1. An investigation of how good specifications prevent coating failures
Abstract:  This webinar presents a scientific approach to the analysis and prevention of common paint and coating failures on industrial structures. It begins with a close look at the structure, composition and properties of polymers used in the formulation of modern paints and coatings, followed by a systematic consideration of failures induced by weather, corrosion, mechanical and chemical influence, light, heat, and other agents. 

2. Prevent Coating Failures
Corrosion Protection
Good Design
Good Paint
Good Specifications
Good Contractors
Good Inspection
Good Maintenance

3. NATURAL CYCLE OF CORROSION
Iron ore
Corrosion / Rust
Exposure
Blast Furnace
Steel (Iron) Plate

4. FOUR CONDITIONS NECESSARY FOR CORROSION
An ANODE (Oxygen reacts with Iron)
A CATHODE (Oxygen + water react)
An ELECTROLYTE (Source of Ions)
A CIRCUIT connecting the Anode
and Cathode (Moisture)
Section 1 - Understanding the Science of Corrosion

5. COATING INTERRUPTS CORROSION
Paint is a BARRIER that can stop the flow of electrical currents.
Section 1 - Understanding the Science of Corrosion

6. Prevent Coating Failures
Corrosion Protection
Good Design
Good Paint
Good Specifications
Good Contractors
Good Inspection
Good Maintenance

7. Examples of Design Problems
Back to Back Angles
Channels Turned Up
Too Close to Headwalls (Deck)
Skip Welds
Poor Bolt (Rivet) Spacing
Limited Access

8. BACK – TO – BACK ANGLES

9. CHANNELS TURNED UP

10. TOO CLOSE TO HEADWALLS

11. SKIP WELDS

12. POOR BOLT (RIVET) SPACING

13. LIMITED ACCESS

14. Prevent Coating Failures
Corrosion Protection
Good Design
Good Paint
Good Specifications
Good Contractors
Good Inspection
Good Maintenance

15. DEFINITIONS Coatings LININGS
A layer of a substance spread over a surface for protection or decoration.
LININGS
A covering or coating for an inside surface.
Something that is used to line another thing; a layer of material on the inner side or surface of something.

16. DEFINITION Coating System
The application of a number of coats, separately applied, in a pre-determined order and thickness, with suitable intervals to allow for drying or curing.
Finish – uv/esthetics
Intermediate – barrier coat
Primer – corrosion inhibitor
steel

17. COATING THICKNESS Measured in Thin Film (< 20 mils or 500 microns)
mils (thousandths of an inch)
Microns (24.6 microns per mil)
Thin Film (< 20 mils or 500 microns)
Thick Film (>20 mils)
Example – Copy paper is typically 4-5 mils thick

18. GOOD PAINT Two Specifying Methods
Formula / Design (decreasing in popularity)
Performance
Reputation
Laboratory Testing
Weighting Factors

19. GOOD PAINT FORMULA / DESIGN SPECIFICATION
A Formula/Design specification provides in-depth detail about the coating formulation.
It provides the user with all of the information and references necessary so they can achieve the intended outcome. The design specification result should be consistently reproducible providing the same standard outcome
Provides specific instructions

20. GOOD PAINT PERFORMANCE SPECIFICATION
Reputation
Case histories of coating systems on similar structures

21. GOOD PAINT PERFORMANCE SPECIFICATION
Laboratory Testing
NTPEP data available online
Exposures:
Salt Fog
Cyclic Weathering (cycles = 1 week prohesion / 1 week QUV)
Tensile (Pull-off) Adhesion
Freeze Thaw Stability

22. GOOD PAINT PERFORMANCE SPECIFICATION
Weighting Factors:
Coating System must be matched to the service environment
Guidance available:
SSPC “Selecting Materials for Industrial and Marine Structures”
NORSOK M-501

23. COATING SYSTEM
A coat is a single application (one layer) applied to form an evenly distributed film when dry.

24. COATING SYSTEM Common system terminology Primer Stripe Coat
Intermediate
Finish

25. PRIMER First coat applied
Contains ingredients which provide for adhesion to the substrate.
Provides for subsequent coats
Dictates the degree of cleanliness required of the substrate.
May provide anti-corrosion properties

26. STRIPE COAT Not always required
Provide additional coating in sensitive areas
Cervices
Welds
Sharp edges
Fasteners
Commonly brush applied

27. INTERMEDIATE Not always required May improve chemical resistance.
May be a “Tie Coat” between the primer and finish coat when not compatible.
Increase the film thickness.

