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Accelerated corrosion problems in today’sinfrastructure and a greater awareness ofcorrosion issues, require demanding and
viable long-term solutions.
Corrosion will increase due to:
– Reduction of inflow and infiltration– Regulatory changes in pre-treatment– Expansion of collection systems
EPA/625/6-91/030
THIRD PARTY COATINGS & LININGSRESOURCE PROPERTIESLos Angeles County Sanitation Ease of Application
Chemical ResistanceBond Inspection
Greenbook - City of Los Angeles Chemical ResistanceChange in Physical Properties
Trenchless Technology Center Buckling StrengthHydrostatic Pressure Effects
ASTM Independent Testing PermeabilityTensile/Flexural/Compressive PropertiesChemical Resistance
Material Safety Data Sheets Safety & Handling
Others: NACE, SSPC, and Universities Across North America
Can Help Prevent:
• Polymer Coating and Liner Disbonding• Aggressive Corrosion• Pinholes• Thinner Than Specified Coating Applications• Roots and Infiltration
CORRECT PRODUCT SELECTION,INSTALLATION & INSPECTION
HOW DO WE SELECT THE CORRECT COATINGOR LINING SYSTEM ?
Thermoplastic sheet liners Cementitious systems
Polymer Systems
STRUCTURAL & NON-STRUCTURALRENEWAL OPTIONS
• Cementitious Coatings (Portlandto Calcium Aluminates')– Structural-1/2”- 4”– Non-Structural-3/8”-1/2”
• Polymer Coatings (Epoxies andPolyurethanes)– Structural-125-500 mils (1/8” –
1/2”)– Non-Structural-60 mils
minimum-100 mils average• Composite Systems
CORROSION PROTECTIONOPTIONS
• Cementitious formulations– Calcium aluminate– Antimicrobial additives
• Thermoplastic linings– Cement or polymer
mastic basecoat• Polymer coatings
– Epoxies,polyurethanes,
polyureas
COATING THICKNESS• New surface (Corrosion Resistance or Chemical Protection)• Profile Height• Effects of hydrostatic head pressure or water vapor transmission
(Design with ASTM 1216-07 for Structural Applications)• Environment
UNDERGROUND INSTALLATIONVARIABLES
• Temperature and humidity• Moisture filled substrates• Hydrostatic pressure• Water vapor transmission• Surface and structure
condition• Accessibility and confined
space
KEY FACTORS FOR PREP SUCCESSObtain a clean, dry and sound surface!
• Understandpreparationprocedures
• Understand repairprocedures:– infiltration or
substrate loss• Know how to test
preparationresults
• Know commonmethods of:– cleaning power– abrasive
choices– coating
removal
COATINGINSPECTION PARAMETERS
• Substrate inspection• Ambient conditions• Surface profile• Surface cleanliness• Mixing procedures• Application
procedures
SAMPLE FORM Quality Assurance/Quality ControlContract Name: __Manhole Rehabilitation ____________________________________ Contract No: _________________________Contractor/Installer: ___________________________ Construction Observer/Inspector: _____________________________Report No.__________ Weather:______________________________ Structure Temp: Ambient___________ Surface_____________Other Work in Progress: ____________________________________________________________________________________________
InspectionPerformance Acceptable Results
No. Quality Assurance Standard Quality Quality Control Pass/Fail Comments
1
Visual inspection of structuresubstrate after cleaning and
preparationIndustryStandard 100%
Visually inspect surfaces to be coated foreffective removal of existing coatings, unsoundsubstrate, laitance, infiltration. Visually identify
prob lem areas.
2 Test substrate for soundness.
SSPC- SP13 NACE
No. 6 100%
Lightly scratch prepared concrete surfaces with ascrewdriver or pocket knife. The scratch shouldleave a shiny mark with no loose particles fromthe surface. Otherwise, re-prep and re-inspect.
3
Visual inspection of productapplication and documentation of
proper material ratio/usage
ProductTechnical Data
Sheet (ratio) 100%
Visually observe mixed color which should behomogenous without marb ling effect. Inspectionrecordkeeping of applicator for material usage of
product components, verify proper usage.
4
Wet Film Thick ness (WFT)measured during application. NOTE:
When applying fast settingpolyurethanes, this test is not
applicable. Use the adhesion test toalso measure mil thickness. ASTM D-4414
No lessthan 90% orgreater than
120%
Measure and record the WFT in at least fourlocations for every 500 sf and each coat of
material applied.
5Holiday Detection using a high
voltage holiday detector.NACE RPO-
188 100%
Confirm conductivi ty by inducing holiday andcalibrating detector. Test entire coated surface.
Repair and retest as required.
6
Adhesion Testing using a ElcometerModel 106 on a minimum of 10% of
the manhole structures coated. ASTM D-4541As
specified
Perform a minimum of three pull tests permanhole at locations randomly selected.
Evaluate results and repair coating where tested.
Record dolly location, pullstrength (psi), mode of failureand whether dolly was scoredor unscored.
Owners Representative: Name Signature Date
Contractor/Installer Representative: Name Signature DateAll QA/QC as per specific manufacturer's recommendations.
QUALIFIED CONTRACTORS>90% of all failures result from improper installation!
Contractor Requirements– Certification of Training
• Manufacturer• Third party• NACE (National Association of Corrosion Engineers)
• SSPC (Steel Structures Painting Council)
– Experience• Similar scope, size or training• Time period
• Established manufacturersthat implement QC duringmanufacturing (ISO 9000)
• Suitable for application inspecified environment
• Capable of providingprotection and/or structuralneeds
• Field tested and proven
Quality Control - Materials
EQUIPMENT• Equipment is product
dependent• Some can be
mobilized intoundergroundstructures asnecessary
• Efficiency andproduction varies
VISUAL INSPECTION
• Cracking, pinholes, exposedsubstrate
• Proper bench and invertrebuild
• Frame/chimney sealing• Pipe joint seals• Step removal or replacement
MONOLITHIC INSTALLATIONHoliday (Spark) Testing
A barrier without fault provides effective long-termelimination of infiltration and corrosion protection
ADHESIONA verifiably acceptable mechanical bond to the host structure is essential for
long-term performance.
NOTE: USE MODIFIED ASTM D4541 AND EXPERIENCED INSPECTORS
A CLEAN AND DRY SURFACEWILL PROVIDE OPTIMAL RESULTS !
REMEMBER THE SEVENREMEMBER THE SEVEN PPs!s!Performance Specifications-Tight & With Stringent QA/QC
Proven Products & Correct Selection
Proper Preparation Of Surface & Coating With Certified,Trained & Experienced Applicators
With Use Of The Above Guidelines, You Will Discover That
Perfect Performance For A Longer Term Is Virtually Guaranteed