Texaco GEMS-V-2P0 Applications of Interior Tank Coating

8/20/2019 Texaco GEMS-V-2P0 Applications of Interior Tank Coating

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DEC 97 APPLICATION OF INTERIOR TANK COATING GEMS V-2P0

PAGE 1 OF 26 ©TEXACO GENERAL ENGINEERING DEPARTMENT

TABLE OF CONTENTSPAGE

1. SCOPE .............................................................. 3

2. REFERENCES ......................................................... 3

2.1 Purchaser Specifications ..................................... 3

2.2 Purchaser Drawings ........................................... 3

2.3 Industry Codes and Standards ................................. 3

3. GENERAL ............................................................ 4

4. DEFINITIONS ........................................................ 4

5. PURCHASER REQUIREMENTS ............................................. 4

6. SUPPLIER REQUIREMENTS .............................................. 5

6.1 General ...................................................... 5

6.2 General Rules for In-Plant Work .............................. 6

7. EQUIPMENT .......................................................... 7

8. MATERIALS .......................................................... 7

9. CLIMATIC CONDITION CONTROL ......................................... 8

9.1 Factors Affecting Application ................................ 8

9.2 Dehumidification ............................................. 9

10. SURFACE PREPARATION ................................................ 10

10.1 General ...................................................... 10

10.2 Precleaning .................................................. 10

10.3 Metal Preparation ............................................ 10

10.4 Abrasive Blast Cleaning ...................................... 11

11. LINING SYSTEMS ..................................................... 12

12. APPLICATION OF COATING SYSTEM ...................................... 12

12.1 General ...................................................... 12

12.2 Preparation of Coatings ...................................... 13

12.3 Brush Application ............................................ 1312.4 Spray Coating ................................................ 14

12.5 Ventilation .................................................. 14

12.6 Tank Bottoms ................................................. 14

12.7 Tank Bottom, Walls, and Roof ................................. 19

13. SAFETY ............................................................. 20

13.1 General ...................................................... 20


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13.2 Solvents ..................................................... 20

TABLES

1 - Thin Film Lining Systems2 - Thick Film Lining Systems3 - Thick Film Reinforced Lining Systems

FIGURES

1 - Welded Seam2 - Riveted Seal3 - Welded Chine4 - Riveted Chine5 - Roof Supports6 - Roof Supports7 - Roof Supports

ATTACHMENTS

V-2P0I Inspection and Testing Requirements Sheet (ITRS)V-2P0R Documentation Requirements Sheet (DRS)

http://v2p0i.doc/http://v2p0r.doc/http://v2p0r.doc/http://v2p0i.doc/


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1. SCOPE

1. This specification, along with API RP 652, defines minimumtechnical requirements for coating interior surfaces of abovegroundwelded steel tanks.

2. This specification does not define requirements for determining theneed for an interior tank coating. Service experience, analysis bymaterials engineer(s), and consultation with coating manufacturersshall be considered.

2. REFERENCES

2.1 Purchaser Specifications

This specification contains references to the following Purchaserspecifications:

1. GEMSGC, “General Conditions - General Equipment and MaterialSpecifications”.

2. GEMS V-1M, “Industrial Coating Materials”.

3. GEMS V-2M, “Interior Tank Coating Materials”.

4. GEMS V-1P, “Application of Industrial Coating Systems”.

2.2 Purchaser Drawings

This specification contains references to the following Purchaserdrawings:

None.

2.3 Industry Codes and Standards

This specification contains references to the following industry codesand standards:

2.3.1 Occupational Safety and Health Act (OSHA)

“Standard for Abrasive Blasting”.

2.3.2 American Petroleum Institute (API)

1. RP 652, “Lining of Above Ground Petroleum Storage Tanks”.

2. 653, “Tank Inspection, Repair, Alteration, andReconstruction”.

3. Publ 2207, “Preparing Tank Bottoms for Hot Work”.

2.3.3 NACE International (NACE)

1. #1, “Surface Preparation Grade 1 (White)”.

2. 6F264, “Recommended Safety Inspection Check List for

Application of Interior Linings”.3. RP0178-89, “Fabrication Details, Surface Finish

Requirements, and Proper Design Considerations for Tanksand Vessels to be Lined for Immersion Service”.

4. 6D163, “A Manual for Painter Safety”.

2.3.4 Steel Structures Painting Council (SSPC)

1. PA-2, “Measurement for Dry Paint Thickness with MagneticGages”.


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2. PA Guide 3, “A Guide to Safety in Paint Application”.

3. SP-1, “Solvent Cleaning ”.

4. SP-5, “White Metal Blast Cleaning ”.

5. SP-7, “Brush-Off Blast Cleaning ”.

3. GENERAL

1. Unless specified otherwise, surfaces to be coated shall includenozzles, interior face of blind flanges, and manway covers.

2. Coating systems for tank exteriors shall comply with GEMS V-1M andV-1P.

3. Used tanks that require structural repairs shall be inspected andrepaired in accordance with API 653 before work for interiorcoatings may begin. Consideration shall be given before coating thevapor space of an old tank, as it may not be feasible to clean andsafe to weld in the superstructure.

4. General conditions shall comply with GEMSGC.

4. DEFINITIONS

1. Desiccant - Solid or liquid material that has ability to collectmoisture from air and later release water vapor if material isheated.

2. Gas free - Suitable for entry without wearing a respirator.

3. Relative humidity - Ratio, expressed as a percentage, of amount ofwater vapor present in a given volume of air at a given temperatureto amount required to saturate air at that temperature.

4. Wet-bulb temperature - Temperature of air flowing across athermometer with its sensing bulb surrounded by a wetted wick.Water evaporating from wick cools the sensing bulb in proportion to

amount of evaporation. Evaporation effect, and therefore thecooling effect, is greater if air is drier. By measuring wet anddry bulb temperatures and plotting the values on a psychrometricchart, amount of moisture in the air can be determined.

