Knife gate valves have long proven to be a fantastic option for sewer applications. They are designed to cut through the solid media that travels through the lines, while ensuring pipe turbulence and erosion are kept to a minimum. Mueller recently announced a new addition to its knife gate valve inventory – the Henry Pratt P77 Perimeter-Seated Bi-Directional Knife Gate Valve. 

Engineered to specifically handle tough slurries and abrasive materials, the P77 meets rigorous MSS SP-81 standards and offers a range of features and benefits that make it an excellent valve for both municipal and industrial applications.

“The Pratt P77 Perimeter Seated Bi-Directional Knife Gate Valve is an industry game-changer,” says Dale Speggen, vice president of specialty valves for Mueller. “With its sealing capabilities and its ability to reduce stress on the packing chamber, the P77 ensures reliable and efficient operation.”

The P77 has ideal sealing capabilities, ensuring a drip-tight shutoff, and preventing the buildup of solids, regardless of line pressure. The valve is designed to eliminate any confusion regarding the direction of isolation, providing clarity and ease of use in demanding wastewater environments. It is designed with multiple rows of packing to reduce stress on the packing chamber, enhancing the longevity and reliability of the valve. The integrated PTFE gate guide reduces wear on the packing, preventing blockages and flow disruptions with its non-stick properties. Its rubber-seated gate delivers a secure bidirectional drip-tight seal, which enables it to withstand pressures of up to 150 psi effectively.

Featuring an EPDM perimeter cartridge seat, the P77 Knife Gate Valve resists chemicals and high temperatures while preventing leakage and protecting downstream equipment. By reducing leak paths and extending the life of the packing, this valve minimizes maintenance requirements and ensures smooth operation. Its handwheel can be easily converted to various types of operators, including hydraulic or pneumatic cylinders, bevel gears, chain wheels, electric motors, or fail-safe spring cylinder operators, by utilizing an existing cast yoke.

The heavy-duty cast stainless steel body is resistant to deflection from line loads and internal pressure, further enhancing the valve’s performance and longevity. In addition to municipal water and wastewater, it has applications across various industries, including pulp and paper, mining, and food and beverage.

“We are proud to offer this valve, which sets a new standard for performance and reliability, says Speggen. 877-436-7977; www.henrypratt.com