Rigging facts you should know


BASKET = 200%         STRONGEST


CHOKER = 50%

 Do the following when rigging a load:

  • Determine the weight of the load. Do not guess.
  • Determine the proper size for slings and components.
  • Do not use manila rope for rigging.
  • Make sure that shackle pins and shouldered eye bolts are installed in accordance with the manufacturer’s recommendations.
  • Make sure that ordinary (shoulder less) eye bolts are threaded in at least 5 times the bolt diameter.
  • Use safety hoist rings (swivel eyes) as a preferred substitute for eye bolts wherever possible.
  • Pad sharp edges to protect slings. Remember that machinery foundations or angle-iron edges may not feel sharp to the touch but could cut into rigging when under several tons of load. Wood, tire rubber, or other pliable materials may be suitable for padding.
  • Do not use slings, eye bolts, shackles, or hooks that have been cut, welded, or brazed.
  • Install wire-rope clips with the base only on the live end and the U-bolt only on the dead end. Follow the manufacturer’s recommendations for the spacing for each specific wire size.
  • Determine the center of gravity and balance the load before moving it.
  • Initially lift the load only a few inches to test the rigging and balance.
  • The object (a shackle, a crane hook, a steel bar, etc.) you place into the sling eye must not be larger than 1/2 of the sling eye length.


General Rigging Safety Requirements

  • Only select rigging equipment that is in good condition.
  • All rigging equipment shall be inspected annually; defective equipment is to be removed from service and destroyed to prevent inadvertent reuse.
  • The load capacity limits shall be stamped or affixed to all rigging components.
  • A minimum safety factor of 5 to be maintained for wire rope slings.


 WIRE ROPE                                        


A competent person must begin a visual inspection prior to each shift the equipment is used, which must be completed before or during that shift. The inspection must consist of observation of wire ropes (running and standing) that are likely to be in use during the shift for apparent deficiencies, including those listed in paragraph (a)(2) of this section. Untwisting (opening) of wire rope or booming down is not required as part of this inspection.


In running wire ropes: Six randomly distributed broken wires in one rope lay or three broken wires in one strand in one rope lay, where a rope lay is the length along the rope in which one strand makes a complete revolution around the rope.


In rotation resistant ropes: Two randomly distributed broken wires in six rope diameters or four randomly distributed broken wires in 30 rope diameters.


In pendants or standing wire ropes: More than two broken wires in one rope lay located in rope beyond end connections and/or more than one broken wire in a rope lay located at an end connection.


A diameter reduction of more than 5% from nominal diameter.