What is D/d Ratio & Why is this Critical for Lifting Slings?

What effect does D/d Ratio have on lifting slings and their sling capacities?

You may wonder what D/d ratio is and what purpose it serves when lifting loads with different types of slings. After all, it can be confusing as there are multiple factors you have to take under consideration such as knowing the weight of the load, the sling’s working load limit (WLL), and the load’s center of gravity.

Identifying the D/d ratio when using any type of sling for a lift is critical. If the lifting sling tightly bends over too much during the lift – the sling will get damaged itself. This then leads to unsafe rigging practices, thus making it difficult to repair and creating high replacement costs.  

To have a safe lifting operation, read about D/d Ratio and the slings we carry at US Cargo Control.

What is D/d Ratio?

In a short sentence, it describes the load size versus the size of the sling placed on the load.

The term D/d ratio works as a simple mathematical equation where you’re learning the diameter or distance of the load you’re picking up. The upper case “D” refers to the ratio of the diameter around the object which the sling is bent, and the lower case “d” represents the diameter of the sling being used.

The Formula for D/d Ratio:

The diameter of the load divided by the diameter of the sling = D/d Ratio

Unirope's definition of D/d ratio
Photo Courtesy of Unirope

For example, you’re picking up an object that’s 12 inches in diameter and you use a 3/8″ chain to pick it up. This is 12″ divided by 3/8″ = 32, which 32 is the D/d Ratio. If the diameter is 10″ and the diameter of the rope is 1/2, the D/d Ratio is 20.

Why is D/d Ratio Important?

The D/d Ratio has a tremendous impact on sling capacity when using slings like wire rope, chain, polyester round slings, and nylon slings. It can determine the sling’s efficiency or capacity reduction, and allow you to make corrections before continuing the lift. If you see a tight bending of the sling, this means there’s a smaller than recommended D/d Ratio.

Using a smaller D/d Ratio that’s not recommended for your lift can aggravate the bending motion. This can result in fatigue, irregular wear, and increased deterioration. Once this occurs, you’d have to perform frequent inspections and go through costly wire rope replacements.

Each sling type has different strength efficiencies, which is why we included a table below that describes the efficiency of various sling constructions with standard D/d Ratios:

Mechanically spliced, single-part slings25 times rope diameter
Hand-Spliced, single-part slings15 times rope diameter
Braided multi-part slings of 6 parts25 times component rope diameter
Braided multi-part slings of 8 parts25 times component rope diameter
Helically laid multi-part slings25 times component rope diameter
Hand-tucked grommets and mechanically joined grommet5 times sling body diameter
Union Rope’s Rated Capacity, Design Factors, and D/d Ratios

What Will Sling Damage Look Like?

wire rope damage

When a sling is tightly bending around another object, there is a loss of sling capacity. As D/d Ratio decreases, this capacity loss becomes greater and the sling will become less efficient. There is a direct correlation between D/d Ratio and the efficiency of the sling (or rated capacity).

Not only is it important to understand the D/d Ratio of the lifting sling, but it’s also equally important that fittings and rigging hardware used in connection points are adequately strong and spatially correct. For instance, if smaller, alloy shackles are used, the webbing edges can get damaged and sling efficiency is lowered due to the bunching of the webbing.

When not used correctly, this could result in bunching, and being crammed into a space will reduce sling efficiency and capacity. Basically, putting too many slings in an undersized shackle or another fitting can result in lost strength.

To understand what slings or fittings should you use for your job, give our team a call at 800-404-7068, and we’ll be glad to assist you.

Different Type of Slings

Now that you have an idea of what D/d Ratio means, continue reading on what lifting slings you should use that’s worth the investment for your lifting situations.

nylon lifting slings

Nylon Slings

Known as synthetic web slings or nylon web slings, our nylon lifting straps perform well for lifting breakable, delicate objects. Its heavy-duty synthetic material has great stretch and flexibility that help the slings mold to the shape of the load. Not only that, the nylon lifting sling’s material is treated to improve abrasion resistance and reduce wear, even in the most rigorous lifting applications.

Chain Slings

If you’re depending on a sling that requires extra strength and durability, the chain sling is your best choice. The chain lifting sling is the strongest and most durable type of sling and is highly popular to use for heavy lifting operations. They will perform better than polyester round slings or nylon slings because they’re more durable, tolerant to hot temperatures, and cut-resistant.

chain lifting sling
Polyester round sling

Polyester Slings

Manufactured in the USA from a continuous loop of polyester yarn that creates exceptional strength, the round slings are versatile, pliable, convenient, and cost-effective. Because of their many benefits, you can use these in vertical, choker, or basket hitches, making them effective to lift a wide variety of cargo!

