Groth 7658A Installation and operating instructions

Installation, Operation and Maintenance
7658A
Detonation
Flame Arrester
1
IOM 7658A.0
January 1997

Table of Contents
Section Page
Introduction 1
Specifications 1
Test Results 1
Design & Function 2
Installation 2
Maintenance 3
Model Identification 5
Product Limited Warranty 5
Tables
Bolt torque 3 & 4
MESG tables 5
Flow capacity table 6&7
Attachments
Certification Test Report
INTRODUCTION
This manual is intended to provide recommended
procedures and practices for installation,
operation and maintenance of the Groth Model
7658A detonation 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 detonation 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. Groth Corporation offers repair services
for all products manufactured by the Tank
Protection Division.
For information not contained in this manual,
please contact:
Groth Corporation
13650 N. Promenade Blvd
Stafford, Texas 77477
281-295-6800
281-295-6995(Fax)
SPECIFICATIONS
Detonation flame arrester-Bi-directional
Type II-contunuous burn time One hour
Minimum MESG 0.036" [0.92 mm]
Maximum system pressure 15.7 PSIA
Ambient temperature range -13° F to 140° F
Certification reports-2" through 10" size
Swacer, Inc. test report #97-2
CSA verification-File #LO 4000-5704
Certification reports-12" size
Swacer, Inc. test report #97-1
CSA verification-File #LO 4000-5704
Groth detonation flame arresters are constructed
in compliance with the United States Coast
Guard [USCG] specifications for Marine Vapor
Control Systems.
SUMMARY OF TEST RESULTS
The Groth Model 7658A detonation flame
arrester has been subjected to the following test
procedures:
Detonation testing in compliance with USCG
33 CFR Part 154 Appendix A
Endurance burn test in compliance with
USCG 33 CFR Part 154 Appendix A
Corrosion test in compliance with USCG 33
CFR Part 154 Appendix A
Flow capacity tests.
Hydrostatic and pneumatic pressure tests.
The above tests were conducted by Swacer, Inc.
and verified by the Canadian Standards
Association. The summary and conclusions of
the reports are attached.
DESIGN AND FUNCTION
Groth's detonation 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
2

in another part of the system. The detonation
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 bases and the flame
element housing assembly. The bases serve 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 insure the best
flame quenching performance with minimum
pressure drop. The element is supported by rigid
beams, securely welded into the housing to
withstand the extreme pressures of an overdriven
detonation. Each nominal size arrester can be
supplied with various diameter elements to
provide the required flow capacity.
The bases must also withstand the detonation
pressures while conveying the burning vapors
and flame front to the element. 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.
These devices can activate warning or shutdown
systems if abnormal conditions are detected.
Both bases may be equipped with large diameter
inspection/clean-out ports for in-line
maintenance of the element, or element removal
may be required for inspection/maintenance.
Note
A Type II detonation flame arrester cannot
withstand a continuous flame, and must have
a continuous flame monitoring system
capable of shutting down the vapor flow
within the time specified on the arrester
nameplate. WARNING
A detonation flame arrester may be exposed
to instantaneous pressure spikes in excess of
1000 PSI. Any instrumentation attached to
the arrester must be capable of continued
operation in this environment.
INSTALLATION
Operating Conditions:
Based on the testing conditions, this series of
detonation flame arrester may be installed in
piping systems where:
1. The MESG of the vapor constituent(s) is
greater than or equal to .036" (0.92 mm).
2. System operating pressure is less than or
equal to 15.7 PSIA (1.08 Bar).
3. Normal operating temperature is between -
13oF (-25oC) and 140oF (60o C).
4. The piping system in which the detonation
arrester is to be installed must not exceed the
arrester flange size.
WARNING
The 7658A detonation flame arrester may NOT
be effective in stopping flame propagation in
systems which contain vapors with an MESG
less than 0.036" [0.92 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.
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.
Note
When transporting the detonation arrester,
support it with the flanges in the horizontal
position. This position provides the maximum
3

support for the flame element winding. Lift the
assembly with the [2] lifting eyes attached to the
bases if applicable.
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, 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 eyes 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 nuts 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 7658A 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
2" 70 [95]
3" 70 [95]
4" 70 [95]
6" 110 [150]
8" 110 [150]
10" 170 [230]
12" 170 [230]
24" 340 [460]
WARNING
After installation, all connections must be
inspected for vapor leakage. This may be
accomplished by static test, gas detector, or
"bubble" test using Snoop or similar liquid.
MAINTENANCE
For maximum operating efficiency the element
of a flame arrester must be inspected and
maintained at regular intervals. Frequency of
inspection should be based on the experience
gained in each application. Inspection of wetted
components is recommended at least once per
year or any time that one of the following
conditions occur:
Excessive pressure drop is encountered at a
known flow rate.
A flame front is detected.
Maintenance is accomplished by removing the
element assembly for inspection and cleaning or
replacement.
CAUTION
The connecting pipeline must be free of all
hazardous or flammable vapors before inspection
procedures begin. Before disassembling arrester
consult Material Safety Data Sheets (MSDS) for all
products that the arrester was exposed to in service.
The components should be cleaned according to
MSDS procedure. Take appropriate safety
4

