Emerson Enardo DFA Series User manual

Figure 1. Typical Enardo DFA Series Detonation Flame Arrestor
Enardo DFA Series Detonation Flame
Arrestor (USCG/ATEX Approved)
WARNING
!
Failure to follow these instructions or
to properly install and maintain this
equipment could result in an explosion,
re and/or chemical contamination
causing property damage and personal
injury or death.
Fisher™ detonation ame arrestor must
be installed, operated and maintained
in accordance with federal, state and
local codes, rules and regulations and
Emerson Process Management Regulator
Technologies Tulsa, LLC instructions.
Failure to correct trouble could result in
a hazardous condition. Call a qualied
service person to service the unit.
Installation, operation and maintenance
procedures performed by unqualied
person may result in improper
adjustment and unsafe operation. Either
condition may result in equipment
damage or personal injury. Only a
qualied person shall install or service
the ame arrestor.
Introduction
Scope of the Manual
This Instruction Manual provides instructions for
installation, startup, maintenance and parts ordering
information for the Enardo DFA Series detonation
ame arrestor.
Product Description
The Enardo DFA Series detonation ame arrestor
represents the best value in ame arrestor protection.
The detonation ame arrestor provides protection
against ame propagation in piping systems that are
manifolded or have long run-up distances. These are
typically used for extended pipe length or multiple pipe
bend congurations to stop high pressures and ame
velocities with detonations and overdriven detonations.
It also stops conned and unconned, low and high
pressure deagration. The design is unique in the ability
to provide large ame channels which requires less
frequent maintenance and greater ease in cleaning
when service is required, translating to less down time.
Enardo DFA Series detonation ame arrestors are
bi-directional and proven to stop an ignited ammable
Table of Contents
Introduction ..................................................................1
Specifications .............................................................. 2
Principle of Operation .................................................. 4
Factors Affecting Flame Arrestor Performance ............ 4
Installation ................................................................... 6
Maintenance ................................................................ 7
Recommended Spare Parts ...................................... 11
Parts Ordering ........................................................... 11
Instruction Manual
D103810X012
January 2019
Enardo DFA Series
Outside North America Only

Specications
The Specications table lists the specications for the detonation ame arrestors. Some, or all, of the following
information is stamped on the nameplate attached to the arrestor: model number, ange size and rating, maximum initial
operating pressure, EN number (European Standard), EU type examination certicate, notied body number, gas group,
date of manufacture and serial number; other identication and customer tag number are optional.
Available Constructions
See Table 1 and Figure 3
Gas Group
D (IIA), C (IIB3) and B(IIC)
Flange Sizes and Rating
1 to 24 in. / 50 to 600 mm
CL150
Housing Size
4 to 48 in. / 100 to 1200 mm
Maximum Experimental Safe Gap (MESG)
See Table 2
Maximum Initial Operating Pressure(1)
See Table 3
Maximum Ambient Air Temperature
140°F / 60°C
Temperature Rating of Gasket(1)
Fiber Gaskets (standard): 450°F / 232°C
Graphite/Metal (optional): 1600°F / 870°C
Burning Rating
See Table 3
Housing Material
Carbon steel, 304 Stainless steel,
316 Stainless steel and Hastelloy®(2)
Element Material
304 Stainless steel, 316 Stainless steel
and Hastelloy®(2)
Certication(3)
EN 12874 ATEX Certied(4)(5)
U.S. Coast Guard (USCG) Approved(4)(5)
1. The pressure/temperature limits in this Instruction Manual and any applicable standard or code limitation should not be exceeded.
2. Hastelloy® housings and element material are not USCG approved.
3. Not all models are available with USCG and ATEX certications. Contact your local Sales Ofce for more information.
4. USCG and ATEX approval report(s) are available upon request.
5. Flow test data available upon request.
Hastelloy® is a mark owned by Haynes International, Inc.
