Groth 7678 - Manual (Page 3)

3
with a minimum of either one thermowell or
one thermocouple port, positioned to align
the thermocouple with the face of the
element. Multiple thermowells or ports may
be on one or both faces as specified by the
purchaser. Groth temperature sensors may
also be installed as specified.
If the purchaser installs an integrated
temperature sensor, it must be an ATEX
approved devise, installed so that the sensor
contacts the bottom of the thermowell or the
face of the element.
DESIGN AND FUNCTION
Groth's end of line deflagration flame arresters
are designed to prevent flame propagation in
gas piping systems which contain flammable
gas/vapor mixtures. The arrester must prevent
flame
passage under certain specified
conditions while permitting free flow of
gas/vapor through the system. Thus it protects
vulnerable equipment or components of the
system from damage due to explosive pressures
caused by gas/vapor ignition from outside of the
system. The end of line deflagration flame
arrester must be used under only those
operating conditions for which it was designed
and tested.
The flame arresters consist of two main
components: the arrester base and the flame
element housing assembly. The base serves as
the connecting interface to the piping system.
The housing retains and supports the flame
element. Both components are essential in
stopping the passage of the flame.
The flame element is comprised of small parallel
passageways aligned so that an approaching
flame front is slowed down and then quenched
before it can propagate to the protected side of
the device. All Groth flame elements utilize spiral
wound, crimped ribbon constructed of corrosion
resistant materials, to ensure the best flame
quenching performance with minimum pressure
drop. The element is supported by rigid beams,
securely welded into the housing.
Depending on the design of the system in which
it is used, the arrester bases can include
optional ports for thermocouples or pressure
monitoring devices.
See “INTEGRATED TEMPERATURE SENSORS”
These devices can activate warning or shutdown
systems if abnormal conditions are detected.
The weatherhood may be removed for in-place
maintenance of the element, or element removal
may be required for inspection/maintenance.
INSTALLATION
Operating Conditions:
Based on the testing conditions, this series of
end of line deflagration flame arresters may be
installed in systems where:
1. The MESG of the vapor constituent(s) is
greater than or equal to .036" (0.90 mm).
2. Normal operating temperature is between
-4
o
F (-20
o
C) and 140
o
F (60
o
C).
3. The tank or piping system to which the flame
arrester is to be installed must not exceed
the arrester flange size.
WARNING
The 7678 end of line deflagration flame
arrester may NOT be effective in stopping
flame propagation in systems which contain
vapors with an MESG less than 0.036" [0.90
mm] or when any of the operating conditions
are exceeded.
All Groth end of line deflagration flame arresters
are designed for vertical installation but will
function equally well in a horizontal orientation.
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.
This series of flame arresters all have 150#
ANSI flanges. Please follow the torque
guidelines listed in Table 1 for flange make-up
torque.