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This brochure provides information for selecting and specifying
packing systems for linear control valve applications. Packings are
classified as either environmental or non-environmental. Of these
two, environmental packing systems are the more effective and
reliable in linear applications where leakage levels are required to be
less than 500 parts per million (ppm) or in some cases, less than
100 ppm.
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Environmental packing systems are designed to provide less than
500 ppm service for typical control valve applications. In most
services, however, less than 100 ppm can be expected when the
packing is specified, installed and maintained correctly. These
packings generally have more restrictive application envelopes than
non-environmental packings. They can often be used, however,
beyond their environmental limits when higher leakage rates can
be tolerated.
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Environmental Packing Systems
Flowserve offers the following four standard environmental packing
systems for linear Valtek control valves. Other proven environmental
packing options may be available on request.
1. SafeGuard™
2. SureGuard XT™
3. LATTYpack Control - EC™
4. Chesterton 5800®
Each of these packing systems is capable of achieving very low
leakage control for extended periods in their standard or optional
configurations. Table 1 provides information to assist the user in
selecting the best packing system for the application in question.
This selection can be made by considering the fluid, pressure,
temperature, required options, sealing performance and stem
friction. For more packing system detail, see pages 6 through 13.
Non-Environmental Packing Systems
Flowserve offers the following three non-environmental packing
systems for linear Valtek control valves:
1. Standard V-ring
2. Graphite rib-braid
3. Square braid
Within the V-ring and braided packing systems, there are multiple
types and choices to best suit various applications, as shown in
Table 1. For more packing system detail, see pages 12 through 17.
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