Research Control Valve
Grafoil Packing Installation
Grafoil packing is available in preformed rings to fit standard
packing cavities for all Research Control Valves. For higher
temperature applications, Grafoil has the physical properties
to provide sealing at temperatures greater than the upper
limits of standard PTFE or Kalrez. If the application is quick
opening (on-off) and Grafoil packing is used, the standard
actuator will work with higher operating pressure. If the
application is to provide proportional control, a positioner
should be used to overcome additional drag or hysteresis.
Grafoil packing has a propensity to increase the friction on
the trim.
1. Grafoil can be installed in the bonnet over a dummy trim
as shown in Figure 1.
Figure 1:
2. Fill the cavity with the Grafoil rings, tamping into the
cavity with a packing tool or piece of appropriate size
copper tubing as shown in Figure 2, until cavity is full with
a couple threads showing.
3. Screw gland in and tighten to compress packing. Remove
gland and blow or pick out any small pieces that may be
in the threads. See Figure 3.
Figure 3:
4. Replace gland nger tight and remove dummy stem
Figure 4 and replace with new innervalve and stem.
Tighten packing gland and test seal at nal assembly the
same as with chevron ring packing.
Figure 2:
RCV-UM-01083-EN-01 (August 2014)
Figure 4:
Installation Manual
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