Presentation on theme: "Corrosion under insulation (CUI)"— Presentation transcript:
1Corrosion under insulation (CUI) The Solution forCorrosion under insulation (CUI)
2Corrosion Under Insulation (CUI) CUI has been recognized as a problem in many industriesInsulation is a necessary component of the system and is designed to:Save energyControl process temperaturesProtect workers from high temperaturesNACE Standard SP is a good source of information, but electrolytes will eventually find their way into even the best system
3Anti-Corrosion Gel Performance Operating Temperatures – over 350° F/177 ° CMoisture Resistance – HydrophobicAnti-Corrosion Properties – Mineralization, Inhibitors & Buffering TechnologyApplicationSurface Prep – no sandblasting, free of oils/greasesCure Time – None, visual inspection easy and non-destructiveEquipment – Brush, PVC glove or sprayEnvironmentally benignCostTotal application cost is typically lower than other systemsLine shutdown not required
4TechnologyBarrier system – The specially formulated products have great adhesion characteristics (requiring minimal surface prep) and are hydrophobic to help keep moisture away from the substrate. Never cures thus microscopic air pockets don’t form.Mineralization - Growing an engineered surface, or surface conversion – creating a surface which resists corrosion even if moisture gets to it. Undercutting cannot occur.Buffering system – If moisture migrates through the gel through vapor drive, it is buffered to a high pH which is alkaline enough not to corrode metal. Gel also contains a number of corrosion inhibitors.
5How the reactive gel corrosion treatment works: When the ferrous (steel) surface (1) is covered with a layer of reactive gel (2), the metal surface reacts with components in the gel to form a mineral layer (3). This thin glasslike layer (3) acts as a barrier between chlorides and the metal surface, thus providing corrosion resistance.The mineral layer (3) has a thickness of angstroms, only 0.01% as thick as a piece of paper.
6Although the thin mineral layer can be damaged by mechanical abuse, there is extra protection built into the system, i.e.:• If the mineral surface is scratched or damaged, and there is residual gel in contact with the area, the mineral layer will be regenerated by the gel ingredients.• The gel contains a buffering agent, which raises the pH of water at the surface of the steel to 10 or above, a level unfavorable for corrosion of ferrous substrates. (Another formulation for aluminum adjusts the pH to 6-8).
8History of the Technology AutomotiveTechnology has been used in automotive applications for >30 years. Originates before Second World War.Crevice Corrosion on Brake CablesIndustrial ApplicationsFirst industrial application was with the US Navy. Solved their #1 and #2 corrosion maintenance problem.Watertight Door Latching MechanismsDeck Edge Elevator Wire RopesOther specific areas
92 Year Salt Water Immersion Test Samples in Aerated 5% salt solution
102 Year Salt Water Immersion Test Samples in Aerated 5% salt solution
112 Year Salt Water Immersion Test Non-Bead Blasted PipeBead Blasted Pipe
12Stress Crack Corrosion on SS Control Sample Typical Stress Crackingwith in 100 hours of exposurePer ASTM C 692EDC 2400 Treated SampleNo Cracking after 100 HoursExposure Per ASTM C 692Gel Treated SampleNo Cracking After 100 HoursExposure Per ASTM C-692
20Pipe temperature thickens the RG-2400 LT quickly Pipe temperature thickens the RG-2400 LT quickly. After 3 passes over an area it gets difficult to spread and achieve adhesion.The slight frost on the pipe left some voids, however fresh “warm” material could be put over these areas and achieve ahesion.INSTALLING RG-2400 LT
23CONCLUSIONSCOATING A 24° PIPE IN OPERATION IS POSSIBLE IN SMALL SECTIONS.RG-2400 MUST BE WARM TO IMPROVE COVERAGE AND EASE OF APPLICATIONINSULATION MUST BE INSTALLED IMMEDIATELY UPON ACHIEVING COVERAGE TO PREVENT CONDENSATION FROM FORMING ON THE RG-2400INSULRAP OR FABWRAP VAPOR BARRIER SHOULD BE USED TO KEEP OUT MOISTURETESTING WILL CONTINUE ON -15° F LINES IN OPERATION AND -50° F LINES IN OPERATION. RESULTS WILL BE ADDED TO THIS PPT PRESENTATION.GLYCOL WILL BE TESTED TO REMOVE FROST ON THE COLDER LINES.
24Product Application - Tank The tank was completely sprayed in approximately one hour
26Conoco/Phillips Well Casing WELLS WERE FIRST FLUSHED WITH 55 BARRELS OF 120° F CLEAN WATER TO REMOVE SLUDGE, WATER WAS PUMPED OUT AT END OF FLUSH CYCLE.
27Companies With Product Installations/specifications Anheuser BuschGeneral MillsJolly Green GiantBritish PetroleumBest Brands FoodsPhiladelphia GasFred Meyer FoodsUnocalDot FoodsExxon MobilCODELCOTuborgEfes PilsenGlaxoSmithKlineShellOxyChemErnst & GalloEquistarUnion CarbideCytecPhillipsMODOTNicorMonarch FoodsUS NavyKraft FoodsConocoPhillipsCoors BrewingCanada HydroIndiana University
28Benefits of the Technology: Practical application – simple non-curing gelMultiple delivery systems (spray, glove, brush)Insensitive to surface preparation and application conditionsDemonstrated superior anti-corrosion performanceEnvironmentally benignEasy to inspect