Table 1. Enardo DFA Series Detonation Flame Arrestor Available Construction (USCG/ATEX Approved)(1)
MODEL(2) FLANGE SIZE HOUSING SIZE USCG ATEX
In. mm In. mm D C B IIA IIB3
Enardo DFA-0401 125 4100
Enardo DFA-0602(3) 250 6150  
Enardo DFA-0802 250 8200  
Enardo DFA-0803 375 8200    
Enardo DFA-1004 4100 10 250    
Enardo DFA-1206 6150 12 300    
Enardo DFA-1608 8200 16 400    
Enardo DFA-2010 10 250 20 500    
Enardo DFA-2412 12 300 24 600    
Enardo DFA-2814 14 350 28 700    
Enardo DFA-3016 16 400 30 750    
Enardo DFA-3418 18 450 34 850    
Enardo DFA-3620 20 500 36 900    
Enardo DFA-4824(3) 24 600 48 1200 
1. Not all models are available with USCG and ATEX certifications. Contact your local Sales Office for more information.
2. Includes eccentric construction.
3. Eccentric construction not USCG or ATEX certified.
2
Enardo DFA Series
Outside North America Only

Figure 2. Cut-away view of Enardo DFA Series Detonation Flame Arrestor
Figure 3. Enardo DFA Series Detonation Flame Arrestor Available Constructions and Model Numbering System
/ - -
Detonation
Flame
Arrestor
Housing
Size
Connection
Size
NEC
Gas
Group
Housing
Material
Element
Material
Connection
Type
Options
Enardo DFA =
Concentric
Enardo DFAE =
Eccentric
04 = 4 in.
through
48 = 48 in.
01 = 1 in.
through
24 = 24 in.
D (IIA)
C (IIB3)
B (IIC)
C = Carbon steel
4 = 304 SST
6 = 316 SST
H = Hastelloy®(1)
4 = 304 SST
6 = 316 SST
H = Hastelloy®(2)
F = Flat face
flange
R = Raised face
flange
1 = Drain Plug
2 = Pressure Tap
3 = Temperature Probe Tap
4 = Miscellaneous
5 = Protective coating
6 = Special feature
Note: Not all models are available with USCG and ATEX certifications. Contact your local Sales Office for more information.
Hastelloy® is a mark owned by Haynes International, Inc.
1. Hastelloy® housings are not USCG approved.
2. Hastelloy® element material is not USCG approved.
HAZARDOUS LOCATIONS
Figure 4. Product Identification and Marking for ATEX Units
Markings
Nameplate Information
A nameplate will be attached to the arrestor and will
contain the following information:
• Model Number: Ex. DFA 1206/D (see model
information above)
• Flange Size and Rating: Ex. 6 in. CL150
• Maximum Initial Operating Pressure, PO
• EN Number: Ex. ISO EN 16852 (if applicable) or
EN 12874
• EU Type Examination Certificate (if applicable)
• Notified Body Number (if applicable): Ex. 0518
• Gas Group: Ex. IIA or IIB3, D, C
• Date of Manufacture
• Serial Number
• Other Identification (Optional)
• Customer Tag Number (Optional)
3
Enardo DFA Series
Outside North America Only

vapor mixture approaching from either direction that can
be travelling at subsonic or supersonic velocities. The
patented element offers maximum ow to pressure drop
characteristics enhancing the value of the ame arrestor
in any system.
The Enardo DFA Series is designed with anged
connections, the arrestor provides the option of the
removal of the ame cell element for easy cleaning and
replacement without disconnecting the pipe connection.
Principle of Operation
Detonation ame arrestor prevents ame propagation
as it enters the exposed side of the unit to the protected
side by absorbing and dissipating heat using spiral wound
crimped ribbon ame cells. This detonation ame arrestor
utilizes an element assembly that dampens the high
velocities and pressures associated with deagration and
detonations while quenching the ame front. These cells
allow maximum ow with maximum protection.
Detonation ame arrestor has the heat capacity and
structural design to withstand all dynamic conditions of
ame propagation and still stop the ame. Detonation
ame arrestor is used when the ame can be in any of the
detonation states.
Limits of Use for Detonation/Deagration
Flame Arrestors:
• The following vapors are not within the scope of the
products covered by this IOM:
- Explosive mixtures of vapors and gases, which tend
to self-decompose (e.g. Acetylene) or which are
chemically unstable
- Carbon Disulphide, due to its special properties;
- Mixtures other than gas-air or vapor-air mixtures
(e.g. higher oxygen-nitrogen ratio, chlorine as
oxidant, etc.)