5. PURCHASER REQUIREMENTS

1. Unless specified otherwise, Purchaser will provide electrical powerat the project at the nearest source. Electrical power requirementsshall be specified by Supplier.

2. Route of entry and exit to the project will be designated byPurchaser.

3. Purchaser will ensure that the tank is cleaned and free of gas. All

covers will be removed from cleanouts and manways.4. Unless specified otherwise, Purchaser will be responsible for all

welding repairs to the tank.

5. Floating roof pontoons shall be checked with a combustible gasindicator. If an explosive mixture is found, pontoons shall be madegas free before any work is performed on the tank.

6. Suction and fill lines shall be blinded.


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7. Potable water as required by all trades needed to perform thesubject work may be furnished by Purchaser at its nearest source.

8. Where fire hydrants are available, Purchaser will provide a firehose. Fire hose shall be connected to the nearest fire hydrant and“strung out” to the project. At the end of each work day, Suppliershall ensure that the hose is depressured.

9. Unless specified otherwise, Purchaser will test the used blastmedia. If used blast media is nonhazardous, Supplier shall disposeof it. If used blast media is hazardous, Supplier shall place it inapproved containers supplied by Purchaser for ultimate disposal byPurchaser.

10. At any one time, no more than two large containers, such asrolloffs, will be provided.

6. SUPPLIER REQUIREMENTS

6.1 General

1. Work not defined in this specification shall be performed inaccordance with the recommendations of manufacturer of coating

system.

2. Portable buildings necessary to provide for office space, storageof tools and material, sanitary facilities, etc., shall beprovided.

3. Sanitary arrangements for workers shall be provided. Thesefacilities shall be serviced during the course of work and removed,along with their contents, upon completion of work.

4. Ventilation shall comply with SSPC PA Guide 3.

5. A fire extinguisher classified for fires related to the scope ofthis work shall be provided.

6. Supplier shall abide by Purchaser safety procedures.

7. Work area shall be kept in a clean and safe condition at all times.At the end of each day, all buckets and cans shall be removed fromthe area.

8. Coatings, thinners, and solvents, including rags and waste solidswith these materials, shall be kept in tightly closed containerswhile not in use. Trash material shall be properly identified anddisposed.

9. Waste byproducts from the project shall be removed.

10. Labor, equipment of adequate capacity and design, and materials(unless otherwise specified) to perform the work shall be provided.

11. Personnel shall be qualified and certified in accordance with stateand/or federal agencies to perform the task to which they are

assigned. Purchaser has the right to refuse to allow any personnelto operate any equipment for which they are not qualified.

12. Blast media shall be subject to approval by Purchaser.

13. Only coating products supplied or specified shall be used.

14. A responsible and competent person in charge of the work who willremain on the project shall be present at all times duringperformance of the work.


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15. One person shall have a radio for a “voice and visual” safety watchwhen someone is working inside the tank.

16. Environmental practices employed in all phases of the work shallcomply with EPA regulations and state or local air quality boardregulations.

17. Costs to clean up any environmental damage caused by Supplier

procedures and work practices shall be borne by Supplier.

18. At the end of the work, debris shall be removed and site shall bereturned to its original or better condition.

6.2 General Rules for In-Plant Work

1. Safety and work rules and regulations established by Purchasershall be observed.

2. Supplier shall at all times obtain a daily work permit, ifrequired, while working within the confines of plant. If required,Supplier shall obtain a “hot work” or “safety work” permit.

3. Caution shall be exercised in the movement of heavy equipment onplant roadways. A flag or ground man shall be provided ahead of andbehind heavy moving loads. Cranes that are moved on plant roadwaysshall have booms detached or fully retracted.

4. Activities shall be conducted in such a manner that road damage isavoided. Plant roads and other plant facilities that are damagedshall be repaired and returned to original or better condition.

5. Smoking by Supplier employees shall be permitted only at locationsdesignated by Purchaser. Smoking shall not be permitted whiletraveling in vehicles within plant. Purchaser reserves right toforbid smoking anywhere within plant.

6. At all times, while working within plant, Supplier shall observeand be subject to such rules and regulations as may be issued byplant for:

a. Security reasons.

b. Minimizing fire and explosion risk.

c. Maintenance or restoration of good order (regarding smoking,lighting of matches, maintenance of open fires, intoxication,misconduct, etc.).

7. Supplier shall take steps necessary to ensure his employees oremployees of his subcontractors observe work rules and regulationsat all times while entering, leaving, or working in plant.Violators shall be promptly removed from plant premises uponfailure to comply.

8. Supplier shall coordinate his work schedule with plant's workinghours to minimize schedule problems. Supplier working hours shallbe subject to approval by Purchaser.

9. Supplier shall include provisions of this specification in everysubcontract such that provisions will be binding upon Supplier andhis subcontractors, agents, employees, and independent contractors.

7. EQUIPMENT

1. Compressed air for blasting and coating application shall be freeof moisture and oil.


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2. Suitable air filters and traps of sufficient capacity shall beincorporated in blasting and spray equipment. Air at nozzle shallbe checked periodically with a blotter test to ensure the air isfree of oil and water.

3. Air spray equipment shall have double pressure regulation forseparate and independent control of fluid and air pressures.

4. Mechanical agitation, spray guns, fluid tips, orifices, and needlesshall be equal to those recommended by coating manufacturer.

5. Brushes and rollers shall be equal to those recommended by coatingmanufacturer.

6. Scaffolding or staging used for surface preparation and coatingshall be subject to Purchaser approval.

7. Equipment shall be easily and readily accessible for correctapplication and inspection of all surfaces. Purchaser shall beallowed use of Supplier's scaffolding and staging to performinspections. Equipment shall be designed such that operators willbe able to stand erect with body and arms free of scaffolding orstaging and structure to be worked on.

