navsea documents - the society for protective … of coatings on u.s. navy submarines. the...

Topics: • NAVSEA documents related to preservation of ships• Exercise in use of these documents

Scope This section gets students acquainted with guidance documents for the preservation of ships.

Learning OutcomeAt the end of this section, students will be able to:

• Identify the major NAVSEA guidance documents concerning the preservation of ships and describe how to use them in their work.

NAVSEA has prepared detailed guidance documents for the different aspects of shipboard corrosion control by coatings. These documents include:

• Naval Ships Technical Manual, Chapter 631, Preservation of Ships in Service

• Naval Ships Technical Manual, Chapter 634, Deck Coverings General• NAVSEA Standard Item 009-32, Cleaning and Painting Requirements• NAVSEA Standard Item 009-04, Quality Management System• NAVSEA Standard Item 009-26, Deck Covering Requirements,

accomplish• NAVSEA Coating Performance Specifications (e.g., MIL-PRF-23236,

MIL-PRF-24647 and MIL-DTL-24441) with supporting Qualified Products Databases and NAVSEA-Reviewed ASTM F718 Data Sheets

4 NAVSEA Documents

• Maintenance Standard Item (MS) 6310-081-015

Section 1 - Introduction Reference Documents General Painting Requirements Coating Selection

Section 2 - Safety General Hazards General Paint/Solvent Information for Fire/Explosion Paint and Solvent Health Hazards Surface Preparation/Paint Removal Methods and Tools

NSTM CHAPTER 631 OVERVIEW

NAVSEA Basic Paint Inspector Training: NAVSEA Documents

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Paint Mixing Paint Application Specific Coating System Concerns

Section 3 - Paint Equipment Paint Thickness Gages Paint and Paint Materials

Section 4 - Reconditioning Flooded and Smoke-Contaminated EquipmentSection 5 - Surface Preparation Surface Cleaning Methods Abrasive Blasting Waterjetting and Water cleaning Underwater Hull Cleaning Solvent Cleaning Acid Cleaning Paint Removers Steam Cleaning Pickling Alkaline Cleaning Hand Cleaning of Ship’s Bilges Preparation Quality Assurance Tests, Inspections and Records

Section 6 - Paint Application Guidance and Requirements Painting Records, Reports and Documents Basic Preparations Basic Painting Procedures Paint Failures

Section 7 - Paint Application Procedures Epoxy Polyamide Coatings (MIL-DTL-24441) MIL-PRF-23236 Coatings Pretreatment Wash Primer Vinyl Plastisol Coatings Thermal Spray Coatings Erosion-Resistant Epoxy Coatings Antisweat Treatment and Compound Powder Coatings TT-P-28 Heat-Resistant Coatings Water-based Coatings MIL-PRF-24596 Epoxy Repair and Hull Smoothing Compounds

Section 8 - Shipboard Paint Application General Requirements and Guidance for Metal Surfaces General Requirements and Guidance for Non-Metallic Surfaces Surface Ships and Craft Underwater Hull Coatings Potable Water Tank Coating Systems Feed Water and Fresh Water Drain Collection Tank Coating Systems

NSTM CHAPTER 631 OVERVIEW (continued)

Navy Basic Paint Inspector Training: NAVSEA Documents

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Machinery and Piping Electrical and Electronic Equipment Motor and Generators Electric Cables and Supports Metal Enclosures Interior Communication and Fire Control Equipment Lighting Systems Exterior Radar, Fire Control, Antennas and Electronic Equipment Sonar Domes Miscellaneous Equipment Shipboard Hems not to be Painted Surface Ships Hospital Ships Submarines

Section 9 - Boats and Small Craft Above-Water Surfaces Underwater Surfaces Miscellaneous Equipment Open Boats Cabin Boats Boats for Hospital Ships Identification Markings Plastic Boats

Section 10 - Naval Ship’s Markings and Awards Ship Names Ship Nameboard Draft Marks Distinguishing Numerals and Letters Letter Awards Ship and Small Craft Insignias Hospital Ships

Section 11 - Quality Assurance for Critical Coated Areas Defined Critical Coated Areas Required for Critical Coated Areas Test and Inspection Records Shipyard Blaster and Painter Certification Coating Inspector Certification Coating Inspector Responsibilities Inspection of Storage and Receipt Inspection Facilities In-process Inspections Audits of Facility and In-process Inspections Inspection of Final Coating Systems Review of Records for Final Coating Evaluation Acceptance/Rejection of Final Coating Systems



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NAVSEA COATING PERFORMANCE SPECIFICATIONS AND SUPPORTING DOCUMENTS

NAVSEA STANDARD ITEM 009-32 OVERVIEW

NAVSEA STANDARD ITEM 009-04 OVERVIEW

NAVSEA Standard item 009-04 provides quality management requirements for Navy products, including cleaning and painting work. It describes requirements to establish, document, implement, and maintain a Quality Management System as a means of ensuring the product conforms to specified requirements. These include:

• Corrective and preventive action programs• A test and inspection plan• Documentation procedures

NAVSEA Standard Item 009-32 provides cleaning and painting requirements for Navy ships. This information covers the following general subjects:

• Definitions of critical coated areas and technical terms used• Blast cleaning, including profile and cleanliness• Application, including striping and special (e.g., topcoating) application

concerns • Use of specialized coatings, including nonskid, antifouling, fire-

retardant, and powder coatings• Quality assurance requirements, including inspection forms for

documentation• Eight tables of approved surface preparation and coating systems for

different surface areas.• QA inspection forms

NAVSEA has the responsibility for many military performance specifications related to coatings for ships. Three of the more important of these are MIL-PRF-24647, MIL-PRF-23236 and MIL-DTL-24441. MIL-PRF-23236 and MIL-DTL-24441 are applicable to tanks, including potable water tanks and other ship structures, interior, or exterior for corrosion control. MIL-PRF-24647 is applicable to paint systems, anticorrosive and antifouling, for ship hulls.