• Minimum distance between flame arrestor connection
and a restriction on the protected side is 10 L/D, but
not less than 3 m.
• Arrestors shall only be installed into piping with a
nominal size that is smaller than or equal to the
nominal size of the flame arrestor connection.
Factors A󰀨ecting Flame
Arrestor Performance
Gas Group
WARNING
!
Methanol is classied as a Group-D (IIA)
vapor. However, our lab tests indicate
that methanol exhibits characteristics
unlike other Group-D (IIA) vapors
under certain conditions. We therefore
recommend that an arrestor rated for
Group-C (IIB3) vapors be specied for
methanol service.
Table 2. Maximum Experimental Safe Gap (MESG)
NATIONAL ELECTRIC
CODE (NEC)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION (IEC)
GROUP
MESG
TEST GAS LIST
In. mm
Group D Group IIA 0.035 >0.90 Propane
Group C Group IIB3 0.026 ≥0.65 Ethylene
Group B Group IIC 0.020 <0.50 Hydrogen
Table 3. Detonation Arrestor Size Ranges and Rating, Maximum Initial Pressure and Burn Rating
DETONATION
FLAME ARRESTOR
MODEL
DETONATION
FLAME ARRESTOR
SIZE RANGE GAS GROUP
MAXIMUM INITIAL
PRESSURE DETONATION
RATING
BURN RATING
In. mm psia bar a ATEX (EN 12874) USCG
Enardo DFA***/D 2 to 12 50 to 300 D (IIA) 22.7 1.56 Unstable Stabilized Type 1 (2 hours)
Enardo DFA***/D 14 to 20 350 to 500 D (IIA) 20.7 1.43 Unstable Stabilized Type 1 (2 hours)
Enardo DFA***/D 24 600 D (IIA) 16.0 1.1 Unstable N/A Type 2 (15 minutes)
Enardo DFAE***/D 2 to 20 50 to 500 D (IIA) 20.7 1.43 Unstable 1 minute Type 2 (15 minutes)
Enardo DFA***/C 2 to 20 50 to 500 C (IIB3) 20.7 1.43 Unstable Stabilized Type 1 (2 hours)
Enardo DFAE***/C 2 to 20 50 to 500 C (IIB3) 20.7 1.43 Unstable 1 minute Type 2 (15 minutes)
4
Enardo DFA Series
Outside North America Only

The type of gas in the system determines its gas
grouping and therefore predetermines the type of
arrestor element required. The element must be
designed to accommodate the specic gas group that
could possibly ignite and propagate in the system. The
more explosive gases require the ame cell to absorb
the heat more quickly and efciently. The International
Electrotechnical Commission (IEC) groups gases
and vapors into Groups IIA through IIC categories
depending on a number of factors including the
Maximum Experimental Safe Gap (MESG) of the gas.
The National Electrical Code (NEC) groups gases into
A, B, C, D and G.M. categories.
Maximum Experimental Safe Gap (MESG)
WARNING
!
Verify that the detonation ame arrestor
being installed has the appropriate gas
group rating for your process. This
information is included in the nameplate
attached to the element housing. Do not
remove or alter this nameplate.
The Maximum Experimetal Safe Gap (MESG) is the
measurement of the maximum gap between two
equatorial anges on a metal sphere that prevents a
ame from being transmitted from the sphere to the
surrounding ammable mixture. MESG is dependent
on gas composition. The stoichiometric mixture (the
ideal air/fuel ratio for the most efcient combustion)
is used to determine the minimum MESG for a given
gas. See Table 2 for MESG information.
Turbulence in Piping System
Elbows, tees, pipe expansions and/or contractions,
spiral wound vapor hoses, valves, orice plates
and similar devices will contribute to turbulent ow.
Turbulent ow enhances mixing of the combustible
gases, greatly increasing the combustion intensity.
This can result in increased ame speeds, higher
ame temperatures and higher ame front pressures
than would occur in normal ow conditions. The
likelihood for developing detonations via Deagration
to Detonation Transition (DDT) is enhanced by
turbulent ow conditions.
