Single Coat

1
Single Coat Rapid Cure Tank Coating Systems

• Improved Tank Preservation Processes
• April 2004

2
Program Team

• Program Sponsor
• Office of Naval Research
• Transition Sponsor/Materials Technical Authority
• Naval Sea Systems Command 05M
• Fleet Demonstration Partners
• COMNAVSURFLANT, COMNAVSURPAC
• COMNAVAIRLANT, COMNAVAIRPAC
• Technical Development and Implementation Labs
• Naval Research Laboratory, Code 6130
• Naval Surface Warfare Center, Carderock Division,
  Code 613

Naval Research Laboratory Arthur A. Webb (202)
404-2888, awebb_at_ccs.nrl.navy.mil Paul
Slebodnick 202-404-7298, Slebodnick_at_nrl.navy.mil
Bill Groeninger 757-652-4838,
Groeninger_at_ccs.nrl.navy.mil
Naval Surface Warfare Center Bill
Needham 301-227-5034, NeedhamWD_at_nswccd.navy.mil R
ich Hays 301-227-5135, (HaysRA_at_nswccd.navy.mil
3
Program Objectives

• Develop Single Coat and Rapid Curing Coating
  Systems to Reduce Labor and Time Associated with
  Tank Preservation
• Replace Current 3 Coat System
• Coating Systems with Edge Retention
• Environmental Compliance
• High film build in single application
• Tanks can be returned to service quickly
• Assess performance of coating systems
• Industrial application
• Actual service conditions
• Determine application limitations
• Representative service
• Range of complexities
• Multi platform applications- Amphibious, Carrier,
  Combatant Ships
• Low complexity for initial installations
• Increasing complexity as application experience
  increases and producibility issues are addressed
• Tanks scheduled for preservation
• Select tanks in work package designated for
  represervation
• Program provides funding for coating application,
  coating, tech assistance, and QA
• Cost Sharing with Fleet funding for surface
  preparation

4
Background

• Definitions
• Single Coat
• A single application product with shorter
  production cycles
• Currently employing solvent-free polyurethanes
• Rapid Cure
• A multiple application product with shorter cure
  and overcoat characteristics resulting in reduced
  production cycles
• Currently employing solvent-free epoxy coatings

5
Cure Speed Classification
General classification of coatings based on cure
times
Typical cure times at various temperatures for
coating types
6
Single Coat Application

• Not a single pass application
• Process is the application of a polyurethane
  system
• One complete coating system during work shift
• Operation consists of three distinct coating
  applications each within perspective overcoat
  window for product
• Work progresses in sections within tank
• When section completed, application moves to next
  section
• Allows for real-time (concurrent) QA/QC

7
Legend
Application Sequence
First Pass
Second Pass
Using a Single Coat System
3rd Pass (Completed)
1
2
3
1
2
Sequence Approach 2-10 minutes between sections
Completed
Completed
3
1
2
3
Done!
All inclusive process, no leaving tank between
subsequent coats
8
Current Single Coat Candidates
Polyurethane Systems

• Futura Protec II PW-ER
• MIL-PRF-23236 testing completed, passes all tests
• SW, Fuel, Comp Fuel, CHT, PW
• Futura Futurathane 527
• Initial MIL-PRF-23236 testing underway
• Madison Chemical Industries Corrocote II
• Progressing with 23236 laboratory qualification
• SW, Fuel, Comp Fuel, CHT, PW
• Edge retention of first and second versions
  failed
• 4rd version ER under review
• Product not yet qualified

9
Current Rapid Cure Candidates

• Sherwin-Williams Fast-Clad
• Progressing with 23236 laboratory qualification
• SW, Fuel, Comp Fuel, CHT
• No potable water
• Product not yet qualified
• International Intergard 783
• MIL-PRF-23236 testing initiated Aug 03
• SW, Fuel, Comp Fuel
• Sigma EX 1762
• Initial MIL-PRF-23236 qualification underway
• Formulated for all tank applications, except
  potable water