5
precautions regarding eye protection, skin contact &
respiration.
1. When removing the element housing for
maintenance, support the weight by
attachment to the housing handles, or lifting
eyes, and proceed as follows.
WARNING
The lifting eyes 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.
2. Loosen the hex nuts and remove only those
studs or tie rods necessary to withdraw the
housing.
3. On the remaining studs, loosen the holding
nuts and use the spreader nuts to separate the
base halves from the housing. Use spacer
blocks or spreader tools, if necessary, to
safely secure the base halves so the housing
is free for removal. The Spacers on two
studs will support the housing.
CAUTION
In a horizontal line, the flame bank
assembly should be supported before
removing the studs. Use structures and
equipment suitable for supporting the
components weight. The weight is noted
on the drawing later in this manual.
4. Remove the housing assembly for inspection.
The flame element and supporting grids shall
be visually inspected for damage or corrosion
build-up from both sides. If the flame
element appears to be damaged, it should be
replaced immediately with a new one.
5. Verify that the element openings are not
obstructed by viewing a light source through
the element passages. If the flame element is
dirty it can be cleaned by one of the
following methods:
Compressed air.
High pressure steam or water purge.
Solvent wash followed by compressed air.
WARNING:
Never try to clean the element by inserting
a sharp tool or probe into the orifices. Any
damage to the integrity of these passages
can render the flame arrester ineffective.
6. Inspect the sealing gasket for damage and
replace if necessary.
7. Reassemble the housing, bases and gaskets.
The support spacers will position the housing
on the base centerline. Insert the studs and
torque all fasteners to half the value listed in
Table 2 in a staggered, alternating pattern to
provide an evenly compressed gasket joint.
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.
8. Make up the final torque and check that no
further nut rotation occurs at the specified
torque value. The torque values are based on
original gaskets supplied by Groth
Corporation.
Table 2
HOUSING STUD TORQUE CHART
Lb.Ft. (Nm)
STUD SIZE TORQUE
3/4" 70 [95]
7/8" 110 [150]
1" 170 [230]
1 1/8" 240 [330]
1 1/4" 340 [460]
1 3/8" 460 [620]
1 1/2" 540 [730]

The table below is a partial list of vapors for which the MESG has been measured and found to be greater than or equal to
0.036" [0.92 mm]. If your system contains a gas not listed in the table, please consult the factory.
Chemical Compound MESG*
(mm) MESG (Inches)
acetone 1.02 0.040
acetonitrile 1.50 0.059
ammonia 3.17 0.125
amyl acetate 0.99 0.039
butane 0.98 0.039
butyl acetate 1.02 0.040
butyl alcohol 0.94 0.037
carbon monoxide 0.94 0.037
cyclohexane 0.94 0.037
decane 1.02 0.040
ethane 0.91 0.036
ethyl acetate 0.99 0.039
ethyl nitrite 0.96 0.038
heptane 0.91 0.036
hexane 0.93 0.037
isobutyl alcohol 0.96 0.038
Chemical Compound MESG*
(mm) MESG (Inches)
isooctane 1.04 0.041
isopentane 0.98 0.039
isopropyl alcohol 0.99 0.039
methane 1.14 0.045
methyl acetate 0.99 0.039
methyl alcohol 0.92 0.036
methyl ethyl ketone 0.92 0.036
methyl isobutyl ketone 0.98 0.039
octane 0.94 0.037
pentane 0.93 0.037
propane 0.92 0.036
propyl acetate 1.04 0.041
propylene 0.91 0.036
vinyl acetate 0.94 0.037
vinyl chloride 0.99 0.039
*Corrected MESG (mm), 100KpA, 20°C
MODEL NUMBER IDENTIFICATION
MODEL#

7658A
NOMINAL
SIZE

02"
Thru
12"
ELEMENT
SIZE

05"
Thru
24"
MATERIAL

Flame Element Winding
Body Material
3 = Carbon Steel
5 = 316 SS
Z = Special
OPTIONS

O = No Options
Z = Special
F = 150# A.N.S.I.
Flange
Z = Special Flanges
NOTES Include model number when ordering.
For special options, consult factory
EXAMPLE: 7658A - 02 - 05 - 35 - FO
Indicates a 2" Model 7658A with 5" Element Size, Carbon Steel Body, 316 SS Flame Winding, 150# Flanged Outlet, and no options
PRODUCT LIMITED WARRANTY
A. Seller warrants that products which are manufactured by Seller, are
manufactured in accordance with published specifications and free
from defects in materials and/or workmanship for a period of (12)
twelve months. Seller, at its option, will repair or replace any
products returned intact to the factory, transportation charges prepaid,
which Seller, upon inspection, shall determine to be defective in
material and/or workmanship. The foregoing shall constitute the sole
remedy for any breach of Seller's warranty.
B. THERE ARE NO UNDERSTANDINGS, AGREEMENTS,
REPRESENTATIONS, OR WARRANTIES, EXPRESS OR
IMPLIED, (INCLUDING MERCHANTABILITY OR FITNESS
FOR A PARTICULAR PURPOSE REGARDING PRODUCTS )
UNLESS SPECIFIED IN THE SALES CONTRACT. THIS
CONTRACT STATES THE ENTIRE OBLIGATION OF SELLER.
Seller makes no warranties, either express or implied, except as
provided herein, including without limitation thereof, warranties as to
marketability, merchantability, for a particular purpose or use, or
against infringement of any patent of products. In no event shall
Seller be liable for any direct, incidental or consequential damages of
any nature, or losses or expenses resulting from any defective new
product or the use of any such product, including any damages for
loss of time, inconvenience, or loss of use of any such product.
C. The original Manufacturer shall be solely responsible for the design,
development, supply, production, and performance of its products
hereunder, and the protection of its trade name or names, if any. It
assumes no responsibility, for products modified or changed in any
way by its agent or customer. Any such modifications or changes to
products sold by Seller hereunder shall make the product limited
warranty null and void.
D. The Manufacturer shall be under no obligation to manufacture, sell,
or supply, or to continue to manufacture, sell or supply any of the
Products.
6