Pipe Length
Extended lengths of pipe allow the ame to advance
into more severe states of ame propagation such
as high pressure deagration and detonations.
Enardo Detonation Flame Arrestors are not limited by
pipe length.
Flow Restrictions at Protected Side of
the Arrestor; Pressure Piling
When ame propagation occurs, unburned and
pressurized ammable vapors are forced through the
detonation ame arrestor into the protected (cold)
side piping. Restrictions close to the protected (cold)
side of the arrestor will restrict the passage of the
unburned ammable vapors causing pressurization to
occur inside the crimped passages of the detonation
ame arrestor element assembly. This pressurization
can result in ame passage through the arrestor to the
protected side during a ame propagation event.
WARNING
!
For maximum safety, avoid bends
and ow obstructions within 10 pipe
diameters but not less than 3 meters
on the protected (cold) side of the
detonation ame arrestor.
Maximum Initial Operating Pressure and
Fundamental Burning Velocity
The Maximum Initial Operating Pressure of the
detonation arrestor is indicated on the product
nameplate in absolute pressure units. This is the
maximum allowable pressure that is allowed at the
instant the owing velocity of the process vapors drops
to a value to or less than the fundamental burning
velocity of that particular ammable vapor stream.
When the owing velocity drops to this level, any ame
in the system can propagate back toward the fuel
source. High pressure deagrations and detonations
can occur more easily at higher system operating
pressures than at pressures near atmospheric.
Elevated pressures compress the system vapors
and can cause the ame propagation to become
more intense.
5
Enardo DFA Series
Outside North America Only

WARNING
!
If ame propagation occurs when the
system pressure is higher than the
Maximum Initial Operating Pressure, the
ame arrestor could be ine󰀨ective in
stopping the ame propagation.
Detonation State
Unstable (overdriven) detonations exist during a
deagration to detonation transition (DDT) before a
stable detonation is reached. An unstable detonation is
the most severe condition where pressure and velocity
are at maximum values. Detonation arrestors rated for
unstable detonations may be placed in any location in
a piping system, provided installation is in accordance
with all sections of this manual.
Stabilized Burning
Refer to Table 3 and 6 for stabilized burning limitations
for the Detonation Flame Arrestors covered within the
scope of this document.
WARNING
!
Unlimited burning should not be allowed
in any flame arrestor, regardless of
its rating. In installations where there
is a potential for stabilized burning, it
is recommended that a temperature
sensor, alarm and shutdown system
be installed. Stabilized burning after
ignition creates additional hazards
in applications where there could be
a continuous flow of the flammable
mixture towards the unprotected side
of the flame arrestor. An overheated
Detonation Flame Arrestor will fail and
allow flame propagation to move into the
protected side of the process.
WARNING
!
Scorched, discolored paint or discolored
metal on unprotected (hot) side end
section and/or adjacent piping is possible
indication of a stabilized flame inside
the Detonation Flame Arrestor. This is
an abnormal condition that must be
corrected. Do not operate any system
where indications of stabilized burning
are observed. Effective corrective
measures must be taken to correct this
condition. Any Detonation Flame Arrestor
with indications of stabilized burning
must be removed from service and
thoroughly inspected by personnel with
appropriate training and qualifications.
WARNING
!
Temperature sensors must be used
with flame arrestors having 1 minute
ATEX burn ratings. Never disconnect or
remove these devices.
Installation
WARNING
!
Always make sure that the system is
at atmospheric pressure and there is
no ignitable gas that could ash when
either installing or maintaining the unit.
Connection
Enardo DFA Series are normally provided with CL150
raised or at faced anges. Other anges such as CL300
are sometimes provided on special request. Make sure
the companion anges installed in adjacent piping match
the anges on the detonation ame arrestor.
Standard compressed ber gaskets that withstands
temperatures of 450°F / 232°C or higher are normally
used, but other materials of equal or higher temperature
capability may be used at the customer’s discretion.
For proper torquing of the detonation arrestor to the
process piping, please refer to Tables 6, 7 and 8.
Positioning
CAUTION
The detonation ame arrestor is
tted with lugs for lifting the element
assembly during servicing operations.
