Consolidated 2700 Series Safety Valve Instruction Manual
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© 2022 Baker Hughes Company. All rights reserved.
when the valve is installed on the horizontal
section of a header that is preceded by an upward
section.
2. Safety valves should not be installed closer than
eight to ten pipe diameters either upstream or
downstream from a diverging, or a converging,
“Y”.
3. In cases where a piping configuration renders
the above two recommendations impractical, or
impossible, the downstream corner of the header
nozzle inlet should be rounded to a greater extent
than the upstream corner. The header nozzle
entrance should be rounded so the radius at the
downstream corner will be equal to a minimum
of one-fourth of the nozzle diameter. The radius
should be reduced gradually, leaving only a small
portion of the upstream corner with a smaller
radius. (See Figure 5.)
4. Safety valves should never be installed, in a
steam line, in a position directly opposite to a
branch line.
Excessive line vibrations are known to produce shifts
in safety valve set pressures. Vibrations may possibly
introduce chatter, causing damage to the valve and
reducing its capacity. Vibration also contributes to
increased incidents of seat leakage. Considerations
should be given to eliminating this problem prior to
installing the valve on the unit.
Steam flowing vertically out of a discharge elbow
produces a downward reaction on the elbow. Effects
of reaction force, vibration, and seismic loads, on all
valve components and discharge piping, should be
considered when designing the valve system. Refer
to ANSI B.31.1, Non-Mandatory Appendix II, Baker
Hughes Product Information Sheet SV/PI-15, and
Baker Hughes Bulletin SV-5 for further information.
SECTION A-A
A
A
DRAIN
FABRICATED
DRIP PAN
SHOWN
YOKE VENT
SCHEDULE 40 PIPE
UNION
AS CLOSE
POSSIBLE
ANCHOR DISCHARGE PIPING
SOLIDLY TO BUILDING STRUCTURE
Figure 5: Valve Installation
XI. Recommended Installation Practices (Cont.)
Table 2: 2700 Yoke Vent Sizes
Orifice
Designation
Yoke Vent Size (NPT)
in.
mm
1
.50
12.7
2
.50
12.7
3
.50
12.7
5
1
.75
19.0
4
1
.75
19.0
6
1.00
25.4
7Q
1.00
25.4
1. #5 is a smaller orifice than #4