Installation
Manual
Rev. 3a, 11/30/2005
COR*Guard LLC – An innovative, cost-effective manufacturer of
fluoropolymer coated stainless steel duct, cleanroom furniture and other custom
products
INSTALLATION MANUAL TABLE OF CONTENTS
PRE-INSTALLATION
INFORMATION.. 3
Introduction. 3
System Design. 3
SMACNA. 3
Warranty. 3
Receiving. 3
Product Care. 3
Product Inspection. 4
Visual Inspection. 4
Electronic
Inspections. 4
FLANGE SYSTEMS. 5
Angle Rings. 5
Prime*Guard™
Unattached Rings. 5
Prime*Guard™
Attached Rings. 5
Prime*Guard™ Seal
Welded Rings. 6
DUCT ASSEMBLY.. 7
Gasket 7
Hardware. 7
Connecting
Sections. 8
Attaching to
Non-Prime*Guard Ductwork. 10
FIELD MODIFICATIONS. 10
Shortening Duct in
the Field. 10
1. Disassembly. 10
2. Measuring the
Modification. 10
3. Cutting the Duct 10
4. Filing the Edges. 10
5. Flange Tool 11
6. Adjusting the
Flange Height 11
7. Flanging the Duct
End. 11
8. Inspect the
Coating. 11
FIELD INSTALLED FLANGE. 12
FIELD INSTALLED NIPPLE. 13
NPT Nipple. 13
INSTALLING A TEST PORT. 13
3/8” Test Port 14
FIELD INSTALLED SADDLE TAP. 14
SPARK TEST PROCEDURE. 15
Spark Detector 15
COATING REPAIR.. 15
Precautions. 15
Preparing the
Repair Area. 16
Sizing the Patch. 16
Applying the Patch. 16
1. Heating the Area. 16
2. Place the Patch. 16
3. Flowing the Repair
Patch: 16
Spark Test
Inspection. 16
Technical
Assistance. 16
PRE-INSTALLATION INFORMATION
The purpose of this Manual is to provide information for the
proper handling and assembly of COR*Guard’s™ Prime*Guard™ ductwork. By following these tried and proven methods
the safety, the reliability, and the longevity of the system will be insured to
function as it was originally designed. All
Prime*Guard™
products are factory inspected and certified to meet all quality standards
before being shipping from the factory.
The installer is obligated though, to re-inspect and verify that all
products are serviceable before being installed and put into commission. It is the responsibility of the owner to
assure that the installer has followed inspection procedures, if the installation
is sub-contracted.
System
Design: Prime*Guard™
ductwork is manufactured to meet or exceed all SMACNA requirements for Round
Industrial Duct. Depending on the duct
sizes and the pressure classification of the exhaust system, reinforcing angle
rings may be required. Refer to SMACNA
“Industrial Duct Construction Standards” for these reinforcing requirements to
maintain SMACNA compliance.
SMACNA: All ductwork shall be supported
in accordance with the latest version of guidelines established by SMACNA. During the installation process special care
must be taken not to damage the coating.
The inspection process should insure the reliability of the coating, but
if the coating is damaged during the installation process the system will fail
to work as designed. Do not penetrate
the coating for any reason, except in the case of approved COR*Guard™
modification systems. Do NOT use
“Tek” screws, rivets, or other related fasteners that penetrate any coated
surface on ductwork, unless specifically allowed by SMACNA or specifically
stated in COR*Guard™ procedures.
Remember, do NOT install any ductwork that has failed a visual or
electronic inspection until it has been repaired and re-inspected. All fittings, balancing dampers, blast gates,
drains, test ports, and other inline accessories must be provided by COR*Guard™
to maintain the proper system design and warranty.
Warranty: COR*Guard™ will warranty
products for quality and workmanship for one (1) year from the date of
commissioning. Field installations,
modifications, repairs, and other post-installation operations shall be
performed using factory-authorized procedures.
