Groth 7678 User Manual

Installation, Operation & Maintenance

Model 7678

End of Line Deflagration Flame Arrester

ATEX Certified

January 2, 2012

IOM-7678

Rev. A 12187

Ref. 97290

Table of Contents

CERTIFICATION

Section Page

Introduction 2

Certification 2

Integrated Temperature Sensor 2

Design & Function 2

Installation 3

Maintenance 4

Model Identification 6

Product Limited Warranty 6

Tables

Bolt torque 3 & 4

MESG tables 5

Attachments

ATEX Declaration of Conformity

Cert. # IBExU12ATEX2019 X

Drawings SCH-7678-01

INTRODUCTION

This manual is intended to provide
recommended procedures and practices for
installation, operation and maintenance of the
Groth Model 7678 end of line deflagration flame
arrester. Any standard procedures and practices
developed for a specific plant or process should
supersede this manual. Although this manual
cannot cover all possible contingencies,
following these guidelines will provide safe,
reliable deflagration flame arrester service.

The arrester shall be treated as a safety device
and must be maintained by a knowledgeable
repair technician. Carefully read and understand
this manual before installing or servicing this
product.

For information not contained in this manual,
please contact:

Groth Corporation

13650 North Promenade Blvd.

Stafford, TX 77477

281-295 6800

281-295-6999 Fax

Groth Model 7678 end of line deflagration flame
arresters are manufactured in compliance with
the ATEX Directive 94/4/EC, as confirmed by
Certificate IBExU12ATEX2019 X. This
certification covers the following sizes, materials
and limits for use.

Sizes included are all those shown on drawing
SCH-7678-01. Materials included are all
materials that satisfy the strength and pressure
ratings specified on these drawings.

These arresters are suitable for end of line

Explosion Gas Group

MESG of vapor

≥

0.036” [0.90 mm]

IIA

mixture

Operating

o

F to 140oF [-20oC to 60oC]

–4

Temperature

Maximum Allowable Burn

Time

*Temperature

Sensor

Emergency

Function

Connection

Burn Time Trigger Time

Size

2”-12”

2 Minutes 60 Second

(50-300mm)

deflagrations and short time burning.

*

Each temperature sensor with respect to connection size
has a trigger emergency function within half of the burn
time.

Must be installed with integrated temperature
sensor(s), Groth P/N 93219005 or equal.

INTEGRATED TEMPERATURE SENSORS

Flame arresters for short time burning must
be fitted with one or more integrated
temperature sensors, taking into account the
intended orientation of the flame arrester.
These arresters may be used in systems and
situations where the flow of the flammable
mixture can be stopped within one minute.

Groth model 7678 flame arresters were
tested with one Groth integrated temperature
sensor, P/N 93219005, installed on the
ignition side. All arresters are manufactured

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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

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:

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.

1. The MESG of the vapor constituent(s) is

greater than or equal to .036" (0.90 mm).

2. Normal operating temperature is between

o

-4

F (-20o C) and 140o F (60o 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.

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