Section 12 - Preservation Process Instructions Approved Preservation Process Instructions Preservation Process Instruction Availability Technical Conflicts Quality Assurance Forms

Note: This document is not available to the public. You must get proper permission to obtain.



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Associated with these documents are Qualified Products Databases (QPDs) and NAVSEA-reviewed ASTM F718 Data Sheets and any NAVSEA periodic Advanced Coating, Covering and Cleaning Systems messages. The QPDs list the commercial products approved under the requirements of the particular performance specification for use by or for the government in the acquisition of these products. The NAVSEA-reviewed ASTM F718 Data Sheets are short (about two pages) summaries prepared by the manufacturer of each approved product to provide identification and use of the product:

1. Generic type and description 2. Manufacturers data 3. Properties 4. Surface preparation minimum requirements 5. Mixing procedure 6. Application

There is a special highlighted section for Special Safety Precautions.

Other Qualified Products and Government specifications can be found at http://assist.daps.dla.mil/online/start/.

This submarine maintenance standard (SMS) is the governing techni-cal document for submarine preservation and maintainence. It consolidates requirements into a single standard dedicated to the proper application and maintenance of coatings on U.S. Navy submarines. The requirements it contains provide guidance for Intermediate Maintenance Activities (IMAs), Naval ship-yards, and contractors.

This standard does not supersede NSTM 631. However, in instances where requirements specified are conflicting, the SMS governs. This also applies to DDGOS, MRCs, MSs, and individual ships’ Paint Schedule requirements.

MS 6310-081-015 shall be referred to for all application and QA/QC requirements and all information for submarine preservation shall be verified per application documents prior to any work being performed.

SUBMARINE MAINTENANCE STANDARD (MS) 6310-081-015 SUBMARINE PRESERVATION


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The following questions are intended to familiarize you with the NAVSEA documents described in this section. The questions should be divided so that each team has a question from each document. Questions 1 through 7 can be answered using information found in NAVSEA Standard Item 009-32. Questions 8 through 11 can be answered using information in NAVSEA Standard Item 009-04.

1. Which type and class of MIL-PRF-23236 products are exempt from dew point and relative humidity requirements?

2. What type of fire-retardant paints should be used in preference to chlorinated alkyd fire retardant paints?

3. What is the definition of a tack coat?

4. How many profile readings shall be taken in the first 1,000 square feet of a blast cleaned steel surface?

5. Upon completion of surface preparation are pH measurements required? If you answered yes, what is the acceptable pH range?

NAVSEA STANDARD ITEM 009-32 AND NAVSEA STANDARD ITEM 009-04 TEAM EXERCISE


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6. Where would you find information about surface preparation for aluminum surfaces? What is recommended for spot cleaning?

7. Where can you find information regarding powder coatings? Where are powder coatings used?

8. When is the use of black-oxide coated brass threaded fasteners (BOCBTF) authorized under contract work?

9. When must an initial copy of the Test and Inspection Plan be submitted to the Supervisor?

10. At what times shall the Test and Inspection Plan be revised and updated?

11. When must Test and Inspection records be documented?

NAVSEA STANDARD ITEM 009-32 AND NAVSEA STANDARD ITEM 009-04 TEAM EXERCISE (continued)


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Complete the team exercise making use of the following documents:

• NAVSEA Standard Item 009-32• MIL-PRF-24647• NAVSEA-Reviewed ASTM F718 Datasheets• QPD-24647

A DDG-47 Class Navy Ship has entered a scheduled dry-dock availability. The contract calls for complete removal of the existing underwater hull coating system, followed by application of an approved copper-ablative antifouling (AF) system. A 12-year service life is required.

Your team is to choose a specific coating system and oversee the QA for this job. To that end, your team needs to answer the following questions:

1. What document specifies the required surface preparation and coating specification for the underwater hull?

2. What performance specification is required for the 12-year ablative underwater hull system? Where specifically is the requirement found?

3. What level of surface preparation is required, prior to the application of the new AF system? Where is this specified?

4. The following additional information is known:

• The temperature is expected to be around 38°F during the application.• Environmental regulations require that the volatile organic content

(VOC) of the AF topcoats shall not exceed 400 g/L, and that the VOC of any other individual paint in the system shall not exceed 340 g/L.

Using MIL-PRF-24647, classify the required coating system as to Type, Class, Grade, and Application. Explain your choice.

DOCUMENTATION TEAM EXERCISE


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5. Using the qualified products database, QPD-24647, and the classification required in question 4, pick a manufacturer and coating system to meet the requirements of this job.

6. After you have made your selection, one of the shipyard painters mentions that there is a sufficient quantity of an International AF system in stock. This system consists of Intergard 264 (anticorrosive coating) and Interspeed 640 (AF coating). On checking QPD-24647, you determine this system is classified as Type II, Class 1, Grade A, Application 3. Is this system suitable for your application? Why or why not?

7. What certifications are required for the following personnel? Why?

• Abrasive blasters? • Coating Inspectors? • Contractor(s) performing the blasting and painting operations?

SUMMARY

This chapter has discussed and described those NAVSEA guidance documents for the preservation of ships and described how to use them. The different documents relate to different aspects of shipboard corrosion control by coatings.

NAVSEA Standard Item 009-32 is periodically updated. Below is a list of recent revisions.

• Prohibits the use of steel shot on LHA, LHD, LPD and LSD nonskid flight decks.

• Allows the retention of preconstruction primers in all areas except: potable water, reserve feedwater and freshwater drain collecting tanks; nonskid applications and single-coat applications.

• States that tank, void and vent plenum bolting rings require SSPC-SP 15 surface preparation and one coat of MIL-PRF-23236 primer or two coats of MIL-DTL-24441.


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• Added the following areas as critically coated areas;

o Recovery, Assist, Securing and Traversing (RAST) track trough (including sumps)

o Aircraft Launch and Recovery Equipment (ALRE) System defined herein as catapult wing voids, catapult troughs, catapult exhaust blowdown trunks, barricade stanchions and wells, catapult jet blast deflector pits, and associated void spaces

o Arresting gear sheave foundations

o Valve Regulated Lead Acid (VRLA) Battery Compartment at conversion

• Provides requirements for what receipt inspections testing is required by conformance testing and/or receipt inspection.

