Protecting Georgia Transmission Protecting Georgia Transmission Companies weathered Companies weathered

galvanized and previously galvanized and previously painted transmission and painted transmission and

substation structuressubstation structures..

Back to the FutureBack to the Future

►Oldest surviving basic technology to still be Oldest surviving basic technology to still be sole-sourced since 1955. Many high-sole-sourced since 1955. Many high-performance coatings developments are performance coatings developments are tied to significant cleaning and surface tied to significant cleaning and surface preparation requirements, which preparation requirements, which sometimes trigger extreme controls on sometimes trigger extreme controls on environmental costs (full-containment) and environmental costs (full-containment) and other expensive requirements. Lowest cost other expensive requirements. Lowest cost per square foot per year @ 20-30 years life.per square foot per year @ 20-30 years life.

Linseed Oil Wetting and Linseed Oil Wetting and PenetrationPenetration

Essential Properties of Essential Properties of CoatingCoating

►Maximum wetting and penetration into Maximum wetting and penetration into tight corroded spaces.tight corroded spaces.

►High-build; 9- 11 mils WFT in one coat= High-build; 9- 11 mils WFT in one coat= 8-10 mils DFT.8-10 mils DFT.

►Easy to apply by mitt or pound brush.Easy to apply by mitt or pound brush.►Maximum barrier properties to resist Maximum barrier properties to resist

moisture, airborne chlorides, moisture, airborne chlorides, chemicals, air pollutants, and ultra-chemicals, air pollutants, and ultra-violet light.violet light.

Candidate Coatings For Candidate Coatings For StructuresStructures

►Modified Linseed-Oil Zinc-Dust.Modified Linseed-Oil Zinc-Dust.►Modified Linseed-Oil MIO/Zinc-Dust.Modified Linseed-Oil MIO/Zinc-Dust.►Modified Linseed-Oil MIO/Zinc-Dust, Modified Linseed-Oil MIO/Zinc-Dust,

Aluminum, and Ceramic Microspheres.Aluminum, and Ceramic Microspheres.►Aluminum Epoxy Mastics.Aluminum Epoxy Mastics.►Calcium Sulfonate Alkyds.Calcium Sulfonate Alkyds.►Epoxy Penetrating Sealers.Epoxy Penetrating Sealers.

Benefits of Penetrating Benefits of Penetrating SealersSealers

►Tie-down existing old coatings; wick Tie-down existing old coatings; wick under loose edges and into tight under loose edges and into tight crevices.crevices.

►Very low viscosity.Very low viscosity.►No curing stresses that pull off old No curing stresses that pull off old

coatings.coatings.►100% SBV100% SBV►Tougher and more moisture and Tougher and more moisture and

chemical resistant than alkyd primers.chemical resistant than alkyd primers.

MIO as Barrier PigmentMIO as Barrier Pigment►Chemically Inert and very resistant to Chemically Inert and very resistant to

pollution.pollution.►Does not react with high or low pH. (acid Does not react with high or low pH. (acid

and alkaline resistant)and alkaline resistant)►Labyrinth Effect and Shielding from UV, Labyrinth Effect and Shielding from UV,

pollution, and especially moisture.pollution, and especially moisture.►Absorbs UV and warms the coating; hence Absorbs UV and warms the coating; hence

drying.drying.►Promotes adhesion to substrate and itself.Promotes adhesion to substrate and itself.

MIO: 100 Years of SuccessMIO: 100 Years of Success

► Is Is Non-Toxic, Non-Oxidizing, Non-Non-Toxic, Non-Oxidizing, Non-Corrosive & Non-FlammableCorrosive & Non-Flammable. With . With such excellent chemical & environmental such excellent chemical & environmental properties, it is not a surprise that it is the properties, it is not a surprise that it is the world’s most favored barrier pigment for world’s most favored barrier pigment for over 100 years. Formulators consider MIO over 100 years. Formulators consider MIO to be a key weapon in their anti-corrosive to be a key weapon in their anti-corrosive arsenal. arsenal.

MIO as Barrier PigmentMIO as Barrier Pigment

►Improved mechanical properties.Improved mechanical properties.►Less crackingLess cracking►Tougher coating all around.Tougher coating all around.

