Flowserve Valtek Mark One and Mark Two Control Valves - Manual (Page 13)

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Valtek Mark One and Mark Two Control Valves FCD VLENIM001-01-AQ - 8/14
be examined for damage. Repair and replacement of dam-
aged parts is critical to maintaining cavitation resistance.
8.2.3. ChannelStream retainers should be cleaned of debris when-
ever the valve is opened.
8.2.4. Use the following steps if the retainer must be disassembled
to clean or inspect for damage. ChannelStream retainers in
pressure classes 900 and higher cannot be disassembled
in the field. Contact your local Flowserve representative for
service options.
8.2.4.1. Carefully grind away the small bead welds located on the
assembly pins near the top of the retainer. This will loosen
the pins which hold the retainer together. Using a punch,
locate the hole in the retainer opposite the pin and drive
each pin out of the retainer.
8.2.4.2. The retainer can now be inspected for damage or cleaned.
8.2.4.3. Reassemble the retainer sleeves and reinstall the pins mak-
ing sure to leave an open hole opposite each pin so that the
pin can be driven out in the future. Apply a small (1/8 inch)
bead of weld to each pin to hold it in place.
NOTE: Do not weld more than the approved 1/8 inch. Ex-
cessive heat from the bead welds that are too large can dis-
turb critical retainer tolerances. Use an appropriate weld
rod which is compatible with the retainer material. If uncer-
tain, contact the factory.
CAUTION: To function properly, ChannelStream is always
installed flow over.
8.3. MegaStream
8.3.1. MegaStream replaces the standard Mark One retainer with
a drilled hole retainer, see Figure 8. The plug and bonnet
are typically identical to the standard Mark One design. As-
sembly and disassembly of the valve follows the standard
procedures.
8.3.2. MegaStream retainers, plugs and seats should be exam-
ined for damage when disassembled. Holes in the retainer
should be checked for worn or eroded surfaces. Check for
plugged holes in the retainer. Multi-stage MegaStream re-
tainers cannot be disassembled. Repair and replacement of
damaged parts is critical to maintaining noise control.
CAUTION: To function properly, MegaStream is always in-
stalled flow under.
8.4. Stealth
8.4.1. Stealth replaces the standard Mark One retainer with a
braised, stacked-disk retainer, see Figure 9. Several of the
parts, including the plug, seat ring and bonnet have dimen-
Figure 8
Mark One with MegaStream Trim Body Assembly
Figure 9
Mark One with Stealth Trim Body Assembly