SO-18-045_SOW_Temp_Hull_Repairs.docx

SO 18-045

TEMP HULL REPAIR

Contract No.

4 Sept 2018

MSC/SJM

USNS SPEARHEAD

(T-EPF 1)

HULL STRUCTURE

CATEGORY “A”

1. ABSTRACT

1.1. This work item describes the temporary repair of two (1) cracked flange and web members on transverse frames 20 and (3) cracked web on stiffeners L14 and L16 in Pump Room 2 (3-16-2).

2. REFERENCES/ENCLOSURES

2.1. References

2.1.1. NAVSEA Drawing 8445369, General Arrangement and Profile Drawings

2.1.2. NAVSEA Drawing 8442868, Material List

2.1.3. NAVSEA Drawing 8442920, Forward Ride Control Foundation Details

2.1.4. NAVSEA Drawing 8442785, Molded Lines And Offsets

2.1.5. NAVSEA Drawing 8442880, Welding Details

2.1.6. NAVSEA Drawing 8442879, JHSV Class Welding Schedule

2.1.7. NAVSEA Drawing 8442878, Standard Structural Details

2.1.8. NAVSEA Drawing 8442883, Structural Side Plate & Stringer Details

2.1.9. NAVSEA Drawing 8442885, Structural Plan Tank Tops & Inner Bottom

2.1.10. NAVSEA Drawing 8442888, Typical Structure Frames Hull Void 8-24

2.1.11. Void 4 Shell Plate Cracks V2 – SPD

2.1.12. EPF-1 Void 4 FR 20 Crack Temp Repair REV P1

2.1.13. MSC Drawing No. 803-7081122, MSC General Technical Requirements (GTR)

3. ITEM LOCATION/DESCRIPTION

3.1. Location:

3.1.1. Pump Room 2 (3-16-2)

3.2. Quantities:

3.2.1. 5 mm Plate ASTM B928 5083-H116, approximately 65 SQ FT

3.2.2. 8 mm Plate ASTM B928 5083-H116, approximately 43 SQ FT

3.2.3. Belzona 1111, approximately 50 SQ FT

3.2.4. Belzona 1321, approximately 11 SQ FT

4. GOVERNMENT FURNISHED EQUIPMENT/MATERIAL/SERVICES

4.1. Government Furnished Equipment (GFE): None

4.2. Government Furnished Material (GFM): None

4.3. Government Furnished Services (GFS): None

5. NOTES:

5.1. The contractor must perform ship check to retrieve accurate measurements and information before conducting work. Measurements for materials in bill of materials table are estimated based on information obtained from Reference Drawings and estimated temporary repair area

5.2. The contractor and all subcontractors, regardless of tier, must consult the General Technical Requirements (GTR’s) 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 GTR's including but not limited to GTR’S 1 through 7, and 21 through 29. GTR’s are provided as reference 2.1.11.

5.2.1. These requirements are provided as reference but may also be downloaded at:

http://www.msc.navy.mil/instructions/pdf/m470016.pdf

5.3. Performance Period: 10 September 2018 – 21 September 2018

5.4. Location: Port Canaveral, FL

5.5. Port Engineer:

Steven Makonis Cell: 757-478-1724 Email: Steven.makonis@navy.mil

5.6. Services and materials not listed as Government Furnished in Part 4.0 shall be furnished by the Contractor. The Contractor shall provide all equipment, labor and material required to accomplish this work item including but not limited to Marine Chemist, staging, space certification, gas free certification, contamination containment, fire watches, removal and reinstallation of all interferences including insulation and deck coverings in way of repairs to effect a complete and finished end result.

5.7. The contractor must submit a Request for Deviation (RFD) to the MSC Representative (MSC REP) for approval for any areas that appearance, function, and strength are impaired. Upon MSC REP approval minor deviations from the drawings will be authorized if the appearance, function, and strength are not impaired.

5.8. The contractor must open, vent and furnish a Chemist to provide gas free certification for spaces requiring hot work. Gas Free chits must also be signed and approved by the ships Chief Mate or his designated representative daily until work is completed.

5.9. Prior to initiating any work on the electrical system, de-energize and tag-out all sources of electrical power to the circuits involved in accordance standard electrical safety practices and MSC Lockout Tag-out Procedure. Restore electrical power upon completion of all aspects of this work item.

5.10. 6061-SERIES ALUMINUM ALLOYS WILL BE CONSIDERED NON SENSITIZED:

5.11. THE SHELL, 5083-SERIES ALUMINUM ALLOYS WILL BE CONSIDERED MODERATELY SENSITIZED

5.12. Shell seams shall be 300mm apart unless a request for deviation is approved by the MSC REP.

5.13. Existing weld seams shall not be used for cut and repair.

5.14. The recommended distance between field weld seams not on shell plating is 100mm (4in).

5.15. The recommended distance between seam and fillet weld is 100mm (4in).

5.16. Where plate and T shapes or friction stir welded extruded planking is used to repair damaged area, in the plan view, the T’s shall be longer than the plate on both sides to allow a minimum of 200mm overlap on both sides. Joints between T’s and shell plate weld seams shall be staggered.

