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CRANES & SLINGS. 29 CFR 1910.179, 184 29 CFR 1926.550. Session Objectives. Understand the basics of crane operations Choose the correct sling or rigging hardware Inspect rigging hardware Rig a load correctly. Cranes Are Everywhere.
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CRANES & SLINGS 29 CFR 1910.179, 184 29 CFR 1926.550
Session Objectives Understand the basics of crane operations Choose the correct sling or rigging hardware Inspect rigging hardware Rig a load correctly
Cranes Are Everywhere • Cranes, derricks, and jib hoists are used in almost every industrial setting • Cranes can be found on most construction sites
Types of Cranes • Mobile • Telescopic • Tower • Gantry/Overhead • Vessel
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 • Who can give the hand signals? or Who can be a signaler? • a person qualified to give crane signals to the operator, • there should be only one designated signaler at a time, • if signalers are changing between each other, the one in charge should wear a clearly visible badge of authority, • a crane operator should move loads only on signals from one signaler, • a crane operator must obey STOP signals no matter who gives it.
Hand Signals • What should you do when in charge of signaling? • The signaler must: • be in clear view of the crane operator, • have a clear view of the load and the equipment, • keep persons outside the crane's operating area, • never direct a load over a person.
1926.550(a)(4)Hand signals to crane and derrick operators shall be those prescribed by the applicable ANSI standard for the type of crane in use. An illustration of the signals shall be posted at the job site.
Sling Selection • Rated capacity • Material composition • Size, design, and configuration • Condition • Tags
Sling Types • Eye to eye versus endless • Steel chains • Wire rope or steel cable • Metal mesh • Fiber rope (natural or synthetic) • Synthetic mesh
Chain Slings • Strong • Fit shape of load • Tolerate high temperatures • Damaged by shocks • Watch for damage
Wire Rope Slings • Composed of strands of wire rope • May have fiber core • Can experience cracking or kinking
Rope Lay • Right lay • Left lay
Rope Lay (cont.) • Regular lay • Lang lay
Wire Rope Sling Selection • Strength • Flexibility • Durability
Wire or Metal Mesh Slings • Similar to chain mail • Fits shape of load • For basket or choke hitches
Fiber Rope Slings • For lighter loads • Protect surface of load • Susceptible to deterioration • Stretch when wet • Must be inspected thoroughly
Synthetic Web Slings • Nylon, Dacron, or polyester • Contour to fit the load • Durable and resistant to degradation
Which Sling Is It?Match the sling name to the description Chain Wire Rope Metal Mesh Fiber Rope Synthetic Web Lay is important For heavy or hot loads For light loads only Unlikely to biodegrade Similar to chain mail
Questions? • Basic crane operations • Rated capacity and load charts • Slings and sling selection
Sling Inspection • Check for: Excessive wear Distortion or stretching Corrosion Heat stress Chemical damage • Check for: Excessive wear Distortion or stretching Corrosion Heat stress Chemical damage
Chain Sling Inspection • Check inside ends and outside edges • Excessive stretching is unsafe • Watch for binding
Wire Rope Sling Inspection • Cracking and pitting • Kinking • Deformation • Rust • Heat stress • Broken wires • Damaged fittings
Fiber Rope Sling Inspection • Dry, discolored fibers • Powder or dust from internal wear • Fibers that come apart
Synthetic Web Sling Inspection • Holes, snags, tears • Broken or worn stitching • Heat stress and burns
Sling Maintenance • Keep it clean • Repair may be possible • Lubricate wire rope slings • Store safely
Shackles, Clips, Eyes, and Other Hardware • Inspect with care • Never use equipment with parts malfunctioning or missing
Hooks • A safety latch is essential • Bent hooks must be retired
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.
Hitches • Single vertical • Bridal hitch • Basket hitch • Choker hitch Learn with experience!
Sling Angles • Ratings based on a vertical hang • Slings hung >= 5° angle from vertical • Slings used at angles should be checked for capacity
1,000 lb. 1,000 lb. Angle Examples • 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
The“Nevers” Never • Use a twisted line • Lift by the block hook • Use unsafe equipment • Allow an unsafe lift
Use more than one signalman Work under a suspended load Turn your back on a lift The“Nevers”(cont.) Never
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