28. TOP COAT / FINISH Last coat applied May improve chemical resistance.
May provide for:
Color
Gloss
Mildew resistance
Wear resistance (hardness)
Critical that each coat in a multi-coat system be different colors/tinted for easy identification during the inspection process.

29. CORROSION PROTECTION Provided by Protective Coating Systems through
BARRIER PROTECTION
INHIBITIVE
GALVANIC
May incorporate combinations of the above.

30. BARRIER PROTECTION
The partial blocking of any or all elements by a semi-impermeable film.
Examples: Tank Linings, Ballast Tanks

31. INHIBITIVE - INHIBITION
Slowing down of the corrosion reaction by passivation of the substrate
Primers
Red Lead, Chromates

32. GALVANIC - SACRIFICIAL
Pigment is anodic to the substrate and corrodes in preference to the steel
Cathodic Protection
Most common: Zinc rich primers

33. COATINGS Are classified by their methods of film formation or cure.
The curing mechanism for a generic category of coating is the method or reaction causing the liquid coating to convert into a solid membrane which is resistant to that particular environment.

34. COATINGS
The method of cure may effect and/or require a specific mixing requirement, timing or “Sweat-in Time”, or have specific environmental/ambient condition requirements during the application process.

35. CURING MECHANISMS Oxidation Evaporation Chemical Reaction
Hydrolysis or Hydration
Coalescence

36. OXIDATION Reacts with the oxygen and allowed to polymerize or harden.
One component material
Typically an oil modified, solvent-based coating.
Used in mild environments
Poor chemical resistance
Poor solvent resistance

37. OXIDATION
Good penetration into and around irregular surfaces and/or poorly prepared surfaces.
Drying oils
Alkyds
Silicone alkyds
Epoxy esters

38. EVAPORATION
Allows the liquid coating to stay in-place long enough for the liquid carrier or solvent to evaporate and the solids to become hard.
The resins are dissolved within the solvent during the manufacturing process.
Typically used as intermediate and finish coats.

39. EVAPORATION Good chemical resistance Limited solvent resistance
Dries at low temperatures
Dries very quickly
Chlorinated rubbers
Vinyls

40. CHEMICAL REACTION
Is curing that results from a chemical reaction between the resin and the curing agent (activator) to form a hard film.
Small molecules form into large molecules.
May require an “Induction” or “Sweat” time prior to application.
Limited pot-life

41. CHEMICAL REACTION Temperature sensitive Humidity sensitive
to low: incomplete cure
to high: reduced pot-life
Humidity sensitive
Good chemical and solvent resistance
Epoxies (will chalk when exposed to UV)
Urethanes

42. HYDROLYSIS or HYDRATION
Hydrolysis is the taking of moisture from the air to produce a hard film.
Solvent-based inorganic zinc-rich primers and certain urethanes.
Inorganic zinc-rich primers involve a two-step process. First evaporation takes place with the solvent and a reaction takes place between the zinc and binder. The film is dry, although until the film reacts with moisture in the air, it is not cured.

43. COALESCENCE
A combination of evaporation of water and coalescence of particles of polymers.
Higher concentrations of solids
Latex, Acrylics

44. RECENT TECHNOLOGIES Fluoropolymer Coatings
Exceptional resistance to solvents, acids, and bases.
Longer life in terms of color retention and gloss over traditional urethanes.
Typical costs per gallon of >$400.00

45. Premature Coating Failures
Common Failure Mechanisms
UV degradation (color, gloss reduction, chalking)
Osmotic blistering
Cathodic delamination
Corrosion
Poor adhesion
Chemical attack
Abrasion

46. UV degradation (color, gloss reduction, chalking)
Cause: Exposure to sunlight
Resistance to UV degredation:
Polymers with more stable bonds such as siloxanes and fluoro carbons
Need polymers which do not have unsaturation, i.e. no carbon-carbon double bonds, aromatic groups, etc.
UV resistance can be enhanced by adding hindered amine light stabilizers (HALS) and UV absorbers
Need to use light stable pigments.
Example Rutile TiO2 is light stable (especially with silica and alumina coating) while Anatase TiO2 is not stable.
Susceptible to UV degredation:
Examples: epoxies, aromatic isocyanates and alkyds (have unsaturation in their polymers)
Consider laboratory QUV exposure data

