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SV2 Series Safety Shut-off Valves
66
32-00029—02
Introduction and Flange Selection
Flanges are required to mount each valve and provide connection to standard NPT or BSP gas pipes. There are several available
flanges per valve body size. Flange kits designated as AB are for the 1 inch (DN25) valves while flange kits designated as CD
are for the 1 ½ and 2 inch (DN40 and DN50) valves. Each flange kit consists of 1 flange with sealing plug and 4 screws. Sealing
O-rings are shipped with each valve from the factory.
Table 13. Available Flange Kits.
Valve Sizes
Thread Type
Size
Inches / DN
Flange Kit
Valve Models
B
1 inch
(DN25)
1.0 MMBTu
(300 kW)
at 4 in w.c. pressure drop
NPT
0.50 / DN15
FLANGEABNPT050
All
0.75 / DN20
FLANGEABNPT075
1.00 / DN25
FLANGEABNPT100
1.25 / DN32
FLANGEABNPT125
BSP
0.50 / DN15
FLANGEABBSP050
0.75 / DN20
FLANGEABBSP075
1.00 / DN25
FLANGEABBSP100
1.25 / DN32
FLANGEABBSP125
C / D
1 ½ and 2 inch
(DN40 and DN50)
2.6-4.6 MMBTu
(750-1348 kW)
at 4 in w.c. pressure drop
NPT
1.00 / DN25
FLANGECDNPT100
All
1.25 / DN32
FLANGECDNPT125
1.50 / DN40
FLANGECDNPT150
2.00 / DN50
FLANGECDNPT200
BSP
1.00 / DN25
FLANGECDBSP100
1.25 / DN32
FLANGECDBSP125
1.50 / DN40
FLANGECDBSP150
2.00 / DN50
FLANGECDBSP200
Mounting Valve to Flange(s) and Piping
When initially installing the valve, the installer must first determine the overall mounting orientation, then mount the flanges to
the main gas connection pipe and finally mount the valve to the flanges and piping.
NOTES:
• Flange Installation Instructions are packed with the flanges. Reference documents 32-00028 for
1 in (DN25) valve bodies and 32-00036 for 1 ½ and 2 in (DN40 and DN50) valve bodies.
• The entire mounting and installation process is covered in detail in the valve installation
instructions, 32-00018 (packed with each valve).
The process for mounting the 1 inch (DN25) valves/flanges differs from the process for mounting the 1 ½ and 2 inch (DN40 and
DN50) valves/flanges.
• 1 inch (DN25) valve bodies have drilled and tapped holes
– The flange pressure port must be installed facing sideways (refer to Figs. 2-3) due to the mounting
hole orientations.
– To prevent rotation, it is important to support the valve while installing it into the pipe train. The
screws may then be inserted into the flanges and tightened. The recommended tightening torque is
3.4 Nm (30 in-lbf).
• 1 ½, 2 inch (DN40/50) valve bodies have embedded slots for flange retaining nuts
– The flange pressure port must be installed facing either up or down (refer to Figs. 4-6) due to the mounting hold
orientations.
– The installer must first place 4 flange retaining nuts on one side only of the valve (front or back),
from inlet to outlet, such as side A/B only referenced in
Fig. 16
or side C/D only. Then, on each
flange, they must partially install the screws and retaining nuts onto the
opposite side relative to
the nut placement in the previous step.
The installer would then slide the valve into the pipe train,
ensuring that the partially installed retaining nuts on the flange slide into their respective slots
on the valve body. The valve must be supported as necessary to ensure that it does not rotate. The
installer would then tighten the partially installed flange screws per the recommended torque of