0105_A_SEWAGE_TANK_INSPECTION_AND_COATING.docx

USNS TRENTON (T-EPF 5)

SEWAGE TANK INSPECTION AND COATING

1. ABSTRACT

0. This item describes inspection, preparation, and recoating of the ship’s Sewage (CHT) Tank, 5-22-1.

1. REFERENCES

1. 8443364_F General Arrangement

1. 630-593-01-603 CHT System Diagram

1. MSC SWIRRR 010 Tank, Void and Cofferdam preservation

1. ASTM D7091 (DFT measurement)

1. ITEM LOCATION/DESCRIPTION

2. Location: Collection, Holding, and Transfer (CHT) Tank 5-22-1

1. GOVERNMENT FURNISHED EQUIPMENT/MATERIAL/SERVICE: None.

1. NOTES:

0. The contractor and all subcontractors, regardless of tier must consult the General Technical Requirements (GTR) to determine applicability to this work item. In performance of this work item, the contractor and all subcontractors regardless of tier must comply with the requirements of all applicable GTRs.

0. The contractor and all subcontractors, regardless of tier are advised to review other work items under this contract to determine their effect on the work required under this work item. Many of the definitions relating to performance of this work item are found in Work Item 0001.

0. Solvents are only to be used for cleaning purposes only. Thinning of the paint will not be allowed for viscosity control or curing. In no case shall the paint be thinned. Thinner or solvents utilized for paint or coating system shall result in a QDR.

0. If the Contractor uses a grit blast method to accomplish work item requirements, then all labor and material costs associated with the level of effort required in monitoring, containment, handling, clean up, processing, temporary storage, recycling, transportation, and disposal, of the spent blast grit generated; shall be included in the bid price of this work item.

0. Specification of Stripe Coating in no way relieves the contractor of the requirement to achieve complete coverage of the tank surface with each of the specified Full Coats. Stripe Coats are additional coats applied to specific areas of the tanks that represent high corrosion risk. Stripe Coats shall not be used to correct holidays or other application defects in the full coats. Spray application of the Stripe Coats shall not be allowed.

1. QUALITY ASSURANCE REQUIREMENTS

1. Contractor shall perform all perform all requirements of this SOW in concurrence with the MSC paint representative.

1. MSCREP reserves the right to perform additional tests or inspections as required to ensure compliance with this Work Item including, but not limited to, Blotter Test, Vial Test, pH Test, Chloride and Conductivity Testing, Non-Visual Surface Contaminant Tests, Adhesion Tests and Sieve Tests.

1. Wrap up inspections and final cleanliness inspection shall be performed by MSC Representatives and Ships Force. Prior to any application of coatings, the area to be painted shall be inspected and approved by the MSCREP and Ships Force.

1. STATEMENT OF WORK REQUIRED

2. Tank Inspections:

0. Access, cleaning, and space entry requirements shall be accomplished via WI 0021. Contractor shall assume three (3) full take flushes with proper disposal. Coordinate with Ship’s Force. Tank is capacity is approximately 30,900 liters IAW Ref 2.2.

0. Contractor shall protect all tank internal components while executing this WI including but not limited TLIs and level switches.

7.1 Install scaffolding inside the Tank as required to safely conduct all works. Provide and maintain adequate lighting for surface preparation, coating and inspection activities.

7.2 Provide all tools, labor and material to remove and replace with new CFM approximate 40 ft CuNi rinse piping with new CFM CuNi schedule-40 piping and schedule-80 aluminum hangars.

1. Pipe shall be drilled to allow proper flushing of Tank.

1. Ensure all piping is isolated from aluminum with gaskets and tef-gel.

1. Remove existing wash down piping hangers. Fabricate and install new hangers. Repair disturbed coating. Ensure bimetallic isolation is maintained.

1. Replace Washdown Isolation Valve, BGW-V-008.

1. Anodes, if installed, shall be removed before surface prep and reinstalled once Belzona Coating has been applied and cured.

