GF Piping Systems has expanded its large diameter size range for the Type 567 butterfly valve to include sizes 14-16 inches. The new size range, suitable for industrial wastewater treatment, features a double eccentric off-center design and excellent chemical compatibility, according to the company. Suitable applications include landfills where large size valves are required for drainage of underground leachate. The valve’s design features an off-center shaft that allows the disc to completely disengage from the disc seal, even when partially open, resulting in reduced seal friction for longer service life and minimal maintenance compared with non-eccentric valve styles. The double eccentric design requires only about half the torque of a traditional boot design, which decreases wear on the disc seal to further enhance product life. Other advantages of this design include easier manual operation, compatibility with smaller actuators for reduced installation cost, and better protection against pressure surges.