Groth 7758A - Manual (Page 4)

The 7758A detonation flame arrester may NOT be
effective in stopping flame propagation in systems
which contain vapors with an MESG less than
0.025" [0.65 mm] or when any of the operating
conditions are exceeded.
All Groth Detonation flame arresters are bi-
directional and can be used in vertical or horizontal
piping systems.
This series of flame arresters all have 150# ANSI
flanges, or DIN/JIS flanges of equal pressure rating.
Please follow the torque guidelines listed in Table 1
for flange make-up torque.
WARNING
The flame arrester housings or adjacent piping
may have various pipe taps for pressure sensing,
temperature sensing, condensate drainage, etc.
Never connect such taps to a common line or
system as this could provide a flame bypass around
the flame arrester element.
The following guidelines should be observed at
installation:
1. Remove any flange protectors and discard all
packing material.
2. Inspect the gasket seating surface of the mating
flanges. It must be clean, flat, and free of
scratches, corrosion and tool marks.
3. Inspect the gasket; make sure that the material
is suitable for the application.
4. Lubricate all studs and nuts with an appropriate
thread lubricant. If the arrester will see high
temperature service or stainless steel fasteners
are used, select an anti-seize compound such
as moly-disulfide.
5. Center the gasket within the bolt circle.
WARNING
The lifting eye(s) on the element housing are
to be used for handling the housing only
during inspection and maintenance. DO NOT
use these eyes to lift the entire detonation
flame arrester assembly.
6. Set the arrester between its mating flanges or
nozzle. Position the lifting handles and jacking
bolts to facilitate future removal of the flame
arrester housing. Position the drain and
instrument ports to provide proper access and
function. (See Maintenance
Instructions).
Install the studs and tighten nuts hand tight.
Notes:
• When installing the Models 7758A in a
horizontal pipeline, use the lowest 1" ports to
drain condensed vapors from the housing.
Note previous warning when connecting the
drain piping.
7. Torque all fasteners to half the value listed in
Table 1 in a staggered, alternating pattern to
provide an evenly compressed gasket joint.
•
(Torque is an average value based on a nitrile
binder synthetic gasket, 1/32" thick and
lubricated threads).
8. Make up the final torque and check that no
further nut rotation occurs at the specified
torque value.
Table 1
PIPE FLANGE STUD
TORQUE CHART
Lb.Ft. (Nm)
Size Torque
8 [200] 111 [150]
10 [250] 170 [230]
12 [300] 170 [230]
WARNING
After installation, all connections must be
inspected for vapor leakage. This may be
accomplished by static test, gas detector, or
"bubble" test using a soap solution.
IOM-7758A
Ref. ID 97895
3