Securing plate steel on my flatbed?

A choke chain would have to be 35' long to wrap around it in traditional fashion...and nobody (outside of perhaps a specialized hauler who needs ridiculously long chains regularly) is going to carry anything like that. However, the fact that the load is wider than the trailer means that EVERY chain is effectively going to act as a choker, though.

To answer your question, though, I'd run chains across the top to at least meet the size & weight securement requirements, and then X in the front & rear to keep the plates from walking forward or rearward.

 

10 feet wide?

You are oversize.

 

He’s standing it up on edge on a low - pro step, so he can fit partials beside it.

 

I'm a little curious as to the "why" behind your method of attaching your chains. Looks as though both ends of each chain are attached to the same side of the trailer, and the binder is the only thing keeping the chains in place. If a binder works loose or fails, you'll be dragging a chain in no time. Maybe I'm not seeing the whole picture (I can't see through the plate to see what you have going on beneath it). Just seems like you pulled twice as many chains as necessary off your headache rack, and I'm left wondering what I'm missing at the very least what your reasoning might be as to why you did it this way instead of the typical "one end of the chain on one side of the trailer, over the load, other end of the chain on the other side of the trailer, with the binder located somewhere in between". Even trying to double up chains to increase WLL, you're still limited by the WLL of the binder. Like I said, confused & curious.

 

Those looks like 10’ chains. One hooked on each side. You can see the bungee holding the excess in place. I wouldn’t have spent the time with the bungees. The loose part of the chains not going anywhere