15. Start the retrieval of the device. Ensure that the retrieval tool is properly pressure-
balanced so that the device pressure has completely filled the retriever before the
plug is removed from the fitting, with back pressure ( use forced pressure
equalization as described in Step 16).
WARNING
Risk to Personnel and Equipment: If the retrieval tool is not properly balanced,
corrosive gas or liquid can spill out and cause serious injury. Before unscrewing
the plug, make sure that the tool is properly pressure balanced through forced
pressure equalization.
16. Apply forced pressure equalization through the following substeps:
a) A pump (or another sort of pressure vessel) is connected to the bleed off
valve on the retriever. Open the bleed valve and pressurize the retriever to a
pressure (minimum ≈145 psi (10 bar)) above actual pipe pressure.
b) Close the bleed valve to retain the pressure inside the retrieval tool.
Disconnect the pump from the bleed valve.
c) With the pilot body engaged onto the plug hexagon, unscrew the plug 2 full
turns in a counterclockwise direction.
d) Stop and confirm that the pressure on the retriever pressure gauge is similar
to the pipe pressure.
e) When balanced pressure is confirmed, continue to unscrew the plug from
the fitting (13 up to 15 turns).
17. When the plug has been cleared from the threads, fully expand the retriever to pull
the device through the service valve and into the retriever. If applicable, mount the
safety clamp.
18. Close both balls in the service valve and verify that both by-pass valves are closed.
19. Bleed off the pressure in the retriever by opening the bleed valve. You can use a
diversion hose to divert the media being bled off the retriever.
20. Ensure that all pressure is released from the tool. Keep the bleed valve open.
21. Unscrew the hammer nut and remove the retriever.
If the product media is liquid, be ready to collect the remaining media from the
inside of the retriever.
4.2 Installing a device
This topic covers installation of a device after the service valve is mounted on the fitting
and retaining pressure from the pipe. Consult the monitoring device user manual for
instructions on how to service or replace service valves.
Procedure
1. Replace the primary packing and the probe packing. If a guide o-ring is used,
inspect and replace it, if necessary.
User Manual Operating instructions
ROX000295904 June 2020
www.Emerson.com/Roxar 29
To Next Page
Loading...