In an industrial plant, "sealing" covers two situations that share a goal but not a problem:
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Static seal (gasket on a flanged connection): the surfaces do not move; its task is to resist pressure, temperature, and process fluid for as long as the connection stays closed.
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Dynamic seal (packing around the stem of a valve): it must withstand the same conditions while the stem moves through it, keeping the fluid contained without losing tightness and without wearing the stem.
That extra requirement changes the logic of selection:
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For a gasket, the question is whether material and construction can withstand the service conditions.
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For a packing, resisting is only the starting point: the material must also accommodate movement. A solution chosen on static criteria alone may be adequate on a flange and still be wrong in a stuffing box. This is why the two categories cannot be approached with the same selection logic.
The braided packing range offered by Carrara includes expanded graphite braids, PTFE packings, braids made with GORE® GFO® yarns, aramid yarns for dynamic applications, glass yarn packings, and special yarns for abrasive services, organised across three lines: Performer, Premium, and Basic.
Application examples and technologies:
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Graphite packing GR8048: combines carbon fibre graphite yarn and expanded mineral graphite. It is suitable for both static services (high pressure/temperature in valves and pumps) and dynamic services (soot blowers and diathermic oil systems), thanks to continuous PAN carbon fibre yarn on the corners that protects against extrusion and wear.
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Emissions control: GR8048 minimises fugitive emissions through a treatment based on pure graphite powder and a corrosion inhibitor, while GR80SGR (also available in the OXY version for oxygen applications) is intended for the most severe, low-emission applications.
Carrara develops gaskets for flanged connections and packings for valves with this distinction in mind. Static or dynamic, the goal is the same: containment. What changes is the question the seal has to answer.