Cargo control is a normal part of life for truck drivers. Those who master the finer points tend to have an easier time than those that struggle with cargo control. It is all about physics, so truck drivers have to learn a little bit of science to be successful cargo handlers. The fundamental starting point is the fact that properly secured cargo actually becomes part of the trailer on which it is loaded.
Physics is a science that deals with energy. Physics majors understand where energy comes from, how it is stored, how it is transferred, etc. They know that in a trucking scenario, the energy stored in the freight and trailer of a flatbed rank is potential energy. That is to say that the energy has potential to move in a certain direction. This tells us that truckers have to pay attention to a number of things when tying down cargo.
Four Different Forces
Truck drivers are required to use a variety of blocks and tie-downs to prevent cargo from moving even an inch during transport. The point of what they do is to overcome four of the natural forces inherent to moving vehicles:
- Lateral Force – This is force moving forward. All of the freight on a flatbed truck possesses potential energy that makes the freight want to move forward as the truck decelerates. A truck driver must account for this lateral force with tie-downs, a headboard, blocks or any combination thereof.
- Rearward Force – This is similar to lateral force except in the opposite direction. Cargo will want to shift rearward on a trailer during acceleration as a result of this force.
- Sideways Force – Every time a tractor trailer turns right or left, the potential energy of the freight wants to move that freight to one side or the other. A truck turning left puts right-moving force on the freight and vice-versa.
- Upward Force – This is the least troublesome force for flatbed trailer loads. It is the force put on cargo by wind, road vibrations, and bumps. It wants to send freight in an upward motion.
The idea behind cargo control is to secure freight in such a way that all of these forces are overcome. In essence, tying down the freight makes it a physical part of the truck for the purposes of overcoming potential energy. For example, tie-downs deployed to combat sideways force cause the freight to move in the same direction as the trailer because that freight is now part of the trailer.
Immobilization Creates a Single Unit
It can be hard to wrap your brain around the fact that properly secured cargo becomes a physical part of the trailer on which it is loaded. But it does. Cargo immobilization crates a single unit for the purposes of energy distribution. Mytee Products, an Ohio company that specializes in cargo control for the trucking industry, says a good way to understand this is to look at welds.
It is fairly common for engineers to rely on welds when transporting certain kinds of cargo on ships. They actually weld the cargo to the ships. The welds create a permanent bond between ship deck and cargo. For all intents and purposes, the cargo is now part the ship because it is permanently affixed through the welds.
Tie-downs keeping cargo secure on a truck do the same thing. The only difference is that the tie-downs are not permanent. For the purposes of energy distribution though, the tie-downs create a single unit consisting of the trailer and all the cargo on it.