• It is now a NAVSEA Standard Item 009-32 requirement that potable water tanks are coated with white or off-white colors.

• States that for nonskid areas that abrasive blast equipment or waterjet equipment cannot access, substrate shall be prepared to SSPC-SP 11, except that minimum profile shall be 2 mils where accessible. Underside of tie-down bars shall be prepared to SSPC-SP 2 or SSPC-SP 3, however feathering requirements are waived, while remainder of tie-down shall be prepared to SSPC-SP 15.


NAVSEA Documents (4)

NAVSEA Basic Paint Inspector Training!

Topics

l NAVSEA documents related to preservation of ships

l Practical exercise on use of these documents

Scope

l Gets students acquainted with guidance documents for the preservation of ships

Learning Outcome

l Students will be able to identify the major NAVSEA guidance documents concerning the preservation of ships and describe how to use them in their work

NAVSEA Documents Concerned with Ship Coatings

l NSTM Chapter 631 l NSTM Chapter 634 l NAVSEA Standard Item 009-32 l NAVSEA Standard Item 009-04 l NAVSEA Standard Item 009-26 l NAVSEA Coating Performance

Specifications and their QPDs and NAVSEA-Reviewed ASTM F718 Data Sheets

Relevant Documents

l NSTM Chapter 631 and 634 – Ships’ Force – Used when NAVSEA Standard Item 009-32 is silent on

an issue or references NSTM Chapter 631 and 634 l NAVSEA Standard Item 009-32

– Government shipyards, contractor shipyards, and regional maintenance centers (RMCs)

l SUBMEPP Preservation Standard – Submarine community

l Ship Specifications – New construction


NSTM Chapter 631 NSTM Chapter 631

–  Section 1 – Introduction –  Section 2 – Safety –  Section 3 – Paint Equipment –  Section 4 – Reconditioning of

Flooded and Smoke-Contaminated Equipment

–  Section 5 – Surface Preparation –  Section 6 – Paint Application

Guidance and Requirements –  Section 7 – Paint Application

Procedures

–  Section 8 – Shipboard Paint Application

–  Section 9 – Boats and Small Craft

–  Section 10 – Naval Ships’ Marking and Awards

–  Section 11 – Quality Assurance for Critical Coated Areas

–  Section 12 – Preservation Process Instructions

NSTM Chapter 631

l  NSTM Chapter 631 is a controlled document. See your government representative for more information and to obtain a copy.

NAVSEA Standard Item 009-32

l  Summary of coating requirements can be found in: –  Table 1, Surface Ship Underwater Hull Areas –  Table 2, Surface Ship Exterior Areas –  Table 3, Surface Ship Interior Spaces –  Table 4, Surface Ship Tanks and Voids –  Table 5, Surface Ship Misc. Areas –  Table 6, Submarine Exterior Hull Areas –  Table 7, Submarine Interior Areas –  Table 8, Submarine Tanks and Voids


l  Defined critical coated areas and definitions of technical terms

l  Blast cleaning, including profile l  General and special applications l  Use of specialized coatings l  Eight tables of systems for different areas l  QA Inspection forms

NAVSEA Standard Item 009-32 (cont’d.)

l  Used by both contractors and the Government l  Applies to all vessels (surface ships, carriers, and

submarines) l  NAVSEA Standard Item 009-32 contains new tables

and notes pertaining to submarines l  QA forms found at www.nstcenter.biz. The forms are

still part of NAVSEA Standard Item 009-32, but are no longer physically included in the document –  Note: Make sure you are using correct QA forms from

NAVSEA Standard Item 009-32, as there is one form for shipyards/government and one for contractors



l Corrective and preventive action programs (CA/PA)

l A test and inspection plan l Documentation procedures

NAVSEA Coating Performance Specifications

l NAVSEA is responsible for many performance specifications for coatings for ships (e.g., MIL-PRF-23236 and MIL-DTL-24441 for tanks. MIL-PRF-24647 for anti-corrosive and antifouling systems)

l These specifications usually have QPDs and NAVSEA-Reviewed ASTM F718 Data Sheets

NAVSEA-Reviewed ASTM F718 Data Sheets

l Generic type and description l Manufacturer’s data l Properties l Surface preparation minimum requirements l Mixing procedures l Application l WFT and DFT limits

MS 6310-081-015

l Technical document for submarine preservation and maintenance, aligned with the requirements of NAVSEA Standard Item 009-32.

l Provides requirements for proper application and maintenance of coatings on U.S. Navy submarines for Intermediate Maintenance Activities (IMAS), Naval Shipyards, and Contractors

Team Exercises

l Complete the following two exercises using the appropriate NAVSEA documents.

Summary

l This chapter has discussed and described those NAVSEA guidance documents for the preservation of ships and described how to use them. The different documents relate to different aspects of shipboard corrosion control by coatings


Summary (cont’d.)

l NAVSEA Standard Item 009-32 is revised periodically. Recent changes include: – Prohibits the use of steel shot on LHA, LHD, LPD and

LSD nonskid flight decks. – Allows the retention of preconstruction primers in all

areas except: potable water, reserve feedwater and freshwater drain collecting tanks; nonskid applications and single-coat applications.

Summary (cont’d.)

– States that tank, void, and vent plenum bolting rings require SSPC-SP 15 surface preparation and one coat of MIL-PRF-23236 primer or two coats of MIL-DTL-24441.

Summary (cont’d.)

– Added these critically coated areas: •  Recovery, Assist, Securing and Traversing (RAST)

track trough (including sumps)

•  Arresting gear sheave foundations

Summary (cont’d.)

•  Aircraft Launch and Recovery Equipment (ALRE) System defined herein as catapult wing voids, catapult troughs, catapult exhaust blowdown trunks, barricade stanchions and wells, catapult jet blast deflector pits, and associated void spaces

•  Valve Regulated Lead Acid (VRLA) Battery Compartment at conversion

Summary (cont’d.)

