摘要 |
There are disclosed two embodiments of a stuffing box for a movable stem of a valve, wherein each stuffing box includes first and second primary packing assemblies at its inner and outer ends, respectively, a third packing assembly intermediate the first and second packing assemblies and including axially spaced inner and outer packing sections between which sealant may be injected, as well as a bleed ring intermediate the first and second packing sections and surrounding the stem with small clearance, whereby purge fluid may be introduced into the small clearance for flow past the inner primary packing assembly in the event it fails.
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