Global water, fluid, thermal management and equipment protection company Pentair’s Valves & Controls division has launched a new line of heavy-duty resilient seated double-flanged butterfly valves, manufactured by China-based butterfly valve specialists Keystone Series GRF, aimed at industrial applications, including mining, that require large-diameter piping.

The latest addition to Pentair’s Keystone GR series of valves, unveiled last year, the Series GRF valves offer several key benefits, including a proprietary Pentair polymer seat for increased pressure holding capabilities and increased wear resistance, resulting in a higher performing, longer lasting and more reliable valve that delivers lower total cost of ownership.

Other advanced features include a fully elastomer-lined body, which allows for a dry shaft design, and blow-out resistant shafts to increase the safety of field personnel. Further, a standard double-flanged ductile iron body enables a stronger body connection.

“For more than 50 years, Keystone has been the valve brand that customers have counted on to deliver quality and performance that exceeds their requirements. This new series of GRF double-flanged butterfly valves, along with the rest of the GR family, is proof that Keystone valves do more than just perform – they outperform our customers’ expectations,” says Pentair Valves & Controls butterfly valves global product manager Joanne Lunsford.

Available in sizes ranging from DN600 to DB1800, the new large-diameter Series GRF is ideal for industrial water applications, such as desalination plant dams and water filtration; as well as the power, mining, oil and gas, chemicals and process industries.

Built to meet API and ISO specifications, the new Keystone Series GRF’s double-flanged body design is fully compliant with EN 593 and API 609 standards as well as Pressure Equipment Directive (97/23/EU) Module B1 + D and CE Marking.

The valve’s primary shaft sealing exceeds the pressure rating of the valves and prevents moisture penetration or leakage into the atmosphere, while secondary shaft seals provide back-up safety. The unique shaft design allows for a thin profile disc and provides minimal obstruction to flows through sizes DN1 040 to DN1 800.

A double-flanged body allows for easy installation and centring between the flanges, while an extended body neck accommodates pipe insulation. Top and bottom shaft bearings increase support and decrease friction and torque, while top bushings absorb actuator side thrust loads.

“This launch completes the GR family, which includes the GRW – wafer style – and GRL – lug style – in sizes ranging from DN50 to DN900. “Now, no matter what a customer’s application may be, Pentair’s GR family offers a reliable, high performance solution,” Lunsford added.