In the world of webbing tie downs for commercial trucks , the ratchet strap and winch strap are playing a huge role in securing truck load, cargo strap can be used inside the box trucks and on the flat beds , while winch tie downs almost in all cases are being deployed with truck winches on flatbed only . As we all know truck tie downs are much more than just ratchet straps and winch straps , for instance there are grade 70 chains , load binders, logistic strap , etc.

We’re not going to talk about regular tie downs but the reflective straps which have reflective strips on the webbing , in dark environment the reflective strips can be seen from far away , this sounds like a nice feature, is it? When it comes to safety, even 1 or 2 percent reduction of risk of collision should encourage people to get the reflective ratchet straps. Due the reflective tie downs are relatively new on the market, we don’t have much proof of safety benefits, though we can understand that if people can easily see the straps on the truck in low light, the probability of collision will be reduced.

Now compare the price of regular tie down to reflective tie down, get online you will find a lot of interesting information, a simple search tells us that the reflective ones are about 10% more expensive then non reflective ones, tie down straps are usually sold at $10-$12, reflectives will increase the price by $1 to $2 , IMHO it should be more expensive, spend extra 10 dollars or more to get 10 reflective tie downs is not bad, these straps will last more than a few months, the conservative estimation will be at lease 6 months, you almost spend nothing to get the security feature offered by reflective tie downs! If its me I will go all the way for the reflective straps.

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We all know that when assemble tie down strap and ratchets together we get ratchet strap, when the ratchet buckle is replaced by cam buckle then you get the cam buckle straps. Cam buckle tie downs are only for light duty use, and 2” cam buckles are the biggest size we will see in the real world use, and it’s still light duty. Compare to cam buckle the ratchets are stronger and more widely used, the available sizes of ratchets are 1”,2”,3” and 4”, and the ratchet buckle generally has higher working load limit than the  cam buckle, they have working load limit of 3,333lbs, 5,400lbs and 5,400lbs respectively, these assemblies have design factor of 3:1, thus the minimum breaking strength is 10,000lbs, 16,200lbs and 16,200lbs respectively.

So far we talked about tie down devices for flatbed trucks or similar commercial vehicles, in reality semi trailers are much more than flatbeds in numbers, since they are box trucks the tie down needs are different, you will see most semi trailers have E Track installed and use logistic strap . It is estimated that 80% trucks are box trucks, and the e track tie down system is just for box trucks , so logistic straps are most popular tie down straps. With 1,000lbs safe load  limit and 3,000lbs minimum breaking strength, e track tie downs are not as strong as flatbed tie down straps, It’s understandable that e track straps have lower working load limit, because the box truck wall will provide strong support for the loads inside, and the truck wall will prevent the loads from falling off, rolling over, tilting and some other dangerous movements. With the help of e track cargo bar, rope tie off and some other e track tie downs and accessories, it’s pretty easy to secure loads inside the box trucks, but easy doesn’t mean not important, you still have to look out for any risks may present in the process of transportation, so secure your loads as reliable as you can, use the right tie down equipment for your job.

In first paragraph we talked about design factor of ratchet tie downs, which is 3:1, so the working load limit is 1/3 of maximum breaking strength for ratchet straps, in the mean time the design factor of grade 70 tie down chains is 4:1, so the chains can support heavier load, and are more resistance to abuse, such as high/low temperature, moisture, while tie down straps usually only work well under normal condition. The standard material of which tie down webbing is made is nylon webbing or polyester webbing, depends on different tie down applications. The typical application for nylon webbing is motorcycle tie down, while polyester webbing is ideal for tying down concrete pipes. Elongation, tensile strength, abrasion and environment, these have to be taken into consideration when making tie down strap. There are mandated criteria for breaking strength and elongation of the tie down straps , while the abrasion and environment are mostly estimation and subjective sometimes, different area may have different requirements. Therefore the manufacturer may have to make these tie downs to different standards.

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The ratchet straps are just the assemblies of ratchet buckle and tie down webbing, but if we use cam buckle in place of ratchet buckle in the assembly we have cam buckle tie down, it’s as simple as that. Cam buckle tie downs are only for light duty use, and 2” cam buckles are the biggest size we will see in the real world use, and it’s still light duty. Unlike cam buckle, ratchet buckle are much stronger, and 2”,3” and 4” ratchet buckles are used in industrial grade applications, such as heavy duty transportation, the typical working load limit for 2” tie downs is 3,333lbs, for 3” and 4” which is 5,400lbs, since these tie downs have design factor of 3:1, the minimum breaking strength is 10,000lbs and 16,200lbs.

Of course what we discussed above is mainly for flatbed trucks and some other kind of vehicles, in reality semi trailers are much more than flatbeds in numbers, since they are box trucks the tie down needs are different, you will see most box trucks have E Track installed and use logistic tie downs . It is estimated that 80% trucks are box trucks, and the e track tie down system is just for semi trailers , so e track straps are most popular tie down straps. And these straps are not as strong as the one we use on flatbed truck, the working load limit of typical e track straps is 1,000lbs, with minimum breaking strength of 3,000lbs. It’s easy to understand that why e track straps are not as strong as regular ratchet tie down straps, inside the box truck the loads already have strong support, at least there is no risk of falling off, all the e track straps will do is to fixate the loads more than tie them down. You also have e track cargo bar, shoring beam, e track tie off, etc. at your disposal, with e track tie down straps you will be able to secure any kind of cargo , make the transportation experience as it should be , but remember that you can never be more careful when it comes to your precious truck and load , make sure your cargo are tied down properly all the time.

We already discussed the design factor of ratchet straps, it is 3:1 and for the record all this says is that safe load limit of tie down straps is 1/3 of it’s breaking strength, while grade 70 transport chains which have a design factor of 4:1, that means the transport chains will work in more tough environment than tie down straps, which usually are chose for regular loads. The standard material of which tie down webbing is made is nylon webbing or polyester webbing, depends on different tie down applications. Nylon webbing has better elongation than polyester, so for shock absorption wise nylon is ideal material while polyester usually is used to make tie downs for heavy equipment. Elongation, tensile strength, abrasion and environment, these have to be taken into consideration when making tie down strap. Breaking strength has to reach the recommendation level no matter what, and elongation has to meet the requirement, abrasion and environment sometimes are not that clear cut, when designing tie downs we may have to consider the most extreme conditions these tie down straps may be in, or we may just consider the normal transportation environment.

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