Prior to any field repairs or other modifications, notify COR*Guard™ to
receive a Field Modification Authorization (FMA) from an authorized COR*Guard™
representative. Failure to follow these
procedures or to notify COR*Guard™ may result in voiding the warranty.
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Prime*Guard™ components are inspected and packaged at the
factory to assure that they arrive in perfectly new condition. Products though, can be damaged while in
transit to the delivery site. Any claim
for damage, loss, or delay as a result of the freight company, MUST BE
identified on the bill of lading and filed with the delivery company by the
consignee. If this is not done, the loss
will not be recognized as valid by the delivery company, and the cost will be
borne by the consignee. The consignee is
responsible for inspecting the shipment upon arrival for damages and
completeness and noting any issues on the bill of lading before taking receipt
of the shipment. It is then also the
consignee’s responsibility to notify COR*Guard™ within 48 hours of receipt of
any unsatisfactory product.
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Once the product has arrived at the job-site, proper
handling and storage of Prime*Guard™ duct is essential to its eventual
successful installation. Handle and
store Prime*Guard™ ductwork carefully to make sure the coating is not damaged
in any way. All COR*Guard™ items are
shipped from the factory with packaging designed to protect the coated duct
from damage due to handling and other debris, but proper care must still be
used to protect the coating.
When storage of the duct is required, it should be left in
the factory-installed packaging to maintain its cleanliness and to protect the
coating. Store the items in a location
that protects them from damage by traffic and other debris. If possible, store all the items indoors
where dirt and other debris cannot come into contact with the coating. However, if you must store the items outside,
then the ductwork should be protected with waterproof materials to protect it
from dirt, dust and other damaging elements.
If it is necessary to stack the items, place a barrier, such
as plywood, between the layers. The open
end of each duct section is the area most susceptible to damage of the
coating. Although, the ends are wrapped
in packaging care must be taken to avoid an object penetrating the packaging
and damaging the coated surface. If the
duct sections are stacked horizontally, do not overload the bottom layer and
compress the round diameter into an oval.
When moving Prime*Guard™ duct and fittings by hand, do not drag them
along the ground, which could scrape and damage the coating. Remove the factory-installed packaging ONLY
when the item is ready to be inspected and then installed. Although the items are made from a steel substrate,
it must be kept in mind that the coating is relatively delicate and damage to
it will compromise the entire system.
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A clean work area is imperative for handling and inspecting
the Prime*Guard™ ductwork so that it maintains its serviceability once
installed. All work areas and employee
hands should be cleaned before handling the coated duct. The objective is to clean any dust, dirt, or
other contaminates from the duct pieces before proceeding with the inspections
and to keep the items in this cleaned condition until they are installed. Proceed with the project ONLY when the
conditions are satisfactory for beginning this step. If unsatisfactory conditions exist, make the
effort to correct the situation before proceeding.
All COR*Guard™ products are inspected and certified to meet
quality standards prior to leaving the factory.
The consignee and installer though, are responsible for re-inspecting
and verifying, just prior to installation, that all ductwork has been kept in a
serviceable condition. Leave all the
factory packaging in place until the items are ready to be inspected and then
install immediately thereafter. Handle
with the utmost care to avoid damaging the coating.
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Table of Contents -
Visual Inspection
Begin the inspection by visually looking for dents in the
metal. Check the flanges on each end to
assure that they are still in the proper shape.
Continue the visual inspection by next checking the coating. Look for areas, especially on the flanges,
where the coating may have been scuffed or scraped. Visually check to see if any foreign items
have become imbedded in the coating. Tag
or identify any areas that are damaged or appear questionable.
Next, electronically inspect the coating using a spark
tester. Check that the setting on the
tester is correctly set for the given coating thickness. Sweep the entire coated surface with the
brushes of the wand to check for areas that no longer have the recommended
coating in place. Pay particular
attention to the “tagged” areas that may have been damaged, scraped or
scuffed. Tag or identify any points that
fail the spark test. Any point that
“sparks” constitutes a failure of that item for installation until the failure has
been corrected and retested.
Follow the spark test with an inspection of the coating
thickness. Make sure that the thickness
gauge is set for non-ferrous metal.
