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Reduce liability of premature coating failure by recognizing and eliminating soluble salts. Learn about sources, testing methods, and the impact on coating economics. Discover Steelshield RTT-3 for effective corrosion prevention.
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Understanding Salts 101 Rugged Terrain Technologies, LLC A special presentation
Awareness • Recognition • Elimination Objective:Reduce liability of premature coating failure. Goal: Achieve full life cycle coating performance.
What are Soluble Salts? • Ionic contaminants • Water soluble inorganic compounds • Primarily chlorides, sulfates and nitrates • Non-visible contaminants
Sources of Salts • Marine environments • Environmental fallout • Chemical plants • Deicing salts
Salts: Osmosis and Permeation Coating failures resulting from salt induced corrosion
Salt removal during Surface PreparationWhy? • Salts are a leading cause of coating failure today. • ~80% of coating failures due to salts • Visual standards used are insufficient. • Visual standards were adequate for lead paint applications.
Pack rust Coating failure Corrosion products Metallic pathway Cathode Anode Electrolyte
Testing for Salts Two parts: • Extractions • Analysis
Analysis methods Two distinct methods: • Conductivity – measures all conductive constituents. • Ion specific – measures the specific ion of concern; chloride, sulfate, or nitrate.
Conductivity Method • Measures everything conductive in the sample. • Many species are not detrimental to the coating film nor induce premature coating failure. • Measures all minerals. • Conversion to chloride level is an estimate. • Assumes a lab correlation based on 100% chlorides. • Conductivity and reactivity are different.
Ion specific method: • Measures the specific problematic ion. • Can measure different ions – chlorides, sulfates, and nitrates. • Reagent liquid chemicals can measure chlorides, but usually result in a range ( > to < ). • Field testing • 1. CHLOR*TEST for chlorides • 2. CHLOR*TEST ‘CSN’ for chlorides, sulfates and nitrates. • 3. CHLOR*TEST ‘W’ for water (or chemicals)
CHLOR*TEST Components
Quantitative Accuracy Source: KTA Laboratories
Bonding strength Why are salts left behind if they are water soluble? The electrochemical attachment of salts to the substrate are greater than the forces applied to remove them.
Coatings Economics Goal: Achieve lowest cost/ft2/yr for the expected coating life Based on actual experience by NAVFAC since instituting revised specifications in 1995.
STEELSHIELD RTT-3 Corrosion Preventative Primer …Has the Unique Ability to Create an Ionic Bond With The Metal and Contains Oxygen Scavenging Properties Which Prevent Corrosion From Ever Taking Root
Thank You! For further information: www.bryantfuelsystems.com