8. Generally, round or oval brushes shall be used to coat rivets, boltcorners, and rough, irregular surfaces. Flat brushes shall be usedon flat surfaces.

9. Lambs wool rollers with phenolic cores are the only acceptablerollers unless Supplier can prove to satisfaction of Purchaser thatan alternate roller will work properly.

10. Supplier's temporary wiring, receptacles, lights, etc., shall beweatherproof, explosion-proof, if required by Purchaser, andNEMA/NEC approved for the purpose used. Light bulbs used shall beprotected by NEMA approved steel wire guard.

11. Nozzles used for blasting shall be grounded to tank groundingsystem. Airless spray guns shall have a ground wire connecting gunwith tank grounding system.

8. MATERIALS

1. Materials furnished shall be subject to Purchaser inspection andapproval prior to commencement of work.

2. Coating materials shall be delivered in unopened, clearlyidentifiable containers.

3. Unless expressly approved by Purchaser, different coatings shallnot be mixed.

4. Materials shall be properly stored in accordance with Purchaser andmanufacturer requirements.

5. Thinning of coating materials shall not exceed limitations

established by manufacturer.

9. CLIMATIC CONDITION CONTROL

9.1 Factors Affecting Application

9.1.1 Temperature

1. Coatings shall not be applied if:


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a. Temperature of steel or coating material is below 50°F(10°C).

b. Air temperature is below 50°F (10°C) or above 120°F(49°C).

c. Surface temperature is expected to drop to 50°F (10°C)before coating has dried.

2. Coatings shall not be applied to steel which is at atemperature that will cause blistering or porosity or willbe detrimental to the life of the coating.

3. If coatings are applied in hot weather or thinned in coldweather, precautions shall be taken to ensure thatspecified thickness of material is obtained.

9.1.2 Moisture

1. Coatings shall not be applied in rain, snow, fog, or mist.

2. Coatings shall not be applied if steel surface temperatureis less than 5°F (2°C) above dew point or relativehumidity exceeds 80%.

3. Coatings shall not be applied to surfaces that show tracesof moisture as condensation or precipitation.

9.1.3 Humidity

Manufacturer's instructions shall be followed regardingacceptable humidity range for application and curing ofmoisture-cured coatings.

9.1.4 Measure of Ambient Conditions

1. Measurements of temperature, humidity, and dew point shallbe taken at the project at the beginning of each work dayand every 4 hours thereafter or sooner if weatherconditions appear to be changing.

2. A record of these measurements shall be kept, indicatingthe wet and dry bulb temperature, relative humidity, dewpoint, and surface temperature of the metal of itemscoated.

3. Supplier shall have a “Psychrometric Chart”, shown below,at his disposal at all times on the project.

a. The dew point is the temperature at which moisturewill condense on the surface. Coatings shall not be

applied unless surface temperature is a minimum of 5°Fabove this point. Temperature shall be maintainedduring curing.

b. For example, if air temperature is 70°F and relative

humidity is 65%, the dew point is 57°F. Coating shall

not be applied unless surface temperature is at least62°F.


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d. Surface temperature of substrate.

7. Measurements in paragraphs 6.a. and b. ensure that the dehumidifier

is reducing air dew point by at least 10°. Measurements inparagraphs 6.c. and d. determine if system is achieving desireddifference between dew point and surface temperature.

8. Electronic instruments are highly recommended for these readings

because accurate measurement is extremely difficult to obtain withmanual equipment.

10. SURFACE PREPARATION

10.1 General

1. Surface preparation shall be performed to provide appropriatecombination of surface cleanliness and anchor pattern that isrequired to establish good chemical and mechanical adhesion ofcoating resin to steel.

2. Abrasive blast cleaning shall be to a white metal finish and complywith SSPC SP-5 and NACE #1.

3. Surface preparation shall be subject to Purchaser inspection andapproval before application of coating.

4. While work is in progress, Purchaser shall be notified at least 4hours in advance of any changes in schedule.

5. Unless authorized otherwise, no surface preparation or coatingsystem application shall be performed in Purchaser’s absence.

6. Surface preparations and coating application shall comply with thisspecification and applicable laws and regulations. In the event ofconflict or disagreement, Purchaser will decide which will govern.

10.2 Precleaning

1. Before blasting, all oil, tar, grease, salt, and other contaminantsshall be removed from the surfaces to be coated or lined.

2. Hydrocarbon removal shall be accomplished by either:

a. Solvent cleaning (SSPC SP-1) by power brush and high pressurewater.

b. Steam cleaning using proper chemicals.

3. Cleaning shall be followed by a fresh water rinse to ensurecomplete removal of soluble salts and cleaning chemicals.

4. If entire tank is to be coated, all rafters, supports, andsuperstructure shall be included in cleaning process.

5. A “black light” may be used to locate undetectable hydrocarboncontaminants.

6. Blasting shall proceed only after inspection and approval byPurchaser.

10.3 Metal Preparation

1. If welding repairs, which are normally Purchaser’s responsibility,are specified, the following shall apply:

a. All welding shall comply with NACE RP01, using WeldPreparation Designation “D” as a minimum.