47. Osmotic blistering Causes:
water soluble ionic compounds or water soluble covalent compounds remaining on substrate
Coating moisture permeability
Make sure the surface is clean from water soluble ionic compounds or water soluble covalent compounds.
Specify desired surface cleanliness

48. Corrosion 4 sources of common corrosion: Erosion induced corrosion
The coating wears away due to weathering effects until the substrate becomes exposed to the elements.
Rates of erosion and relative costs of common coatings:
Alkyd > Epoxy > Polyurethane > Polysiloxane > Fluoropolymer
Damage induced corrosion
Scratching/Cutting of films to the substrate
Impact and breakage of the film
Cracking of films due to excessive thickness and temperature variations
Conductive pathway induced corrosion
Microscopic pathways in the coatings film which may allow ions to transport to the steel substrate.
Contamination induced corrosion
Corrosion resulting from contaminants (ions and water solubles) residing on a substrate that has been overcoated with a coating.

49. Poor adhesion Adhesion to steel Adhesion to previous coats of paint
Proper surface preparation
Quality primer
Use polymers with strong and concentrated Lewis basicity. Tightly adhering rust on steel surface enhances adhesion
To metallic iron, use covalently reacted polymers such as silanes and siloxanes
Adhesion to previous coats of paint
Properly matched coating system
Match Lewis acidity/basicity of the coatings
Beware of low molecular species in the coating that will migrate to the surface
Proper Recoat times

50. Chemical attack
Proper coating selection for the exposure environment

51. Prevent Coating Failures
Corrosion Protection
Good Design
Good Paint
Good Specifications
Good Contractors
Good Inspection
Good Maintenance

52. GOOD SPECIFICATIONS Must Be Understandable Must Be Enforceable
If not, Inspectors then rely on “Painting Common Sense”
Requires Education
Must Be Enforceable
At all levels
By the Courts

53. SPECIFICATION TYPE - DESIGN
A Formula/Design specification provides in-depth detail about the functional and non-functional design requirements. It provides the user with all of the information and references necessary so they can achieve the intended outcome. The design specification result should be consistently reproducible providing the same standard outcome.
Provides specific instructions.

54. SPECIFICATION TYPE - PERFORMANCE
Permits greater contractor flexibility to develop innovative solutions and build in quality through process control and continuous process improvement
Enhances competition and much needed force modernization
Means & methods are up to the Contractor

55. SPECIFICATION LANGUAGE
SHALL: A requirement
SHOULD: A preference or strong recommendation
MAY: Acceptable alternatives

56. SPECIFICATION FORMATS
CSI (Construction Specifications Institute)
Part 1 – General
Part 2 – Products
Part 3 - Execution

57. PART 1 – GENERAL (SPECIFICATIONS)
1.7 Project/Site Conditions
1.8 Sequencing and Scheduling
1.9 Safety and Environmental Compliance
1.10 Warranty
1.11 Maintenance (optional)
1.1 Scope
1.2 References
1.3 Definitions
1.4 Submittals
1.5 Quality Assurance
1.6 Delivery, Storage,
and Handling

58. STANDARDS & REFERENCES
A standard is a general document that does not change from job-to-job.
Typically included within specifications, thus becoming a binding part of the contract.
Inspectors must be familiar with all reference standards.

59. STANDARDS & REFERENCES
ACI – American Concrete Institute
AISI – American Iron & Steel Institute
ANSI – American National Standards Institute, Inc.
API – American Petroleum Institute
ICRI – International Concrete Repair Institute.
ASTM – American Society for Testing and Materials
AWWA – American Water Works Association
NACE – National Association of Corrosion Engineers
SSPC – Society of Protective Coatings

60. PART 2 - PRODUCTS 2.1 Manufacturers 2.2 Materials 2.3 Equipment
2.4 Source Quality Control

61. PART 3 - EXECUTION 3.1 Examination 3.2 General Preparation
3.3 Surface Preparation
3.4 Application
3.5 Quality Control
3.6 Site Clean-up

62. 3.3 SURFACE PREPARATION
The majority of premature coating failures can be tied to surface preparation
Reference appropriate surface preparation standards

63. PREPARATION STANDARDS
SSPC-SP1
SSPC-SP2
SSPC-SP3
SSPC-SP5/NACE 1
SSPC-SP6/NACE 3
SSPC-SP7/NACE 4
SSPC-SP10/NACE 2
SSPC-SP11
SSPC-SP12/NACE 5
SSPC-SP13/NACE 6
SSPC-SP14/NACE 8
SSPC-SP15/NACE 6

64. 3.5 QUALITY CONTROL (Hold-Point)
Defines the minimum testing required by the contractor and/or the inspector.
Determines who provides inspection equipment.
Provides for dispute resolution between multiple parties
Describes documentation requirements.