– Provides requirements for what receipt inspections testing is required by conformance testing and/or receipt inspection.

– Requires that potable water tanks are coated with white or off-white colors.

Summary (cont’d.)

– States that for nonskid areas that abrasive blast equipment or waterjet equipment cannot access, substrate shall be prepared to SSPC-SP 11, except that minimum profile shall be 2 mils where accessible. Underside of tie-down bars shall be prepared to SSPC-SP 2 or SSPC-SP 3, however feathering requirements are waived, while remainder of tie-down shall be prepared to SSPC-SP 15.

Topics• Solvent cleaning• Chemical cleaning• Steam cleaning• Detergent/water cleaning

Scope This section gets students acquainted with the use of liquid products used in cleaning surfaces of ships prior to coating.

Learning Outcome At the end of this section, students will be able to describe these cleaning methods and identify their typical uses, advantages, and limitations.

This section discusses the use of liquid cleaning materials, including steam, on metal surfaces abroad ships that act by chemical or detergent action rather than physical contact. Mechanical (hand and power tool) and abrasive blast cleaning methods will be discussed in subsequent sections.

Unfortunately, many of the solvents routinely used for cleaning are no longer available. Many of these solvents have been prohibited because they are considered ozone depleting substances (ODS) or hazardous air pollutants (HAPS). The overviews given below should guide you in selecting a method which is applicable to the surface preparation job at hand.

Solvent Cleaning (SSPC-SP 1) Solvents are liquids in which another substance can be dissolved. Solvent cleaning prepares the substrate surface by removing oil, grease, dirt, chemical paint stripper residues, moisture, and other foreign matter prior to mechanical cleaning or painting. This is the preferred method for removing oil and grease.

Solvents clean by dissolving and diluting contamination to permit contaminants to be wiped or washed off the surface with more solvent. Solvents include organic solvents (alcohol, paint thinner, etc.), steam, detergents, and water.

Non-Mechanical (Chemical or Detergent) Cleaning Methods

5

NSTM CHAPTER 631, SECTION 5

NAVSEA Basic Paint Inspector Training: Non-Mechanical Cleaning Methods

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According to NSTM Chapter 631, organic solvents shall not be used for cleaning if their flash points are below 95°F (35°C). Additional safety precautions can be found in NSTM Chapter 631, Section 2.

SSPC-SP 1 also covers solvent cleaning (see Appendix F). This specification is invoked as a requirement of other SSPC cleaning standards such as SSPC-SP 10.

Procedure for Solvent Cleaning:1. First remove bulk surface contaminants with appropriate method (e.g. use

a wire brush to remove soil and loose rust).2. The surface is then scrubbed with brushes or rags saturated with solvent.

Do not dip rags into the solvent—pour the solvent onto the rag—this prevents contamination of the entire container of solvent.

3. Use clean rags and fresh solvent to rinse and wipe the surface dry.

Immersing the work in the solvent, and spraying of solvent, are alternative methods for solvent cleaning.

Typical Solvents Used: mineral spirits, super high flash naphtha, butanol (n-butyl alcohol), PF-145HP. Solvents being phased out: 1,1,1-trichloroethane, Freon (for environmental reasons).

Note: For areas prepared to SSPC-SP WJ-2/NACE WJ-2, Very Thorough Cleaning with vacuum self-contained ultra high pressure waterjetting equipment, the requirement of initial degreasing is waived. In areas that require 100% preservation of major structural repairs, modifications may be accomplished without requirements of NAVSEA Standard Item 009-32 until the full surface preparation can be accomplished in accordance with applicable table and line.

Acid Cleaning Acid cleaning is a method used to clean iron and steel by treating the surface with a mild acid solution. It cannot be used on aluminum, magnesium, or stainless steel surfaces.

Acid cleaning removes surface contaminants by treating the surface with a phosphoric acid solution containing small amounts of solvent, detergent and a wetting agent. This method is not suitable for removing oil or grease from the surface, but it will remove mill scale, light rust, rust scales and will also slightly etch the substrate surface for better coating adhesion.

Four Methods of Acid Cleaning:1. WASH OFF

• Application of the acid cleaner• Allow time for cleaner to act• Thorough rinsing• Drying period before painting

Navy Basic Paint Inspector Training: Non-Mechanical Cleaning Methods

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2. WIPE OFF• Application of the acid cleaner• Allow time for the cleaner to act• Wipe the surface with clean damp cloths• Final wiping with clean dry cloths• Drying period before painting

3. HOT DIP• Immersion of the work piece in hot acid cleaner• Rinse in hot or cold water• Second rinse in weak (5%) acid solution• Drying period before painting

4. SPRAY• Same steps as wash off method but requires pressurized spray

equipment.

Steam Cleaning Steam cleaning is commonly used to remove heavy dirt deposits, soot, and grime. It can cause water based paints to swell and loosen. Additionally, it can be used to remove the thin film formed by corrosion preventive compound, MIL-PRF-16173, Grade 1.

Typically, hot water or steam with pressures of between 90 and 100 psi are used. Steam cleaning can also be used in conjunction with naphtha-resin soap solutions and paint removers. Wire brushing or brush off blasting may be necessary to complete the residue removal.

Pickling Pickling (SSPC-SP 8) is a method used in the shop to completely remove mill scale, rust and rust scale by using sulfuric, hydrochloric, nitric, and phos-phoric acids individually or in combination. Sulfuric acid is most frequently used.

Pickling does not remove oil or grease. Objects to be pickled must be prewashed to remove materials which would prevent the acid from contacting the surface of the substrate.

Pickling cannot be used on aluminum, magnesium or stainless steel substrates. Objects which can be pickled are also limited to the size of the pickling bath. Pickling is the principal method by which objects to be galvanized by the hot dip galvanizing process are pre-treated.

The roughness of the steel surface coming from a pickling bath is considerably less than that of one which has been freshly mechanically blasted, which means it is possible to obtain lower coating adhesion.

Contaminants can collect on the surface of the treatment vats and can contaminate the substrate. If coating adhesion is critical and exposure is severe,


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acid pickling would not normally be preferred.

