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Cranes and Slings 29 CFR 1910.179 and 184. Cranes Are Everywhere. Cranes, derricks, and jib hoists are used in almost every industrial setting Cranes can be found on most construction sites. Crane and Sling Goals. Crane hazards, inspection, and operations Sling inspection and use Quiz.
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Cranes Are Everywhere • Cranes, derricks, and jib hoists are used in almost every industrial setting • Cranes can be found on most construction sites
Crane and Sling Goals • Crane hazards, inspection, and operations • Sling inspection and use • Quiz
Crane Hazards • Crane, sling, or hook could fail if overloaded • Load could flip, turn, or release suddenly if not attached correctly • People or objects could be struck by the load
Crane Capacity • Rated capacity clearly marked on each side of the crane • If more than one hoisting unit, each hoist must be marked with rated capacity • Markings clearly legible from the ground
Crane Inspections • Daily inspections include: • Operating mechanisms to ensure proper working order • Air or hydraulic systems for leaks • Hoist chains/ropes for wear, twisting, distortion • Periodic inspections: • Deformed, cracked, or corroded components • Loose bolts or rivets • Wear on brakes, chain drive sprocket
General Operating Rules • Only trained, designated operators are permitted to operate cranes • A crane must not be loaded beyond its rated capacity • Follow all safe operating procedures
Attaching the Load • Hoist chain/rope free of kinks or twists • Do not wrap hoist chain/rope around the load • Attach the load to the load block hook with slings or other approved devices
Hooks • Safety latch or clip • Load in center of hook’s curve • Picking up load with the hook’s tip causesit to open up and weaken • Replace hooks that are bent open or twisted
Moving the Load • Be sure the hook and hoist are directly over the load • Ensure that chains/ropes/slings are not twisted • Ensure that the load is well secured and balanced • When traveling, keep the load close to the floor
Hoisting Safety • Avoid sudden acceleration or deceleration • Watch for obstructions • Never leave controls with load suspended • Do not use cranes for side pulls • Never lower the load below the point where less than two full wraps of rope remain on the hoisting drum
Hoisting and People • Never carry loads over people • Do not hoist, lower, or travel a load when an employee is on the load or hook • When two or more cranes are lifting a load, put one qualified person in charge
Hand Signals • Hoist up • Hoist down • Stop • Travel
Crane and Sling Goals • Crane hazards, inspection, and operations • Sling inspection and use • Quiz
Sling Types • Eye to eye versus endless • Steel chains • Wire rope or steel cable • Metal mesh • Fiber rope (natural or synthetic) • Synthetic mesh
Operator Sling Inspections • Each day before use by a trained operator • Check slings and attachments for damage • Immediately remove damaged and defective slings from service
Thorough Sling Inspections • At least annually, recorded in a log • Chains • Wire rope • Metal mesh • Fiber rope • Synthetic web
Sling Rules • Never load beyond rated capacity • Label properly • Never shorten with knots, bolts, or any other device • Protect from sharp edges • Attach securely to the load
Sling Rules (cont.) • Protect hands and fingers • Use care when pulling a sling • Never drag a sling • Do not use a damaged or defective sling
Sling Storage • Hang slings on a wall • Never leave on the ground • Never expose to water, welding sparks, chemicals, etc.
Sling Hitches • Vertical • Choker • Basket
Sling Angles • Ratings based on a vertical hang • Slings hung >= 5° angle from vertical • Slings used at angles should be checked for capacity
Angle Examples 1,000 lb. 1,000 lb. • Assume 1,000 lb. load lifted with 2 slings • Slings vertical: 500 lb. each • Slings 45° from vertical: 707 lb. each • Slings 60° from vertical: 1,000 lb. each • Slings 75° from vertical: 1,930 lb. each
Crane and Sling Goals • Crane hazards, inspection, and operations • Sling inspection and use • Quiz
Summary • Only trained and authorized operators allowed to use a crane • Inspect both crane and slings before use • Properly secure the load and try to keep slings vertical • Keep all people away from a load while it is being hoisted or moved
Quiz 1. When do slings need to be inspected? __________ 2. Wrapping the hoist’s chain/rope around the load is a safe way to hitch a load. True or False 3. Name two things on a crane that need to be inspected each day: ___________and ___________. 4. What prevents a hook from becoming disconnected from the load? _____________________________ 5. Each crane must be clearly marked with its rated capacity. True or False
Quiz (cont.) 6. Lift load high when traveling in order to avoid people or objects. True or False 7. The best way to shorten a chain sling is with a strong bolt through two links. True or False 8. When using a basket hitch, the load must be properly balanced. True or False 9. What causes slings to be subjected to loads in addition to the weight of the object? __________ 10. What should be attached to every sling? __________
Quiz Answers 1. Inspect slings each day before they are used. 2. False. Never wrap the hoist’s chain/rope around the load. 3. Daily crane inspections include operating mechanisms, air/hydraulics, hoist chains/ropes. 4. A safety latch or clip prevents the hook from disconnecting from the load. 5. True. Cranes must be clearly marked with their rated capacity.
Quiz Answers (cont.) 6. False. Travel with the load as near to the ground as possible. 7. False. Never shorten a sling with a bolt or a knot. 8. True. A basket hitch requires a balanced load. 9. Hanging slings at angles causes them to be subjected to horizontal forces. 10. A label with the sling’s rated capacity.