If I Say Work Load Limit and You Say Breaking Strength, Who’s Right?

When it comes to off-road recovery gear, there has always been a bit of a dispute when it comes to weight ratings and making sure you match the components in your gear bag to the potential use that they are lying in wait to fulfill.

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To begin to wrap our minds around the issue at hand, it’s vital to understand the terms and what they actually mean. If you went to buy a new car and the bold MPG numbers on the window sticker were in the single digits, you would be wise move along to some other dealership, wouldn’t you? But what if you thought that a lower number was actually preferred, like in a golf score? Could such confusion be the root of how our highways have become congested with massive fuel-guzzling SUV’s? We just didn’t know any better…right?

You will likely see two different terms commonly tossed around when shopping for shackles, straps and recovery appliances today. The first one is “Breaking Strength” which, admittedly, sounds about as cool as a term possibly can. Doesn’t it? This number is usually a gargantuan figure with tons of zeroes and it’s easy to be swept away by the size of the number when positioned next to a word like strength. The Breaking Strength can be defined as the average force at which any given product, in brand new condition, has been found to break when a constant and ever-increasing force is applied to it in a direct line and at a uniform rate of speed. Essentially, it’s a number arrived at in a testing laboratory under strict conditions; a number whose actual existence outside of that laboratory is highly unlikely.

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I like to think of the term Breaking Strength in a slightly different fashion that helps put its value in perspective. I’m reminded of a story I read once about a Soviet airman during World War II named Ivan Chisov. While embroiled in a heated and volatile air battle with German forces, Ivan’s bomber took on heavy damage. While disaster for the crew seemed imminent, Chisov knew that parachuting from the failing aircraft while in the midst of an intense aerial dogfight would give the German fighters a slowly descending target at which to take aim, making him an unwilling sitting duck. For that reason, Ivan exited the plane and rocketed towards earth, chute unopened, waiting until he was well-clear of the fray to deploy his chute and slow his descent. Ahhh…the beauty found in such a calculated plan!

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Contrary to his crafty plan, falling at nearly 150 miles per hour unfortunately caused Chisov to black out completely, making him a less-than-likely candidate to execute the timely pull of the ripcord, as his hastily-made plan required. Henceforth, falling from an altitude of more than 22,000 feet with nothing more to break his fall than the clothes he had on and the snowy bank resting below seemed a certain and fatal end. Somehow, despite insurmountable odds, Ivan Chisov survived the fall and lived to fly again, only months later, after recovering from his slew of injuries.

While Ivan’s story is pretty remarkable, it stands to show that amazing things can happen when the conditions are just right. It goes without saying that the Russian Air Force did not revise their training manuals based ON Ivan’s experience to show that a standard airman can survive a fall from 20,000 feet due to their incredible inherent breaking strength, although in certain scenarios under precise conditions it is somehow possible. It is certainly NOT the rule and to count on it as such would be a first step in the wrong direction.

That’s where the WLL, or Working Load Limit, comes into the picture. When defined, the WLL is the maximum load which should ever be applied to the product, even when the item is new, with uncompromised integrity and the load is uniformly applied. When the WLL is applied to any scenario, it introduces a factor of safety into the equation so that the margin for an accidental failure of equipment is virtually eliminated. For that reason, the WLL is usually 1/3 of the products breaking strength. This introduces a little bit of breathing room into the equation; accounting for things that are not as ideal as the laboratory conditions. Things like the resistance of the aired-down tires, the tree that is 25 degrees to the right of the vehicle instead of perfectly inline or the D-shackle that might have tumbled out of the tailgate a time or two in the past.

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Since the Working Load Limit is still founded on a straight line pull scenario, it is of vital importance that every effort is made to abide by this standard when rigging for vehicle recovery. This standard would make necessary a variety of items to suit the wide array of scenarios one would encounter on the trail: straps, shackles, pulleys, snatch blocks and the list goes on. Much like playing Red Rover in grade school, your recovery chain is only as strong as its weakest link. If you are wheeling in a newer Wrangler JK Unlimited, you need to know the weight of the vehicle is around 5,000 pounds and then plan your gear accordingly.

In the same breath, don’t outfit your recovery gear for your JK 4-Door and then think you can safely snatch a stray ditch-bound semi out on the way home. You’ll need some superhero-grade powers or an advanced Engineering degree…or both. Even if your snatch strap is rated for 10 million tons, the trailer hitch you hook it to is not even close to being up to the task. The importance of sizing up the task and assembling appropriate gear to accomplish it safely is critical; otherwise, we don’t jump out of the plane.5Bottom line? Consider a products breaking strength as a “good to know” while keeping the WLL as the number to count on. Prepare for any possibility, plan for every situation but always make sure safety is the tool you rely on most often. Keeping all your recovery gear in good working order is as important as selecting the right gear that is rated adequately for the job at hand will help insure a safe and rewarding wheeling experience. OlllllllO2106b4ca367891a36776fcdb10f2edd9

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