Alkaline Cleaning Alkaline cleaning is a chemical process that requires careful controls. The most common cleaners are trisodium phosphate, caustic soda (sodium hydroxide), and silicated alkalis. These cleaners are dissolved in fresh water and are used at relatively high temperature, 150°F (66°C), because cleaning efficiency increases with temperature.

Alkaline cleaners cannot be used on aluminum, magnesium, stainless steel or galvanized steel.

Alkaline cleaners attack oil and grease, converting them into soapy residues that can be washed away with water. Alkaline cleaners are also effective in removing some types of old paints by softening or lifting them from the substrate.

These cleaners can be applied by brushing, scrubbing, spraying or by immersion of the surface in soak tanks. Thorough rinsing with fresh water is needed after treatment to remove soapy residues or alkali which will impede paint adhesion and/or cause harmful reactions.

Bilge cleaning requires a significant amount of equipment and controls. According to NSTM Chapter 631, Section 5, if the alkaline cleaning is to be done by the ship’s force, it shall be done only under the technical supervision of qualified and experienced shipyard or industry representatives.

Detergent and Water Detergent cleaning removes oil and grease based contaminants from the substrate. They allow the oil or grease contaminants to be emulsified in the water solution and washed away. Detergents are long organic molecules which have a “fatty” end on one side that is soluble in grease and oil and on the other side a “polar” end which is soluble in water. This method of cleaning is suitable in areas where local regulations or conditions prevent the use of solvents.

A recommended detergent is MIL-D-16791, Type 1, Liquid Detergent. Several non-specification commercial products have also been used successfully.

Procedure1. Mix detergent in water according to package instructions.2. Wash substrate surface.3. Rinse with fresh water.4. Dry surface with air or clean dry rags to remove residual water which

could cause flash rusting. If using compressed air, make sure air source is free of entrained oil or moisture.

Navy Basic Paint Inspector Training: Non-Mechanical Cleaning Methods

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Method Substrate Types Typical Uses Advantages (+) and Limitations (-)

Solvent Cleaning All metals Oily/greasy parts or -Air pollution regulations631, Section 5 or surfaces -HAZMAT storage, disposalSSPC-SP 1 Damp surfaces -Flash points/fire hazards Initial wipe down -Health hazard Final wipe down -Effects on non-metals +Penetrates small crevices +Simple

Acid Cleaning Iron and steel only Cleaning of small parts -Cannot be used on aluminum631, Section 5 Rust removal -Multi-step process -Environmental precautions +Surface etching promotes adhesion +Penetrates crevices and pits

Steam Cleaning Iron alloys Tanks and voids -Limited shipboard use631, Section 5 Steel alloys Some piping systems +Can soften/loosen old paint Copper alloys Removing preservatives +Residual salt removed +No chemicals involved +Penetrates pits +Quick removal of deposits on large areas

Pickling Iron alloys Shop use for mill scale -Shipyard/industrial use only631, Section 5 Steel alloys removal on large steel -Environmental and health precautionsSSPC-SP 8 plate shapes -Not effective for oil and grease -Cannot use on aluminum or stainless steel +Complete mill scale and rust removal

Alkaline Cleaning Iron and steel Bilge cleaning -Handling and disposal of solution631, Section 5 Tank cleaning -Complicated procedure -Cannot use in submarine bilges -Cannot use on aluminum or stainless steel +More efficient, less costly than solvents +Can remove some types of paint +Penetrates pits

Detergent Cleaning Any metal Light soil and oil -Oily water separators not effective Most non-metals removal -Not effective for heavy oil or grease +Most environmentally friendly +Simple

Table 5-1: Summary of Non-Mechanical Cleaning Methods


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SUMMARY

Solvent, chemical, steam, and detergent/water cleaning are defined as a means of cleaning ship surfaces prior to coating. The methods are described according to NSTM Chapter 631, Section 5.

NAVSEA Basic Paint Inspector Training: Non-Mechanical (Chemical or Detergent) Cleaning Methods

Non-Mechanical (Chemical or Detergent) Cleaning Methods (5)


Topics

l Solvent cleaning l Chemical cleaning l Steam cleaning l Detergent/water cleaning

Scope

l Get students acquainted with the use of liquid products used in cleaning surfaces of ships prior to coating

Learning Outcome

l Students will be able to describe these cleaning methods and identify their typical uses, advantages, and limitations

Solvent Cleaning

l  SSPC-SP1 l  Substrate Types

–  All metals l  Typical Uses

–  Oily or greasy parts or surfaces

–  Initial wipe down –  Final wipe down

l  Advantages –  Penetrates small crevices –  Simple to accomplish

l  Disadvantages –  Air pollution regulations –  HAZMAT storage, disposal –  Health hazard –  Effects on non-metals

Note: SSPC cleaning standards, such as SSPC-SP 3, SP 10, and SP 11 require SSPC-SP 1 prior to cleaning. For areas prepared to SSPC-SP WJ/NACE WJ-2, Very Thorough Cleaning with vacuum self-contained ultra high pressure waterjetting equipment, the requirement of initial degreasing is waived.

Ultraviolet Light Test

l  UV light can be used after solvent and other cleaning methods to verify oil & grease removal

l  When hydrocarbons are present, the hydrocarbons will fluoresce as bright green, lime green, or blue/violet on the surface

l  A “water break” test (ASTM F22) is sometimes specified for this purpose.


Ultraviolet Light Test

l  Inspect surface using a UV light to detect hydrocarbons on the surface. The UV light will not allow the proper detection of hydrocarbons on the surface if the surface being inspected is exposed to day or artificial light. For proper UV light hydrocarbon detection, lights must be off for interior spaces, and the inspection must be conducted during darkness for surfaces exposed to sunlight. –  Note from MS 6310-081-015: CAUTION: Black lights

containing mercury must not be brought on board submarines. Mercury-free black lights using light emitting diodes (LEDs) are commercially available.

