Flowserve NT3000 Series - Manual (Page 11)

11
NT 3000 Series Electro-Pneumatic Transducer Module FCD VLAIM0047-00 - 09/04
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Disassembly and Reassembly of the
Transducer Pressure Regulator
To disassemble and reassemble the NT 3000 module, refer to Figure 8,
and proceed as follows:
1. Disconnect air supply pressure to the positioner.
2. Remove the regulator setscrew (40) from the pressure regulator
cover (38).
c WARNING: The pressure regulator has an internal spring that
is preloaded. Removing the setscrew relieves this preload.
This must be done before the pressure regulator cover is
removed; otherwise personal injury may occur.
3. Remove the pressure gauge (41).
4. Remove the pressure regulator cover (38) by evenly removing its
two mounting screws (39). The pressure regulator preload will be
further reduced as these screws are removed. If vented model is
used, remove the regulator cover gasket.
5. Remove the regulator spring button (37), the regulator spring (36),
and diaphragm retainer (35).
6. Gently remove the regulator diaphragm assembly (assembly
comprising items 31, 32, 33, and 34).
7. Using a 7 ⁄
16
-inch socket wrench, remove the poppet guide screw
(30), its O-ring (29), the regulator poppet (28), and the poppet
spring (27).
8. Before reassembly, clean the regulator cavity. Replace or clean
necessary parts before reassembly.
9. To reassemble, place the poppet spring (27) into the housing cavity.
Place the poppet guide O-ring (29) on the poppet guide screw (30)
and insert the regulator poppet (28) through the bottom of the
guide screw. Screw the guide screw into the housing being careful
not to overtighten. A maximum torque of 5 to 6 inch-pounds is
sufficient. Make sure the poppet is free to move up and down and
has spring load.
10. Gently push the diaphragm assembly (assembly comprising items
31, 32, 33, and 34) into the bore.
11. Install the regulator spring (36) and the diaphragm retainer (35)
in the bore and then place the regulator spring button (37) on the
spring. Place a small amount of thread locking compound (Loctite
222 or equivalent) on the regulator cover screws (39) and tightly
secure the pressure regulator cover (38). If vented model is used,
make sure the regulator cover gasket is installed.
12. Place a small amount of thread sealant compound on the threads of
the pressure gauge (41) and tightly thread it into the housing.
13. Apply a small amount of thread locking compound (Loctite 222
or equivalent) on the regulator setscrew (40) and install it into the
regulator cover (38).
14. Adjust setpoint of the pressure regulator by following the instruc-
tions as outlined in the “Adjusting Pressure Regulator Output”
section of this manual.
15. Reconnect the air supply to the positioner.