What is a coil well on an Edscha body and why is it used?

A coil well is a recessed trough built into the floor of some Edscha body trailers, typically 100–200 mm deep, running between the wheel arches along the trailer floor. The coil well accommodates circular and cylindrical cargo — steel coils, cable drums, and paper rolls — preventing lateral rolling during transit by cradling the circular base in the recessed channel. The recessed floor lowers the cargo's centre of gravity, improving stability at highway speeds and through cornering. Not all Edscha bodies include a coil well — it is specified at the point of trailer manufacture based on the operator's primary cargo profile.