OK, here we will discuss something familiar to many truckers, ratchet straps, as you can plainly see, there are two words, ratchet and straps, and you also guessed right, the ratchet straps are assembly of ratchets and webbing, think about cam buckle straps? yeah, box truck business with straps! Relatively weak, the cam straps are most seen inside box trucks and on passenger cars. Ratchets are another story, the hardware is pretty strong, and because of it's mechanism, the ratchet can be pretty small and fairly large, you will be able to get 1''-4'' ratchets around, and the breaking strength is often as weak as a couple of hundred LBS to as strong as 16,2000 LBS, it's pretty versatile compare to all or any other truck 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 cargo straps. And these straps are not as strong because 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. The working load limit of 2' e track straps are less than other 2'' truck straps, this is due to the truck wall provides support for the load and prevent the strain from moving if stacked properly, but you still must make sure the strain in your truck are secured properly and the way to secure them work.
As per cargo securement standard, the design factor of ratchet assembly is 3:1, meaning that the breaking strength of the tie down is 3 times of the working load limit, this indicates a relatively forgiving work place, on the other hand the design factor of transport chains is 4:1, which indicates the chains will undoubtedly be better suited for tough conditions, such as for example very high/low temperature, moisture, while the aforementioned truck straps are just for normal conditions.
The truck straps usually made from polyester, which includes low elongation and less elastic, which is perfect for tie down truck load, since we don't want the strain on the truck bed to go or budge. When making tie down straps, manufacturer must follow certain guidelines and pass DOT inspection, this implies all the straps made for tie down purpose have to meet all of the requirements imposed by FMCSA(Federal Motor Carrier Safety Agency) and follow the guideline of WSTDA and ASTM.