 10) / (4 x 0.5) = 2750 kg You are required to hang a chain block to lift a load. The chain block will be supported from an inverted snatch block on a span rope fixed between two beams? The span between the beams is 20 metres. (C) The weight of the load is 1250kg. The weight of the lifting gear and load hauling part is 85kg. Calculate the tension in the span rope when the sag is at its recommended minimum. - Answer: ( (1250 + 85) x 20)/(4 x 1) = 6675 kg 'No load' allowable sag of span line - Answer: One twentieth span or 5% span Tension in span rope? - Answer: (Load x Length)/(4 x Sag) What is meant by the term "two blocking"? - Answer: The load block contacts the boom point sheaves. Lifting 20,000 lbs with a 2-leg bridle sling at 30° horizontal sling angle, what is the force applied to each leg? - Answer: 20,000 pounds. In multiple crane lifts using an equalizer beam, the weight of the beam should be considered: - Answer: Part of the load weight What is required if there is a deviation from the lift plan? - Answer: A new lift plan On level ground using skids and rollers, what percent of the weight of the load should yield the required line pull as a general rule of thumb? - Answer: 5% All of the following results of unbalanced reeving of the hook block EXCEPT: - Answer: Wear on the hook Before a spreader bar or beams can be used they MUST have been: - Answer: Tested and approved When materials are being hoisted to an upper level, tag line is used to: - Answer: Help control the lead Two cranes are lifting 100 tons. If crane A has 40% of the load, how much weight will crane B have on its hook? - Answer: 60,000 pounds To CONFIRM the rated capacity of specific sling, consult the manufacturers: - Answer: Sling tag OSHA regulations require hook replacement if the opening exceeds, what percentage of it original throat opening? - Answer: 15% At what percentage of increase in length should a chair sling be removed from service? - Answer: 5% The methodical process that attempts to identify hazards and devise plants to overcome or eliminate hazards which may interfere with crane or rigging is called - Answer: Lift plan Why provides additional control of a load being lifted? - Answer: Tag lines When traveling on a rubber tire mobile crane, how should the boom be positioned? - Answer: In line with the direction of travel Backward stability - Answer: In crane operations, the measure of a crane steadiness in relation to the tipping axis on the opposite side of the crane from the boom. Chicago boom - Answer: A load-hoisting device con-sisting of a single boom attached at its base to either a vertical post or beam in a larger struc-ture, such as a building skeleton, or a freestand-ing pole stabilized by guy wires. Such booms are easily erected and suitable for repetitive hoisting operations at a fixed location. Center of gravity (CG) - Answer: The point where one can assume all of an object's mass, and therefore its weight, is concentrated. The con-cept is useful for determining stability, a load's balance point, and leverage. coefficient of friction (CF) - Answer: A ratio that expresses a comparison between the force nec-essary to move an object over the surface of an-other material, and the pressure between the two materials. Combined CG - Answer: The sum of the crane's and load's CGs at a position along an imaginary line connecting the two CGs Cribbing - Answer: A stack of heavy squared timbers laid in a crisscross pattern to temporarily sup-port loads during movement and placement. Dynamics: - Answer: The response of objects to the ap-plication of forces, moments, or torques. Forward stability - Answer: In crane operations, the measure of the crane's steadiness in relation to the tipping axis on the same side as the boom. Impact loading - Answer: Sudden forces acting on an object due to collisions or other dynamic events Inclined planes - Answer: Flat surfaces placed at a shallow angle that connect levels at different heights. A ramp is an example of an inclined plane. Momentum - Answer: A property of a moving object that is directly proportional to both its mass and speed. Non-centered lift - Answer: Any lift attempted when the hoist line is not vertical or the hook is not directly above the load's center of gravity. Pendulum effect - Answer: Using polar terms to escalate disagreement or argument. "You are always lazy." Rebar: - Answer: Shortened form of the term reinforce-ment bar. Used to identify individual rods, bundles, and field-fabricated meshes of rods that reinforce poured concrete structures.