ASTM F22 Water Break Test

l  Covers the detection of the presence of hydrophobic (non-wetting) films on surfaces and the presence of hydrophobic organic materials in processing environments. When properly conducted, the test will enable detection of molecular layers of hydrophobic organic contaminants. On very rough or porous surfaces, the sensitivity of the test may be significantly decreased.

l  This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

Acid Cleaning

l  Substrate Types –  Iron and Steel Only

l  Typical Uses –  Cleaning of small parts –  Rust removal –  Removes mill scale and rust

l  Advantages –  Surface etching promotes

adhesion –  Penetrates crevices and pits

l  Disadvantages –  Cannot use on aluminum –  Multi-step process –  Environmental precautions

Steam Cleaning

l  Substrate Types –  Iron Alloys –  Steel Alloys –  Copper Alloys –  Some Al Alloys

l  Typical Uses –  Tanks and Voids –  Piping Systems –  Removing Preservatives

l  Advantages –  Can soften/loosen old paint –  Residual salt removed –  No chemicals involved –  Penetrates pits –  Quick removal of deposits

on large areas

l  Disadvantages –  Limited shipboard uses –  Need source of steam

Pickling (SSPC-SP 8)

l  Substrate Types –  Iron Alloys –  Steel Alloys

l  Typical Uses –  Shop use for mill scale

removal on large steel plate shapes

l  Advantages –  Complete mill scale and

rust removal

l  Disadvantages –  Shipyard/industrial use only –  Environmental and health

precautions –  Not effective for oil and

grease removal –  Cannot use on aluminum or

stainless steel

Alkaline Cleaning

l  Substrate Types –  Iron Alloys –  Steel Alloys

l  Typical Uses –  Bilge cleaning –  Tank cleaning

l  Advantages –  More efficient/less costly

than solvents –  Removes grease and oil –  Penetrates pits

l  Disadvantages –  Handling/disposal of

solutions –  Complicated procedure –  Cannot use in submarine

bilges –  Cannot use on aluminum


Detergent and Water Cleaning

l  Substrate Types –  Any Metal –  Most non-metals

l  Typical Uses –  Light soil and oil removal

l  Advantages –  Most are environmentally

friendly –  Simple process

l  Disadvantages –  Oily water separators not

effective –  Not effective for heavy oil

or grease

Low Pressure Water Cleaning

l  Generally done at pressures less than 5,000 psi –  Not to be confused with hydroblasting or water-jetting

l  NSTM Ch. 631, Section 5 calls for use of fresh water washing at less than 5,000 psi after abrasive blasting to remove salts from critical areas and topside surfaces. –  Wash water shall not contain corrosion inhibitors –  See also NSTM Ch. 631, Section 5 for different

requirements for well deck overheads.

Other Surface Treatment Methods

l  Intended for shop use, parts and components l  Pretreatments—intended to provide a better

surface to enhance paint adhesion and performance –  Conversion Coatings: aluminum alloys –  Anodizing: aluminum alloys –  Phosphate Coating: iron, steel, and galvanized surfaces

l  Electrocoating (E-coat): metallic substrates

Summary

l Defined solvent, chemical, steam, and detergent/water cleaning as a means of cleaning ship surfaces prior to coating

l Described those cleaning methods according to NSTM Chapter 631, Section 5

Topics• Hand and power tool cleaning• Power tool cleaning to bare metal• Factors affecting surface preparation

Scope This section gets students acquainted with methods of mechanical cleaning and when they are most commonly used on ships.

Learning Outcome At the end of this section, students will be able to discuss the operational and safety aspects of mechanical cleaning tools and recognize the specifications for mechanical cleaning methods.

6 Mechanical Cleaning Methods

HAND AND POWER TOOL CLEANING (SSPC-SP 2 AND SSPC-SP 3)

These specifications remove ONLY loosely adhered surface contamination. They do not remove tightly adherent paint, rust, and weld spatter. Both standards, SSPC-SP 2 and SSPC-SP 3, only require that loose debris be removed. “Tightly adherent” debris is defined as mill scale, rust, and paint that cannot be removed with a dull putty knife.

Hand tools, covered by SSPC-SP 2, are best used in areas where corrosion is not serious—and are especially useful in areas inaccessible by power tools, or for relatively small touch-up jobs where abrasive blasting is not practical. Power tool cleaning, as specified by SSPC-SP 3, is best used for preparation of larger areas. As with hand tools, it is most effective where corrosion is not serious.

NSTM Chapter 631, Table 631-1-6 calls for hand or power tool cleaning for “Minimum Spot Repair Surface Preparation.”

• Use solvent or detergent to clean area before hand tool cleaning, to remove oil and grease contaminants.

• Use vacuum or proper removal methods to clean up dust and particles. DO NOT DISPOSE OF DEBRIS OVERBOARD!

• SSPC-VIS 3 provides comparative visual guides for hand tool and power tool prepared surfaces. SSPC visual guides are useful when trying to determine if the cleanliness requirements of the various SSPC hand and power tool specifications have been met.

NAVSEA Basic Paint Inspector Training: Mechanical Cleaning Methods

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General Safety Requirements• Use face shield or goggles to protect from flying debris.• Tape over sharp edged tools when carrying them around.• Wear protective gloves.• If working above other personnel, tie tool to belt or structure.

Paint Scraper Use by pushing or pulling across surface. Do not strike surface with this tool, since it will dent the surface and embed contaminants.

Chipping Hammer Unlike a carpenters hammer, this hammer has a squared-off edge. This edge should not be sharp. It is especially useful for removing weld slag and loose weld spatter. The chipping hammer is used by striking the surface, but only hard enough to loosen the debris. It should NEVER be used on aluminum, thin steel, or piping.

Putty Knife Putty knives can be used to determine if a coating is well adhered to a substrate. Do not damage sound coatings or substrates during use.

Wire Brushes Use on light rust, after heavier contamination has been removed. If many bristles are bent, the brush will be much less effective. Bristles should not be contaminated with oil or grease.

Wire brushes must also be compatible with the substrates on which they are being used. Use only stainless steel brushes on aluminum or stainless steel surfaces, or corrosion will occur due to embedded particles of dissimilar metals.