These lugs are not intended for lifting
the entire unit during installation.
Damage to the detonation ame arrestor
may result from improper lifting. The
unit should be lifted using appropriately
rated Nylon (PA) straps rigged on the
outside of the tension studs. Detonation
ame arrestors tted with temperature
sensors are directional dependant.
The sensor must be located on the
unprotected side of the arrestor.
6
Enardo DFA Series
Outside North America Only

The arrestor should be positioned such that the entire
arrestor is accessible for removal. Install the unit
such that the ow arrow located on the unit points in
the direction travelling with the product ow. Models
that have drain plugs are designed for horizontal
installation and should be installed with the drain plugs
aligned at the bottom of the unit. Models that have
pressure taps are designed to allow pressure gauges
to be installed on both sides of the ame cell assembly
to determine blockage. The pressure taps should
be aligned at the top to allow easy viewing of the
gauges. Units that are equipped with optional internal
cleaning systems should be connected to a source of
cleaning media such as water, steam or other suitable
solvent. Observe recommended installation practice as
detailed bends and/or ow obstruction section.
Flow Direction
The Enardo DFA Series is not bi-directional when
temperature sensors are required unless a sensor
is installed on both sides of the arrestor element
assembly. However, detonation arrestors are rated
for stabilized burning and bi-directional. All arrestors
covered in this manual can be installed either vertically
or horizontally. Consideration should be given to non-
symmetrical assemblies that include features such
as clean-out ports, temperature monitoring device or
other options that might have a preferred installation
direction to suit the needs of the customer.
Piping Expansions and
Reductions Adjacent to Detonation
Flame Arrestor
WARNING
!
No instrument, tubing or other device
whatsoever shall circumvent the
detonation ame arrestor in such a
manner to allow a ame path to exist
around the ame element of the arrestor.
When instrumentation is installed in
such a manner that it creates a path
circumventing the ame element of an
arrestor, measures must be taken to
prevent passage of ame through the
instrumentation device and/or system.
Instrumentation must be capable
of withstanding the maximum and
minimum pressures and temperatures to
which the device may be exposed and at
a minimum be capable of withstanding
a hydrostatic pressure test of 350 psig /
24 bar.
The Enardo DFA Series detonation ame arrestor may
be installed in any vapor control line that is smaller
than or equal to the nominal pipe diameter of the
arrestor’s connection anges. When it is necessary to
increase the diameter of the piping on the downstream
side (unprotected) of the detonation ame arrestor,
a length of pipe at least 120 pipe diameters must be
installed between the detonation ame arrestor and
the expansion. A pipe diameter is considered as the
inside diameter of pipe having a nominal size equal to
the detonation ame arrestor’s connecting anges.
Maintenance
Detonation Flame Arrestor Element
Assembly Cleaning
1. Keep the element openings clean to prevent
loss of efciency in absorbing heat. Remove the
element assembly and clean the elements to
prevent the clogging of particulates and other
contaminants on the openings. Clean the element
with a suitable cleaning media (solvent, soap,
water or steam) then blow dry using compressed
air. Be careful not to damage or dent the cell
openings as this would hamper the effectiveness
of the unit. Do not clean the arrestor elements by
rodding with wire or other hard objects to remove
blockages. Cleaning the elements with wire or
other hard objects could damage the elements and
seriously impair the arrestor’s performance. If the
arrestor element cannot be cleaned satisfactorily,
replace it.
2. For best cleaning results, use a high pressure
sprayer with spray wand (1500 psig to 3000 psig /
103 to 207 bar) to clean the entire element
surface. Hold the spray nozzle perpendicular
to the surface being cleaned to maximize spray
media penetration into the element. Alternately
spray each side of the element surface until clean.
3. The cleaning interval should be governed by the
amount and type of particulate in the system to
which it is installed and must be determined by
the user. To determine the maintenance interval,
the user should check the element in the rst few
months of operation to nd how quickly particulate
accumulates in the cells.
7
Enardo DFA Series
Outside North America Only

4. Thoroughly clean the gasket sealing faces being
careful not to damage the sealing surface. For
reassembly, use new gaskets and place them in
the machined recess of each interior ange on the
two conical sections.
