Girth gear for ball mill, 30 m, z 162 and z 20 pinions, made with NiCrMo toothed rim on electrowelded steel frame. Welds are performed by a special controlled preheating and cooling process due to the different carbon contents and different thermal expansion of the materials welded together. Magnetic particle and ultrasonic inspections are performed to confirm the welding full penetration and to detect any possible surface micro-cracks.
Tectyl rust inhibitor is sprayed on all machined surfaces prior to packaging for sea shipment to the end customer in Tunisia.