Miscellaneous
1.0 Scope This is the general
specification covering materials and procedures for the thin-film, CeRam-Kote
Ceramic Epoxy coatings. More detailed, job-specific specifications may be
obtained from CeRam-Kote, Inc.
2.0 General The
effectiveness of a coating as a corrosion preventative is dependent on whether
or not it forms a tightly adherent, impervious, chemically resistant barrier
over the surface of the substrate to be protected. All three of these factors
are directly affected by the quality of work performed by the coating
applicator. As a consequence, the coating applicator shall strictly follow all
the requirements set forth in this specification, the coating manufacturer’s
recommendations and good industrial practice. Workmanship shall be first class
in every respect.
3.0 Surface Preparation All
surfaces must be free of dirt, grease and oils prior to sand blasting or
abrading. If the part is used, alkali degreasers such as Devprep88, Klenzade
Alkali degreaser or BP Comprox HD alkali degreasers, or TSP (tri-sodium
phosphate) should be used before abrasive blasting. They should not be permitted
to dry on the substrate and should be rinsed from the substrate thoroughly with
clean fresh water.
3.1 Steel, Stainless Steel, Titanium, Aluminum
Grit blast, with sand, steel, garnet, plastic or other media, etc., all metal
material ideally to a NACE-1 (SSPC-SP5, Swedish-Sa 3) White Metal but no less
than NACE-2 (SSPC-SP10, Swedish-Sa 2 ½) Near White Metal finish. At all times,
an anchor profile should be 2 to 2 ½ mils (50 - 62.5 microns).
For stainless steel and aluminum, if necessary, blasting
for profile may be done in the days prior to the application, but the surface
must be additionally sweep or brush off blasted the day of the application to
ensure all oxides have been removed and chlorides are at a minimum.
3.2 Fiberglass and composite materials When
preparing old or previously used fiberglass or plastic material, it is important
to clean the substrate to ensure all contaminants are removed before abrading.
CeRam-Kote recommends hot water pressure washing (at least 3,000 psi) using trisodium phosphate or detergent. Allow to dry. Rough up or abrade with 40-grit
to 80-grit sandpaper. For new fiberglass, clean and wipe all surfaces with
Acetone or Methyl Ethyl Ketone (MEK) prior to profiling to remove mold release
agents, wax and contamination prior to abrading. Fiberglass and composite
materials must have a water content of less than 5%.
3.3 Galvanized If the surface is newly galvanized
(that is, less than 48 hours out of the zinc kettle), the surface can be coated
after a slight roughening of the surface (i.e., 100 grit sandpaper or abrasive
sweep blast*). If the surface of the galvanized part has been exposed to the
environment for more than 1 year, the surface can be coated after the dirt,
grease, oils, and salt contamination have been removed (i.e., either solvent
wipe, alkaline wipe, etc). The most difficult time to paint galvanized steel is
between 1 day and 1 year after it has been galvanized. CeRam-Kote recommends sweep
blasting* of the galvanized surface to remove the natural corrosion by-products
of the galvanized surface {i.e., ZnO and Zn(OH2)}.
*Care should be taken to prevent removing too much of
the galvanized coating. Particle size for a sweep blast of galvanized steel
should be between 200 and 500 m.
3.4 Welds, joints, and edges All welds are to be
ground reasonably smooth, removing all weld splatter and slag. Sharp edges in
areas to be coated shall be ground to a minimum radius of 1/16” of an inch (1.5
mm).
3.5 Ultra-High Pressure Water Jetting All
surfaces to be recoated shall be cleaned in accordance with NACE/SSPC WJ-1/SC-1
with UHP WJ of at least 30,000 psi (2,000 bar). Do not use corrosion inhibitors.
Chloride removers should be used as a substitute. If in an enclosed area,
dehumidification equipment should be used to ensure quick drying of the
substrate. CeRam-Kote thin-film coatings should be applied as soon as possible
to limit the amount of flash rusting that occurs. C Vis WJ-2 L and C Vis WJ-2 M
are acceptable. C Vis WJ-2-H is not acceptable per SSPC-VIS 4(I) / NACE 7 visual
standards. Once the rust is adhered and classified as corrosion of the
substrate, then the rust is no longer acceptable.
