It’s a well known fact that when we put ratchet buckle and tie down webbing together we get ratchet strap, by this logic the cam buckle strap is just the cam buckle with tie down strap, why I am not surprised? Most likely these cam buckle straps are used on pick up trucks or passenger cars for luggage tie down, and small cam buckle(1”) are more popular than big ones(2”). 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, with 3,333LBS, 5,400LBS working load and a design factor of 3:1, these ratchets have 10,000LBS and 16,2000LBS breaking strength respectively, which are pretty strong for most tie down applications.

Of course what we discussed above is mainly for flatbed trucks and some other kind of vehicles, there are another category of ratchet straps for semi trailers, ratchet e track strap , these tie down devices will be used with E Tracks installed inside the semi trailer. By estimation, there are almost 80% trucks on the road are box trucks, so these e track straps are supposed to the most popular ones by volume. 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. Coupled with e track cargo bar, rope tie off, e track hardware(such as D ring with E fitting), shoring beam, e track tie downs can be used to secure any kind of loads, and secure them reliably, but you still have to pay close attention to the safety of your load , easy to secure is not an excuse for careless tie down practice.

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, while grade 70 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 most common materials in making tie down webbing are nylon and polyester, which serve 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. When making the webbing, we have to take following characteristics in to consideration, the breaking strength, elongation, abrasion and the environment. There are mandated criteria for breaking strength and elongation of the tie down strap , 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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