After properly “zeroing” the gauge, pick random points on the coated
surface to take readings. The average of
all the readings should be within the specified thickness. If one reading is significantly outside the
desired thickness, check several points close to that area to verify the actual
coating thickness in that region.
Identify any specific areas that are not acceptable. If the average thickness is outside the
specified thickness identify the item as unacceptable.
An item is acceptable for installation and service only when
it has passed both the visual inspection and the electronic inspections. COR*Guard recommends that the approved
section of duct be tagged in some visual manner to easily identify that it has
pass all the necessary inspections.
If an item has had the coating damaged enough to expose the
stainless steel, or if it fails a spark test, or it does not have the proper
coating thickness, the item is unacceptable for installation at that time. Tag or clearly mark any items that fail the
inspection tests so that these items do not inadvertently become
installed. Segregate these unacceptable
items in one area that is clearly identified as such. Contact COR*Guard’s Quality Control
department with the information regarding each item that has failed and why it
has failed the inspection. COR*Guard’s
personnel will discuss the appropriate measures that need to be taken for each
item. However, most “unacceptable” items
can be repaired in the field without necessitating a replacement part. Instructions for field repairs and a repair
kit from COR*Guard will be necessary though.
Any damaged duct that cannot be field repaired must be replaced or returned
to COR*Guard for factory repair. Take
tremendous care to protect the coating throughout the entire process of
inspection to insure excellent performance from the system.
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Prime*Guard™ ductwork is manufactured and should be
installed according to SMACNA procedures for round industrial duct. This is accomplished by bolting angle ring
joint systems together in a specific and systematic process. Please refer to the latest edition of SMACNA
to review the standards for this process.
The diameter of the angle rings can range in size from 4” to 120”. The specific design for the angle ring
connection system varies depending on the diameter of the duct, the gage of the
material, and the pressure requirements of the system.
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Figure #1: Unattached angle
rings
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Prime*Guard™
Unattached Rings: The
standard joint design is an unattached angle ring and a retaining flange on the
end of the duct. The diameter of the
duct, the gage of the metal, and the negative pressure rating will determine
the range in which this design is appropriate.
Refer to the SMACNA manual or contact a COR*Guard representative for
details. Angle rings can be manufactured
from material that is either black iron or 300 series stainless steel. As shown in Figure #1, a gasket and fasteners
complete the system.
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Figure #2: Attached angle
rings
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Prime*Guard™ Attached Rings: Duct pieces can
be manufactured with angle rings that are stitch welded directly to the duct
sidewall. The duct itself though, still has
flanges on each end. The angle rings are
manufactured from 300 series stainless steel.
The diameter of the duct, the gage of the metal, and the negative
pressure rating will determine the range in which this design should
function. Figure #2 illustrates this
system. The fastener hole locations in
the attached angle rings are designed to straddle the vertical centerline of
the duct when installed, unless otherwise specified.
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Figure #3:
Seal welded angle rings
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Prime*Guard™ Seal Welded Rings: Ducts that are
large in diameter are manufactured without duct flanges at all. The angle rings are seal welded directly to
the end(s) of the duct and form the end flange in this manner. The angle rings are made from 300 series
stainless steel. The diameter of the
duct, the gage of the metal, and the negative pressure rating will determine
the range in which this design can function.
The standard fastener hole locations straddle the vertical centerline
unless otherwise specified. Again, note
the location of the gasket in Figure #3.
Unless otherwise specified, Prime*Guard™
ductwork will include all necessary gasket material and hardware required to
assemble all the connection joints.
Gasket: The
gasket material shall be a Gore-Tex® form-in-place, fully expanded 100% PTFE
joint sealant. Use of other gasket material will void the warranty and could
adversely affect the performance of the system.
Depending on the diameter of the duct section, a specific size of joint
sealant is required. It is vital that
the appropriate size seal is used so that a watertight seal can be formed. Refer to Table #4 to size the joint seal to
the appropriate duct diameter. If a duct
joint has been disassembled for any reason after having the bolts tightened, a
new gasket must be installed during reassembly to ensure a secure watertight
seal.
