Ratchet Straps & Tie Downs 101: Working Load Limit and Break Strength Explained

When transporting cargo using a pickup truck, trailer, or a hitch-mounted carrier, ratchet straps and tie downs are the most dependable and safe harnesses you can utilize to ensure your cargo is secure during transportation. These come in many varieties and lengths for lightweight to heavy loads.

Ratchet straps and tie downs are always marked with a working load limit (WLL) and the break strength. These components denote how much weight the object can handle. Sadly, not many people in the cargo industry fully understand the difference between the two terms.

If you happen to deal with tie down and straps, you need to ensure that heavy loads and fragile materials are well secured by the strap without breaking.

Here, we seek to explain the words break strength and working load limit in detail.

  1. Break Strength

Any time you come across the break strength of a ratchet strap or a tie down, it means the point at which any load-bearing part of the strap will fail or simply, the maximum comfortable weight the strap can handle before it fails. Break strength denotes the weakest point of the tie down’s end fittings, webbing, or tensioning device.

For instance, when a ratchet strap is constructed with webbing, end fittings, and a ratchet with 5,000 lb. break strength, it means that the overall break strength of the product will remain at 5,000 lb. However, if the very same strap or tie down was constructed with a ratchet that had a 4,000 lb. break strength, this would bring down the overall product strength to 4,000 lb. regardless of the webbing rating of 5,000 lb.

  1. Working Load Limit

The working load limit often marked as WLL, refers to the maximum weight that a ratchet strap or a tie down can support on regular use without breaking. In other words, this is the maximum allowable load designed for each tie down or strap by the manufacture and which shouldn’t exceed one-third of its breaking strength.  Hence a strap featuring a breaking strength of 9,000 pounds will have a working load limit of 3,000 pounds.

Knowing your WLL is crucial for your cargo safety. Going above it by even a single pound of your WLL can make shipping disastrous. To be secure, provide more wiggle room as far away from the WLL.

Working load limits and break strengths help secure your load on the road. It is not uncommon to run into issues while traveling. Sometimes, the car in front of you can break at high speeds forcing you to slam on your brakes so hard. Other times, a motorist can pull unexpectedly making you swerve out of the way into safety. If your tie down and ratchet straps have wrong ratings, your cargo might blow out during these harsh traveling conditions. By ensuring your WLL and break strength ratings are correct, you adhere to safety guidelines and make the transport industry a bit safer. And, of course, you get to avoid penalties and fines from the local authorities.