5.17. Inserts shall include cut and insert plate or planking with a minimum of 75mm (3in) radius corners.

5.18. To remove the heat affected zone (HAZ) created by the existing weld and were seam distances cannot be met; the cut for repair shall be 75mm beyond the existing seam.

6. QUALITY ASSURANCE REQUIREMENTS:

6.1. All Inspections and tests shall be performed in the presence of contractor’s representative, MSCREP and ABS Surveyor. Notify the MSCREP, and the ABS Surveyor 24 hours prior to the scheduled inspections and tests

6.2. All work, testing and materials shall be in accordance with the latest SOLAS regulations, ABS Rule Set, IEEE-STD-45, MIL-STD-1310(G), USCG Requirements, and to the satisfaction of and in the presence of the MSC Representative (MSC REP), ABS Surveyor, and Manufacturer’s Representatives (as required).

6.2.1. All disturbed surfaces shall be repaired utilizing approved methods maintaining the water tight, fire tight, or smoke tight integrity of the bulkheads, decks or equipment.

6.2.2. All shipboard structure, hull insulation, sheathing, etc damaged or disturbed by these modifications shall be repaired similar to the original or surrounding materials.

6.3. Welding shall be accomplished using PULSE GMAW to reduce heat in way of welding.

6.3.1. All requests for deviation to the GMAW process will require MSC REP and ABS approval prior to cutting or welding. Approval will be based on the weld procedure specification and controls.

6.3.2. GMAW short circuit transfer process shall not be used for any welding unless previously approved by MSC REP and ABS Surveyor.

6.3.3. Pulse GMAW shall be used on repairs and install where deck plate thickness is 6mm or below.

6.4. The contractor shall provide material certs, welder certs, and an ABS approved, ‘reduced heat’ weld procedure specification (WPS) to the MSC REP and ABS surveyor prior to commencing work required to accomplish this work item.

6.4.1. All material, including prefabricated installations, shall be traceable to the material certifications and verified prior to installation.

6.4.2. The welding sequence shall be included in the WPS.

6.4.3. Where welding to thinner aluminum (6mm thick and below) welder certs shall clearly show welder is certified to weld on/to plate thicknesses in question (i.e. welding 25mm plate to 3mm plate or welding 3mm butt joints will require a weld cert and procedure that shows welder is qualified to complete that work).

6.4.4. Material certified via ASTM/G67 testing may be used up to 12 months from the date of the certification without further testing. If the certification is over a year old, the aluminum must either be retested via ASTM/G67 testing or through surface preparation penetrant inspection (PT), whichever is lower in cost. Surface preparation PT will include 100 percent PT of four (4) inches from the expected weld area. The PT inspected surfaces shall be free of discontinuities such as linear indications or defects that may affect weld quality of the condition of the base material. If discontinuities exist, a condition found report (CFR) shall be submitted to the MSC REP and ABS surveyor prior to fit-up. After inspection the surfaces shall be thoroughly cleaned.

6.5. Ultrasonic Impact Treatment (UIT) shall be used as part of the repair process on the moderately sensitized shell repair.

6.5.1. UIT is not required where testing, by ASTM G67 or In-Situ DoS is completed to support this work item (WI), proves material is not moderately sensitized.

6.5.2. For the application of UIT, a process control procedure (PCP) shall be prepared and submitted by the contractor and shall be pre-approved by MSC REP PRIOR to cropping or renewal of materials.

6.5.2.1. UIT is often used to pretreat materials PRIOR to removal.

6.6. All welds and cutting, to and on, moderately sensitized plate shall meet the requirements for a reduced heat weld process as stated in this work item.

6.7. All welds and cutting, to and on, thin plate shall meet the requirements for a reduced heat weld process as stated in this work item.

6.7.1. Thin plate is considered plate 6mm thick and below.

6.8. All welding requirements shall be accomplished by ABS certified welders and meet MSC REP, ship class welding details, ABS and AWS requirements. All welders shall be certified to perform the type of welding required and documentation of such shall be current. Fire watches shall be posted by the Contractor during hot work.

6.8.1. For aluminum hull:

ABS Rules for Material and Welding (Part 2) – Aluminum and Fiber Reinforced Plastics (FRP) (latest revision).

AWS D3.7.

6.9. Contractor shall ensure heat on new and existing materials is kept to a minimum in way of removal, installation and repair.

6.9.1. Plasma Arc Cutting, grinding wheel and fiber cutting discs shall NOT be used for material cutting unless previously approved by MSC REP.

