Wey Valve (Sistag AG)

Wey Valve, a brand of Sistag AG based in Eschenbach, Switzerland since 1956, manufactures industrial knife gate valves, butterfly valves, check valves, and water control gates for water and wastewater infrastructure. The company's distinguishing engineering feature is the Original Wey Design, which allows knife gate valves to be repacked in situ—while in service and under pressure—in a few simple steps without removing the valve body from the pipeline. The VSC model is their pneumatically operated stainless steel knife gate valve, configurable with industry-specific attachments for applications including plastics processing. Centric butterfly valves are offered in sizes from DN 80 through DN 1600, with the DN 900 version cited in wastewater treatment installations. Water control gates and sluice gates round out the product line for WWTP flow control applications. Wey Valve products have been installed at facilities including Geneva's Jet d'Eau pumping station renovation and the Schönau wastewater treatment plant in Germany. The company maintains a global presence through subsidiaries and representatives across the Americas, Europe, Asia, and Oceania, covering over 40 countries. No specific certifications were disclosed on the English-language website.