Note that specific gasket sizes are
used for particular size ducts.
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Duct Diameter
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Gasket
Size
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4” to 10”
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3/16”
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12” to 48”
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1/4”
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50” to 120”
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3/8”
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Table #4: Duct & Gasket Sizing
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Hardware: Prime*Guard™ ductwork is shipped with all the
hardware required to assemble the connection joints. Each fastener hole will have an appropriate
size bolt, nut, lock washer, and two flat washers. All hardware shall be plated SAE Grade 5
fasteners. Stainless steel fasteners are
available upon request, although they are not recommended. Using unapproved hardware will void the
product warranty. Bolt sizes and torque
specifications vary based upon the size of the duct. Please refer to Table #6 for the specific
sizes and torque specifications.
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1. Verify
the Section: Identify
the correct duct section to be installed and locate the tag identifying that it
has been inspected and approved. If
there is any doubt regarding the inspection approval on the item, return it to
be inspected and tagged. If the item is
identified as having been inspected and approved, proceed by using a clean,
lint-free cloth to wipe the coated surface of the duct to remove any dust or
foreign particles. Make a last visual
inspection of the coated flanges to insure no damage has occurred since the
prior inspection. Do NOT install any
piece of duct that is visibly damaged.
Return any items for re-inspection that are in doubt.
2. Size
the Gasket: The
gasket material typically is provided in a roll of 50 to 75 feet. Therefore, the gasket must first be cut to
the proper length. Being careful to keep
the adhesive covering in place, unroll enough gasket material until it can be
wrapped around the diameter of the duct section with an overlap of
approximately 2 inches. Cut the
described length of gasket from the remainder of the roll. Only one (1) gasket is required for each
connection joint.
3. Apply
Gasket: Peal
back the adhesive covering from the first 6 inches of one end of the gasket
that has been cut to length. Identify a
fastener hole that will be located on the upper half of the duct once it has
been installed. Apply 1” of the exposed
adhesive to the angle ring near that hole.
(refer to Figure #5) Smoothly
apply the entire gasket around the edge of the coated flange while stripping
the covering from the adhesive. Do not
allow the gasket to become wrinkled or allow the adhesive to become stuck to
the gasket. If the gasket becomes stuck
to the adhesive, or damaged, discard that section and cut a new length. Finish applying the gasket by making sure
some overlap (approximately 1”) occurs at the angle ring hole from which the
gasket started. (See Figure #5) Seat the
gasket on to the coated flange by running a finger around the gasket to firmly
set the adhesive onto the duct flange.
Note: On duct
that is manufactured without a flange and the angle ring is seal welded
directly to the duct, install the gasket directly onto the angle ring. As with other designs, identify an angle ring
hole that will be located on the upper half of the duct and begin to apply the
gasket. Apply the gasket material around
the diameter of the duct between the angle ring holes and the inside surface of
the duct. Continue to smoothly apply the
gasket to the entire face of the angle ring.
Finish by overlapping the gasket (approximately 1”) at the beginning
hole. Run a finger around the gasket to firmly set the adhesive onto the duct.
(Figure #5)
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Figure #5: Gasket Placement
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4. Bolt
Flanges: Align
the two duct ends to be joined. Take
care not to shift the duct from side-to-side and disturb or wrinkle the
gasket. Insert a few “starter” bolts on
opposite sides of the angle ring to position and hold the duct ends in
place. Each bolt should be installed
with a flat washer against the angle ring.
A lock washer should also be placed between the flat washer and
nut. Once the duct ends are correctly
positioned, hold them in place, insert the remaining bolts, and tighten the
nuts “finger-tight”.
5. Tighten
the Bolts: Follow a
star pattern when tightening the bolts.
