Note: | An external code mark on the sling is an acceptable means of recording the inspection as long as the code can be traced back to a record. |
Inspect synthetic rope slings for the following conditions: | Perform inspections: | |||
• | Missing or illegible sling identification; | |||
• | Cuts, gouges, or areas of extensive fiber breakage along the length; | |||
• | Abraded areas on the rope; | • | At least once a year for slings in normal service; | |
• | Damage that is estimated to have reduced the effective diameter of the rope by more than 10%; | • | At least once a quarter for slings in severe service; | |
• | Uniform fiber breakage along the major part of the length of the rope in the sling such that the entire rope appears covered with fuzz or whiskers; | • | As recommended by a qualified person for slings in special service. | |
• | Inside the rope, fiber breakage, fused or melted fiber (observed by prying or twisting to open the strands) involving damage estimated at 10% of the fiber in any strand or the rope as a whole; | |||
• | Discoloration, brittle fibers, and hard or stiff areas that may indicate chemical, ultraviolet or heat damage; | |||
• | Dirt and grit in the interior of the rope structure that is deemed excessive; | |||
• | Foreign matter that has permeated the rope, making it difficult to handle and attracting and holding grit; | |||
• | Kinks or distortion in the rope structure, particularly if caused by forcibly pulling on loops (known as hockles); | |||
• | Melted, hard, or charred areas that affect more than 10% of the diameter of the rope or affect several adjacent strands along the length that affect more than 10% of strand diameters; | |||
• | Poor condition of thimbles or other components manifested by corrosion, cracks, distortion, sharp edges, or localized wear; | |||
• | Hooks that have any of the following conditions: | |||
– | Any visibly apparent bend or twist from the plane of the unbent hook; | |||
– | Any distortion causing an increase in throat opening 5%, not to exceed one-quarter inch, or as recommended by the manufacturer; | |||
– | Wear exceeding 10%, of the original section dimension of the hook or its load pin, or as recommended by the manufacturer; | |||
– | Self-locking mechanism that does not lock. | |||
• | Other visible damage that raises doubt about the safety of the sling. |
Type of equipment: | Proof load test: | |
• | Single leg slings; | To a minimum of two times the single leg vertical hitch rated load. |
• | Multiple leg slings; | |
• | Endless slings; | |
• | Fittings attached to single legs. | |
Master links for two-leg bridle slings. | To a minimum of 4 times the single leg vertical hitch rated load. | |
Master links for 3-leg bridle slings. | To a minimum of 6 times the single leg vertical hitch rated load. | |
Master links for 4-leg bridle slings. | To a minimum of 8 times the single leg vertical hitch rated load. |
Note: | Rated loads are based on the following factors: |
• Strength of the sling material; | |
• Design factor; | |
• Type of hitch (see Figure 24, Hitch Types for Synthetic Rope Slings); | |
• Angle of loading (see Figure 18, Angle of Loading); | |
• Diameter of curvature over which the sling is used (see Figure 19, D/d Ratio). |
Figure 24 Hitch Types for Synthetic Rope Slings |
The symbols below represent load or support in contact with the rope sling. The contact surface diameter divided by the rope diameter is designated D/d ratio as described in Figure 19. | |
Represents a contact surface which must have a diameter of curvature at least double the diameter of the rope from which the sling is made. | |
Represents a contact surface which must have a diameter of curvature at least 8 times the diameter of the rope. | |
Represents a load in choker hitch and illustrates the rotary force on the load and/or the slippage of the rope in contact with the load. Diameter of curvature of load surface must be at least double the diameter of the rope. |
Note: | Legs 5 degrees or less from vertical may be considered vertical. For slings more than 5 degrees vertical, the actual angle must be used. |