FLSmidth says its Krebs® Technequip™ TGW series of wafer-style knife gate slurry valves have proven themselves across the globe.
The valves are designed specifically for the harsh and abrasive slurries encountered in the mineral processing and power industries, with applications ranging from cement, sand and gravel to coal, phosphate, ash and alumina.
They are designed as a space saving option for heavy-duty applications, according to the company. The long-lasting replaceable elastomer sleeves offer a sealing solution that uses the latest technology, with the valve’s operation based on its full port design, FLSmidth said. This allows the gate to be fully isolated by the sleeves from the process in the open position.
“As the gate closes, it pushes between the two sleeves, discharging a small amount of material out of the bottom of the valve,” FLSmidth said. “This prevents material build-up in the seat area ensuring full gate closure, as well as preventing damage to the gate. When the gate is in the open or closed position, there is a 100% bi-directional bubbletight seal and zero downstream leakage.”
To ensure long life, all valves are supplied with dust boots – or ‘bellows’ – as a standard feature, protecting valve stems and actuators. Hardware such as nuts, bolts, and washers, meanwhile, are zinc-plated to protect against corrosion. Each component is also individually epoxy-painted before assembly.
Several actuation options are available, including pneumatic, hydraulic, electric and bevel-gear actuators, as well as manual hand-wheel operators, the company said.
The choice of materials is vital to the valves’ performance, reliability and lifespan, according to FLSmidth. “Sleeves are constructed of dense moulded elastomer, complete with an integral stiffener ring moulded into the sleeve. They are also available in a range of different materials to suit the application,” the company said. The valve housing is ASTM A536 cast ductile coated for corrosion resistance, while the upper cavity is pre-lubricated with a silicone-based grease, to improve actuation and decrease wear.
Founded in Toronto, Canada, in 1957, Technequip was acquired by FLSmidth in 1993 and integrated into the company in 2007. With installations across the globe, the slurry valves have proven themselves worldwide with features like the fluorocarbon gate coating for reduced friction during actuation, the high strength stainless steel gate clevis and two-coat epoxy paint. The valves also contain no packing gland, as this can jam the gate, and have machined gate guides so no spacer bars are required. Various accessories are available, including solenoids, limit switches and junction boxes.