Apply a gradual torque to all fasteners with a low-torque air wrench, or
by hand, until the appropriate compression is achieved. Tightening one bolt dramatically more than
the others can result in damage to the gasket and failure of the system. Once all the bolts have been tightened to
approximately the proper torque with the air wrench or by hand, use a
calibrated torque wrench to finish the tightening. Be sure to properly set the torque wrench to
the COR*Guard™ recommended torque value for each bolt size, before final
tightening. (Table #6)
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Standard hardware: SAE Grade 5 fasteners
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Torque Specifications
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Duct Diameter
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Bolt Size
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Ft. lb.
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In. lb.
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M kg.
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4” to 10”
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5/16”
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Grade 5
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22
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264
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3.0
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S/S
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8
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96
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1.1
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12” to 48”
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3/8”
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Grade 5
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36
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432
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5.0
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S/S
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15
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180
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2.1
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50” to 120”
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7/16”
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Grade 5
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60
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720
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8.3
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Table #6: Hardware size & torque specifications
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It may be desirable in some instances to attach Prime*Guard™
duct to an existing duct system. The
existing duct may be a Fiberglass Reinforced Plastic (FRP) or a coated metal
duct system and still allow a secure connection. COR*Guard will need specific details about
the existing flange that is to be connected to.
A custom built flange to mate with the existing system is easily
manufactured with the correct details.
Joining to FRP without a flange can also accomplished once specific
details are communicated and understood regarding diameters and desired
design. These circumstances are best
handled by contacting a COR*Guard representative directly to discuss the
particulars of each situation. This will
assure that the highest degree of compatibility is achieved.
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One of the major advantages of Prime*Guard™ duct is that it
can be modified in the field. This can
reduce “change-out” time and reduce cost by not having to purchase additional
custom items. Duct that is constructed
of 16 gage material or lighter can be field cut and flanged without damaging
the coating if done properly with the correct tools. However, this process has several steps which
can easily damage the coating if not done properly according to prescribed
methods.
1. Disassembly: Remove the section of duct that is to
be modified from its installed position.
Remove the seal material and properly discard them. Always use new seals when re-installing any
duct section.
2. Measuring
the Modification: Measure the distance between the
existing sections of duct where the modified duct has been removed. Slide the angle ring away from the flange end of the duct that is to be
cut, towards the portion of the duct that is to be saved and reinstalled. Add 3/8” to the length of the
measured distance. (This 3/8” is to
allow for the distance that will be lost when the flange is turned out.) Scribe a line completely around the
circumference of the duct that is to be cut at the desired length.
3. Cutting
the Duct: Use a center punch to mark a
location on the scrap side of the duct that will result in a drilled hole,
tangent to the scribed line. This will
be the starter hole where you will begin cutting. Drill the hole using a 1/8” drill bit. Then use a step drill to enlarge the pilot
hole up to a 3/8” or a 1/2" hole.
Enlarge the hole slowly to minimizing the heat produced. If too much heat is generated the coating may
be damaged. Using the hole as a starting
point, insert a double-cut power shear and cut along the scrap-side of the
scribed line. Inaccurate cutting may
result in ruining the item.
4. Filing
the Edges: Use a hand file to remove all
the burrs from the cut edge. Take care to avoid damaging the coating while
filing the edge. Remove all filings and
debris produced from either the cutting process or the hand file. Be careful not to imbed or scratch the coating
when removing the metal filings.
5. Flange
Tool:
Use only COR*Guard™ supplied rolls to insure the
duct is properly formed while maintaining the coating’s integrity. Before using the tool, make sure the rolls
are clean and free of damage. Any debris
or foreign material on either the rolls or the duct will be imbedded into the
coating if not cleaned prior to this step.
If the rolls have been damaged in some manner, this also can cause the
coating to be scored, cut or otherwise compromised.
6. Adjusting
the Flange Height: Adjust the flange tool stop as
required so that a 3/8” flange will be produced on the cut end of the duct when
finished.
7. Flanging
the Duct End: Check before proceeding that both angle
rings are properly positioned on the duct.
Use standard procedures for turning the flange on the duct. Remember that over-tightening the rolls can
pinch the coating and cause damage.