Wire Rope Slings

Known as steel cable or wire sling, these are more durable than synthetic slings and more cost-effective than chain slings. Wire rope slings are an excellent choice not only for lifting, but also for hoisting, towing, or anchoring loads. Its fabrication offers abrasion-resistance and heat-resistance, as they are made by weaving individual strands or wire around a core.

Wire rope sling

To understand what lifting slings you should use for any lifting operation, read 3 Factors to Consider When Choosing Lifting Slings.

Tackle the Toughest Lifting Jobs with High-Quality Rigging Hardware

We know the importance of quality when it comes to rigging supplies. We carry a variety of rigging hardware, as well as lifting beams and spreader bars that can lift heavy loads safely and efficiently.

Need a custom lifting sling? We can do that! We can customize a lifting sling to meet your specific needs.

Contact our sales team today at 866-444-9990. Our team of product experts is here to answer any questions about rigging hardware, lifting slings, and more.

What is Wire Rope, and How is it Different from Cable Rope?

Read what is wire rope, what are important specifications to look for, and how it’s different from cable rope.

Did you know wire ropes were used as far back as the 1830s for mining hoist applications? Nowadays, we can use steel ropes for many different applications such as lifting and hoisting in elevators and cranes, and for mechanical power transmission. US Cargo Control’s wire rope slings are an excellent choice for heavy-duty jobs as their fabrication offers excellent abrasion resistance and heat resistance for extreme conditions.

Although these slings are beneficial for the lifting and rigging industry, there are a few specifications to know before purchasing them. Continue reading what is wire rope, what are important specifications to look for, and how it’s different from cable rope.

What is Wire Rope?

Up close shot of wire rope sling on shackle
Photo Courtesy: Adobe Stock

These slings carry different properties that can determine their performance. Wire rope is constructed where a strand consists of two or more wires arranged and twisted in a specific arrangement. The individual strands are then laid in a helical pattern around the core of the rope. Once the wires are formed, they all come together to create greater strength and flexibility.

These slings work well for lifting, hoisting, towing, or anchoring loads. They’re manufactured in a variety of configurations, with 6×19 and 6×36 being the most common. When you see 6×19 or 6×36 from our website, these numbers represent the number of wires making up the strand and the number of strands wrapped around the core.

For example, a 6×19 indicates that there are 19 wires making up a strand, and 6 strands wrapping around the core. To learn more about our 6×19 wire ropes, look into our bestselling 1/2″ Galvanized Wire Rope EIPS IWRC, 1/2″ Stainless Steel Wire Rope IWRC T304, and 1/2″ Bright Wire Rope EIPS FC.

The configurations will offer different benefits for certain applications. In general, a smaller number of large outer wires offers better wear and corrosion resistance, while a larger number of small wires provides a better level of flexibility and fatigue resistance. Continue reading to learn which wire rope fits your job.

Terms that Define Construction and Properties of Wire Rope

Before immediately purchasing a wire sling, there are 7 properties that you should know about:

  1. Different Types of Wire Rope Slings
  2. Length
  3. Size
  4. Direction and Type of Lay
  5. Finish of Wires
  6. Grade of Rop
  7. Type of Core

1. Different Types of Wire Rope Slings

There are different versions of wire rope slings, ranging from single leg to 4 legs, as well as braided wire rope and domestic wire rope slings (manufactured in the U.S. with Crosby® hardware). When looking at the types of slings we offer at US Cargo Control, be sure to consider how much versatility and capability you need.

For example, a braided wire rope has increased flexibility and friction to grip loads over a regular wire rope. Adding an additional leg to the sling can add additional versatility and strength.

2. Length

the length of the wire rope sling

This is the total number of feet that are cut to size when wrapped around.

3. Size

the size and strand pattern of a wire rope

This is the measurement of the rope’s diameter and can be displayed in inches or millimeters. These sizes commonly display different strand patterns where the number of layers, wires per layer, and size of the wires per layer all affect the strand pattern. Wire rope can be constructed using one of the following patterns below or using two or more patterns.