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b. Welds shall be inspected before abrasive blast cleaning forcoating. Under certain conditions (determined by Purchaser),blasting may be necessary for inspection.

c. Inspection shall be made in Purchaser’s presence. Additionalwelding may be required to meet Purchaser standards.

d. Seal welding is recommended. If entire tank is to be coated,

Purchaser will specify whether joints in tank vapor space areto be seal welded.

e. Striker plates shall be inspected and repaired or replaced.

f. If lining the bottom of a used tank, all holes over 1 inch indiameter and all areas with a cluster of small holes or deeppits shall be repaired by patching with 3/16 inch to 1/4 inchsteel plate with a continuous (seal) weld seam.

g. To prevent accidental fires or explosions, hot work repairsshall be made in strict compliance with API Publ. 2207.

h. Welds, weld spatter, lamination in plates, and gross surfaceimperfections shall be ground with abrasive wheels or discs.

i. Weld spatter shall be removed by grinding or chipping, leaving

no spherical deposits. A mounded profile is acceptable.

j. Plate edges shall be rounded to a minimum radius of 1/8 inch.

k. Weld seams shall be ground such that slope onto, across, andaway from bead is gradual but not necessarily flush withplates.

l. Areas to be ground may be preblasted.

2. Blasting specified for coatings shall follow grinding of welds,etc.

3. If lining bottom of tank with a floating roof, before blastingbegins, underside of roof and 7 feet up shell shall receive a brushblast (SSPC SP-7) to remove contaminants and loose scale.

10.4 Abrasive Blast Cleaning

1. Blast cleaning shall be performed by an experienced four man(minimum) crew with equipment and abrasive acceptable to Purchaser.Purchaser reserves the right to reject operators who are notexperienced or competent.

2. Only dry blasting, using compressed air blast nozzles, shall beallowed, unless wet blasting is required by local regulations andapproved by Purchaser.

3. Compressed air supply used for blasting shall be free of water andoil.

4. Air compressors shall have a minimum capacity of 375 CFM per blastnozzle, with a minimum nozzle pressure of 90 psi. Adequate

separators and traps shall be provided and kept empty.

5. Abrasive shall be selected to produce necessary profile or anchorpattern for coating to be applied. Abrasive shall be free ofcontaminants, such as water soluble salts, dirt, clay, oil, andgrease. Used abrasive shall not be reused.

6. Unless approved otherwise, blasting shall be done during daylighthours only on surfaces that will not be wet after blasting orbefore coating.


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7. If blasting is allowed at night, surfaces shall be swept clean thenext morning with light blasting to provide original specifiedsurface condition.

8. Blasting shall not be allowed if metal surface are less than 5°Fabove the dew point temperature of air or relative humidity isgreater than 85%.

11. LINING SYSTEMS

1. Lining systems are identified in three categories:

a. Thin film.

b. Thick film.

c. Thick film reinforced.

2. Maximum design temperatures for the systems are listed in Tables 1,2, and 3. Specific recommendations for service shall be made onlyby manufacturer of system.

3. Lists of recommended manufacturers are contained in GEMS V-2M.

12. APPLICATION OF COATING SYSTEM

12.1 General

1. Coating shall begin as soon as surfaces are properly prepared andprior to formation of any form of corrosion contamination fromatmospheric moisture.

2. Blasted surfaces shall be absolutely clean and dry prior toapplication of the first coat.

3. Spent blast media shall either be removed or adequately coveredprior to coating to prevent contamination of surface to be coated.

4. No abrasive shall be permitted in coating. Workers shall takeprecautions (changing or dusting shoes and removing abrasive from

pant cuffs) to ensure that cleanliness is maintained throughoutentire coating operation.

5. If prepared surface becomes dirty or rusty before first prime coatis applied, surface shall be recleaned to degree initiallyspecified.

6. Surface ready for coating shall be subject to Purchaser approvalbefore coating is begun.

7. Welds and edges shall be stripe coated with primer by brushapplication prior to application of first prime coat.

8. Primers and coatings shall be applied free of holidays, pinholes,runs, and sags to a uniform thickness.

9. Prior to application of any coat, damage to previous coat shall betouched up with corresponding specified material.

10. Coated surfaces, including striping and touchup, shall bethoroughly dry and clean prior to application of subsequent coatsin accordance with manufacturer’s recommendation for recoat time.

11. Each applied coat shall be subject to Purchaser approval prior toapplication of next coat.

12. Coating thickness shall be minimum dry film thickness (MDFT)specified by Purchaser for particular coat or overall system.


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Maximum dry film thicknesses, if specified, shall be strictlyadhered to.

13. Unless specified otherwise, allowable dry film thickness rangeshall be as specified by coating manufacturer on product datasheet.

14. If, after inspection, coating thickness is deemed insufficient,

necessary additional coating to achieve required film thicknessshall be applied. If coating is too thick and detrimental tointegrity of system, excess coating shall be sanded off to requiredfilm thickness.

15. Dry film thickness (DFT) shall be determined using methods outlinedin SSPC PA-2.

16. Each coat shall be allowed to dry and cure thoroughly beforeapplication of subsequent coats. Time between coats shall be thatrecommended by manufacturer for any given temperature.

17. If abrasive or other contaminants have contaminated coating,coating shall be repaired. Supplier and Purchaser shall agree upona suitable repair method that removes all contamination and rendersall damaged coats whole.

18. If improperly mixed coatings (e.g., wrong catalyst or no catalyst)are applied, coating shall be removed. Applicable inspection costsshall be paid by Supplier. If necessary, these conditions shall beinvestigated by coating manufacturer.

12.2 Preparation of Coatings

1. Coatings shall be stirred or mechanically agitated to ensure thatpigments, vehicles, and actuators are thoroughly mixed. Boxing isnot allowed. If required, coatings shall be continuously stirred bymechanical agitators or Purchaser approved means.

2. Coatings shall be thinned only with thinner recommended bymanufacturer and in quantities not exceeding manufacturer’srecommendation. No deviation from quantity of thinner recommended

shall be permitted without prior approval of Purchaser.

3. Tinting for color contrast of primer and mid coat shall be subjectto Purchaser approval for thin film coating application.