8. Inspect
the Coating: After the flange is completely
turned out, inspect the duct to ensure the Prime*Guard™ coating
was not damaged during the flanging process.
Check visually to see if any foreign items were imbedded into the
coating by the rolls. Perform a spark
test on the duct, thoroughly inspecting the flanged end. (See “Spark Testing” section of this manual
for instructions.) Inspect the other end
of the duct to insure that it was not damaged during this process. If the duct passes inspection, it is now
ready to re-install.
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In order to make a field installation of the flange, a
section of the duct must be removed from the system. The flange must be inserted through a hole
from the inside of the duct. Therefore
the section of duct to be removed may be the item in which the flange is to be
installed or the section directly adjoining if the location can then be
accessed.
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Figure #7: Field Installed
Flange
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1. Punch: Locate the
center of the desired location for the flange.
Mark the location using a center punch.
Drill a 3/8” pilot hole. Using a
hydraulic punch kit, punch the appropriate diameter hole.
2. Swage: Next swage the hole so that the
gasket will be allowed to form a proper seal to the duct.
3. Install: Wrap the Gore-Tex®
Joint Seal around the flange to determine the length of material needed. Add enough length so that the material can
overlap itself once installed and cut it from the roll. Remove the adhesive covering and apply the
gasket material to the inside flange of the fitting. Place the fitting into the swaged hole from
the inside of the duct so the gasket creates a seal between the flange and the
duct. Thread the lock ring onto the fitting until it is hand-tight. Use the correct size wrench on the jam nut
and the flats on the test port to tighten the lock ring until the gasket has
been compressed and seals against the inside of the duct. The lock ring should be tightened until
resistance is encountered to achieve this seal. The fitting is now installed. (Fig #7)
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To install this fitting the duct section, or the one
adjoining it, must be removed from the system.
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DESCRIPTION
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PUNCH SIZE
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MIN. HOST
DUCT SIZE
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1” NPT Nipple
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1-5/16” dia.
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6” dia.
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1-1/2” NPT Nipple
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1-7/8” dia.
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8” dia.
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2” NPT Nipple
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60 mm
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10” dia.
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Item includes: (1) Nipple,
(1) Jam Nut
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MAXIMUM
MATERIAL THICKNESS
Table
#8 16 gauge maximum for all Nipple sizes.
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The procedure for creating the hole to install the nipple is
the same as the flange.
1. Punch: Locate the center of the desired location for
the nipple. Mark this location with a
center punch. Drill a pilot hole to
accommodate insertion of the punch.
Punch the desired size hole.
2. Swage: Next swage the hole making sure
to use the proper size tool.
3. Installing
the Nipple: Measure and cut the proper length
of Gore-Tex® Joint Seal to allow for overlap once
installed. Apply the gasket to the
inside flange of the test port. Insert
the test port into the hole from inside the duct. Thread the jam nut onto the
nipple and tighten until hand-tight.
Tighten jam nut with a wrench while holding nipple on the flats with
another wrench. Make sure the gasket is
uniform and forms a seal to the duct wall.
The installation is now complete. (Fig #9)
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Figure #9:
Field Installed Nipple Setup
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Table of Contents -
INSTALLING A TEST
PORT
To install the test port, the duct can remain in the system
if already installed. The minimum duct
size the test port can be installed in is a 6” duct diameter if a 3/4"
test port is to be installed. A 3/8”
test port can be installed in as small as a 4” diameter pipe.
3/8” Test Port
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Figure #10: 3/8” Test Port
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1. Create
the Hole: Locate, center punch, and drill a
1/8” pilot hole in the desired location.
Next enlarge the hole to the appropriate diameter through use of a step
drill bit. Drill slowly to minimize the
amount of heat that is produced. Debur
the edge of the hole and remove any metal or coating fragments.
