Troubleshooting challenge: is heat causing these cylinders to move out of sync?
In this month’s Troubleshooting Challenge, we explore the extreme environment of a steel producer that modified an electric arc furnace to incorporate a retractable hood over the conveyor, which feeds scrap metal into the melt pot. Despite this innovation, the conveyor would occasionally jam or require maintenance, leading to disruptions in operations.
A pair of hydraulic cylinders were installed on the retracting hood to enable maintenance. These cylinders needed to extend and retract simultaneously, as they were mounted on opposite sides of the hood. The entire area around the furnace and hood was extremely hot. Redundant directional control valves were also added for emergency situations. Either a manually operated valve or a solenoid-operated valve stand could be used to control the movement of the cylinders. To protect them from the heat, the valves were mounted 30 feet away from the cylinders. Additionally, a spool-type flow divider was installed near the cylinders to ensure synchronized movement.
After a prolonged shutdown, the cylinders began to bind and failed to move in sync. Even after replacing the flow divider, the hood still bound, regardless of whether the manual or solenoid-operated valve was used.
Can you identify the problem? Feel free to send your responses directly to Robert Sheaf. The solution to our October 2024 Troubleshooting Challenge will be revealed in mid-November.
You can also review previous Troubleshooting Challenge.