**Prior to coating, all surfaces should be tested for
chlorides. Ten (10) ppm of chlorides is the maximum level for internal or
immersion service (internal vessels) and twenty (20) ppm is the maximum for
external or atmospheric service (pipelines, external vessels). The acceptable
level for hulls below the water line is <3 ppm. Any readings outside of the
above-specified parameters will be treated with a soluble salt remover.
All surfaces must be free of contaminates. CeRam-Kote
recommends checking all substrates for salt contamination prior to blasting and
prior to coating.
4.0 Mixing CeRam-Kote
thin-film Ceramic Epoxy Coatings are packaged in two cans, Part A (coating) and
Part B (curing agent). The mix ratio varies for each CeRam-Kote formula. Please
refer to individual Product Data Sheet for volume and weight mixing ratios.
Shake Part A (coating) with a Cyclone air powered shaker or mix Part A with a
air / electric paddle mixer until all the ceramic powders are suspended in the
resin. The time required to place the ceramics into suspension depends on how
long the material has been on the shelf and the temperature of the storage
facility. Regardless of time needed, shake or mix all ceramic material into
suspension first.
4.1 When using a Cyclone Air Shaker If Part A
(coating) sits for 30 days or less at room temperature 72*F (22.2*C) and the air
powered shaker is in good working order, a four (4) to six (6) minute shake will
place the ceramic powders into suspension. If Part A (coating) sits in excess of
30 days or at a colder temperature than room temperature 72*F (22.2*C), a longer
shake will be required to place the ceramic powders into suspension. If all the
ceramic powders of Part A (coating) are not in suspension, the ceramic and resin
ratio becomes unbalanced and the material will not cure or perform properly.
Check the coating to assure that all solids are in suspension prior to
proceeding to the mixing step. Stirring, other than the use of the air powered
Jiffler system described below, will not get the ceramic powders into
suspension.
Combine Part A (coating) and Part B (curing agent) and
stir until both parts are thoroughly mixed. Continue stirring the mixed material
until no streaking is observed. Never allow the catalyzed coating to get above
100*F. The pot life for CeRam-Kote Ceramic Epoxy Coatings at 72*F (22.2*C) is
approximately one (1) hour. Colder temperatures will increase the pot life and
warmer temperatures will decrease the pot life.
4.2 When using a paddle mixer: CeRam-Kote Ceramic
Epoxy Coatings can be mixed by using a paddle mixer. This mixer can be used for
one (1) gallon kits at on-site jobs where the use of the Cyclone Air Shaker is
not practical or where five (5) gallon kits are to be used. This mixer places
CeRam-Kote Ceramic Epoxy Coatings Part A into suspension prior to adding Part B
and is also used to make the catalyzed mix.
When Part A (coating) is stored for 30 days or less at
room temperature 72ºF (22.2ºC)) and the air motor is in good working condition,
a fifteen (15) to twenty (20) minute mix will place the ceramic powders into
suspension in a five (5) gallon pail. A ten (10) to fifteen (15) minute mix will
normally place the ceramic powders in a one (1) gallon can in suspension. When
mixing, stop after five (5) or six (6) minutes and scrape the sides of the
container. Regardless of time needed, mix all ceramic material into suspension
prior to proceeding.
When Part A (coating) is in suspension, add Part B
(curing agent). The amount of time required to make a mix depends on the
temperature of parts A and B and the working condition of the mixer. For a five
(5) gallon pail, Part A (coating) and Part B (curing agent) should be mixed for
three (3) or four (4) minutes at room temperature 72*F (22.2*C). For a one (1)
gallon can, two (2) or three (3) minutes should be sufficient. Caution must be
used to prevent heat build up. The pot life of CeRam-Kote Ceramic Epoxy Coatings
at 72*F (22.2*C) is approximately one (1) hour. Colder temperatures will
increase the pot life and warmer temperatures will decrease the pot life.
4.3 Thinning CeRam-Kote thin-film coatings are
shipped from the factory with a viscosity of 60-90 seconds so thinning will be
required prior to application. Adjust viscosity with small amounts of CeRam-Kote
Thinner #1 or #3. Use caution when thinning, as a little thinner goes a long
way.