4. Pot life shall not exceed limits specified by manufacturer for anybatch. If this limit is reached, material shall be discarded andnew material mixed.

12.3 Brush Application

1. Rollers shall be of a style that will permit material to be appliedefficiently and uniformly.

2. Width of roller and length of nap shall comply with coatingmanufacturer's recommendations or be subject to Purchaser approval.

3. Roller fuzz, if left in coating, shall be removed. Damage tocoating shall be recoated.

12.4 Spray Coating

1. Spray coating shall be performed by operators thoroughly familiarwith application techniques. Purchaser reserves the right to rejectoperators not experienced or competent.

2. Spray equipment (conventional or airless) shall be:

a. Capable of atomizing coating.


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b. Suitably controlled with pressure regulators and gages.

3. Air lines, material lines, spray guns, air caps, nozzles, andneedles shall be those best suited for the product, as recommendedby manufacturer.

4. Traps or separators shall be provided to remove oil and condensedwater from compressed air. These traps or separators shall be

drained periodically or continuously during operation.

5. Coatings shall be kept properly mixed by continuous mechanicalagitation in spray pots or containers during application.

6. Pressurized containers shall be fitted with pressure gages andsafety valves. Safety valves shall be tested daily before use.

7. Pressure on material in pot and air pressure at gun shall beadjusted for optimum spraying effectiveness. Air pressure at gunshall be high enough to properly atomize coating. Pressure shallnot be so high as to cause excessive fogging of material, excessivesolvent evaporation, or loss due to over spraying.

8. If necessary, a brush shall be used to ensure that all crevices,pits, and corners receive adequate coverage.

9. Welds shall be given a stripe brush coat of primer prior to sprayapplication.

10. Runs or sags shall be brushed out immediately, or coating shall beremoved and surface resprayed.

11. Spray equipment shall be kept clean of dirt, dried coatingmaterial, and other foreign substances. Solvents used for cleaningshall comply with manufacturer's recommendations and be completelyremoved from equipment before use.

12.5 Ventilation

1. During and after application, thorough air circulation shall beprovided until coating is cured.

2. No tank shall be lined unless it has at least two openings forproper air circulation.

3. If possible, air circulation shall be fresh air intake at top oftank and exhaust at bottom by suction fans. This requirement isnecessary because solvents used in coatings are heavier than airand will settle at bottom of tank.

4. Exhaust shall be capable of preventing solvent vapor concentrationfrom reaching lower explosive limit for solvents used.

5. Ventilation shall be used for a minimum of 4 hours after final coathas been applied to remove flammable solvents.

12.6 Tank Bottoms

12.6.1 General

1. Prior to priming, the following shall be prepared inaccordance with Section 3:

a. Bottom metal surfaces.

b. Equipment within tank.

c. Lower 2.5 feet of shell.

d. Lower 2.5 feet of all fixed roof support legs.

2. All welding and grinding shall be completed.


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3. Dehumidification is recommended.

12.6.2 Priming

1. Prepared surface shall be subject to Purchaser approvalprior to primer application.

2. Striping of all welds and edges shall be completed before

general application of primer begins.3. Blasted surface shall be primed within 8 hours or as

needed to prevent flash rusting and protect the blast. Ifrusting or flash rusting occurs, surface shall bereblasted to specified finish.

4. Prepared surface shall be rendered dust-free prior toapplication of any prime coat by blowing off surface withclean, dry air, preferably with an industrial vacuumcleaner.

5. Cleaned surface shall be coated with at least one coat ofprimer during the work day it is cleaned and beforeformation of any form of corrosion or contamination fromatmospheric moisture (this requirement may be waived by

Purchaser in dry climates).6. A minimum of 4 inches around edge of prepared areas shall

be left uncoated unless adjoining a coated surface, inwhich case cleaning shall continue a minimum of 1 inchinto adjoining coated surface.

7. Runs or sags shall be brushed out immediately, or coatingshall be removed and surface resprayed.

8. Steel wet by moisture in any form shall be dried andrecleaned before priming.

9. No acid washes or other cleaning solutions or solventsshall be used on metal surfaces after being cleaned. Thisincludes any inhibitive washes intended to prevent

rusting.10. Thickness of primer shall be checked with a wet film

thickness gage during application to ensure specified dryfilm thickness.

11. After primer has cured, Purchaser will perform a hardnesstest and dry film thickness test prior to release forcontinued work. Entry to tank during this period shall belimited to inspection personnel.

12. Upon reentry, personnel shall wear appropriate foot wearto keep from damaging primer.

12.6.3 Patching

1. Holes up to 1 inch in diameter shall be filled with

putty/caulking and patched with two layers of 1 1/2 ounceglass mat saturated with layup resin.

2. Each patch shall be centered over the hole and extend aminimum of 3 inches past perimeter or all sides of hole.

12.6.4 Putty/Caulking Application

1. Application may be by spray or putty knife and shallinclude chine, bottom plate seams, bottom of sumps, andalong column bases.


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2. Putty used shall be compatible with the resin system (seeSection 11).

3. Corrosion pits in primed steel (shell and bottom) shall befilled with putty flush with substrate surface.

4. Large projections and lap joints on welded plates to becoated shall be filled with putty to smooth out surface

and permit complete contact with laminant system. SeeFigures #1 and #5.

5. Chine or bottom angle shall be filled with putty andcovered to a smooth 3 inch radius to permit contact withlaminant system. See Figure #3.

6. Riveted seams, lap joints, and chine angle plates shall befilled with putty and smoothed to obtain complete contactwith laminant system. See Figures #2 and #4.

