SUCCESSFUL METHODS FOR MITIGATION OF CORROSION UNDER INSULATION (C.U.I.) AND OTHER CREVICE CORROSION USING

SURFACE CONVERSION TECHNOLOGY

Patrick J, Dunn Sr.Vice President – Mechanical Products Division

Polyguard Products, Inc.P.O. Box 755

Ennis, Texas 75120

pjd@polyguardproducts.com

Corrosion Under Insulation (CUI)

CUI has been recognized as a problem in many industries Insulation is a necessary component of the system and is

designed to: Save energy Control process temperatures Protect workers from high temperatures

NACE Standard RP0198-981 is a good source of information, but electrolytes will eventually find their way into even the best system

Corrosion Under Insulation

Selecting the Correct Coating System Performance

Operating Temperatures Moisture Resistance Anti-Corrosion Properties

Application Surface Prep Dry/Cure Time Labor & Equipment Requirements

Total Cost Product Application Ease of Maintenance Comparison of TOTAL installed cost is recommended

Anti-Corrosion Gel Performance

Operating Temperatures – up to 350° Moisture Resistance – Hydrophobic Anti-Corrosion Properties – Mineralization & Buffering

Technology Application

Surface Prep – SP-2 or better Dry/Cure Time - None Labor & Equipment Requirements - Minimal

Cost Installed cost is typically lower than other systems

Technology

The technology works in three basic ways Barrier system – The specially formulated products have

great adhesion characteristics and are hydrophobic to help keep moisture away from the substrate.

Mineralization - Growing an engineered surface, or surface conversion – creating a surface which resists corrosion even if moisture gets to it .

Buffering system – If moisture migrates through the gel, it is buffered to a high pH which is alkaline enough not to corrode metal.

Basic Science

Metal surface:OxidesMetal carbonatesMetal hydroxides

METAL

Polymerized metal silicate lattice

METAL

Protected surfaceExtended surfaceMineral formation

METAL

Metal surface

METAL

Surface conversion technology, also known asmineralization, is the ability to grow very thin minerals onmetal surfaces. The mineral forms when reactants aredelivered to the surface of a metal or metal containingarticle. Substrates contribute ions that form a thin layer ofmineral, which chemically bonds to the surface of the metaland has been measured to be 50-200 angstroms thick.Lattice-forming oxides anchor to this surface layer andpolymerize into a three-dimensional inorganic frameworkuntil the final surface is formed.

Patents and patent applications cover unique formulationsas well as the mineralized layer that is formed.

Surface FormationUntreated steel surface Mineralized steel surface

10 um 10 um

The presence of the mineralized layer can be confirmed byconventional analytical surface methods such as x-rayPhotoelectron Spectroscopy (XPS) or Atomic ForceMicroscope (AFM)

• Automotive– Technology has been used in automotive applications for

approximately 30 years. – Crevice Corrosion on Brake Cables

• Industrial Applications– First industrial application was with the US Navy. Solved their #1 and #2

corrosion maintenance problem.– Watertight Door Latching Mechanisms– Deck Edge Elevator Wire Ropes

History of the Technology

11

2 Year Salt Water Immersion Test

Samples were prepared with fiberglass pipe insulation, surface conversion gel technology and placed in a 5% aerated salt bath.

2 Year Salt Water Immersion Test

Samples were removed at timed intervals to determine protection of substrate

10 DAYS

81 DAYS

138 DAYS

365DAYS

13

2 Year Salt Water Immersion Test

TWO YEAR IMMERSION55mil PER YEAR CORROSION RATE

14

2 Year Salt Water Immersion Test

One uninsulated pipe in the test proved that the Gel does not undercut

Undercutting Test2000 hrs

ASTM B117 Salt SprayGel Protected Steel Panel

2000 hrs ASTM B117 Salt Spray

Gel Removed

One unique property of gel surface conversion technology is that the gel will not undercut like a hardening barrier coating will.

16

Isothermal Testing

17

Weight Loss Testing

Corrosion Under Insulation (CUI)

Corrosion Under Insulation (CUI)Ammonia Piping Remediation

CUI - North Slope 2003

CUI - North Slope2010 Inspection

CUI – Bundled PipeCorrosion Remediation of Bundled Pipe System (BIR)

CUI – Bundled Pipe (BIR)

X-Ray Inspection Through Insulation

CUI – Bundled Pipe (BIR)

Remove Metal Jacket

Remove Insulation

CUI – Bundled Pipe (BIR)

Removal of Aged Mastic

CUI – Bundled Pipe (BIR)

Physical Inspection of Pipes

Removal of Rust Scale with wire brush and pot scrubber

CUI – Bundled Pipe (BIR)

Install of Corrosion Gel

Uniform Thickness Trowel

CUI – Bundled Pipe (BIR)

Install Stand-offs and Insulation

Install Metal Jacketing

DOWNHOLE CORROSION PROTECTION

Benefits of the Technology:

Practical products and applications Multiple delivery systems Ease of application Insensitive to surface preparation and application

conditions (SP-2 Hand Tool Cleaning or better) Superior anti-corrosion performance Environmentally benign Easy to inspect

Companies With Product Installations• OxyChem• Equistar• Union Carbide• Cytec• Phillips• MODOT-Missouri Dept of Transportaton• Nicor• Tesoro Refinery• Monarch Foods• Safeway• U.S. Navy • Kraft Foods• Dow Chemical• Schepps Dairy• ConocoPhillips - downhole• Coors Brewing• Canada Hydro• Indiana University – Chiller Pipe• Southgate Foods• Wal-Mart• Scotia Bank Toronto (CHW)• Shepps Dairy• Chevron

• Budweiser• General Mills• Nestle• Green Giant• British Petroleum• Best Brands Foods• Philadelphia Gas• Fred Meyer Foods• Unocal – AK Oil Platforms• Dot Foods• ExxonMobil

-Sakhalin Island Steam Lines Phase IPhase II

-Downhole Wells Alaska• Alta-Dena Dairy• Conagra• Tyson Foods• Tyson Chicken• Tyson Fresh Meats• Kroger• US Cold Storage• Publix Grocers• Tombstone Pizza

The entities listed above have used and/or specified surface conversion technology on one or more projects, however, the naming of these entities do not imply advertisement or public endorsement of the product.