Polyester Slings vs Nylon Slings: Which Web Sling Type is Better?

Are polyester lifting slings better than nylon lifting slings? This is a question our lifting and rigging product experts commonly get and the answer, as it often is with rigging gear, is that it depends on the job at hand.

Before we dive into the key differences between nylon slings and polyester slings, there are many similar advantages to these two types of synthetic slings that are important to know.

Advantages of Synthetic Webbing

1. Ideal for delicate loads

One of the most common reasons for a rigger to use synthetic slings instead of wire rope slings or chain slings is th fact that they won’t scratch or crush your load. That’s why synthetic slings are extremely popular in the construction industry and with ship haulers.

2. Cost-efficient

Synthetic slings are also an attractive choice due to their lower cost. If you’re wondering whether nylon slings are cheaper than polyester slings, don’t. The prices are more or less the same, and your focus should be on choosing the right sling for the job.

3. Lightweight

Compared to wire rope and chain, synthetic slings are much lighter, making them easier to transport and handle. Again, nylon is typically a little heavier than polyester, but it’s not much of a difference when you consider the weight of chain and wire rope.

4. Strong

It’s true that nylon is stronger on an individual fiber level, but a polyester sling can be made just as strong as a nylon one by adding more threading. And both types can easily lift several thousand pounds. So while it’s important to use a lifting sling that’s rated for the load your lifting, this won’t affect your choice between nylon and polyester.

Physical Differences

Now that you know how they’re similar, let’s look at the differences between the physical characteristics of nylon and polyester to determine which material type is best for your job.

Nylon has more stretch

This is one the most important differences between nylon slings and polyester slings. While nylon slings have more give to them (about 7 to 10 percent stretch when at WLL) that does not mean they are weaker than polyester (typically 2 to 3 percent stretch at WLL). The main reasons you would want more or less stretch when lifting a load include overheight lifting room and the potential for “snapback”.

If you have height limitations, polyester is probably the better choice. If your load could bounce around a lot, the extra stretch of nylon will reduce the danger of the strap snapping back at you or others. This difference in the stretch is why you typically see recovery straps made of nylon and tow straps made of polyester.

Polyester is softer and more flexible

Both nylon and polyester slings are good for delicate loads, but if you’re wondering which one is best for the most delicate loads, it’s polyester. The chemical coating on nylon webbing gives it a slightly more coarse texture.

Polyester is also a bit more flexible than nylon. By flexible, I’m not talking about stretch but rather the ability to wrap tightly around a load and grip the most surface area.

This is an important difference, especially when choosing between nylon endless slings and polyester endless slings.

nylon round endless lifting sling
Nylon Endless Sling
polyester round endless sling
Polyester Endless Sling

Environmental Differences

Another key question to ask when choosing between nylon slings and polyester slings is, what are the environmental conditions? There’s a reason why ship haulers and those in marine environments prefer polyester slings, they absorb less water and are just a bit more resistant to UV rays. But, you also need to consider the differences when it comes to chemical resistance.

Nylon slings can’t resist acids or bleaches

Avoid using nylon slings if you’re operating anywhere near sulfuric, nitric, hydrochloric, or phosphoric acids. Nylon is also unresistant to oxidizing bleach agents such as sodium hypochlorite, hydrogen peroxide, sodium percarbonate, and calcium hypochlorite.

Polyester slings can’t resist ethers or alkalis

On the other hand, polyesters Achilles heel is ethers and alkalis. Among other chemicals, this includes diethyl ether, dimethyl ether, sodium hydroxide, potassium hydroxide, calcium hydroxide, calcium carbonate, and magnesium hydroxide.

Polyester Slings

best eye to eye lifting sling

browse all polyester sling

Conclusion

In short, synthetic lifting slings are a great choice due to their ability to handle delicate loads, lower cost, lightness, and impressive strength. In the polyester sling vs nylon sling matchup, the winner is whichever one meets the demands of your specific job best.

Nylon slings have more stretch but can’t be used near acids or bleaches. Polyester slings are softer and hug to load surfaces better but can’t be used near ethers or alkalis.

If you have any additional questions about nylon slings or polyester slings, give our rigging product experts a call at 800-404-7068.

Cargo Webbing: What’s the Difference Between Nylon and Polyester?

