Thurmalox 218 Primer/219 Topcoat Coating Under Insulation (CUI) System

Wet/Dry Thermal Cycling to 450 F Apply Directly to Hot Steel

Thurmalox 218 Primer/219 Topcoat System are VOC compliant, high build, modified silicone coating formulated for the protection of metal surfaces under insulation exposed to temperatures from ambient to 450 F (232 C). This industrial pipe coating system is specifically formulated to be applied directly to hot steel having a metal temperature of up to 450 F (232 C) during application. Thurmalox 218/219 performs exceptionally in continuous immersion of hot and/or boiling water. It has excellent resistance to continuous and/or rapid wet-dry-wet thermal cycling to 450 F (232 C). Thurmalox 218/219 are durable, industrial pipe coatings able to withstand severe thermal shock as well as excellent chemical resistance.

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SKU: Thurmalox 218 Category:
  • Apply directly to metal surfaces as hot as 450 F (232 C)
  • Coat hot equipment without being shut down
  • Resistant to continuous immersion in ambient, hot and/or boiling water
  • High solid, high build
  • Excellent thermal cycling resistance
  • VOC compliant system
Generic TypePolymeric Compound
Mixing Ratio4:1 by volume
ColorLight Gray
Temperature Resistance Continuous1232C
Temperature Resistance Intermittent2260C
Volume Solids61 percentage
Dry Film Thickness Per Coat5.0 – 6.0 mils (125 – 150 microns)
Wet Film Thickness Per Coat8.0 – 10.0 mils (200 – 250 microns)
Theoretical Coverage Per Gallon978 mil. sq. ft.
Application Temperature at 50% RH71 to 232C
160 to 450F
Cure Time to Recoat at 50% RH34 hours
Cure Time to Re-insulate at 50% RH424 hours
Weight Per Gallon11.1lb
Pot Life2 hours
Shelf Life1 Year
V.O.C2.2 LBS/gal.
263 GMS./Liter
Only thin Thurmalox 218/219 coatings with Dampney 162 Thinner. Do not thin beyond federal, state and/or local VOC emission regulations.
Note: Use of other thinners not approved by Dampney may hinder product performance and void product warranty.
Clean Up
Thoroughly flush spray equipment and hoses immediately after use with Dampney 162 Thinner. Dismantle spray equipment and clean parts, brushes and rollers with Dampney 162 Thinner.
StorageStore in a cool, dry place with temperature between 50 F and 100 F (10 C and 38 C). Keep container closed when not in use.
1 Note 218 will change to amber color at 250 F (121 C). This is normal.
2 Note 218 will change to amber color at 250 F (121 C). This is normal.
3 A temperature of 160 F (71 C) must be achieved for the coating system to withstand hot/boiling water.
4 A temperature of 160 F (71 C) must be achieved for the coating system to withstand hot/boiling water.
Recommended Uses
  • Insulated hot equipment and piping
  • Insulated equipment exposed to severe thermal shock to 450 F (232 C)
  • Equipment under insulation exposed to wet-dry-wet cyclic conditions from ambient to 450 F (232 C)
surface Preparation
Carbon Steel
1. To ensure optimum long-term coating system performance, surfaces must be clean, dry and free from dirt, oil, grease, salts, welding flux, mill scale, rust, oxides, old paint, corrosion products or other foreign matter.
2. Remove all surface imperfections that will induce premature coating system failure. Chip or scrape off weld splatter. Grind down sharp and rough edges, gouges, and pits.
3. Abrasive blast surface per specification SSPC-SP 10, “Near-White Blast Cleaning”, or per NACE Standard No. 2 to a profile depth of 1.5 – 2.0 mils. Abrasive used in blasting should be selected carefully from materials of mesh size required to produce the desired anchor pattern.Applications Guidelines –
Surface temperature must be at least 5 F (3 C) above dew point.

Insulated Carbon and Stainless Steel – Maximum average DFT is 15-18 mils (375-450 microns).
Primer: Thurmatox 218 – 5.0-6.0 mils (125-150 microns)
Topcoat: Thurmatox 219 – 5.0-6.0 mils (125-150 microns)
Total dry film thickness – 10.0-12.0 mils (250-300 microns)

Stainless Steel
1. Surfaces must be clean and dry. Remove all oil, grease, soil, drawing and cutting compounds, and other foreign matter by methods outlined in Steel Structures Painting Council Specification SSPC-SP 1, “Solvent Cleaning”, using Dampney 170 Cleaning Solvent.
3. For large surface areas blast with “Starblast XL” (Starblast is a Dupont registered trademark) to achieve a surface profile of 1.5-2.5 mils. 4. For small surface areas, power sand following SSPC-SP 11, “Power Tool Cleaning”, using 16 or 24 grit aluminum oxide coated abrasive fiber disc attached to a rubber pad backer.

Applications Guidelines –
Surface temperature must be at least 5 F (3 C) above dew point.

