Even in our era of advanced technology, robotics, and air-conditioned control rooms, the operating equipment in steel mills must be rugged and sturdy to withstand exposure to heat, metal debris, and coolant chemicals.
One of the critical machines in a steel mill application is the pinch roller, which moves molten steel material between milling devices. Because such transport is critical in keeping the work moving, and requires heavy duty machinery to do what couldn’t be done safely by hand, an efficient mill needs reliable supplies to keep pinch rollers in service.
One client of US Hose Corporation (a United Flexible company), a major steel producer, was experiencing high failure rates with hydraulic hoses supplying a water-glycol solution to the pinch roll machinery. Because rubber is a flexible product often in use for fluid transfer, it was one choice for the steel mill application, but it couldn’t hold up to the heat, both in the mill’s environment and particularly in proximity to the continuous casting process that the pinch roller was feeding. The next material the steel producer tried was a metal hose, but in addition to heat fatigue, corrosion was a problem. Both materials (rubber and metal) were causing time-consuming and costly delays as failures resulted in equipment down time.
Our engineers were tasked with finding a hydraulic hose solution that could withstand the environment and provide a year or more of service (rather than failing within weeks of installation as other materials had). The particular challenges included:
- Intense heat—adjacent to molten metal exiting the caster
- Overspray from untreated water coolant
Through extensive study and testing, our engineers developed a custom fluoropolymer hose product—based on our popular Dense-Pac hose, but unique to the steel producer’s application. It features a PTFE inner core, a high density steel metal exterior braid, and a protection coating including silicone to withstand corrosion. The result is a product that provides the desired lifetime—and the required mill uptime. Efficiency mattered so much to the client that it was worth investing in the most reliable solution.
And once the steel producer had found this solution with US Hose Corporation (a United Flexible company), they started asking, Where else can we use this hose? It’s moved beyond this single urgent application into other installations at the mill because of its extreme reliability, including the other side of the caster (the steel entry point). The ladle slide gate was also experiencing hydraulic hose failure due to extreme heat—approximately 260°C (500°F)—and the interaction with the hydraulic fluid itself. Building again on Dense-Pac, the variation of the hose for this application featured a PTFE inner core, metal braided exterior, and an insulating fire sleeve as a cover. These customized versions of an already heavy-duty hose product keeps the steel mill on target, meeting their efficiency goals as they know they can rely on the components that support their milling equipment.