  • Single Layer – a common example is a 7 wire strand. This has a single-wire center with six wires of the same diameter around it.
  • Filler Wire – this has two layers of uniform-size wire around a center with the inner layer having half the number of wires as the outer layer.
  • Seale – has two layers of wires around a center with the same number of wires in each layer. All wires in each layer are the same diameter.
  • Warrington – this construction has two layers of wires around a center with one diamter of wire in the inner layer, and two diameteres of wire alternating large and small in the outer layer.
  • Combination – when a strand is formed in a single operation using two or more of the above constructions, it’s referred as a “combined pattern.”

4. Direction and Type of Lay

The type of lay refers to the way the wires are laid to form a strand. They’re how the strands are laid around the core which can be regular lay, long lay, or alternate lay.

Regular Lay

The wires line up with the axis of the rope. This is where the wires are twisting in one direction, and the strands in the opposite direction create the rope. Regular lay is less likely to untwist and less likely to crush.

LAng Lay

This is the opposite of regular lay where the wires form an angle with the axis of the rope. The wires and strands spiral in the same direction and run at a diagonal to the centerline of the rope. Lang lay is more flexible and resistant to abrasion than regular lay wire ropes. The only con is this type of lay will be more likely to twist and crush than the regular lay.

Alternate Lay

Sometimes known as reverse lay, this type of lay consists of alternating regular lay and long lay strands. This unites the best features of both types, and it’s using relatively large outer wires to provide an increase of abrasion resistance.

5. Finish of Wires

steel wire rope sling in heavy industrial
Photo Courtesy: Adobe Stock

This refers to the protective coating that’s applied to the wire rope. There are three types of finishes which are galvanized (zinc-coated), stainless steel, and bright (unfinished steel).

Note that the galvanized material will provide extra corrosion resistance, and stainless steel is highly resistant to corrosion.

6. Grade of Rope

The grade of the rope means the grade of steel being used. The plow steel strength calculates the strengths of most steel wire ropes. Some classifications include Improved Plow Steel (IPS), Extra Improved Plow Steel (EIPS), Extra Extra Improved Plow Steel (EEIPS), Galvanized Improved Plowed Steel (GIPS), and Drawn Galvanized Imrpoved Plow Steel (DGEIP).

EIPS is 15% stronger than IPS, and EEIPS is 10% stronger than EIPS. Along with that, GIPS and DGEIP wires can add corrosion resistance to your application, but DGEIP wires have a higher break load than GIPS.

7. Type of Core

The type of core is what makes up the center of the wire rope. There are three types of core: Fiber Core (FC), Independent Wire Rope Core (IWRC), and Wire Strand Core (WSC).

A fiber core can be made of synthetic polypropylene fibers. The fiber cores offer greater elasticity than a steel core, but are more susceptible to crushing. This isn’t recommended for high heat environments.

A steel core can either be an independent wire rope or individual strand. The steel cores can provide adequate support, or in an operating environment where temperatures can exceed very high heat.

What’s the Difference between Wire Rope and Cable Rope?

A wire rope sling being used to lift a heavy load
Photo Courtesy: Adobe Stock

Wire and cable ropes are terms that are often interchangeable but do have one varying difference. Wire rope refers to the diameters that are larger than 3/8 inch. Sizes smaller than this are classified as cable rope or even cords. Regardless of the size difference, cable and wire rope are still classified as a “machine.” Even a group of strands laid around a core would still be called a cable or wire rope.

Tackle the Toughest Lifting Jobs with High-Quality Rigging Hardware

We know the importance of quality when it comes to lifting supplies. We carry a variety of rigging hardware, as well as lifting beams and spreader bars that are designed to lift heavy loads safely and efficiently. If you’re interested in other lifting slings, check the other types of slings we carry like nylon slings and chain slings.

Need a custom lifting sling? We can do that. We’ll work with you and customize a lifting sling to meet your specific needs.

Read more information about wire rope slings below!

How to Safely Apply Wire Rope Clips to Wire Rope Assemblies

How to Use Wire Rope Clips

What is Sling Protection, What are the Different Types of Slings, & How to Protect Them

Contact our sales team at US Cargo Control today at 866-444-9990. Our team of product experts is here to answer any questions about rigging hardware, lifting slings, and more.

What is Sling Protection, What are the Different Types of Slings, & How to Protect Them

Sling protection products can protect slings, the load, and even the load’s surroundings. Read to learn how to improve the durability of your slings and create safety and cost saving solutions in the workplace.

Are you constantly having to buy new lifting slings, or finding that your slings keep getting damaged? Are you noticing that improper use of the load or load damage is often caused by the sling itself? These issues are related to one of the most common lifting problems – lack of proper sling protection.