5. Replace the ame element assembly with a new
assembly or properly cleaned and inspected
existing unit.
6. Locate the ame cell assembly such that it seats
onto the gaskets.
7. Replace all tensioning studs and tighten the outer
nuts hand tight only.
8. Torque the bolts in sequence as shown in the
Torquing Instruction section. Refer to Figure 5 and
Tables 4 and 5.
Note
Cleaning of units equipped with a cleaning
system may be accomplished in several
ways including periodic cleaning using
manually operated valves, by use of
an automated cycle timing method
or by having the cleaning operation
initiated whenever the pressure loss
across the arrestor element exceeds a
predetermined value.
Inspecting Enardo DFA Element
Assembly Following Flame
Propagation Event
1. Inspect the outboard ame cells for damage
immediately following a deagration, detonation
and/or stabilized burn.
2. Carefully remove the element assembly from
the arrestor.
3. Inspect the ame cells and the screens visually
for any signs of corrosion or other damage and
inspect the ame cells with a calibrated pin gauge
to ensure maximum crimp size openings do not
exceed the following values for their respective
gas group. Use the following pin gauges as
no-go gauges:
• Model Enardo DFA(E)***/D Explosion
Group D (IIA) – 0.063 in. / 1.6 mm
• Model Enardo DFA(E)***/C Explosion
Group C (IIB3) – 0.039 in. / 1 mm
4. If any damage is noted or crimp openings exceed
maximum size allowable as indicated by the entry
of the no-go gauge, replace the element assembly.
Note
Under no circumstance shall any element
assembly not provided by Emerson
be used in this assembly. Failure to
use the correct screens may lead to
arrestor failure.
Element Assembly, Disassembly
and Reassembly Instructions
WARNING
!
Isolate gas supply and bring system
to atmospheric pressure to prevent
ignitable gas from ashing while
performing maintenance.
CAUTION
Element assemblies are heavy and
require the use of adequate equipment
and manpower to prevent injury.
Note
Element assemblies are provided with
hinges and jacking nuts to facilitate
in-site cleaning of the ame cells or
removal of the element assembly without
the need for removal of the end sections
from the piping system. This method
is intended for use with detonation
arrestors installed in horizontal piping
congurations where adjacent piping is
fully supported such that no loads are
applied to the detonation arrestor.
CAUTION
Removal and installation of the detonation
arrestor and associated piping require the
use of adequate equipment and manpower
to prevent injury. Detonation arrestors
installed in inclined or vertical orientations
should be entirely removed from the
system for servicing.
8
Enardo DFA Series
Outside North America Only

Figure 5. Flange Pattern Tightening Sequence
1 2
5
4
7
6
3
1
23
4
1
2
3
4 5
6
7
81
2
3
4
5
67
8
9
10
11
12
1
2
3
4
5
7
89
10
11
12
13
14
15
16
6
1
3
2
4
5
6
7
8
9
10 11
12
13
14
15
16
17
18
19
20
28
28
1
1
5
5
9
13
17
21
25
9
13
17
21
25
29
3
3
7
7
11
11
15
15
19
19
23
23
27
31
6
6
2
2
10
10
14
14
18
18
22
22
26
26
30
32
4
4
8
8
12
12
16
16
20
20
24
24
159
13
17
21
25
29
33
37
41
3
7
11
15
19
23
27
31
35
39
43
2
6
10
14
18
22
26
30
34
38
