sure exceeds the pressure specified on the nameplate,
a pressure reducing station is required. If instrument
air is not available, install an oil separator/air filter in
the air inlet line. All connections must be leak free.
4 QUICK CHECK:
Before operating, check the valve as follows:
4.1 Open and close the valve, and observe the movement
of the actuator stem. The movement must be smooth
and linear.
4.2 Check for maximum stroke through change of signal
(for pneumatic positioners, 0.2 - 1.0 bar or corresponding split-range values; for IP positioners, 4-20
or 0-20 mA).
4.3 Check all air connections for leaks.
4.4 Tighten packing nut (see table 1).
NOTE: An excessively tightened gland nut can cause
excessive packing wear and can hinder the free movement of the plug stem.
4.5 Check fail-safe position. To do this, close supply pressure and observe whether the valve opens or closes
as defined.
4.6 After use at fluctuating temperatures, re-tighten all bolt
connections and check for leaks.
5 MAINTENANCE
Check valves for correct functioning at regular
intervals (at least once every 6 months) as follows.
This check can be made when installed and in
many cases without interrupting production.
If internal defects are suspected, see section
„Disassembly and Assembly of Valve“.
5.1 Examine gaskets for leaks and if necessary re-tighten
bolts (see Fig. 1).
5.2 Check bellows gasket and test connection - if present
- for external leaks.
5.3 Check valve for damage caused by corrosive residues
or corrosive vapours.
5.4 Clean valves and repaint as necessary.
Warning: To prevent a buildup of electrostatic charge
clean the actuator/valve with a damp cloth only.
5.5 Check gland nut for correct torque (see table 1)..
NOTE: An excessively tightened gland nut can cause
excessive packing wear and can hinder the free movement of the plug stem.
5.6 If possible, open and close valve and check for maximum stroke and smooth movement of the plug stem.
Irregular movement of the plug stem may indicate
internal defects.
NOTE: With graphite packing, irregular movement of
the plug stem is normal.
WARNING: Keep hands, hair, clothing, etc. away from
all moving parts. Failure to do so can lead to serious
injury.
5.7 Check all accessories for firm seating.
5.8 If possible, close supply pressure and check the failsafe position.
5.10 Check stem boot for wear.
5.11 Check actuator for leaks. To do this, spray housing,
air connections and plug stem guide with leak spray
and check for any bubble formation.
5.12 Clean plug stem.
5.13 Check air filter, if present, and if necessary replace
insert.
Note: For further information regarding service and
maintenance please contact your nearest FLOWSERVE
office.
DANGER: On actuators with aluminium cases the
actuator springs must be renewed with original spare
parts every 10 years or after 50.000 operating hours
which ever occurs first.
Torque
Thread PTFE Grafoil
M20 x 1,5 1 3
M30 x 1,5 6 15
M38 x 1,5 15 35
M45 x 1,5 17 40
Table 1