Luckily, we have a few tips on how to improve the endurance and longevity of your slings. In this blog, we’ll explain what is sling protection, when slings require protection, and the best sling protection products.

What is Sling Protection?

Use Corner Guards to Protect Lifting Slings

Sling protection is a common term in the lifting and rigging industry. Just like adding a screen protector to your phone, there are sling protection products that can protect your slings from sharp corners and edges.

We need to ensure the lifting sling is not cut or abraded during the lift, and the load is secured. We’re able to achieve that through products that support the durability of the lifting slings.

When researching sling protection products, it’s important to understand that some products are good for preventing abrasions while others are good for resistance to cutting. It’s also critical to know that the most common sling protection materials are polyester or nylon webbing, Kevlar, rubber, leather, and wood. While learning about your slings or the slings you wish to get, make sure to know what application you are using the sling for as well as the physical properties of the load and sling protection products.

We’re emphasizing the importance of sling protection producs because it’s typically less expensive to replace sling protection products multiple times than to replace the lifting sling.

When do Slings Require Protection?

Rigging wire rope and shackle

All types of lifting slings like nylon, polyester, wire rope, and chain must be protected from edges, corners, and protrusions. You can use products like corner guards, sleeves, reinforced eyes, and wear pads to help your slings. We also carry a line of Straightpoint Load Monitoring Loadcells to precisely measure and safely monitor the tension of loads involving wire rope, guy wire, synthetic rope, shackles, and more.

While all types of lifting slings require protection from sharp corners and edges, it’s common to use sling protection products to a synthetic sling like round slings and web slings. This is because the nylon and polyester fibers of a synthetic sling are more susceptible to cuts, tears, and abrasion than stronger sling materials like wire rope or chain. In fact, the cutting of synthetic slings during use is the number one cause of sling accidents.

The sling can make contact with the load or hardware:

  • Around any lift points like load edges, hoist rings, and eye bolts
  • Around the crane hook, shackle, and master link.
  • On load edges that could be above the hookup points

What Happens When I Don’t Protect My Slings?

How to Protect your lifting slings from sharp edges

There are several ways slings could be destroyed if you don’t use sling protection products. Without the usage of sling protection products, there is potential for:

  • Injury or loss of life
  • Higher turnover of slings, especially synthetic ones
  • Major damage to the sling, load, and around the load’s surroundings if the sling is cut, and the load is dropped
  • Damage caused to the load itself from lack of protection, especially when using wire rope and chain slings which can exert crushing forces on a load

As explained above, when you’re not using the proper sling protection, it can result in a dropped load or scratching and damaging it. This can be dangerous as this could result in injury, dismemberment, or loss of life.

In addition to that, if you’re not protecting your slings, you’re creating a higher turnover in slings and this will result in higher equipment costs. To learn more about what lifting slings you should use for the right job, read 3 Factors to Consider When Choosing Lifting Slings.

How Do Sharp Edges or Corners Damage Slings?

What is sling protection, how to protect any lifting sling

Edges can damage different types of slings in several different ways.

If you’re using chain slings, the edges can cause nicks and gouges, crushed links, and bent or twisted links. When using wire rope, the corners could damage broken wires, kinks, or doglegs. Lastly, nylon and polyester slings can be cut or abraded easily.

If your sling isn’t protected and it gets damaged, it’s more expensive to replace the sling than the sling protection product. It is much more cost-effective to replace the sling protection rather than replacing the sling itself.

Nylon and polyester slings can be easily confusing as they have a few similarities. To understand which web sling you should get, read Polyester Slings vs Nylon Slings: Which Web Sling Type is Better?

Tackle the Toughest Lifting Jobs with High-Quality Rigging Hardware

We know the importance of quality when it comes to lifting supplies. We carry a variety of rigging hardware, as well as lifting beams and spreader bars that are designed to lift heavy loads safely and efficiently. 

Need a custom lifting sling? We can do that. We’ll customize a lifting sling to meet your specific needs.

Curious about Straightpoint products and how they work? Read more information about them below!

Do You Know How Much That Weighs? Straightpoint Load Cells Do

Compression Type Load Cells: Wireless vs. Wired

How to Select a Load Cell

Contact our sales team at US Cargo Control today at 866-444-9990. Our team of product experts is here to answer any questions about rigging hardware, lifting slings, and more.