42
4
8
12
16
20
24
28
32
36 40 44
8
27
Table 4. Tightening Steps and Torque Values for Internal Flanges(1)
MODEL PATTERN(2) BOLT SIZE TIGHTENING STEPS AND TORQUE (FT-LBS / N•m)
123456
Enardo DFA-300.5 15/8-11 Snug 20 / 27 40 / 54 60 / 81
Enardo DFA-0401 25/8-11 Snug 25 / 34 50 / 68 80 / 108
Enardo DFA-0602 23/4-10 Snug 40 / 54 85 / 115 125 / 169
Enardo DFA-0803 23/4-10 Snug 50 / 68 100 / 136 160 / 217
Enardo DFA-1004 37/8-9 Snug 50 / 68 90 / 122 145 / 197
Enardo DFA-1206 31-1/8-8 Snug 50 / 68 100 / 136 165 / 224
Enardo DFA-1608 41-1/4-8 Snug 50 / 68 120 / 163 190 / 258
Enardo DFA-2010 5 1-1/4-8 Snug 50 / 68 100 / 136 180 / 244 260 / 353
Enardo DFA-2412 5 1-1/2-8 Snug 75 / 102 150 / 203 280 / 380 400 / 542 500 / 678
Enardo DFA-2814 6 1-5/8-8 Snug 75 / 102 150 / 203 320 / 434 450 / 610 550 / 746
Enardo DFA-3016 61-3/4-8 Snug 80 / 108 200 / 271 350 / 475 500 / 678 700 / 949
Enardo DFA-3418 6 1-7/8-8 Snug 80 / 108 250 / 339 400 / 542 750 / 1017 1200 / 1627
Enardo DFA-3620 7 2-8 Snug 80 / 108 250 / 339 450 / 610 800 / 1085 1100 / 1491
Enardo DFA-4824 8 1-1/2-8 Snug 100 / 136 200 / 270 380 / 515 540 / 732 680 / 922
1. Using machine oil as lubricant. See Bolt Lubrication section on page 11 and torque correction factors for other lubricants in Table 5.
2. See Figure 5.
DESCRIPTION COEFFICIENT OF FRICTION MULTIPLY TORQUE VALUE IN TABLE 4 BY
Machine Oil f = 0.15 1.00
API SA2 Grease f = 0.12 0.80
Nickel-based Lubricant f = 0.11 0.73
Copper-based Lubricant f = 0.10 0.67
Heavy-Duty Lubricating Paste f = 0.06 0.40
Table 5. Torque Correction Factors for Common Lubricant
9
Enardo DFA Series
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NOMINAL PIPE
DIAMETER NUMBER OF BOLTS BOLT DIAMETER TORQUE
In. mm Ft-lbs N•m
1 4 0.50 12.70 912.20
1-1/4 40.50 12.70 13 17.63
1-1/2 40.50 12.70 18 24.40
2 4 0.63 16.00 35 47.45
2-1/2 40.63 16.00 41 55.59
3 4 0.63 16.00 60 81.35
3-1/2 80.63 16.00 34 46.10
4 8 0.63 16.00 43 58.30
6 8 0.75 19.05 80 108.5
8 8 0.75 19.05 109 147.8
10 12 0.88 22.4 101 136.9
12 12 0.88 22.4 135 183.0
14 12 1.00 25.0 168 227.8
16 16 1.00 25.0 159 215.6
18 16 1.13 28.7 244 330.8
20 20 1.13 28.7 214 290.2
24 24 1.25 31.8 253 343.0
Assumptions: Use of SAE grade 5 bolts or studs or stronger.
No lubricant.
Compressed mineral ber material or similar.
Notes: If lubricant is used on bolts, apply torque reduction factor listed in Lubricant Table.
For best results hardened steel washers should be used on all cast ange bolted connections.
Table 6. Torque Values for Raised Face Connection Flange (Steel Only)
NOMINAL PIPE DIAMETER NUMBER OF BOLTS BOLT DIAMETER TORQUE
In. mm Ft-lbs N•m
1 4 0.50 12.70 14 18.98
1-1/4 40.50 12.70 16 21.69
1-1/2 40.50 12.70 18 24.41
2 4 0.63 16.00 32 43.39
2-1/2 40.63 16.00 43 58.30
3 4 0.63 16.00 47 63.72
3-1/2 80.63 16.00 26 35.25
4 8 0.63 16.00 32 43.39
6 8 0.75 19.05 49 66.44
8 8 0.75 19.05 68 92.20
10 12 0.88 22.4 69 93.55
12 12 0.88 22.4 98 132.9
14 12 1.00 25.0 138 187.1
16 16 1.00 25.0 125 169.5
18 16 1.13 28.7 142 192.5
20 20 1.13 28.7 135 183.0
24 24 1.25 31.8 156 211.5
8 API 16 0.50 12.70 20 27.12
20 API 16 0.63 16.00 75 101.7
24 API 20 0.63 16.00 75 101.7
Assumptions: Use of SAE grade 5 bolts or studs or stronger.
