The coating with 90 Shore A polyurethane is necessary to facilitate the scrolling of cement and protect from wear the hopper sides.
The iron hopper weighs almost 2 Tons plus 250 Kg of casted polyurethane, while size are approximately 2.500 x 2.500 mm.
3 hoppers have been coated and because of their weight and dimensions it was necessary to coordinate carefully the different manufacturing phases.