7.3 (CHECKPOINT) After complete cleaning, washing and drying to include all horizontal surfaces, internal frames, web frames, flanges, structure and stringers perform a complete structural and coating inspection. Documenting all as-found conditions. Establish Checkpoint for Post Washdown Inspection prior to blasting or mechanical preparation. MSCREP will determine extent of preservation.

7.3.1.1 NOTE: Any additional items found to require attention not specifically called out in this SOW shall be accomplished via CCO.

7.4 Tank Preservation.

7.4.1 As required, Contractor shall provide all tools, material, labor and coatings to remove original coating system, prepare surface, wash and remove all contamination in the surfaces. Contractor shall use mirrors when applying the coating system due to the unique nature of the T-Bar structure of the tank. All materials used shall be non-ferrous and approved for use on aluminum.

7.4.2 Prior to start of work, all blast certifications, current product specifications and material data sheets shall be provided to MSCREP for approval and reference.

7.4.3 (CHECKPOINT) Perform high pressure wash to remove all surface materials. Utilizing a Belzona recommended bio degradable cleaner for use with aluminum, remove surface contamination on the coating from the entire tank.

7.4.4 (CHECKPOINT) Perform the requirements of reference 2.3 to include surface profile inspection and profiling in accordance with Belzona product specifications.

7.4.4.1 Contractor shall completely remove all existing coatings to a bare metal condition. All hangers and other CuNi, CPVC or aluminum accessories shall also be surface prepped and recoated with the two coat Belzona system.

7.4.4.2 Contractor shall install proper isolation materials between dissimilar metals including pipe hangers and hardware.

7.4.5 (CHECKPOINT) Provide a CFM 1-coat stripe and full 2-coat Belzona 5811 (Immersion Grade) type coating system or similar as recommended by the paint representative. Apply the Stripe coat first for all t-bars, snipes, rat holes and weld seams in accordance with the Belzona Representatives recommendations. Stripe coat, First coat, and Second coat shall be different colors, preferable with a stripe coat of grey, first full coat of beige and a second coat of grey. Each individual coating, first and second coats, shall be applied all at once and shall not be piecewise, where the tank shall be coated 100% before the application of the second. KTR shall provide MSC Paint Rep and Port Engineer with a check point prior to each application to include all primer coats and top coats. DFT measurements shall be taken for each individual coat. Any deficiencies in a single coating will require touch up during the recoat window. Stripe coat will not be allowed to be applied in place of touching up each individual coating. Each individual coating SHALL be 100%.

7.4.5.1 (CHECKPOINT) During cold weather conditions, if the temperatures of the substrate drops below the Belzona temperature recommendations, after each application of the Belzona Coating System, the coating must cure out 100% before applying additional coating. If the recoat window time has elapsed, the contractor shall follow the Belzona recommendations for recoat after 72 hours, including brush blasting to provide a frosted appearance to obtain the target profile before applying the additional coating.

7.4.5.2 Contractor shall provide onsite Belzona representative to supervise surface prep, conditions and application of Belzona system, during the time at which it is applied. Belzona Representative shall be onsite for all applications.

7.4.6 Coating shall extend through all tank bulkheads and wrap through the bulkhead pass-through penetrations, tank hatch interior shall be coated with the same system as the tank.

7.4.7 NOTE: Heaters and Dehumidification will be required to dry coating. The aluminum shell plating of the tank has a thickness of 8mm with a high transfer rate of heat. Contractor shall provide environmental control of the tank as to not allow the humidity of the space to affect the application of the coating system or allow the tank to condensate, or for hull sweat to accumulate.

7.5 All work shall be scheduled to not affect Crew Move aboard milestone.

7.6 Renew man-hole cover gasket before closing out tank. Close out of Tank shall be conducted by the Chief Engineer.

8.0 GENERAL REQUIREMENTS: None additional.

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