65. Prevent Coating Failures
Corrosion Protection
Good Design
Good Paint
Good Specifications
Good Contractors
Good Inspection
Good Maintenance

66. OR GOOD APPLICATORS (TRAINED)
GOOD CONTRACTORS
OR GOOD APPLICATORS (TRAINED)
Past experience
Currently
Can they get bonded?
Changes (pre-qualified)
New improved specifications
Pre-bid meeting
Disbarment investigations
Probably higher prices

67. QUALIFICATIONS Pre-Qualified by Owner
Pre-Qualified by Others (SSPC – PCCP)
SSPC QP 1
SSPC QP 2
SSPC QP 3

68. SSPC QP 1 The program’s objective is to determine if an
industrial/marine coatings Contractor has the personnel, organization, qualifications, procedures, knowledge, and capability to produce quality surface preparation and coating application of complex industrial and marine structures.

69. SSPC QP 2
Assess the primary capabilities of contractors to protect worker health and safety and the environment, while successfully completing industrial/marine hazardous paint removal projects.

70. SSPC QP 3 Verify the capabilities of shop facilities
to perform quality surface preparation and coating application. SSPC achieves this by independently auditing shops to determine whether they have the personnel, organization, quality procedures, knowledge, and capability to produce quality surface preparation and protective coating application in a shop environment.

71. Prevent Coating Failures
Corrosion Protection
Good Design
Good Paint
Good Specifications
Good Contractors
Good Inspection
Good Maintenance

72. INSPECTION CONSISTS OF
Witness
Verify
Measure
Document

73. THE QC INSPECTOR
The role of the Inspector is to assure that all the requirements of the Specification are accomplished and documented, to report any deviation, and assure that they are corrected.

74. THE QC INSPECTOR Must have the authority to make decisions.
Must have the freedom to identify problems.
Should report directly to management.

75. HOLD-POINT INSPECTIONS
During surface preparation
During mixing and thinning operations
During coating application

76. DURING SURFACE PREPARATION
See that surface is cleaned as specified.

77. DURING MIXING & THINNING
Coating is mixed thoroughly and in the proper proportions.
Correct amount of thinner is used.
Correct type of thinner is used.
Temperatures and pot-life observed.

78. DURING COATING APPLICATION
Correct coating thickness is attained.
Specified recoat window is observed.
Specified surface temperature is observed.
Specified coating is applied.

79. COMMUNICATION
Avoids
Confusion
Delays
Misunderstandings
Conflicts

80. DOCUMENTATION Daily Inspection Reports (DIR’s) Meetings Communication
Hold-Point inspections

81. DAILY INSPECTION REPORTS (DIR’S)
Site & Environmental Conditions
Surface Preparation
Coatings (Materials)
Application
Dry Film Thickness
Crew & Equipment
Non-Compliance
“Hold-Points”

82. Prevent Coating Failures
Corrosion Protection
Good Design
Good Paint
Good Specifications
Good Contractors
Good Inspection
Good Maintenance

83. MAINTENANCE PAINTING Typical Rehabilitative Options Do Nothing
Spot Repair
Zone Repair
Spot/Zone + Overcoat
Full Removal & Replacement
In most company’s budgets, maintenance is typically one of the first items that is reduced if not eliminated completely when monies become tight. Whether the initial painting costs were only a few thousand dollars or as much as a few millions, getting the most out of those dollars is critical since future budgets to maintain the assets are often unknown; too slow to react in a timely manner; and or just eliminated. The technology being built into coating technology is generating systems that can last up and extending beyond 20 years with little to minimal attention/repair.

84. REVIEW
A successful coating project requires a complete and thorough understanding of:
Corrosion
Coatings (chemistry)
Industry Standards
Surface Preparation
Application
Inspection (Hold-Points, Equipment & Communication)
Maintenance

85. QUESTIONS
Thank you