12.6.5 Columns, Support Legs, Sumps, Etc.

1. For tanks on which column base is not fixed or attached tobottom by welds, a striker plate and resin laminant patchshall be placed under column base as follows:

a. Plates shall be installed under fixed roof tanks oneat a time. No fixed roof support shall be raised whileanother is on the jack.

b. Tack welds and/or guides shall be removed to freecolumn base and provide a smooth tank bottom.

c. Column base shall be jacked up in accordance withinstructions detailed in Figures #5, #6, and #7.

d. If a coating system is used without reinforcing,“coating system” shall be inserted in step 6 insteadof “reinforced laminant” in Figure #5.

2. Striker plate for support legs on floating roof tanksshall be placed as follows:

a. Tanks normally have a stationary striker plate with acircumferential fillet weld as part of originalconstruction (see Figures #5, #6, and #7). If thisstationary plate is not a part of design, steps 5 and6 shall be eliminated, and reinforced laminant (orcoating system) shall be applied directly to blastedand primed steel bottom, ensuring it extends 12 inchesonto floor. Steps shown in Figure #7 shall then becontinued.

b. Auxiliary striker plate shall be blasted, primed, andplaced into wet laminant. Support legs shall belowered on auxiliary striker plate when resin startsto gel.

c. Hollow legs shall be wrapped with plastic, secured toprevent dripping during transfer to a temporarysupport, and raised.

d. Reinforced laminate (or coating system) shall extendat least 12 inches in all directions from strikerplate such that there is a 3 inch overlap when layupoperation is continued across the floor.


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3. Sumps shall receive a reinforcement layer across bottom,up sides, and 6 to 12 inches onto floor.

4. Additional layers of laminant shall be installed on tankbottom as follows:

a. Under gage hatch (4 foot by 4 foot area).

b. Fill line outlet (4 foot by 4 foot area).

c. Swing line arresting chain of floating roof tanks (3foot by 12 foot area).

12.6.6 Application of Laminating Resin

1. Lower Shell

a. Layup operation on shell shall proceed in accordancewith paragraph 2. and shall continue around entiretank circumference, sumps, and column bases or legpads before laying the tank bottom.

b. Laminant shall be laid up shell 24 inches and extend24 inches onto tank bottom, with a lap joint of 3inches.

c. Glass shall be completely wet and sealed on top edge.

d. Resin shall be extended 4 inches past top edge ofglass.

2. Tank Bottom

a. Supplier shall refer to manufacturers’ recommendationsfor specific equipment and detailed instructions forapplication.

b. Layup operation across tank bottom shall, in general,be accomplished in successive parallel courses of 50inch widths and 20 foot lengths of glass mat,providing a minimum lap joint of 3 inches.

c. Reinforcement shall be placed without stretching orpulling in widths not to exceed 50 inches.

d. Any area of reinforcement found torn or damaged shallbe cut to remove damaged area and that piecediscarded.

e. General layup process across tank bottom shall requirethe following procedure:

(1) Roll or spray a heavy coat of catalyzedlaminating resin on primed steel surface.

(2) Lay sections of glass mat into resin and compressit into wet resin with ribbed roller smoothingout all of folds and wrinkles.

(3) Apply additional layup resin as needed tocompletely wet all glass fibers and mat.

(4) Before resin gels, work wet laminant with aroller, ensuring complete resin saturation ofglass fibers and that wrinkles, folds, airbubbles, and entrapment are released prior toresin cure.

(5) During resin and mat application, check to ensureuniform wetting and prevent resin rich (puddling


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or surplus resin) or resin starved areas (lack ofresin and poor wet-out of glass fibers).

f. If chopped glass is being used, operation shall followsame basic guidelines as layup operation.

g. Normally, chopped glass and resin mixture shall beapplied to a thickness of 55 to 60 mil DFT.

h. Care shall be taken to ensure all fibers are rolledinto resin on wall, as well as floor.

3. Laminant Inspection

a. Inspection procedures in this section shall befollowed prior to applying seal or gel coat.

b. The following test equipment shall be used:

(1) Microtest or Nordsion magnetic DFT gage.

(2) Holiday detector - DC flat 18 inch brush withvariable voltage regulator, Spy Detector orequal.

(3) #934 Barcol hardness tester - Barber company#934.

c. Entire floor and shell shall be visually inspected foruncured resin, bubbles, voids, wrinkles, poorly wettedfiberglass, and puddles. Defects shall be marked withchalk for repair.

d. Entire floor and shell shall be randomly checked withmil thickness gage to ensure system meets specifiedDFT, less thickness of seal coat.

e. For vinyl ester and polyester laminants, floor andshell shall be spot checked with a hardness tester.There shall be a minimum of 30 readings after 24hours.

f. A holiday detector, set at voltage recommended bymanufacturer, shall be used to test for holidays inPurchaser’s presence.

g. Visible defects in coating shall be ground out.Adjacent coating shall be briskly sanded with 40 gritcarborundum or aluminum oxide cloth.

h. Holidays which appear only under electrical testingshall be sanded and patched with a patch of glass matsaturated with resin that extends a minimum of 4inches past edge of defect.

i. Uncured resin, puddles, air pockets, folds, wrinkles,air bubbles, and entrapment shall be cut out andpatched with glass mat saturated with resin thatextends a minimum of 4 inches past defect. These areasshall be filled with putty before patching withfiberglass and resin.

j. Repairs shall be tested with holiday detector andhardness tester after sufficient cure.

4. Seal Coat

a. A 15 to 20 mil seal coat shall be applied to all glassreinforced resin surfaces.


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b. Wax solution shall be added, as recommended bymanufacturer, for polyester and vinyl ester resins.

c. Complete system shall be inspected and retested asoutlined in paragraph 3.

5. Cure

a. Reinforced polyester and vinyl ester shall cure for 24hours and then be tested with a hardness tester. Ifreadings meet manufacturer’s recommendations, tankshall be put back in service.

b. Epoxy reinforced glass systems shall cure for 7 days,with surface and ambient temperatures exceeding 60°Fbefore tank is placed back in service.

