description of 12m, 15m  Electric Concrete placing boom Specifications 12 meters 15 meters Radius of gyration (m) 13.5 16.5 The big arm radius 11.8 14.8 The height of the placing boom (m) 4 4 Diameter of conveying pipe (mm) 125 125 Delivery pipe straight pipe wall thickness 4.5 4.5 Bend pipe wall thickness 6 6 Radius