FAQ

A. Twin-Path® Heavy Lift Slings

1. Can a Twin-Path sling be used in a fitting or trunnion which is less than the sling's width?

Yes, a Twin-Path® sling can fit into spaces half its catalog width with no reduction in capacity. The Twin-Path section of the catalog lists two dimensions under Nominal Body Width. The larger dimension is the flat tube measurement before installing the core yarn. The smaller dimension is the approximate reduction in width you can expect to achieve when placing the sling in a smaller fitting. The paths of the Twin-Path sling should be squeezed together to reduce the dimension – DO NOT fold one path over the other to create a reduced dimension. More info… Twin-Path® Care and Use Guide

2. What is the Check-Fast® inspection system?

The Check-Fast® inspection system with External Warning Indicator (EWI) provides a pass/ fail inspection of the internal load bearing core yarn. Damage to the core yarn from ultraviolet (UV) light degradation, fiber on fiber abrasion, fatigue, or severe overload can be detected. If the sling is mistakenly overloaded beyond rated capacity, the EWI is designed to disappear before the sling fails. The sling inspector now has a GO/NO-GO inspection device rather than relying on a subjective hand-over-hand inspection to make an educated guess if the load bearing core yarns are in good condition. If the EWI is not visible, remove the sling from service and send to the manufacturer for repair evaluation. This safety system is available for High Performance K-Spec® Fiber Roundslings or polyester roundslings fabricated by authorized Slingmax® dealers. More info... Check-Fast® Explanation Video

3. What is the difference between the Check-Fast inspection system and Tell-Tails?

Tell-Tails are extensions of the core yarn bundles and are designed to function as overload indicators. The tails are designed to retract and eventually disappear if the sling is overloaded. Tell-Tails should extend past the tag area of each sling. If both Tell-Tails are not visible remove the sling from service and send to the manufacturer for repair evaluation. This inspection system also combines use of a fiber optic cable. The condition of the internal load bearing core yarn can be inspected by checking the continuity of the fiber optic cable. If crushing, cutting, heat or chemical damage has occurred then the damage to the fiber optic cable will destroy its ability to transmit light from one end to the other, giving the inspector a reason to remove the sling from service and send it in for repair evaluation. Though not required, the fiber optic inspection system is also an option with the Check-Fast® system.

4. What pin diameter or hardware diameter is OK with a Twin-Path Sling?

The Slingmax® statement on hardware is in the ‘Mechanical Considerations’ section of our catalog. Item #7 states “Slings used with fittings shall be compatible with the fittings used. The lifting capacity shall be rated at the lower of the sling or fitting. Fitting openings shall be of the proper shape and size to assure that the sling will seat properly”. In other words, the diameters of most commercially available hardware are sufficient for use with a Twin-Path sling of equal capacity. Twin-Path® Minimum Hardware Diameter Charts: Imperial / Metric

5. What happens if oil or gasoline gets on my Twin-Path Sling?

Hydrocarbons and oils do not affect the performance of any Twin-Path® sling. Please reference the chart for Chemical Resistance of K-Spec® core yarn for additional information. Twin-Path slings with Covermax® jackets may be cleaned using a commercially available mild detergent and ambient temperature water, then allowed to air dry.

6. Do Twin-Path slings stretch? I’ve seen loads bounce with synthetic slings.

At rated capacity, nylon slings will stretch up to 15%. Round slings made with Polyester core yarn will stretch 3%. Braided Polyester slings will stretch 9%. Twin-Path slings with K-Spec® core yarn stretch less than 1% at rated capacity, about the same as wire rope slings.

7. What are the length tolerances on Twin-Path slings?

Our advertised length tolerances are listed in Technical Bulletin #4, however, much tighter and more precise tolerances are readily achieved. Remember that pull-to-pull measurements of Twin-Path slings should be measured under a light load, even if it is only at 10% of Vertical Rated Capacity (VRC). While the K-Spec® core yarns will not stretch nor shrink, the Covermax® jacket is a bulked nylon which will show some expansion and contraction over time.

8. If a synthetic roundsling has one interior core yarn which has been damaged or cut, can it still be used if the sling’s capacity is de-rated?

NO! Roundslings that suffer damage to the load bearing fibers must be removed from service. These slings shall be destroyed to prevent inadvertent use.

9. If the cover on a Twin-Path sling is damaged can it be repaired?

Yes. The Covermax cover is actually comprised of two covers – a green outer cover and a red inner cover. As long as there is no damage to the core yarns, the cover may be safely repaired. With the Twin-Path® design, our manufacturers can repair the cover without the risk of sewing over the internal core yarns during repair.

10. Are all Twin-Path slings proof tested before reaching the customer?

Yes. As part of our manufacturing process each Twin-Path sling is proof tested to two times its vertical rated capacity. In addition, every repaired Twin-Path sling is also proof tested before it is returned to the customer.

11. Can I overlap Twin-Path slings in a shackle or other hardware?

Yes. The paths should be laid directly on top of each other to prevent possible tearing of the Covermax® jacket. Twin-Path® Care and Use Guide

B. Sling Protection

1. What is the difference between abrasion protection and cut protection?

Abrasion protection is needed when the sling is wrapped around a load which is rough, dirty or gritty. Slingmax® abrasion protection products include Synthetic Armor™ (Synarm) Pads and shackle pin pads. Cut protection is needed when there is an edge or corner that the sling may come in contact with. Slingmax® cut protection devices include the CornerMax® pad and CornerMax® sleeves, engineered devices designed to provide cut protection up to 25,000 lbs. per inch of sling width. Technical Bulletin 23

2. Can I use a Synthetic Armor Pad for cut protection?

No. Synthetic Armor Pads are intended for abrasion protection or to increase the diameter of a bearing surface. If cut protection is required, we recommend the use of the CornerMax® products.

3. How do I know if a load edge is 'sharp' enough to require a CornerMax Pad?

The word “sharp” is considered subjective and is no longer used in our catalog or website. CornerMax Pads should be utilized to protect the sling from all edges and corners.

C. Wire Rope Slings

1. Why use a multi-part wire rope sling instead of a single-strand wire rope sling?

A single strand sling is less flexible than a multi-part wire rope sling. Also, a multi-part wire rope sling provides a better D/d ratio.

2. Are the D/d ratios for the Slingmax® wire rope slings based on component diameter?

No. The D/d ratios are based on the finished diameter. Finished and component diameters for each wire rope sling may be found on the respective catalog page for each item.

3. What are the reductions for the Slingmax wire rope slings if you are not able to use the correct D/d?

Approximate reductions for the sling body are as follows:
  • 5:1 | 100%
  • 4:1 | 92%
  • 3:1 | 84%
  • 2:1 | 73%
  • 1:1 | 65%
  • Less than 1 | 50%

4. What is the difference between a Gator-Max® and a Gator-Laid® sling?

Gator-Max® is hand-spliced, Gator-Laid® is made using swaged sleeves.