10
Current Rapid Cure Candidates
Curing Performance for Current Fast Cure
Candidates
ND no difference or change from dry hard reading
coatings were cured through at the dry hard
measurement time
11
Single Coat Demonstrations

• USS GUNSTON HALL (LSD-44) May 2002
• Madison Marithane
• 1 Tank 3-121-1-W
• USS WHIDBEY ISLAND (LSD-41) Aug 2002
• Madison Marithane
• 2 Tanks 3-129-1-W 3-103-1-W
• USS GEORGE WASHINGTON (CVN 73) June 2003
• Madison Marithane
• 1 DC Void 3-123-1-V
• USS TORTUGA (LSD-46) Nov 2003
• Futura Protec II
• 1 Tank 5-140-1-W
• USS ASHLAND (LSD-46) Jan 2004
• Futura Potable Water
• 2-Tanks 6-41-1-W 6-41-3-W
• Successive demonstration of same product
  involves tanks with progressively higher
  complexity and size

12
USS GUNSTON HALL LSD-44, Single Coat
Application Insertable Stalk Inspection Sys
(ISIS) Coatings Assessment Images In-Service
Inspection, 6 months
Corrosion Sensors
13
USS WHIDBEY ISLAND LSD-41, Single Coat
Application Aug 2002 PMA, NORSHIPCO VA Seawater
Ballast Tank 3-129-1-W 3-103-1-W Application of
Madison Marithane II Ultra Polyurethane
14
USS TORTUGA LSD-46, Single Coat
Application Futura Protec II applied in Tank
5-140-1-W , September 2003
15
Rapid Cure Demonstrations

• USS WASP (LHD-1) June 2003
• Sherwin-Williams Fast Clad
• 1 Tank 5-104-1-W
• USS TORTUGA (LSD 46) Nov 2003
• Sherwin-Williams Fast Clad
• 2 Tanks 5-125-1-W, 5-129-1-W
• USS ASHLAND (LSD-46) Jan 2004
• Sherwin-Williams Fast Clad
• 4-Tanks 3-98-1-W, 3-103-2-W, 3-129-2-W,
  5-129-2-W
• Successive demonstration of same product involves
  tanks with progressively higher complexity and
  size

16
USS WASP LHD-1, Rapid Cure Application Sherwin-Wil
liams Fast-Clad applied in Tank 5-140-1-W , 12
June 2003
17
USS TORTUGA LSD-46, Rapid Cure Application Sherwin
-Williams Fast Clad applied in Tank 5-129-1-W ,
September 2003
18
Demonstration Process Requirements

• Surface Preparation
• SSPC SP-10
• Conductivity lt30mS/cm
• Profile 2-4 mils
• Environmental Control
• 50 RH maximum
• Dew point and ambient temperature gt5o difference
• Certified applicator
• Completed training and demonstrated proficiency
  prior to commencement of job
• Coating application
• Holiday inspection on all angles and flange
  backsides
• Development of optical holiday detection
  techniques

19
Lessons Learned

• Single Coat systems exhibit propensity for rapid
  turn-around
• Tank can be completely coated and finished in one
  day
• Applicator training is absolutely essential
• Urethane systems less user friendly
• Requires plural pump and dual feed or impingement
  mix gun
• Coating is susceptible to moisture during
  application
• Rapid cure systems allow for reduced maintenance
  cycle
• Painting cycle time can be significantly reduced
• Applicator training less critical but necessary
  for plural component usage.
• Epoxy-based systems more user friendly
• Uses plural pump with single feed guns
• Less affected by moisture during application

20
Lessons Learned
General Product Selection Guidelines
21
Need for Improvement

• Single coat polyurethanes
• Curing speeds extremely attractive
• Low temperature capabilities also of interest
• Solvent free formulations ideal for shipbuilding
  and repair
• However current polyurethane systems not ideally
  suited for marine and industrial application
  environment
• Poor control of overcoat windows
• Susceptible to application errors
• Can exhibit limited adhesion
• Limited chemical resistance (fuel and alkaline
  conditions)
• Corrosion inhibition properties can unpredictable
• Formulation difficulties
• Limited raw materials base (resins)
• New resin technologies needed
• Need corrosion inhibition, chemical resistance
  and adhesion of amine-cured epoxies with the
  rapid cure properties of a polyurethane

