Thanks John! That is useful information.
I can recall that Weir-Cove Moving & Storage, one of the main shippers for Weirton Steel, always loaded no more than 2 coils on each flatbed trailer. These were always tarped and chained. One would be south of the kingpin and the other would be located over the trailers back (8) wheels. The trailer had 2 axles with 4 tires per axle.
George