3 Factors to Consider When Choosing Lifting Slings

As objects are being lifted, the lifting sling could fail and lead to catastrophes. Read 3 factors to consider when choosing lifting slings.

One of the biggest causes of injuries and fatalities in the lifting and rigging industry is accidents caused by falls. As heavy objects are being lifted, sometimes the lifting sling can fail and lead to potential catastrophes. To prevent these situations, it is critical that you must use the correct types of lifting slings for your lifting jobs. Read 3 factors you should consider when choosing the right lifting sling, and learn the different types of slings we carry at US Cargo Control.

1. Know The Weight, Strength, and Delicacy of the Load

It’s important to know the weight and strength of the load that you intend to lift, as well as the WLL (Working Load Limit) of the sling. When you have an understanding of the object’s weight and strength, make sure you provide support from all directions. Providing support from the sides will prevent the object from falling, preventing injuries and risk to the workers on site.

The other thing that you should note is the fragility of the load you are lifting. The goal is to not only lift an object but protect the object from getting damaged in the lifting process. For lifting heavy objects or objects made of hard metals, we recommend using chain slings to perform the job.

Saw random numbers on your load-bearing equipment and didn’t know what they meant? Read what Working Load Limit, Breaking Strength, and Safety Factor mean.

2. Identify the Center of Gravity of the Load, and the Sling’s Flexibility

When you’re looking at the object you will be lifting, observe the object’s shape and design to tell you where the center of gravity is. You do not want to miss the center of the load before you begin to lift because you can potentially thrust the load and cause damage. If you’re lifting irregularly-shaped loads, consider using nylon slings as these have great flexibility and strength.

3. Do the Objects have Sharp Edges?

You’re going to lift objects that have sharp edges. Although nylon slings work best for loads needed for flexibility, the fabric will not perform well because it will be fighting against sharp edges. They will cause ripping to the sling, and this will likely result in the object falling and getting damaged.

If you’re having to lift objects with sharp edges, we recommend using chain slings or wire rope slings. We also carry corner protectors that can cover the edges of the object and protect your slings and chains.

What Are the Different Types of Slings?

Now that you know the three critical factors to consider when choosing a sling, you need to learn the many different types of slings there are. This will help you identify which sling is worth the investment for your lifting situations.

Nylon Slings

US Cargo Control nylon lifting sling

Known as synthetic web slings or nylon web slings, our nylon lifting straps perform well for lifting breakable, delicate objects. Its heavy-duty synthetic material has great stretch and flexibility that help the slings mold to the shape of the load. Not only that, the nylon lifting sling’s material is treated to improve abrasion resistance and reduce wear, even in the most rigorous lifting applications.

They are lightweight, easy to handle, and offer a wider body with more stretch than a polyester sling. Its attributes make synthetic slings a popular choice for rigging purposes and are essential to have around, but they should not be used in extreme or rugged conditions. Nylon rigging straps will wear down more quickly than other types of slings if you go against its limits!

Chain Slings

If you’re depending on a sling that requires extra strength and durability, the chain sling is your best choice. The chain lifting sling is the strongest and most durable type of sling and is highly popular to use for heavy lifting operations. They will perform better than polyester round slings or nylon slings because they’re more durable, tolerant to hot temperatures, and cut-resistant. When we say chain slings are tolerant to hot temperatures, this means they are useful for lifts in extremely hot temperatures or to secure extremely hot objects.

We offer three trusted brands of lifting chain slings, Crosby, KWB, and Pewag. We offer chain slings from these brands because we want you to have the highest-quality slings that will perform the lifting job successfully. We sell these in two types, standard and adjustable, and we also offer custom options if needed.

We recently added a full line of Grade 120 chain and components that are now available at US Cargo Control. Read more about Grade 120 and its benefits.

Polyester Round Slings

Polyester slings can be confused with nylon slings due to their material that is also made of a web-like fabric. The difference is that while nylon slings stretch easily, polyester round slings have a little stretch to them. These are useful to have for lifting operations where strength is needed, but not a lot of stretch needed.

Manufactured in the USA from a continuous loop of polyester yarn that creates exceptional strength, the round slings are versatile, pliable, convenient, and cost-effective. Because of their many benefits, you can use these in vertical, choker, or basket hitches, making them effective to lift a wide variety of cargo!

Curious about the differences between nylon slings and polyester slings? Read Polyester Slings vs Nylon Slings: Which Web Sling Type is Better?