Properties of Ceramic Properties of Ceramic MicrospheresMicrospheres

►Reduces Undercutting and Reduces Undercutting and improves resistance to cathodic improves resistance to cathodic disbondingdisbonding

►Enhances Film-Build and especially Enhances Film-Build and especially edge retention on towers.edge retention on towers.

►Lowers Permeability of the paint Lowers Permeability of the paint film.film.

CompositionComposition

Ceramic BeadsHydrophobic Carbon

SUBSTRATE

Modified Linseed Oil Alkyd Binder

Minimal SolventMinimal VOC’s

No Haps

Tower FootingsTower Footings► 1930s and 1940s: Dipped in hot tar. No 1930s and 1940s: Dipped in hot tar. No

longer specified. Under-film corrosion. longer specified. Under-film corrosion. Coal-tar epoxy used in 1960s-1980s. Not Coal-tar epoxy used in 1960s-1980s. Not often specified; also strong cohesion vs. often specified; also strong cohesion vs. sub-film corrosion. Results improved when sub-film corrosion. Results improved when 110 micron HDG was increased to 200 110 micron HDG was increased to 200 microns. More awareness of conductivity microns. More awareness of conductivity (soil resistivity) pH values, types of soils, (soil resistivity) pH values, types of soils, et. al.. 0.5 mm zinc plates welded to tower et. al.. 0.5 mm zinc plates welded to tower legs on all sides. legs on all sides.

Tower Footing HistoryTower Footing History► Zinc plates welded plus hot tar dips.Zinc plates welded plus hot tar dips.► Tapes used 1955-1980s: Freeze-thaw Tapes used 1955-1980s: Freeze-thaw

issues.issues.► Copper earth mats: tower leg becomes the Copper earth mats: tower leg becomes the

anode= 500 microns per year of corrosion.anode= 500 microns per year of corrosion.►Moisture-cured coal-tar urethanes Moisture-cured coal-tar urethanes

frequently used today (limitations on frequently used today (limitations on surface preparation costs and time)surface preparation costs and time)

Shop Painted Transmission PolesShop Painted Transmission Poles

Substation EquipmentSubstation Equipment

WHAT MAKES SUBSTATION WHAT MAKES SUBSTATION PAINTING UNIQUE?PAINTING UNIQUE?

► SURFACE PREPARATIONSURFACE PREPARATION► FLOW COATINGFLOW COATING

►Maintain viscosityMaintain viscosity►Apply uniform 2.5-3.0 mils dft along Apply uniform 2.5-3.0 mils dft along

entire length of radiatorentire length of radiator

► SAFETY IN A HIGH VOLTAGE SAFETY IN A HIGH VOLTAGE ENVIRONMENTENVIRONMENT

WHAT MAKES SUBSTATION WHAT MAKES SUBSTATION PAINTING UNIQUE?PAINTING UNIQUE?

► SURFACE PREPSURFACE PREP► FLOW COATINGFLOW COATING

►Maintain viscosityMaintain viscosity►Apply uniform 2.5-3.0 mils dft along Apply uniform 2.5-3.0 mils dft along

entire length of radiatorentire length of radiator

► SAFETY IN A HIGH VOLTAGE SAFETY IN A HIGH VOLTAGE ENVIRONMENTENVIRONMENT

► COATING SELECTIONCOATING SELECTION

WHAT MAKES SUBSTATION WHAT MAKES SUBSTATION PAINTING UNIQUE?PAINTING UNIQUE?

► SURFACE PREPSURFACE PREP► FLOW COATINGFLOW COATING

►Maintain viscosityMaintain viscosity►Apply uniform 2.5-3.0 mils DFT along Apply uniform 2.5-3.0 mils DFT along

entire length of radiatorentire length of radiator

► SAFETY IN A HIGH VOLTAGE SAFETY IN A HIGH VOLTAGE ENVIRONMENTENVIRONMENT

► COATING SELECTIONCOATING SELECTION

SUBSTATION EQUIPMENT SUBSTATION EQUIPMENT COATING SYSTEMCOATING SYSTEM

►Full prime Body Full prime Body Induron’s P-30 Primer Red Induron’s P-30 Primer Red

►Full Intermediate CoatFull Intermediate CoatInduron’s P-30 Primer TanInduron’s P-30 Primer Tan

►Full Finish CoatFull Finish CoatInduron’s Indurasil Silicone Induron’s Indurasil Silicone

EnamelEnamel