Carbon steel brushes can cause sparks. Use only copper alloy or stainless steel brushes on steel surfaces if a non-sparking brush is required.

Abrasive Cloths and Papers Sandpaper is very useful for feathering edges of surrounding intact paint. Garnet, aluminum oxide, and silicon carbide are most common types. Various grades are available, ranging from “00” to “400” and finer.

Non-Metallic Pads/Mats (“Greenie Pads”) Useful for removing light corrosion products, rust stains, and chalking on epoxy paints.

HAND AND POWER TOOL CLEANING (continued)

BECAUSE OF THE RISK OF SURFACE CONTAMINATION DO NOT USE ON:

• Aluminum• Stainless Steel

CARBON STEEL WIRE BRUSHES

REMEMBER:

• Solvent cleaning, as specified in SSPC-SP 1, is required before beginning hand or power tool cleaning.

• Hand or power tool cleaning is not as good as blast cleaning—life expectancy of the coating will gen-erally be reduced.

• All SSPC surface preparation stan-dards can be found in Appendix F

Navy Basic Paint Inspector Training: Mechanical Cleaning Methods

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POWER TOOL CLEANING TO BARE METAL (SSPC-SP 11)

Power tool cleaning to bare metal, SSPC-SP 11, as its name implies, requires the removal of all rust, loose mill scale and paint to bare metal. Additionally, unlike SP 3, SP 11 requires a surface profile of at least one mil on the prepared surface. This specification is commonly used for spot repair and touch-up of disturbed coatings in lieu of requiring SP 10 for these small areas. Because of the labor involved in achieving this degree of cleanliness it should be reserved for small, mildly corroded areas only—time and cost associated with SP 11 will go up dramatically as the area and severity of corrosion increase. Note that the specification does not specify a method for achieving a one mil profile—any mutually acceptable tools may be used.

For surface ships, NAVSEA Standard Item 009-32, Section 3 (paragraph 3.10.6.2) requires that the surface profile generated by power tool cleaning to SSPC-SP 11 shall be 2 mils minimum for critical coated areas and 1 mil mini-mum for all other areas where accessable.

Some other advantages of SP 11 include the ability to remove or reduce sharp corners and to smooth excessively rough surfaces. Vacuum shrouded tools are available to reduce dust and particles and to assist in collecting hazardous debris. Be sure to store vacuum shrouded tools properly to maintain the brushes.

Due to the potential for excessive metal loss, for SSN-21 and SSN-774 Class submarines, only the following power tools may be used to obtain an SSPC-SP 11: needle guns and roto-peens. For submarines, 1 mil profile is acceptable for all areas.

As with other SSPC surface preparation methods, SSPC-SP 1 shall be used to specify solvent cleaning to reduce surface contamination prior to power tool cleaning.

Examples of power tools (Figure 6-1): Roto-peen, Needle Gun, Disk Sanders, and Deck Abraders

Figure 6-1: Typical Power Tools

SHROUDED POWER TOOLS

• Many power tools are available with vacuum shrouds to help control dust and allow for automatic debris col-lection


6—4

Poor surface preparation is responsible for at least 75% of all paint failures. There are techniques which can be used during the substrate surface preparation stage which will provide better adhesion with the coating and are explained in detail in SSPC PA Guide 11, Protecting Edges, Crevices, and Irregular Steel Surfaces by Stripe Coating.

Feathering the edges of old coatings (Figure 6-2) provides a smooth transition between existing paint and bare metal to prevent cracking due to film shrinkage when paint cures. It also removes top layer of alkyd when applying epoxy touch-up.

Figure 6-2: Feathering the Edges of Old Coatings

Commercial grade power tool cleaning (SSPC-SP 15) requires removal of all visible oil, grease, dirt, rust, coating, oxides, mill scale, corrosion products, and other foreign matter. Random staining shall be limited to no more than 33 percent of each 9 in2 surface area, and may consist of light shadows, slight streaks, or minor discolorations caused by stains of rust, stains of mill scale, or stains of previously applied coating. Slight residues of rust and paint may also be left in the bottoms of pits if the original surface is pitted. In addition, SP 15 requires a minimum surface profile of 1 mil (25 micrometers).

Rotary impact flap tools, needle guns, cutter bundles, hammer assemblies, and some types of sanders and grinders may be used to achieve an SP 15 cleanliness level.

As stated in NAVSEA Standard Item 009-32: for nonskid areas that abrasive blast equipment or waterjet equipment cannot access, substrate shall be prepared to SSPC-SP 11, except that minimum profile shall be 2 mils where accessible. Underside of tie-down bars shall be prepared to SSPC-SP 2 or SSPC-SP 3, however feathering requirements are waived, while remainder of tie-down shall be prepared to SSPC-SP 15.

COMMERCIAL GRADE POWER TOOL CLEANING (SSPC-SP 15)

FACTORS AFFECTING SURFACE PREPARATION

Navy Basic Paint Inspector Training: Mechanical Cleaning Methods

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Smoothing irregular weld seams and spatter:• Grind welds and weld spatter smooth to provide flat surface.• Coatings will not cover sharp or porous weld splatter effectively.

Weld slag removal:• Weld slag and oxides will have low adhesion and could cause crevices

and voids which may cause paint failure.

Scuff sanding of intact paint:• Provides for greater adhesion of topcoat by roughening the smooth sur-

face of existing top coats.

This chapter has described using hand- and power-tool cleaning as a surface preparation method. Hand tools (SSPC-SP 2) are best used in areas where corrosion is not serious. Power-tool cleaning (SSPC-SP 11) is used for spot repair and touch-up of disturbed coatings in small areas. Commercial grade power-tool cleaning (SSPC-SP 15) may be used if approved by NAVSEA technical authority on the bottoms of pad eyes prior to waterjetting. Feathering, rounding sharp corners, smoothing irregular weld seams and removing slag, and sanding intact paint can all assist in better surface preparation.