Wire Rope Slings

US Cargo Control wire slings

Known as steel cable or wire sling, these are more durable than synthetic slings and more cost-effective than chain slings. Wire rope slings are an excellent choice not only for lifting, but also for hoisting, towing, or anchoring loads. Its fabrication offers abrasion-resistance and heat-resistance, as they are made by weaving individual strands or wire around a core.

Wire rope slings are favorable by riggers as they can come in a wide variety of materials, diameters, and configurations. Each steel wire rope configuration will offer different benefits and are suited to certain applications. For example, a smaller number of large outer wires offers better wear and corrosion resistance, while a larger number will provide better flexibility and fatigue-resistance.

If you would like to learn more about wire rope configuration, see our category on wire rope.

Tackle the Toughest Lifting Jobs with High-Quality Rigging Hardware

We know the importance of quality when it comes to rigging supplies. We carry a variety of rigging hardware, as well as lifting beams and spreader bars that are designed to lift heavy loads safely and efficiently.

We also do custom orders! Need a custom lifting sling? We can do that! We can customize a lifting sling to meet your specific needs.

Contact our sales team today at 866-444-9990. Our team of product experts is here to answer any questions about rigging hardware, lifting slings, and more.

How to Tell When It’s Time for New Rigging Gear

Whether you’re inspecting wire rope, chain slings, synthetic web slings, round slings, or any type of rigging hardware, here are the warning signs of potential rigging equipment failure.

rigging gear inspection checklist

Stay safe and compliant with these rigging gear inspection tips.

The best way to tell if it’s time to upgrade your rigging and lifting gear starts with regular inspections, ideally before and after each use. When you’re trying to get a job done, it’s easy to fall out of the habit of inspecting your gear. But, compared to the alternatives options of either failing an official inspection or having your gear fail while in use, regular rigging gear inspection is well worth it.

So, whether you’re using wire rope, chain slings, synthetic web slings, round slings, or any type of rigging hardware, here are the warning signs to look for when inspecting your rigging gear.

Wire Rope Inspection

inspection checklist for wire rope

Wire rope is often combined with wire rope clips and thimbles and also used in wire rope slings that are great for a variety of lifts. It’s also commonly used on specialty vehicles, like tow trucks, as a winch line. Between load stress, environmental conditions, and abrasion, there are many factors that can shorten the life of wire rope.

Regularly inspect your wire rope and discard it if any of the following is evident:

  • Excessive broken wire
  • Distortion or kinking
  • Severe corrosion
  • Shiny worn spots on the outside of the rope
  • A one-third reduction in the outer wire diameter
  • Damaged or displaced hooks, link, rings, or other end fittings

Chain Sling Inspection

inspection checklist for chain slings

Yes, even the strongest chain slings, like a mighty grade 120 chain sling, can become overly stressed and eventually unsafe to continue using. Heat, chemicals, and heavy loads all take a toll on a chain slings longevity.

If you notice any of the following on your chain slings, cut them up into 3′ to 4′ lengths (to prevent salvaging) and then recycle them:

  • Stretched or overly-elongated links
  • Kinks or binding
  • Nicks or gouges in links

Synthetic Web Sling Inspection

inspection checklist for synthetic web slings

The softness and flexibility of polyester and nylon lifting slings make them great for lifting fragile or expensive cargo. But just because they’re lifting delicately, doesn’t mean that can’t become worn out and dangerous to use.

Discontinue use and cut the sling into 3′ to 4′ lengths (and cut the eye) if you notice any of the following:

  • Snags, tears, or cuts
  • Melting or charring of any surface area
  • Acid or caustic burns
  • Broken or worn stitching
  • Elongation that exceeds manufacturer’s recommendation
  • Distortion of any fittings

Polyester Round Sling Inspection

inspection checklist for polyester round slings

Round slings are a versatile, strong, and cost-efficient tool for lifting a variety of cargo types. Polyester round slings contain a continuous loop of polyester yarn inside and a durable polyester fabric on the outside that is usually color-coded by lifting capacity.

While round slings are able to handle large loads, even the smallest rip, cut, or tear is enough to make it unsafe for use. If you notice these issues during inspection, cut the sling in half to retire it from service:

  • Exposure of the yarn core or broken or damaged yarn
  • Heat damage
  • Discolored, brittle, or stiff areas
  • Acid or caustic burns

Rigging Hardware Inspection

inspection checklist for rigging hardware

Common pieces of rigging hardware used for lifts include: shackles, turnbuckles, hooks, links and swivels, rings, wire rope clips, and thimbles. The integrity of these smaller items is vital to rigging safety.

