FLOWSERVE DURCO G4 plug valves ensure a better seal in the passage than other comparable ON/OFF valves and offer equivalent or superior emission protection compared to custom-made heavy-duty special valves. They are ideally suited for difficult applications in the chemical and process industries, for shutting off pipelines, pumps, liquid containers, reactors, and other critical applications.
The G4Z series plug valves are fire-safe, in contrast to the standard G4 and G4E series models. The G4Z-HF plug valve, for example, is intended for alkylation plants with UOP/Phillips licenses in refineries.
The fire-safe plug valves G4Z as well as G4EZ and G4EBZ are equipped with special Grafoil ring packages on the stem and Grafoil sealing sleeves on the upper valve cover, ensuring that in the event of the PTFE bushing and diaphragm being destroyed by fire, any ingress of air is limited to an insignificant level. Should the upper seal be destroyed, the Grafoil Package is held in place by a metal diaphragm.