No lubricant.
Elastomer <70 Durometer Shore A.
Notes: Flat faced anges should never be mated to a raised face ange for installation.
If lubricant is used on bolts, apply torque reduction factor listed in Lubricant Table.
For best results hardened steel washers should be used on all cast ange bolted connections.
Table 7. Torque Values for Flat Face Connection Flange (Steel or Aluminum)
DESCRIPTION COEFFICIENT OF FRICTION MULTIPLY TORQUE VALUE IN TABLE 6 BY
Machine Oil f = 0.15 0.75
API SA2 Grease f = 0.12 0.60
Nickel-based Lubricant f = 0.11 0.55
Copper-based Lubricant f = 0.10 0.50
Heavy-Duty Lubricating Paste f = 0.06 0.30
Table 8. Torque Correction Factors for Common Lubricants Applied on Flanges
10
Enardo DFA Series
Outside North America Only

1. Loosen all outermost nuts on tension studs.
2. Tighten the inside jacking nuts on the tension
studs forcing the two conical sections apart. When
the two ange faces have separated, remove the
tension studs that do not have inside jacking nuts,
so that the element assembly can be removed.
The inside jacking nuts are installed on all tension
studs that facilitate jacking the unit apart. The
inside jacking nuts are not installed on tension
studs that are taken out, for ease of removal.
3. Thoroughly clean the gasket sealing faces being
careful not to damage the sealing surface. For
reassembly, lightly grease one side of a new
gasket and place it in the machined recess of each
interior ange on the two conical sections.
4. Replace the ame element assembly with a new
assembly or properly cleaned and inspected
existing unit.
5. Loosen the jacking nuts on the tension rods until
the ame cell assembly seats onto the gaskets.
6. Replace all tensioning studs and tighten the outer
nuts hand tight only. Check to be sure that all the
jacking nuts are completely loose and not making
contact with the ange face.
7. Torque the bolts in sequence as shown in the
Torquing Instruction section.
Torquing Instructions
CAUTION
Excessive or uneven torque can
cause permanent damage to gaskets
and housing.
Tools/Supplies Required
• Hand operated conventional torque wrench or
power assisted torque wrench appropriate for the
specied torque.
• Socket wrenches of the proper size to t the hex
nuts being tightened.
• Molydisulde based lubricating paste. Molykote® G-n
or equivalent.
• Brush suitable for applying lubricant to the studs.
• Wiping rags necessary for the clean up of
excessive lubricant.
Molykote® G-n is a mark owned by Dow Corning Corporation.
Procedure
1. Use studs and nuts that are free of visible
contamination and corrosion.
2. Apply lubricant to the threads of the stud protruding
outboard of the interior anges and to the face of
the hex nuts which will contact the ange.
3. Assemble the nuts to the studs such that the
amount of thread extending outboard beyond the
nut is approximately equal on both ends.
4. Tighten the nuts to the torque values shown
in Table 4 following the designated sequence,
repeating the sequence as shown. Flange pattern
tightening sequences are shown in Figure 5.
Bolt Lubrication
Lubrication affects required torque of clean fasteners
in good condition more than any other factor. In fact,
90% of applied torque goes to overcome friction while
only 10% actually stretches the bolt. Table 4 assumes
that only machine oil is used as a lubricant. Table 5
shows a list of several common lubricants and their
effect on torque required to stretch bolts to 50% of
their yield strength. Most are available from local
bearing distributors.
Recommended Spare Parts
For installations that require frequent maintenance
and minimum downtime, it is recommended that the
user purchase a spare element assembly and several
spare element gaskets. The spare element assembly
can be installed immediately and the dirty assembly
can then be cleaned and stored as a spare for the next
maintenance interval.
Note
Element gaskets must be replaced each
time the cell assembly is loosened and
removed to ensure a gas tight seal.
Parts Ordering
When corresponding with your local Sales Ofce about
this equipment, always reference the equipment serial
number stamped on the nameplate.
11
Enardo DFA Series
Outside North America Only

Enardo DFA Series
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Technologies, Inc. All rights reserved. 01/19.
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