Prior to using rigging hardware, visually inspect each piece and discontinue use if you notice the following:

  • Excessive nicks, gouges, or corrosion
  • Bent, twisted, elongated, or cracked load-bearing components
  • Reduction in original dimension by 10% or more
  • Indication of heat damage
  • Missing or illegible load rating information

Purchase Smart, Use With Confidence

If any of the above signs are evident during your routine inspection, it’s likely time to replace your rigging gear. Similar to knowing your rigging inspection checklist, it’s helpful to learn what to look for when buying rigging and lifting gear so you can always ensure that you’re using the best equipment for the job, and enjoy years of safe use.

For official rigging equipment inspection requirements see OSHA section 1926.251.

4 Tips for Buying the Right Rigging & Lifting Equipment

If you work in the rigging and lifting industry you know that, when lives are on the line, close is never close enough. Safety measures, procedures, and equipment specs have to be spot-on.

Maintaining a safe job site starts with having the proper equipment for the job. But, with thousands of different rigging products, each with their own distinct characteristics, capabilities, and reputation, many riggers face the struggle of trying to choose the correct rigging and lifting equipment for the job.

Here are the 4 main things to pay attention to when deciding which rigging and lifting products are best for your particular job.

 

1. Assess what your lifting

To start, you need to assess the object or objects you are needing to lift or rig up. Does the object have sharp corners? Where is the center of gravity in your load? How much lifting space do you have? Asking these questions first will help to narrow down the potential rigging gear you can safely and effectively use for the job.

 

 

2. Know your Load Limit

working load limit on lifting gear for safety

Working load limit is the maximum weight that can safely be applied to a given piece of rigging equipment. It’s different for each individual piece of equipment, so be sure to pay close attention to this when selecting your rigging and lifting gear. Just one weak area puts the entire operation at risk. Check the weight of your load first, then ensure that you only buy equipment that is rated for that weight or more.

 

 

3. Consider Temperature & Environment

tips for choosing best rigging and lifting equipment

In applications that experience extremely high or low temperatures, certain equipment may not operate properly. For example, if you’re working in a high-heat environment, you will want to use wire rope with an independent wire rope core (IWRC) instead of a fiber core (FC). Also, consider the worksite environment. If saltwater is a factor, buy stainless steel rigging gear to prevent corrosion.

 

 

4. Opt for Quality

high quality lifting and rigging gear for manufacturing industry

Strength and durability is the name of the game when it comes to rigging and lifting gear. For the best chance of avoiding accidents and equipment that wears out quickly, you’ll want to ensure that you’re purchasing high-quality rigging equipment from trustworthy sources. It may not always be the most affordable choice, but it will be the smartest choice in the long run.

 

The importance of buying the right equipment is clear when you consider the stakes of lifting and handling heavy loads. Don’t guess. Take the time to thoroughly evaluate the job at hand before buying. When you do buy rigging and lifting supplies, be sure to check all the manufacturer specifications and ask questions if you’re unsure.

USCC has a team of dedicated product consultants that are just a phone call away. If you have product questions or would like to place an order over the phone instead of on our website, give them a call at 800-404-7068.

 

How to Safely Apply Wire Rope Clips to Wire Rope Assemblies

This video shows you how to safely apply wire rope clips to wire rope assemblies. Depending on the size of your assembly, two to three wire rope clips are generally required. See below for a full transcript of the video. 

 

 

For more information on the differences among wire rope clips and how to choose the correct one, see our How to Use Wire Rope Clips post.

Safety Notes: Always inspect wire rope for wear and abuse before applying wire rope clips. Apply wire rope clips over bare wire rope only. Use wire rope thimbles to protect the eye from being crushed and to prevent wear and abrasion on the rope.  Never use a wire rope clip to directly connect two straight lengths of wire rope.
 

An important phrase to remember when applying a wire rope clip is “Never Saddle a Dead Horse”. This means you should never apply the saddle side of the clip over the dead end of the rope – the live end should always rest in the saddle. See above video for a demonstration. 

Step 1.   

Turn back the specified amount of rope from the thimble. Apply first clip one base width from the dead end of the rope. Tighten nuts evenly, alternating from one nut to the other until reaching the recommended torque. 

Step 2.  

If only two clips are required, apply the second clip as near the loop or thimble as possible. Remember, U-Bolt over dead end. Tighten nuts evenly, alternating until reaching the recommended torque.  

