
Consolidated 2900-40 Series POSRV Maintenance Manual | 55
© 2019 Baker Hughes, a GE company. All Rights Reserved.
XXII. 2900-40 Series POSRV Options
When the pilot operated safety relief valve is not vented
directly to atmosphere, it is possible to build up backpressure
in the discharge line. This is typical in situations where several
valves manifold into a common discharge header. Should the
discharge line pressure exceed the valve inlet pressure, it
could cause the disc to lift and allow reverse flow through the
main valve. This situation can be eliminated through the use of
the Backflow Preventer.
Note: Item #23 in Figures 3 is the same Field Test Connection shown
here in Figure 42. Shuttle Base (23c) can be square or octagon
bar stock.
A.1 Disassembly Instructions
1. Remove Shuttle Plug from Shuttle Base by unscrewing
counterclockwise.
2. Remove Shuttle Ball, Tube Filter, and O-Rings and discard.
A.2 Cleaning
1. If required, clean parts to remove all rust, burrs, scale,
organic matter, and loose particles. Parts are to be free of
any oil or grease except for lubrication as specified in this
instruction.
2. Cleaning agents used shall be such that effective cleaning
is assured without injuring the surface finishes or material
properties of the part.
3. Acceptable cleaning agents include demineralized water,
nonphosphate detergent, acetone, and isopropyl alcohol.
Parts must be blown dry or wiped dry after cleaning.
4. If you are using cleaning solvents, take precautions
to protect yourself from potential danger from
breathing fumes, chemical burns, or explosion. See the
solvent’s Material Safety Data Sheet for safe handling
recommendations and equipment.
5. It is not recommended to “sand blast” internal parts as it
can reduce the dimensions of the parts.
A.3 Parts Inspection
1. Shuttle Base: Galling or excessive wear on the threads.
Check for any corrosion or pitting.
2. Shuttle Plug: Galling or excessive wear on the threads.
Check for any corrosion or pitting.
A.4 Reassembly Instructions
Lubricate O-Rings with silicone grease BHGE P/N SP505.
1. Assembly of Field Test Connection / Backflow Preventer
Assembly.
a. Insert one of the Small O-Rings into the Shuttle Base
counter bore.
b. Insert the Tube Filter into the Shuttle Base.
c. Insert Shuttle Ball inside of Tube Filter.
d. Insert the other Small O-Ring into the Shuttle Plug
counter bore. Install Larger O-Ring into groove located
on OD of Shuttle Plug.
e. Thread Shuttle Plug into Shuttle Base, wrench tighten.
Backflow
Preventer
Backflow
Preventer
Field Test
Connection
23a
23e
23b
23c
23d
23b
Figure 42: Field Test Connection /
Backflow Preventer Option
Figure 43: Backflow Preventer Option
A. Backflow Preventer
Ref. No
Part
23a
Shuttle Ball
23b
O-Ring
23c
Shuttle Base
23d
Shuttle Plug
23e
Tube Filter