2. Install
the Fitting: Place the seal on the stem of the nipple with
the small side of the seal towards the threads of the nipple. Holding the nipple by the stem, put the
threaded end into the hole until all the threads are inside the duct. Carefully push the seal through the hole. Once the seal is inside the duct, pull the
stem back out of the hole until the threads are exposed. Secure the test port with the nut and torque
it to 15 inch pounds. (Fig #10)
3. Cutting
the Stem: Measure
approximately 1/4" from the end of the threads towards the duct and cut
through the stem. This will open the hole in the test port. The test port is
now ready to accept fittings with female threads.
4. Drilling
and Tapping the Test Port: The original inside diameter for
the 3/8” test port is 1/4", but it can be drilled out up to a maximum 3/8”
ID, or drilled and tapped to a maximum 7/16” diameter to accept a male fitting
if desired. The original inside diameter
for the 3/4” test port is 1/2", but it can be drilled out up to a maximum
3/4” ID, or drilled and tapped to a maximum 9/16” diameter to accept a male
fitting.
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Figure #11:
Field Installed Saddle Tap
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1. Cutting the Opening: Use the template provided with
the saddle tap to trace the outline on the duct where the new opening is to be
located. Use a center punch and the
template to mark where holes need to be drilled. In addition to bolt holes, holes need to be
drilled at each corner of the opening to accommodate cutting with the power
shears. Cut along the traced outline to
create the opening for the tap.
Carefully file the cut edges to remove any burrs and rough edges. Remove any filings or debris from the duct
section before proceeding. Be careful not
to damage the coating by rubbing the filings into the coating when cleaning is
performed.
2. Applying the Gasket: The gasket material needs to be “sandwiched” between the duct sidewall
and the interior saddle piece. Measure
the distance around the opening where the gasket will be located. Add an additional 2” to the measured
distance. Cut this length of gasket from
the roll of Gore-Tex® Joint Seal. Contact a COR*Guard
representative for the correct diameter of gasket material that is appropriate
for the tap being installed. Apply the
gasket to the interior saddle piece beginning near one of the middle
bolts. Continue around the entire
outside and finish by overlapping approximately 1” of the ends of the gasket
around this bolt. Refer to Figure #5.
3. Installing the Saddle: Carefully position the interior saddle inside
of the new opening taking care not to scratch or damage the coating. Once the interior saddle is in place, slip
the exterior frame over the stud bolts.
The interior saddle must be kept in place during this process or the
gasket may be moved out of place causing the tap to leak and fail. Install in order, a flat washer, lock washer,
and a nut onto the studs and tighten “finger-tight”.
4. Torque the Nuts: Use a low-torque air tool or a hand tool to tighten the fasteners. Tighten the bolts in at least three
successive sequences until close to the final torque. Alternate the fastener that is being
tightened in an opposing pattern.
Tighten the fasteners near the center first. Tighten the corner fasteners last to avoid
deforming the tap and not forming the proper seal. Do not tighten one stud all the way before
moving to the next fastener. Use a
calibrated torque wrench, set to the proper torque, to tighten the nuts. See Table #6 for specifications regarding
torque values.
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COR*Guard™ recommends the D.E. Stearns 14/20 Voltage
Regulated Holiday Detector. It is a portable, all-purpose electrical
inspection instrument for identifying non-complying coated surfaces. The detector needs to be set for the proper
voltage based upon each coating thickness being tested. Refer to the operating instructions provided
with the detector for setting the voltage.
1. Preparing
to Test: Make
sure the Prime*Guard™ product is clean both
externally and internally. Remove any
dust or debris from the surface using a soft, lint-free cloth. The cloth may be dampened with water or
Isopropyl Alcohol before wiping the surface.
2. Setting
the Detector: Determine
what the specified thickness of the coating was to be. Set the detector to the proper
voltage based on the manufacturer’s instructions. Make sure the ground strap is in contact
with only the base metal of the duct to be tested. Verify the functionality of
the detector by rubbing the electrode brush against the exposed metal duct. If
sparks are visible, and you hear an audible tone, the detector is properly
functioning. A weak battery will provide
inaccurate readings.
Caution: Make
sure you do not create a ground path with your body. Though the amperage of the
detector is not dangerous, it will generate an uncomfortable shock.