*dependent on ambient temperature
5.0 Coating Application For
best results, spray-apply CeRam-Kote thin-film, Ceramic Epoxy coatings. Use
pressure feed equipment such as high-volume, low-pressure (HVLP) equipment,
conventional, or airless spray equipment. The compressed air source should be
outfitted with air dryers as needed to supply moisture-free air. If in an
enclosed area, dehumidification equipment should be used to ensure continuous
drying of the substrate. Moisture inhibits the catalytic reaction and produces
an unsatisfactory finish that performs poorly.
Airless equipment may be used to apply CeRam-Kote
Ceramic Epoxy Coatings to large areas. The carbide tip should be reversible and
have an orifice size of 0.019-0.027 inches.
CeRam-Kote Ceramic Epoxy Coatings may also be brush or
roll applied. To brush, use a very fine bristled brush with natural bristles. To
roll, use a high quality roller with a ¼ inch (6.35 mm) or shorter nap.
Stripe Coating: All welds, joints, edges, and angle bars
must be stripe coated with a light pass of two (2) to three (3) mils either by
brush or spray application. Structures that cannot be reached by spraying must
be stripe coated as well. It is recommended that contrasting colors of
CeRam-Kote be utilized during this process to ensure proper coverage.
Apply a first pass of four and one-half (4½) to six (6)
mils to the entire substrate (including the areas previously striped) and allow
it to sit until tacky. Normally, thirty (30) to forty (40) minutes is
sufficient, but allow more time if the temperature is below 70*F (21.1*C) or if
more time is simply needed. Apply a second pass of four and one-half (4½) to six
(6) mils to the entire substrate for a total dry film thickness (DFT) of seven
(7) to ten (10) mils. Apply additional mils, if recommended by factory, without
incurring runs or sags.
Whenever possible, always apply the second coat in a
cross-coat method to the first coat.
The finished application of the material appears glossy
when wet. At room temperature 72*F (22.2*C) CeRam-Kote Ceramic Epoxy Coatings
gel in approximately three (3) hours, a seventy percent (70%) cure is achieved
within twelve (12) hours. A full cure is achieved in 2 to 7 days, depending on
curing temperature.
Should a more rapid cure be desired, CeRam-Kote
thin-film, Ceramic Epoxy Coatings can cure in one (1) hour if the temperature is
elevated to 150*F (65.6*C); however, some flexibility is lost by rapid-curing.
Unless in a controlled environment, coating will only be
permitted during daylight hours when air and substrate temperature is above 40*F
(4.4*C). No coating will be permitted when substrate is wet from rain or dew,
when surfaces are less than 5*F (3*C) above the dew point, or when the relative
humidity is greater than 85%. Moisture will inhibit the curing agent reaction in
the coating system and the coating will not cure or perform properly.
To achieve highest gloss possible, and to deter amine
blush issues with CeRam-Kote 54® and CeRam-Kote 99:
Once substrate has been coated, wait at least 5 minutes,
but not longer than 30 minutes. Apply 120°F to 130°F (49°C to 54°C) heat to
coated item. Allow substrate of item to reach 120°F to 130°F (49°C to 54°C).
Once this occurs, remove heat.
6.0 Top Coating CeRam-Kote
Ceramic Epoxy Coatings with an Epoxy Compatible Topcoat
6.1 For optimum adhesion, CeRam-Kote Ceramic
Epoxy Coatings must be topcoated when the CeRam-Kote Ceramic Epoxy Coating is
still soft but dry to the touch (using thumbnail impression test, the coating
will be marked but will not adhere to thumbnail). This is the preferred
topcoating application method.
6.2 Alternatively, if the CeRam-Kote Ceramic
Epoxy Coating is cured beyond the dry to the touch stage:
6.2.1 Solvent wipe surface to remove contaminates
6.2.2 Lightly sand with 80-100 grit paper. 6.2.3 Solvent wipe to remove any
residue. 6.2.4 Apply a mist coat of the CeRam-Kote Ceramic Epoxy Coating. 6.2.5
Apply the epoxy compatible topcoat per instruction in 6.1 above.
6.3 For option 6.1, if the coating is beyond the
dry to the touch stage, the surface must be checked for chloride contamination.
