Alignment detection of ladle-lifting hook

In steel production, large overhead cranes transport ladles holding molten metal. Misalignment between the ladle rod and the crane hook can cause the contents of the ladle to splash or spill. In this study a system was developed to detect the alignment of a ladle rod relative to crane hook during the lifting process in a steel production facility. A method for alignment detection was achieved by redesigning the removable wear plates on hooks to include insulated metal contacts at the desired lifting points. Protected cables were used to connect the contact plates to a relay in a signal box. When the ladle rod touched the contact plate on both books, the circuit was closed, and a light was illuminated to inform the operator that it was safe to lift. A 1:4 scale test set-up was manufactured and tested. Testing showed that the green light was never illuminated erroneously and was always illuminated as desired unless there was an obstruction between the hook and ladle rod. A plan for upscaling the prototype to full-scale was formulated and recommendations for additional design and testing were given.