Uninsulated Stainless and Carbon Steel – Total average DFT system is 15-18 mils (375-450 microns).
Primer: Thurmatox 218 – 5.0-6.0 mils (125-150 microns)
2nd coat: Thurmatox 219 – 5.0-6.0 mils (125-150 microns)
Topcoat Thurmatox 200 – 1.5-2.0 mils (35-50 microns)

Thurmalox 218 Primer and Thurmalox 219 Topcoat are two component coatings consisting of a Part A and Part B that must be mixed together before use. The mix ratio for Thurmalox 218 is 4:1 and that of Thurmalox 219 is 2:1 by volume. The individual component should be mixed separately to disperse pigment uniformly. Add Part B to Part A and mix thoroughly with a low-speed power mixer for a minimum of 3 minutes or until mixed coating is completely blended and of uniform color.
Application Equipment
Thurmalox 218/219 coatings may be applied by Conventional and airless spray

Conventional Spray:
Spray gun – DeVilbiss JGA402 or equal
Fluid tip – EF
Air Cap – 704
Fluid hose – 3/8″ ID – Smaller hose diam. or length over 25 ft. may require increased pressure.
Air hose – 5/16″ ID
Atomizing pressure – 60 psi
Provide material pot with agitator, regulators for fluid and air pressure, and oil and moisture traps in supply line.

Airless Spray:
Spray gun – Graco 205-591, 208-663
Fluid tips – 163-610, 163-315 – Use Reverse-A-Clean tips for fast, easy clean out.
Pump – Graco Bulldog 30:1
Fluid hose – 3/8″ to 1/2″ ID
Air pressure to pump – 100 psi
Pump operating pressure – 80-90 psi

Procedures for Application to Hot Surfaces
1. Flush spray equipment with Dampney 162 Thinner before use.
2. Thinning of Thurmalox 218/219 coatings is not normally required for spray application.
3. Dampney 162 Thinner is a high flash point (102 F), slow evaporating solvent formulated especially for application to hot surfaces.
4. WARNING DO NOT use any other solvents to thin Thurmalox 218/219 coatings. A fire hazard may result from use of solvents with low auto ignition temperatures when applying Thurmalox 218/219 coatings to hot surfaces, and rapid solvent evaporation can cause dry spray and poor film characteristics.
5. Use Dampney 162 Thinner cautiously. Addition of a small amount of thinner will cause a great reduction in coating viscosity. Excessive thinning will cause runs or sags.

For conventional spray use adequate air pressure and volume to obtain proper atomization. Be aware that procedures for applying coatings to hot surfaces are somewhat different from those normally used for application to ambient temperature surfaces.
The following factors should be taken into consideration:
a) Heat radiating from the surface and/or strong winds will promote dry spray.
b) To avoid dry spray, always apply coatings perpendicular to hot surfaces without reaching.
c) Perpendicular spraying will also minimize overspray and lap marks.
On each pass of the spray gun a thinner than normal paint film must be applied to facilitate the heat-accelerated escape of solvents without leaving pinholes.

Cure Time 160 F (71 C) 50% RH
Thurmalox 218/219 Coating System will cure within 8 hours. Allow 4 hours dry time between coats. A temperature of 160 F (71 C) must be achieved for the coating system to withstand hot/boiling water. Higher application temperature will reduce cure time.
Precautionary Information
WARNING: Flammable Liquid and Vapor Keep away from heat, sparks and flame. Vapors may cause flash fire. Do not breathe vapors or spray mist. Avoid contact with eyes, skin and clothing. Use with adequate ventilation during mixing and application. Wear an appropriate, properly fitted organic vapor cartridge-type respirator (NIOSH approved) during and after application unless air monitoring demonstrates vapor/mist levels are below applicable limits. Follow respirator manufacturers directions for respirator use. Wash thoroughly after handling. Wear protective gloves, chemical safety goggles and impervious protective clothing. Use skin cream. In confined spaces it is required to use a positive pressure supplied-air respirator (NIOSH approved). Use explosion-proof lights and electrical equipment. Use only nonsparking tools and equipment. Wear conductive and nonsparking footwear. Make certain all electrical equipment is grounded. Observe all safety precautions and follow procedures described in OSHA regulations. See Material Safety Data Sheet (MSDS) for complete precautionary and disposal information.

If instructions and warnings cannot be strictly followed, do not use this product.

For industrial use only

Dampney protective coating products are expressly warranted to meet applicable technical and quality specifications. The technical data contained herein are accurate at the date of issuance but are subject to change without prior notification. No warranty of current accuracy is hereby given or implied. User must contact Dampney to verify correctness before ordering. Dampney assumes no responsibility for coverage, performance or injuries resulting from handling or use and LIABILITY, IF ANY, SHALL BE LIMITED TO PRODUCT REPLACEMENT. In no event will Dampney be responsible for consequential damages, except insofar as mandated by law. Dampney DISCLAIMS ALL OTHER WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.

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