Ten (10) ppm of chlorides is the maximum level for internal or immersion service
(internal vessels) and twenty (20) ppm is the maximum for external or
atmospheric service (pipelines, external vessels). The acceptable level for
hulls below the water line is <3 ppm. Any readings outside of the
above-specified parameters will be treated with a soluble salt remover.
7.0 Safety Wear a
charcoal-filtered mask, safety glasses, and gloves when applying CeRam-Kote
Ceramic Epoxy coatings. Read the Material Safety Data Sheet (MSDS) completely to
ensure that all safety procedures are followed.
8.0 Clean Up Purge and clean
spray equipment within thirty (30) minutes of the final spray. Flush equipment
with Acetone or Methyl Ethyl Ketone (MEK) until solvent sprays clear.
Disassemble and clean equipment to manufacturer’s recommendations. Material left
in spray equipment could solidify and damage equipment. Use precautionary
measures applicable to any catalyzed material.
9.0 Repairs If the
CeRam-Kote coating is less than forty-eight (48) hours old and has not been
exposed to contamination, repair by wiping with Acetone or Methyl Ethyl Ketone (MEK)
then reapply CeRam-Kote Ceramic Epoxy coating.
If coated parts have been exposed to contamination
and/or coated for longer than forty-eight (48) hours, repair by sanding with 40
to 60 grit sand paper then wipe with Acetone or Methyl Ethyl Ketone (MEK). Make
certain the substrate is totally free of all contamination and is white-metal
clean NACE-1, no less than NACE-2. Once the substrate is totally clean of
contamination, reapply CeRam-Kote Ceramic Epoxy coating to specification. If
amine blush or water spotting has occurred, be aware this is only cosmetic. It
has only occurred at the air-to-coating interface. The surface must be sanded
aggressively to remove the contamination back to unaffected coating before
another coat of CeRam-Kote Ceramic Epoxy coating can be applied.
If the coated parts have been exposed to actual
operating conditions for longer than seventy-two (72) hours, the effected
substrate must be cleaned to NACE-1 white metal, no less than NACE-2 Near white
metal. Ideally, sandblasting the effected substrate is best to achieve the
needed anchor profile and to remove all contamination. Second option is to sand
with 40-grit sandpaper to achieve contamination free substrate. It is
recommended the substrate be checked for soluble salts before and after
substrate preparation (see section 6.3 above for limits).
10.0 Holiday Detection Use
a 67½-volt, wet sponge spark detector set at 80,000 ohms resistance, such as
Tinker and Rasor model M-1. If a holiday is detected, mark the area with an oil
free chalk and repair according to 9.0.
11.0 Coverage The formula
for theoretical coverage of CeRam-Kote thin-film, Ceramic Epoxy Coatings without
considering loss factors is:
1604 X Solids Content by Volume Dry Film Thickness
Required in Mils = ft2/gal Theoretical Coverage
12.0 Pot Life and Shelf Life
Pot life is approximately one (1) hour at 72*F (22.2*C) with medium humidity.
Colder temperatures will increase the pot life and warmer temperatures will
decrease the pot life. Excessive heat decreases pot life rapidly. At 100*F
(37.8*C) the pot life is 20-minutes.
CeRam-Kote Ceramic Epoxy Coatings have an indefinite
shelf life. Preferred storage/usage is a dry enclosed area under 85°F (29°C),
used within two (2) years. However, if stored more than two years above 85°F
(29°C), call CeRam-Kote Technical Support prior to use.
13.0 Cure Schedule A two-pass
film of seven (7) to ten (10) mils (175-250 microns) dries to a touch-dry (gel)
finish within three (3) hours at 72*F (22.2*C) and dries to a 70% cure in twelve
(12) hours. Cure times lengthen at lower temperatures and shorten at higher
temperatures.
14.0 Miscellaneous If the
mixed coating sits for more than two hours, the ceramic solids in CeRam-Kote
Ceramic Epoxy Coatings may settle out slightly. Shake or stir again. Shake one
(1) quart or two (2) quart systems by hand to ensure suspension of solids if
spraying is interrupted for more than an hour.
If coating is to be used in potable water, it is
recommended to high-pressure water wash the finished, cured coating with an
alkaline degreasing solution such as Devprep 88. After alkaline solution has
been applied per manufacturers instructions, rinse surface with fresh water.