3. Testing
the Coating: Rub the
brush slowly over the entire coated surface, paying attention to flanges,
welds, seams, and geometric changes in the duct. Watch closely for sparks, and listen for the
audible tone that indicates a deficient area.
4. Recording
the Results: Record
the results of the inspection and/or tag the item. If there is no detection of deficiencies in the
coating, the piece has “passed,” and can be “tagged” as ready for
installation. If a deficiency in the
coating is detected, the piece has “failed”.
Mark the location of the deficient area so that it can easily be
identified again and segregate the item for either repair or replacement.
5. Processing
the “Failed” Part: The “failed” piece should be
visually inspected to determine if a field repair is applicable. If the deficient area is larger than 3/4” in
diameter the duct should not be field repaired.
The duct should be “rejected” altogether. It should immediately be “tagged” to identify
it as such, and segregated so that it is not installed in the system. Contact a COR*Guard representative
immediately to order a replacement part.
If the deficient area is smaller than 3/4'” in diameter the piece can be
field repaired.
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Pinholes, scratches and scuffs up to 3/4” in diameter in the
Dyneon fluoropolymer coating can be repaired in the field by following proper
methods. You
may also contact COR*Guard™ for more information about field repairs.
Perform the repairs in a ventilated and well lit area. If you are required to work in a confined
area, follow appropriate precautions for working in confined spaces. Respirators designed to filter vapors (e.g.
charcoal filters) are strongly recommended and safety glasses are required.
Clean the damaged or deficient area with a clean lint-free
cloth that has been dampened with alcohol.
If the damaged area has been roughed and/or has foreign debris embedded
in the coating, sand may be needed. If
sanding is required, use #220 grit Aluminum Oxide Sandpaper. Do not expand the damaged area with the
sandpaper. Use the sandpaper to smooth
the roughened coating and remove any imbedded material. Make sure the repair area is free of all
foreign particles before proceeding. After
sanding, wipe the coated surface of the duct to remove all sanded material and
other debris.
Cut a “patch” from the sheet of Prime*Guard™ repair material
using scissors. The patch needs to cover
the damaged area of the duct, plus overlap 3/8” onto the surrounding “good”
coating. This overlap needs to occur
around the entire perimeter of the damaged area.
1. Heating
the Area: Use an electric heat gun capable
of attaining 550 degrees Fahrenheit to slowly preheat the area. The duct should be heated from the bare metal
side of the duct directly opposite the repair area. The coating needs to be heated to
approximately 550 degrees Fahrenheit, but overheating can damage and ruin the
coating. Be extremely careful not to “burn”
the coating since dangerous fumes can be produced, besides ruining the
coating. Respirators should be worn to
protect against this occurrence. If the
coating begins to discolor or bubble it has been overheated, and the process
should be stopped. Once the coating
begins to attain the proper temperature its appearance will change slightly by
loosing some of its glossiness. Do not
allow the repair area to cool during this process.
2. Place
the Patch: While continuing to apply heat
so that the coating remains glazed and soft, place the patch material over the
area to be repaired. The patch material
must overlap onto “good” coating around the entire repair area. Since the coating is “tacky”, the patch must
be placed in the proper location at first contact. Use of needle-nose pliers or tweezers may
assist in positioning the patch material.
Begin to apply heat to the patch material directly and gently press the
patch into the heated, soft coating using a rounded, blunt object.
3. Flowing
the Repair Patch: Use the electric heat gun to
continue heating the patch material from both sides of the duct as needed,
until a consistent flow is achieved between the coating and the patch material.
Once the repaired area has cooled, inspect the area
visually. Look for coating material that
appears to not have been melted or coating that is discolored or bubbled. If it appears visually to be acceptable,
perform a “spark” test. (Refer to the Spark Testing Procedure in this guide
for specifics.) If the patch passes both
the visual test and the spark test, the duct should be approved for
installation.
If you need technical assistance with this process, contact
a COR*Guard™ representative at (208) 429-8896.
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