When applying more than two clips, apply the second clip as near the loop or thimble as possible, turn nuts on second clip firmly, but do not tighten.  

Step 3.   

Space additional clips equally between the first two. Apply tension and then tighten the nuts on each clip evenly, alternating from one nut to the other until reaching recommended torque. 

 

Purchase Wire Rope Clips and more from US Cargo Control 

From wire rope, wire rope clips, and wire rope thimbles, to chain hoists and material handling equipment, US Cargo Control has your rigging and lifting equipment needs covered. Visit US Cargo Control.com or call 866-444-9990.  With teams of dedicated consultants, we make sure you get what you want, when you need it.  

Sales Team Q&A: Guy Wire

Our latest Q&A responds to common questions the US Cargo Control sales team answers about rigging, specifically guy wire and its components. Guywire

Why is it called guy wire? 

Guy is defined as a rope, cord or cable used to steady, guide or secure something.  Guy wire is used to stabilize and secure antenna and utility towers.  The structure stays in place when the wire is attached to the tower and then anchored to the ground, creating a diagonal line. The tension from the cable and angle of securement stabilizes the tower, helping it withstand weight and wind.

1x7-EHS-Galvanized-Strand_1_375
Galvanized Guy Strand 1×7 and 1×19

 

What’s the difference between drop forged, malleable and precision cast in wire rope clips?

Drop forged wire rope clips are made for heavy duty jobs and are great as guy wire clamps. The drop forged steel coating provides extra strength and protection from the elements. However, these clips are not meant for overhead lifting.  They meet federal specifications FF-T0276b. Type III.

Precision cast wire rope clips are made of marine grade stainless steel and are typically used for water work. They are resistant to the salt in sea-water and materials used to de-ice. Their resistance to corrosion makes them ideal for harsh elements. These clips meet FED.SPEC.FF-C-450D.

Malleable wire rope clips are a softer clip typically used for light-duty work. They are often used to clamp the loose end of wire rope after forming an eye.

How is a shoulder eye bolt different from a regular eye bolt? 

Shoulder eye bolts and regular eye bolts differ in their intended uses for rigging. A regular eye bolt can be used for many different jobs, but for rigging, it should only be the tool of choice for vertical techniques. However, shouldered eye bolts can be used for angular jobs. The shoulder helps protect the shank from bending.  Keep in mind, angle loading reduces the bolt’s rating.

Questions

If you have questions, be sure to contact the US Cargo Control sales team at 800-866-3585. People can also email TowerProducts@USCargoControl.com.

 

Coated Cable



US Cargo Control offers 7×19 coated cable in stainless steel and galvanized finishes.  These coated cables are composed of 7 strands with 19 wires per strand, producing a cable that offers flexibility and superior resistance to corrosion.  As a coated cable, the protection intensifies, adding an extra layer to fend off dirt, grit, moisture and other abrasions.  Coated cable also seals in lubrication, reducing wear on accessories.  To shop coated cable and accessories, visit USCargoControl.com.

 

Stainless Steel Aircraft Cable



 

Stainless steel aircraft cable  from US Cargo Control comes in an aircraft cable type 304 or type 316 stainless steel finish.  Type 304 stainless steel aircraft cable is excellent at resisting corrosion.  The 7×19 construction of the cable provides flexibility and strength.  Type 316 cable provides the highest level of protection against corrosion.  Commonly referred to as marine grade stainless steel, it is ideal in high moisture environments.  For additional protection, vinyl coated stainless steel aircraft cable is also available.  To shop all of our wire rope and accessories, visit USCargoControl.com.

Stainless Cable



 

US Cargo Control offers a wide variety of stainless cable to fit your application.  Stainless cable can be found in the 6×19, 6×37 and 7×19 classes.  Stainless cable consists of wires, strands, and a core formed into a spiral pattern, which creates a strong, durable rope.  It’s excellent for outdoor use or harsh conditions due to its ability to not rust or corrode. For more information on stainless cable, or to shop our wire rope and accessories, visit USCargoControl.com.

IWRC Wire Rope



US Cargo Control carries a wide variety of wire rope for your application.  IWRC wire rope or independent wire rope core refers to the construction of the core of a wire rope.  When the outer strands of wire are wrapped around a steel core, it reduces stretch and increases the strength of the wire rope.  This also provides a higher resistance to crushing.  IWRC wire rope comes in bright wire, galvanized and stainless steel finishes.  For more information on IWRC wire rope, visit USCargoControl.com.