12.7 Tank Bottom, Walls, and Roof

12.7.1 General

1. Prior to priming, metal surfaces and equipment in tankshall be prepared in accordance with Section 3.

2. Welding and grinding shall be completed.

3. Supplier shall refer to manufacturer's recommendations forequipment and detailed instructions for application.

4. Dehumidification is recommended.

12.7.2 Priming

1. Priming shall follow procedure in Section 12.6.2.

2. Primer shall be tinted to identify it from next coat.

3. Color quantity and type shall comply with manufacturer'srecommendation.

4. If temperature of steel is below that recommended bymanufacturer for curing or forced curing is desired, thefollowing procedure shall be used:

a. Raise steel temperature to 80°F to 100°F. Indetermining steel temperature, take readings fromfloor, as well as walls and roof.

b. Install indirect gas or oil fired heaters with fansbehind flame/element to produce air in tank of 150°Fto 200°F at a convenient opening. Do not use heatersthat will exceed these temperatures.

c. If possible, install a suction fan in an opening asfar away from input fan as possible.

d. Maintain forced heated air input in accordance withmanufacturer’s recommended time and steel temperaturefor desired cure.

5. Under highly corrosive conditions, after prime coat isapplied, a bead of caulking from 3/4 inch to 1 inch wideshall be applied at periphery of tank (wall to floor) toprevent premature failure due to expansion andcontraction.


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12.7.3 Mid Coat and Top Coat

1. Subsequent coats shall be tinted different colors.Quantity and type of tinting shall comply withmanufacturer's recommendation.

2. Coats shall be applied within manufacturer’s recommendedtiming for recoat, as shown on manufacturer’s data sheet.

3. Coatings shall be washed with water prior to applicationof additional coats if they have been exposed to thefollowing:

a. High humidity.

b. Dust, dirt, oil, or grease.

c. Operating plant conditions for any length of time.

13. SAFETY

13.1 General

1. Proper respiratory equipment and personal protective clothing shall

be employed as necessary.2. Information regarding safety precautions is either attached to this

document and/or found in the following:

a. OSHA Standard for Abrasive Blasting.

b. SSPC PA Guide 3.

c. NACE 6F264.

d. NACE 6D163.

13.2 Solvents

1. Methyl ethyl ketone (MEK), a volatile solvent and degreaser, shallbe used to remove uncured polyester resin with highest regard forpersonal safety.

2. MEK shall not be used for washing of hands or body and shall notcontact the skin.

3. MEK shall not be used in an unventilated area unless Purchaserapproved breathing equipment is worn.

4. MEK peroxide, if used as a catalyst for coating material, shall bestored in polyethylene bottles only.

5. MEK peroxide shall be measured in polyethylene or glass graduatesonly.

6. The following shall be used in confined areas:

a. Explosion-proof lighting and electrical equipment.

b. Nonsparking tools, clothes, and shoes.7. Structures and equipment shall be grounded.

8. Procedures that prevent static electric sparks shall be used.

9. Properly fitted appropriate NIOSH/MSHA approved fresh airrespirators, such as MSA or equal, shall be worn during and afterapplication unless air monitoring demonstrates vapor/mist levelsare within safe limits.


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10. Respirators shall have 1/4 inch I.D. or larger air supply lineconnected directly to proper air source.

11. Suction type exhaust fans and blowers with sufficient CFM capacityto keep solvent vapors below 20% of explosive limit shall be used.

12. Air circulation and exhausting of solvent vapors shall be continueduntil coatings are fully cured to ensure that no potential for

fire, explosion, or health hazard remains.

13. Use of a combustible gas analyzer or “sniffer” shall be required tocheck for a safe level of combustible vapors.

14. Unless specified otherwise, Purchaser will provide continuouscombustible gas monitors inside tank during application of anycoating. If gas monitor sounds, Supplier shall stop all work andimmediately exit tank. No work shall resume until gasconcentrations inside tank drop below monitor set point. Such workstoppage shall be sole responsibility of Supplier and will resultin no added cost to Purchaser.


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©TEXACO GENERAL ENGINEERING DEPARTMENT

TABLE 1

THIN FILM LINING SYSTEMS

Maximum Design Temperature °F - Thin Film Lining Systems

Immersion Fluid Epoxy Epoxy Epoxy Epoxy Epoxy Epoxy Epoxy

Coal Tar Amine Amine

Adduct

Novolac Phenolic Polyamide Polyamidoamine

Ammonium Hydroxide, 10% Ambient Ambient 140 120 Ambient

Ammonium Hydroxide, 20% Ambient 140 120 Ambient

Ammonium Hydroxide, 5% Ambient Ambient 140 120 Ambient

Butanol Ambient 130 160 140

Crude Oil, Sour 140 120 200 275 200 120 140

Crude Oil, Sweet 160 130 200 275 250 120 140

DEA 100 100 140 120

DGA 200 200

Diesel Fuel Ambient 130 130 275 250 Ambient

Ethanol 130 120 150 120

Ethylene Glycol 100 130 150 160 100

Fuel Oil, Heating 140 140 180 275 250 100 140

Gasoline, Leaded Ambient 120 140 200 200 100 140

Gasoline, Unleaded 100 Ambient 120 200 200 140

Hydrochloric Acid, 10%

Hydrochloric Acid, 5%

Jet Fuel 130 140 275 250 140

Kerosene 130 140 275 250 100 Ambient

Lube Oil 100 120 200 275 250 Ambient

MDEA Ambient 180 Ambient

MEA 120 Ambient

MEK Ambient 150

Methanol 120 Ambient 120 90

MTBE, 100% 120 140 250 200

Naphtha 100 120 140 250 200 Ambient

Nitric Acid, 5%

Potassium Hydroxide, 10% 120 150 120 160 AmbientPotassium Hydroxide, 20% 120 150 120 160 Ambient

