Wire Rope Lifting Slings and Assemblies
Wire rope lifting slings, bridles and assemblies provide great durability and high tensile strength for lifting heavy loads. In addition, wire rope lifting slings are lighter in weight and more cost efficient than chain slings. Wire rope slings, sometimes referred to as wire slings, or cable lifting slings, are constructed using a variety of different styles and sizes of steel wire rope. Every style and size of wire rope offers different properties and benefits such as:
- Rotation Resistance
- Abrasion Resistance
- Bending Fatigue Resistance, etc.
Each type of wire rope has benefits and drawbacks. What all wire ropes have in common however, is that they are made up of steel wires which form individual stands. These strands are laid in a helical pattern around a fiber or steel IWRC (independent wire rope core) core.
Wire rope lifting slings, bridles and assemblies are highly customizable, so if you are unable to find what you are looking for, or if you don’t know exactly what you need, call or email our sales team to speak with a rigging product specialist.
Wire Rope Sling Applications and Configurations
Wire rope lifting slings are the most popular type of sling used in material handling. They are especially popular in the following industries:
- Oil and Gas
- General Manufacturing
The durability of steel cable lifting slings is also put to the test in the harsh environments seen in steel mills and forging facilities. Every steel wire rope configuration will offer different properties and will be better equipped to handle certain applications. Generally, a smaller number of large outer wires will provide more wear, corrosion and abrasion resistance. Conversely, a larger number of smaller outer wires will provide better flexibility and fatigue resistance.
After you decide what construction and size of wire rope fits your application, you must configure the entire sling. Wire rope bridles and assemblies are available in single-leg, double-leg, triple-leg, and quadruple-leg configurations. They most commonly have 2 eyes and are constructed using a mechanical flemish splice. Wire rope lifting slings can be used in vertical, choker and basket hitches. They can also be equipped with a variety of attachments and fittings to accommodate almost any overhead lifting application.
Wire Rope Sling Advantages
- Lighter in weight and more cost efficient than alloy chain slings
- Smaller diameter design than other sling types, with high strength and flexibility
- Braided or multi-part slings:
- Offer higher resistance to kinking than single-part slings
- Offer high flexibility
- In a choker hitch the wire rope is tight and secure around the load
- Quickly regain their original shape after a lift
- The hardware (master links and hooks) can be re-used if the wire rope is damaged enough to be taken out of service
Wire Rope Sling Disadvantages
- Lower strength to weight ratio than other sling types
- Wire ropes can be difficult to inspect, specifically in and around the fiber or IWRC core
- Kinking, abrasion, and cutting can result from misuse and abuse
- Although wire rope sling fittings and attachment can be reused, the wire rope itself is not repairable. If a wire rope sling fails an inspection, it is to be properly destroyed and disposed of
- Wire rope is prone to not only external but also internal corrosion
- Compromises must be made when choosing a wire rope design: a rope that is more fatigue resistant will be less abrasion resistant — and vice versa
- Wire rope lifting slings are never to be used at temperatures above 400°F or below -40°F
Wire Rope Sling Inspection
It is important to inspect wire rope slings regularly and to keep a record of all sling inspections. At Tri-State Rigging Equipment we offer a full range of rigging inspection and repair services. The standards that govern wire rope sling inspection are OSHA 1910.184 and ASME B30.9. It is recommended that wire rope rigging slings first undergo an initial inspection when you receive the lifting sling from the manufacturer. The purpose of this initial inspection is to:
- Check sling tag for correct capacity
- Check the length of the sling
- Make sure the sling has the correct design and construction of wire rope
- Make sure the lifting sling meets any other lifting specs or requirements you may have
Wire rope slings, bridles and assemblies should also be inspected by a designated and qualified individual every day before use to make sure that the sling is in working condition and will lift its rated capacity. The person performing the inspection should examine all the wire rope, fastenings and attachments on the wire rope sling. The inspector is looking for visual indications of any defects, deformities and general damage that might affect the integrity of the sling.
Depending on your application, it may be recommended that you perform these visual inspections more than once a day. If the wire rope sling is used many times throughout the day, by multiple individuals, across multiple shifts, it is imperative that the sling be inspected before every shift change and before any change in lifting application.
ASME standards further require a thorough periodic inspection to be performed at least once a year by either a professional service provider, or by a Qualified Person. In addition, written records must be kept until the next periodic inspection. The rejection criteria for periodic wire rope sling inspections are as follows:
- Missing or illegible sling identification
- 10 or more randomly distributed broken wires in one rope lay, or 5 or more broken wires in one strand in one rope lay, for strand-laid grommets and single part slings.
- Wires and strands out of place
- Heat Damage: Any fused wires, weld spatter, metallic discoloration, or loss of core lubricant
- Damaged end attachments
- Bent Hooks
- Corrosion (excluding light surface rust)
- Slipped or pulled eye splices
- Unbalance caused by kinks
- For 2, 3, or 4-leg slings and cable-laid grommets, use the table below:
|Allowable Broken Wires Per Lay or One Braid
|Allowable Strands Per Sling
|Less than 8 Part Braid
|8 Part or Greater Braid
If your wire rope sling shows any of the rejection criteria above, you must remove the sling from service, and it must be destroyed. Properly destroying rigging equipment is imperative because you can be held accountable for damage done by people who find and use your discarded slings. Therefore, lifting slings deemed not suitable for service must be destroyed beyond use and beyond repair. The process for destroying a wire rope sling is as follows:
- Cut sling into 3’ or 4’ sections
- Cut the eyes of the wire rope using a torch or chop saw
- Cut the wire into smaller pieces if it is still possible to form an eye using the segments
- Remove any tags or labels
The purpose of daily and periodic wire rope sling inspections is not to get anyone in trouble but rather to gain knowledge of the frequency of use, severity of conditions, and nature of lifts, and consider how all these factors affect your wire rope sling. The most important reason to perform daily and periodic wire rope sling inspections, however, is to keep you and your coworkers safe.
Tri-State Rigging Equipment is a custom manufacturer, service provider and distributor for all wire rope lifting slings serving clients from coast to coast, Canada, Mexico and especially focused in the states of Missouri, Illinois, Indiana, Iowa, Kansas, Nebraska, Arkansas, Mississippi, Tennessee, Kentucky, South Carolina, Florida, and Oklahoma.