TOOL
USagE
Flathead screwdriver and 1/4 in. drive
•
Adjustment of Overpressure and Underpressure Shutoff (OPSO / UPSO) setting
10 mm / 3/8 in. Wrench
•
Removal and installation of the actuator screws (key 16, Figure 15)
• Removal and installation of body flange screws (key 34, Figure 15)
•
Removal and installation of the lock nut (key 31, Figure 15)
14 mm / 9/16 in. Wrench
•
Removal and installation of the external sense line 1/4 NPT connection (Figure 6)
Internal retaining ring pliers
•
Removal and installation of the VSX4 Series fastening ring (key 44, Figure 15)
Needle Nose Pliers
•
Removal and installation of Cotter Pin for VSX8 Series
Table 7.
Recommended Tools
inDiCaTiOn
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If the valve will not close
Operating fault
Check the following:
•
The shut-off pressure settings for high and low pressure values are correct.
•
The O-rings are sealing tightly.
•
The sensing line is plugged.
Remove the controller and check the following:
•
The reset latch is not stuck.
•
The state of the diaphragm assembly for wear and tear.
Or contact your local Sales Office.
If the downstream pressure in the controller decreases
External leak
Locate and seal the leak.
Or contact your local Sales Office.
If the outlet pressure in the controller is constant
- - - -
•
Bleed off the outlet side of the regulator.
•
Observe the evolution of the outlet pressure (check tightness).
If the downstream pressure in the controller increases
Internal leak
Check the following:
•
The valve plug (disk)
•
The internal interface O-ring (key 46, Figure 15)
•
The reset stem O-ring (key 29, Figure 15)
Or contact your local Sales Office.
Table 8.
VSX4 and VSX8 Series Troubleshooting
•
Refer to Figure 15 when following this procedure.Remove
the body flange screws (key 34) and the two half flanges
(key 36). Remove the controller from the body.
•
Install the sense blocking screw (key 51) and O- ring
(key 50).
•
Remove the 1/4 NPT plug from the 1/4 NPT Control line
port (Figure 6).
•
Reassemble in reverse order, ensure to follow the
steps outlined in the General Controller Reassembly
Procedures section.
•
Connect a downstream control line with an outer diameter
of 6.4 mm / 0.25 in. or larger to the 1/4 NPT Control line
port shown in Figure 6 and to the downstream system as
indicated in Figure 6.
Spring and Diaphragm replacement
•
Refer to Figure 15 when following this procedure.
Unscrew and remove the closing cap (key 3). Using a
flathead screwdriver, unscrew and remove the OPSO
adjusting screw (key 43), OPSO spring (key 41),
maximum washer (key 42).
•
Unscrew and remove the UPSO adjusting screw (key 40),
mini washer (key 103) and UPSO spring (key 38).
•
Using a 10 mm / 3/8 in. wrench, unscrew and remove
the eight spring case screws (key 16) and associated
nuts (key 12) and then remove the spring case
(key 2). For Type VSX4H or VSX8H, remove the
diaphragm support (key 32).
•
To remove the diaphragm assembly, gently grasp the
edge of the diaphragm (key 6) while at the same time
pulling the reset button (key 30) slightly, which will allow
for sliding the back plate (key 5) off of the cam (key 19).
Grasp the back plate (key 5) and unscrew the nut (key 31)
using a 10 mm / 3/8 in. wrench. Remove the diaphragm
plate (key 7) and inspect the diaphragm and replace if
necessary. The lock nut (key 31) should always be replaced.
Reassemble in reverse order, ensure to follow steps
outlined in the following section “General Controller
Reassembly Procedures.” Note that when tightening
the lock nut (key 31) onto screw (key 16), a hexagonal
recess exists at the bottom of the back plate (key 5) that
precludes the screw (key 16) from turning to allow the
lock nut (key 31) to be threaded.
general Controller reassembly Procedures
•
It is recommended that O-rings (keys 14 and 24) be
replaced before reinstalling the controller valve onto the
regulator body.
•
Before reassembly, inspect removed O-rings for damage
or wear and replace if necessary.
•
Before reassembly, apply silicone grease lubricant to the
appropriate O-rings.
•
Using graphite molybdenum, grease appropriate screws,
setting nuts and springs (keys 38, 40, 41, 43 and 103).
• Recommended torque for screws (key 16) is 6.0 N•m /
4.4 ft-lbs.
• Recommended torque for lock nut (key 31) is 3 N•m /
27 in-lbs.
• Recommended torque for the body flange screws
(key 34) is 6 N•m / 4.4 ft-lbs.
Parts Ordering
Controller that have been disassembled for repair must be
tested for proper operation before being returned to service.
The type number, pressure ranges, functional class and
date of manufacture are stamped on the nameplate.
Always provide this information when corresponding with
your local Sales Office regarding replacement parts or
technical assistance.
When ordering replacement parts, refer to the key number of
each needed part as found in the parts list.
Separate kits containing all recommended spare parts are
available. See tables on pages 14 and 16.
VSX4 and VSX8 Series
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