Potassium Hydroxide, 40% 120 150 120 160 Ambient

Propylene Ambient 140 100 140 100

Sodium Hydroxide, 10% 100 120 180 120 160 Ambient Ambient

Sodium Hydroxide, 20% Ambient 120 180 120 160 Ambient


Styrene, 100% 120 120 120 140

Sulfuric Acid, 10%

Sulfuric Acid, 20%

Sulfuric Acid, 40%

TEG 140 120 200 200

Toluene, 100% Ambient 140 120 140 140

Water, Brine 140 180 200 120 200 120 Ambient

Water, Deionized 140 130 180 200 140 140

Water, Distilled 140 160 180 150 200 140 140

Water, Potable 120 150 Ambient 140

Water, Sea 140 160 200 175 160 140 Ambient

Xylene, 100% 100 Ambient 140 180 150 140


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TABLE 2

THICK FILM LINING SYSTEMS

Maximum Design Temperature °F - Thick Film Lining Systems

Immersion Fluid Epoxy Epoxy Epoxy Polyester Polyester Polysulfid

Amine Bisphenol A Novolac Isophthalic Vinyl EsterAmmonium Hydroxide, 10% 120 180

Ammonium Hydroxide, 20% 130 120 150

Ammonium Hydroxide, 5% 120 180

Butanol Ambient Ambient 120 130

Crude Oil, Sour 150 180 140 120 210 250

Crude Oil, Sweet 150 180 140 120 210 250

DEA 120 120

DGA

Diesel Fuel 120 130 130 Ambient 180 250

Ethanol 100 Ambient 130 130 150

Ethylene Glycol 120 130 130 Ambient 210 150

Fuel Oil, Heating 120 130 130 Ambient 180 250

Gasoline, Leaded 120 130 130 Ambient 130 150

Gasoline, Unleaded 120 130 130 Ambient 130 150

Hydrochloric Acid, 10% Ambient 120 160 140

Hydrochloric Acid, 5% 120 120 160 140 100

Jet Fuel 120 130 130 Ambient 130 200

Kerosene 120 130 130 Ambient 150 200

Lube Oil 120 180 140 Ambient 180 250

MDEA

MEA 130

MEK 120 120

Methanol Ambient 120 Ambient 200

MTBE, 100% Ambient 130 120 Ambient 130

Naphtha Ambient 130 120 Ambient 180 200Nitric Acid, 5% Ambient 120 130 150 120

Potassium Hydroxide, 10% Ambient 130 120 150 120

Potassium Hydroxide, 20% Ambient 130 120 150 120

Potassium Hydroxide, 40% Ambient 130 120 150

Propylene Ambient 130 120 Ambient



Sodium Hydroxide, 40% Ambient 180 140 160 180

Styrene, 100% 120 Ambient Ambient

Sulfuric Acid, 10% 120 120 Ambient 210

Sulfuric Acid, 20% 120 120 210


TEG 120 120

Toluene, 100% Ambient 120 Ambient

Water, Brine 140 180 140 180 120

Water, Deionized 100 130 130 Ambient 210

Water, Distilled 100 130 130 Ambient 210

Water, Potable 150

Water, Sea 140 180 140 Ambient 210 180

Xylene, 100% Ambient 120 Ambient 180


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TABLE 3

THICK FILM REINFORCED LINING SYSTEMS

Maximum Design Temperature °F - Thick Film Reinforced Lining Systems

Immersion Fluid Epoxy Epoxy Epoxy Polyester Polyester

Amine Bisphenol A Novolac Isophthalic Vinyl Ester

Ammonium Hydroxide, 10% Ambient 120 150



Butanol Ambient Ambient 120 Ambient 150

Crude Oil, Sour 250 180 140 180 250

Crude Oil, Sweet 250 180 140 180 250

DEA 120 Ambient 120

DGA Ambient

Diesel Fuel 250 130 130 150 210

Ethanol Ambinet 130 120 130

Ethylene Glycol 150 130 130 120 210

Fuel Oil, Heating 275 180 130 150 210

Gasoline, Leaded 200 130 130 150 180

Gasoline, Unleaded 200 130 130 150 150

Hydrochloric Acid, 10% 120 120 150 150

Hydrochloric Acid, 5% 120 120 150 150

Jet Fuel 200 130 130 150 180

Kerosene 200 130 130 180 180

Lube Oil 200 180 140 150 150

MDEA 130

MEA 130 Ambient

MEK 120 120

Methanol 200 Ambient 120 120

MTBE, 100% Ambient 130 120 150 150

Naphtha 200 130 120 150 210

Nitric Acid, 5% Ambient 120 150 180

Potassium Hydroxide, 10% Ambient 130 120 Ambient 150

Potassium Hydroxide, 20% Ambient 130 120 Ambient 150

Potassium Hydroxide, 40% Ambient 130 120 150

Propylene Ambient 130 120 Ambient

Sodium Hydroxide, 10% 140 180 120 Ambient 200

Sodium Hydroxide, 20% 140 180 120 200

Sodium Hydroxide, 40% 140 180 140 150 200

Styrene, 100% Ambient Ambient 150

Sulfuric Acid, 10% 120 120 150 210

Sulfuric Acid, 20% 120 120 120 210


TEG 120 180

Toluene, 100% Ambient 120 150

Water, Brine 140 180 140 150 150

Water, Deionized Ambient 120 130 Ambient 180

Water, Distilled Ambient 120 130 150 180

Water, Potable Ambient

Water, Sea 140 180 140 150 200

Xylene, 100% Ambient Ambient 120


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Texaco GEMS-V-2P0 Applications of Interior Tank Coating

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