signalman and rigger

mobile crane hand signals

signalman is part of the crane crew and is responsible to the operator to give signals for lifting, swinging, and lowering loads. A signalman should be a qualified seasoned crane operator. Not only does the signalman give signals for handling loads but the signalman can visually observe what the operator cannot see from the operator’s cab. For example, during a lift the signalman should make a visual check of the following: 1. The load hook is centered over the center of balance of the load, as the weight is being lifted by the crane. 2. The boom deflection does not exceed the safe load radius. 3. All the rigging gear is straight and not causing damage to itself or the load. 4. During a lift with a lattice boom crane, check the boom suspension system and boom hoist reeving to ensure proper operation. 5. Check the hook block and boom tip sheaves reeving to ensure proper operation. 6. Check the stability of the outriggers especially when swinging from one quadrant of operation to another. NOTE: On some cranes, the capacity of the crane changes when swinging from the rear quadrant to over-the-side quadrant. 7. Use tag lines and tag line handlers to prevent the load from swinging or twisting.

Riggers have many responsibilities. They decide which pulleys, booms, braces, and cables are strong enough for each job. They also must know where to attach the hooks, chains, and cables to lift a load safely. In some cases, riggers build equipment around the object to be moved, such as a tower or boom. While the object is being lifted, riggers use hand signals and other means to direct crane operators and help guide the objects into place.

Riggers help operate machines that move heavy objects including steel plates, bundles of steel rods, drilling towers, platforms, and the heavy construction equipment used to build and take down steel structures.

Riggers have many responsibilities. They decide which pulleys, booms, braces, and cables are strong enough for each job. They also must know where to attach the hooks, chains, and cables to lift a load safely. In some cases, riggers build equipment around the object to be moved, such as a tower or boom. While the object is being lifted, riggers use hand signals and other means to direct crane operators and help guide the objects into place.