Cargo webbing is used for a variety of tie downs, cargo nets, seat belts, etc., but there’s a difference in the fabrication of the webbing. Polyester webbing and nylon webbing are the two major categories, along with another polyester fabric webbing that’s known in the industry as seatbelt webbing. While all three may seem similar, some differences will make one better than another for certain applications.

 Nylon webbing

Nylon Cargo Webbing
Nylon Webbing

 

Nylon webbing offers a good combination of both stretch and strength. It has the ability to stretch about 5% to 7% at rated capacity and approximately 30% at break strength. This snap-back quality makes nylon cargo webbing a great choice for recovery straps because of its ability to recover stuck vehicles.

Nylon tie downs should not be used in temperatures above 194 degrees F (90 degrees C) or below -40 degrees F (-40 degrees C). It should also not come in contact with objects above or below those temperatures, including anchor points, the cargo being secured, or a vehicle.

Polyester webbing

polyester cargo webbing
Polyester Webbing

 

Like nylon webbing, polyester webbing is strong and durable, but it lacks the ability to stretch the same way nylon does. This makes it ideal for tie-down applications where cargo must stay secure and not be allowed to bounce: ratchet straps, motorcycle tie downs, cargo nets, etc. Polyester cargo webbing is also versatile as you can add your own tie-down hardware to create your own custom tie-down straps.

Like nylon, polyester webbing should not be used in temperatures above 194 degrees F (90 degrees C) or below -40 degrees F (-40 degrees C), or come in contact with objects (anchor points, cargo being secured, or vehicle) above or below those temperatures.

Seatbelt webbing

Polyester Seat Belt  Cargo Webbing
Polyester Seat Belt Webbing

 

Seatbelt webbing is also a polyester webbing so it offers the same benefits of strength and little stretch. While still a tough, high-quality webbing, it is a less expensive option because it’s offered in just one size and three color options. Seat belt webbing also has a thinner profile than typical polyester cargo web, so it’s great for lighter duty applications such as bag handles, life jacket straps, etc.

When using seatbelt webbing for any application, you should also follow the maximum and minimum temperatures guidelines outlined above for polyester webbing.

Sizes and strengths of cargo webbing

Webbing ranges in widths from 1” to 12” and various lengths. It’s important to keep in mind that a longer strap will not increase the break strength ability, but a wider width will. Each strap width should include tensile strength information, which is the maximum amount of stress a strap will take before failing or breaking. The work load limit will vary by the use or application.

What’s the Difference Between Seat Belt Webbing and Polyester Webbing?

3321-polyester-seat-belt-webbing-2-x-600-roll-mixed-gray_1_640A: Seat belt webbing is actually a polyester webbing but it’s slightly thinner and typically has a lower tensile strength than regular polyester webbing that’s usually used for ratchet straps, cam straps and winch straps. It obviously gets its name from its main use as webbing used for seat belts and other automotive restraints, but it can also be used for a variety of other applications: tents, tarps, bag straps, camping gear, boating accessories, garden and lawn equipment uses.

Both regular polyester webbing and seatbelt webbing have excellent qualities for rugged use: it will not shrink, rot, mildew, or mold, because it absorbs very little water. It also stands up well to UV rays and many acids.

You can see all of our cargo webbing here: Webbing.

Have a question for our sales team? Send us a message in the comment box below!

Replacing Tie Down Straps

If the webbing on your ratchet straps, cam straps or winch straps is showing signs of wear and tear, they need to be replaced. According to the Web Sling and Tie Down Association (WSTDA), web tie down straps should no longer be used if tears, holes, snags, cuts or embedded particles are evident that could raise doubt about the tie down’s strength. They should also be replaced if the work load limit (WLL) information is no longer visible on the webbing.

Replacement tie down straps

Replacement strap: fixed end with ratchet and flat hook
Replacement strap

 

Replacement tie down straps are a great choice for because you’ll need to buy only the end that needs replacing.  Several options are available, including wire hooks, chain extensions, and flat hooks. Replacement straps can also be used to easily turn a winch strap into a ratcheting strap. Polyester webbing replacement straps can be purchased in 2″, 3″ and 4″ widths.

 

Polyester cargo webbing

Polyester cargo webbing: 2" width
Polyester cargo webbing

 

If you only need to replace the webbing on your current ratchet straps, cam straps or winch straps, you can purchase polyester cargo webbing by the foot. This way you only buy the lengths that you need. It’s available in a range of colors and in 1″, 2″, 3″, and 4″ widths.