Graphite packing excels in stem sealing for temperatures above 650°F. Die-formed rings are layered with sacrificial zinc or Inconel mesh to prevent extrusion. Live-loading via Belleville washers maintains packing stress during thermal expansion. Fugitive emission testing per ISO 15848-1 achieves Class A leakage rates. In fire-safe designs, graphite expands under heat to fill voids. Th... https://globalsealstech.com/