Bellows Stem Seal Option
Hex offers a bellows stem seal option for use on Hex instrument valves in the control and monitoring of corrosive chemicals, hazardous materials or any application where leakage and containment are primary considerations.
The bellows stem seal option can be specified on a wide range of Hex instrument valves, gauge valves, bleed valves, three and five valve manifolds and static pressure manifolds. The bellows is hydro-formed and laser-welded to the stem assembly for greater stability and longer life.
The bellows can be provided in either 316L or Monel, and the option also provides secondary sealing for greater protection than can be achieved with a single seal design. Hex Valve exercised care in maintaining compact bonnet dimensions to reduce the risk of accidental breakage or damage to the bellows and also to reduce the amount of space that would be required to install the products.
- Non-Rotating Trip (NRT) Stem: provides tight, repeatable shutoff without the galling or cross-scoring that occurs on ball type stems. The NRT conical stem tip stops rotating when it contacts the seat, so further torque turns the stem, but not the tip, preventing damage to the tip.
- Optional Seal Welding: Fillet welds covering all joined external components can be specified as an option.
- Back-Up Sealing: Secondary sealing for greater protection against leakage than provided by single seal designs. Available with o-ring or packed seal on hard seated models.
- Bellows Option Available on a Wide Selection of Models: The bellows stem seal option can be provided on Hex instrument valves, primary gauge or block valves, bleed valves, three valve manifolds and static pressure manifolds.