Nylon Web and Endless Round Slings and Shackles
This information is based on the following regulations and Standards
• OSHA 29 CFR
• MMS CFR
• API SPEC (A
• ANSI/AMSE B 30.9
• Wire Rope Technical Board (Wire Rope Users Manual)
NOTE: Abrasions, Bending, and Crushing represent the ABC’s of wire rope abuse. The primary goal of a good inspection practice is to discover such conditions to maintain that the wire rope remains in service. When any sudden degradation indicates a loss of the original rope strength, a decision must be made quickly.
Qualified Inspector
The decision of to replace or retain wire rope in service must be made by a qualified and experienced inspector.
Two basic questions that need to be answered by the inspector at the time of the inspection prior to use are:
1. Does the rope’s condition present any possibility of failure?
2. Is the rate of deterioration such that the wire rope will be safe to use until the next scheduled inspection?
In order for an inspector to do this, he must:
a. Understand the details of the equipment’s operation
b. Prior knowledge of the frequency of inspection
c. Maintenance history
d. Consequence of failure
e. Historical knowledge of similar equipment
Common Causes of Nylon / Synthetic Webbing Damage
Effects of the Environment
• Ultra violet damage
• Caustic / Acid damage
Damage due to misuse
• Used on sharp corners
• Exposed at excessive temperatures
• Expose to welding
• Abrasions
• Tag information is illegible or missing
• Damage due to overloading
Inspection Criteria for Nylon / Synthetic Webbing
• Heat damage
• Ultra violet damage
• Tag readable
• Caustic damage
• Tears, snags, puncture holes, and cuts
• Damaged end fittings
• Worn / broken stitching
• Knots
• Severe abrasions
Inspection and Replacement
(ANSI B30.9)
All slings shall be visually inspected by the person handling the sling each day they are used. In addition, a periodic inspection shall be performed by a designated person annually, and shall include a record of the inspection.
Shackle Removal Criteria
Inspection and Removal Criteria
Note: Written records are not required on shackles
• Deformation stretch or distortion
• Gouges, cracks, and nicks
• Excessive corrosion or pitting
• Heat damage including weld spatter or arc strikes
• Wear in excess of 10% from original catalogue dimensions at any point around the body
• Incomplete pin engagement
• Proper working load permanently marked for visual
• Shackle body permanently marked by manufacturer
• Raised and stamped letters on side of bow (manufacturer name (logo), size, rating
• Pins will match shackle (no substitute except for ROV friendly models)
• No welding or changes in the original manufacturer’s design of the shackle
Most Common Causes of Damage to shackles
• Effects of the Environment
-Excessive corrosion due to exposure
• Damages due to misuse
-Overloading shackle
-Side pull to shackle
-Gouges and nicks
-Heat damage exposure to welding or other heat sources
-Excessive ear to load bearing contact points
Conclusion:
A qualified rigger is one who has the training, knowledge, and resources to inspect all rigging gear. The ultimate goal is to insure that the rigging gear is safe for the lift and the rigger truly understands the causes for a variety of rigging component failures. It is his responsibility to use "Stop Work Authority" when he / she determine a lift is UNSAFE.
Remember: When in doubt, throw it out!
Special thanks to Morgan City Rentals (Morgan City, LA) for supplying the content for both "Guidelines to a Good Inspection Practice: Parts 1 and 2"