SUMMARY

Rounding sharp corners:• Allows for appropriate thickness on corners.• Two to three (2-3) mm radius recommended.• New coatings available, e.g. MIL-PRF-23236, TYPE VII High Solids,

which have improved coverage over sharp edges.


Mechanical Cleaning Methods (6)


Surface Preparation

Topics

l Hand and power tool cleaning l Power tool cleaning to bare metal l Factors affecting surface preparation

Scope

l Gets students acquainted with methods of mechanical cleaning and when they are most commonly used on ships

Learning Outcome

l Students will be able to discuss the operational and safety aspects of mechanical cleaning tools and identify the specifications for mechanical cleaning methods

Hand Tool Cleaning

l  Typical Hand Tools –  Paint scraper –  Chipping hammer –  Putty knife –  Wire brushes –  Abrasive cloth or

sand paper –  Greenie pads


Hand/Power Tool Cleaning

l  Covered by SSPC-SP 2 and SSPC-SP 3 –  SSPC-SP 2 “Hand Tool Cleaning” –  SSPC-SP 3 “Power Tool Cleaning” –  Requires that only loosely adhered material be removed –  NO surface profile specified or required –  Best for tight areas and areas where corrosion is not

serious (minimum spot repair and touch-up)

l  Note: difficult to remove weld spatter by specifying SP 2 & 3

Hand/Power Tool Cleaning

l  General Procedure: –  clean area with solvent or detergent prior to hand tool

cleaning (SSPC-SP 1) –  use vacuum or other method to clean up dust and debris –  use clean tools constructed of materials which will not

contaminate the surface being cleaned –  consult SSPC-VIS 3 for comparative visual references

for hand and power tool cleaned steel surfaces l  Note: Hand tool cleaning does not create a profile

SSPC-VIS 3

l  Visual guide l  Used as an aid for

determining if the specified cleanliness level has been attained

l  VIS 3 covers SSPC-SP 2, SP 3, SP 15 and SP 11

SSPC-VIS 3

l  There are starting conditions based on new steel and there are three grades for previously painted surfaces

l  For SP 3 Power Tool Cleaned surfaces, there are different photos for surfaces treated by: –  Power Wire Brush (PWB) –  Sanding Disk (SD) –  Needle Guns (NG)

Power Tool Cleaning to Bare Metal

l  Typical Power Tools –  Roto-peen –  Needle gun –  Disc sanders –  Deck abraders –  Belt sanders


l Rotating Bristle Power Tool



l Covered by SSPC-SP 11 –  Removes all rust and paint to bare metal –  Provides a surface profile (1.0 mil minimum) –  NAVSEA Standard Item 009-32 requires a

minimum 2 mil profile for critical coated areas and a 1 mil minimum for others

–  Vacuum shrouded equipment available to contain dust and debris

–  For heavily corroded areas, can be very expensive


l SSN-21 and SSN-774 Submarines –  Due to potential metal loss only needle guns and

rotopeens may be used to achieve SSPC-SP 11 –  For submarines, preparation to an SSPC-SP 11 with

a 1 mil profile is acceptable for all areas.

Commercial Grade Power Tool Cleaning

l Covered by SSPC-SP 15 –  Intermediate between SP 3 and SP 11 –  Removes all oil, grease, dirt, rust, mill scale, coating,

etc. –  Random staining on no more than 33% of each 9 square

inch of surface –  1 mil minimum profile required –  NAVSEA Standard Item 009-32 requires a minimum 2

mil profile for critical coated areas and a 1 mil minimum for others

–  It is the level of cleaning permitted for tank bolting rings

Power Tool Cleaning

l  Covered by SSPC-SP 3 –  Removes “loosely adherent” material only (loosely adherent

= can be removed with a dull putty knife) –  No minimum profile requirements as in SP 11 and SP 15 –  Burnishing of the surface is not permitted

Power Tool Cleaning

l General Procedure: –  clean area with solvent or detergent (SSPC-SP 1)

prior to power tool cleaning –  use vacuum or other method to clean up dust and

debris –  consult SSPC-VIS 3 for comparative visual

references for power tool cleaned steel surfaces –  ensure proper PPE is used

Feathering

Feathering prevents premature failure of coatings applied over existing coatings.

New Paint!Old Paint!


Feathering with Power Tools Surface Preparation

l  Sharp corners can present a severe coating problem: –  surface tension causes coatings to pull away from sharp

edges –  resultant paint film is too thin, easily broken

l  These problems can be prevented by: –  rounding the corners with a 2-3 mm radius (a time

consuming and expensive process) –  applying edge retentive coatings

l  SSPC-PA Guide 11

Edge Failure of Coating

The coating on the edge of this deck support has failed and corrosion has begun.

Edge Corrosion

Edge Corrosion Weld Joints

l  Welds can be porous, weakly bonded, or have sharp projections

l  Weld spatter is most difficult to remove l  Welds should be ground smooth for optimum

coating performance, often not permitted –  Weld crown may be part of joint design –  NDE may be required after weld grinding

l  Contouring/dressing of weld should be done, if weld is not ground flat


Weld Joints

l  NSTM Chapter 631 provides guidance indicating that welds are to be ground within 1/16-in. of surface of the surrounding metal.

l  NACE visual comparator “Surface Finishing of Welds,” a cast plastic model with varying weld joints and finishes, may be invoked. This standard accompanies NACE SP 0178, Design, Fabrication, and Surface Finish Practices for Tanks and Vessels to be Lined for Immersion Service.

Poor Weld Preparation

The weld seam on this ventilation ducting was not properly prepared and the coating soon failed.!

Summary

l  Described using hand and power tool cleaning as a surface preparation method

l  Hand tools (SSPC-SP 2) are best used in areas where corrosion is not serious

l  Power tool cleaning (SSPC-SP 11) is used for spot repair and touch-up of disturbed coatings in small areas.

l  Commercial grade power tool cleaning (SSPC-SP 15) may be used if approved by NAVSEA technical authority on the bottoms of pad eyes prior to waterjetting

l  Feathering, rounding sharp corners, smoothing irregular weld seams and removing slag, and sanding intact paint can all assist in better surface preparation