22
New Technology

• NRL Novel Resins
• Functional polyol resins synthesized from current
  widely available raw materials
• Solvent free
• Cured using all commercial isocyanates
• Aromatic for chemical resistance
• Aliphatic for weatherability

23
Background

• Current high solids and solvent free
  polyurethanes
• Polyether polyol blends
• Low viscosity
• Moderate moisture absorption (polyether backbone)
• Low to medium isocyanate demand
• Chemical resistant linings using aromatic
  isocyanates
• Low molecular weight acrylic or polyester polyols
• High viscosity
• Moderate moisture absorption
• Poor alkaline resistance (acrylic side chains
  ester backbone)
• Low isocyanate demand
• Used for weatherable coatings (aliphatic
  isocyanate cured)

24
Novel Resins

• Modified aliphatic backbone
• Alkaline resistance
• Low moisture pick up
• Primary and secondary hydroxyl functionality
• Primary OH for reaction
• Secondary OH for adhesion
• Solvent free
• Low and medium viscosity
• Medium to high isocyanate demand
• Enhanced chemical resistance (aromatic
  isocyanate)

25
Standard Features

• Solvent free
• Requires no solvent during manufacturing
• Rapid cure system
• 30 Minutes _at_ 25C
• Instant cure system
• lt 1 minute _at_ 25 C
• Variable Viscosity
• lt 100 Cps for weatherable systems
• 10,000 Cps for chemical resistant systems
• High adhesive strength
• gt2000 psi

26
Special Features

• Zero VOC
• No solvents employed in manufacturing or
  application
• Variable functionality
• Equivalent weights ranging from 76 to 250
• Gloss retention
• Comparable to acrylic polyurethanes
• Chemical Resistance
• Comparable to current epoxies
• Rapid cure capability
• Controllable via structure and catalyst levels

27
Physical PropertiesComparative Properties of
NRL Resin Systems
28
Physical Properties
Viscosity vs. Temperature for 3 Systems
Constant shear rate of 1333/s
29
Mechanical Properties
Effect of Post-Cure Baking 1 hr _at_ 100C Tensile
Values of NRL Resins Compared to Epoxy
Tensile Strength (psi)
Bis-A Epoxy cured with aliphatic polyamine
30
Adhesion Performance
Comparison of NRL Systems to Commercial Epoxy
31
Chemical Resistance
Methanol and Xylene Resistance Compared to
Commercial Epoxy Systems
32
Weathering Resistance
Systems Cured with Desmodur N3600
Note no light stabilizers added
33
Targeted Uses
Solvent Free Rapid Cure Nonskid
Solvent Free Exterior Topcoat
Casting Resin and Thermal Barriers
Solvent Free Tank Lining
34
Comparative Properties

• NRL System Design Features
• Good color and gloss retention
• Solvent free aliphatic topcoat
• Good hydrocarbon fuel resistance
• Solvent free aromatic system
• Excellent direct to metal adhesion (self priming)
• Good cathodic disbondment resistance
  (hydrolytically stable)

35
Coatings Formulation

• Resin system can be synthesized by any well
  equipped coating/resin manufacturer
• Specialized reactors and handling equipment not
  required
• Compatible with most pigment materials
• Utilizes standard production processes

Accepts most pigment types
High flexibility non-skid
36
Summary

• Points of Contact
• NRL Technology Transfer Office
• Jane Kuhl [phone]
• Center for Corrosion Science and Engineering
• Arthur Webb, Head, Marine Coatings Section
• [phone] awebb_at_ccs.nrl.navy.mil
• Jozef Verborgt, Marine Coatings Section
  Consultant
• [phone] jefverborgt_at_aol.com
• Keith Lucas, Branch Head, Center for Corrosion
  Science and Engineering
• [phone] klucas_at_ccs.nrl.navy.mil