6.10. The contractor shall use protective enclosures to ensure a draft free environment.

6.11. The contractor shall clean and gas free affected enclosed spaces per SMS Procedure 2.1-010-ALL (Hotwork) as approved by the ship and/or MSC REP.

6.12. The recommended wire is 5183 for welding to 5083. Typical brands that are ABS approved are Lincoln, Alcotech, and Maxal. Contractor shall verify material requirement with the MSC REP and ABS prior to starting any work.

6.13. Circular saws, reciprocating saws, portable band saws, and saber saws can result in good quality cuts when cutting speeds and proper equipment are used. Cut edges shall be smooth, uniform, and free from burrs, tears, and cracks. A rough surface shall be milled, filed, deburred, or sanded to make it smooth. Plasma cutting shall not be used.

6.14. Aluminum surfaces must be thoroughly cleaned within six (6) hours of welding. Cleaning will be no less than a minimum of four (4) inches on both sides from the expected weld area prior to fit-up and welding. Cleaning shall include degreasing, then the oxide film shall be removed manually cleaned using either a carbide burr, stainless steel wire brush, aluminum oxide coated fiber wheel, or abrasive disk. Stainless steel wire brushes used for surface preparation shall be used for aluminum cleaning only. After oxide film is removed, the joint surface and adjacent base material shall be wiped clean with a rag that has been soaked in approved chemical solvent immediately prior to welding.

7. STATEMENT OF WORK REQUIRED

7.1. Arrangements/Outfitting:

7.1.1. The contractor shall design and make all necessary arrangements (scaffolding, safety gear, temporary accesses, install padeyes and lifting gear, rigging path, etc) to safely complete the repair called out in this work item.

7.1.2. Contractor will provide all tools, material and labor to repair hull damage. Only ABS approved materials shall be used in the execution of this work item.

7.1.3. Contractor shall provide divers and cofferdam to accomplish work.

7.1.3.1. Cofferdam shall properly seal exterior of hull to prevent intrusion of water while conducting temporary repairs and will remain on until complete cure time of Belzona products.

7.1.3.2. Approximate size of the cofferdam will be 36” wide by 72” tall.

7.2. Structural:

7.2.1. The contractor shall identify the cracked member(s) and/or degraded area(s) and provide a paper sketch of the area to be cropped and repaired using direction and recommendations called out in this work item. This sketch shall be submitted to the MSC REP and ABS for approval prior to work commencement. The area will be repaired to meet the original specifications as described in this work item unless a deviation is required and vetted through MSC REP and ABS.

7.2.2. The contractor shall mark the area to be cropped and repaired on the hull using direction and recommendations called out in this work item.

7.2.3. (CHECKPOINT) Wrap and seal all equipment including motors, pumps, hydraulic hoses and lines, sensors and electronic equipment to protect against water intrusion during water washing, blasting or cleaning solution.

7.2.4. Perform a HP water wash of the interior in inboard section using fresh water at 2,500 to 3,000 psi to remove dirt, mud, soluble salts and other foreign matter. Particular attention shall be given to the undersides of stiffeners, snipes, limber holes in longitudinals, crevices and areas of corrosion. The pitting identified areas in the corrosion inspection are to be treated extensively to eliminate all contamination in the pitting. Use of compressed air shall be used to blow out pitted areas of all loose debris. An appropriate solvent shall be used to clean the pockets and voids to the extent that provides the best possible surface to be coated.

7.2.4.1. Accomplish the requirements of SSPC-SP1, Solvent Cleaning, using a biodegradable detergent to remove residues of oil or grease that may be present.

7.2.4.2. (CHECKPOINT) Upon completion of all water washing, chloride testing shall be performed on random areas including the tank bottom and undersides of structural members. If contamination is found, additional tests shall be made as necessary to determine the extent of contamination and to prove the success of remediation. The maximum allowable contamination concentrations shall be less than 10 ug/cm2 of chloride contaminants as determined by field or laboratory analysis using reliable, reproducible test equipment.

7.2.4.3. (CHECKPOINT) Accomplish an inspection of the surfaces prior to blasting or bristle blast to determine if profile is required, in the presence of MSCREP and Ships Force. The surface appearance shall meet the requirements as defined in SSPC-SP10/NACE 2, Near White Metal Blast Cleaning. No paint shall be applied without approval of the MSCREP. Profile shall be determined using a Keane-Tator (or equal) Surface Profile Comparator. Testex (or equal) Replica Tape shall be used at a rate of one (1) reading per 1,000 SF for verification.

7.2.4.3.1. The contractor shall bid assuming a profile is not present and will require mechanical means to establish a new profile meeting the product data sheets of the Belzona products.

7.2.4.4. During media blasting activities/bristle blast, the use of dehumidification equipment is discretionary on the part of the contractor. However, it is expected that the entire space will be presented for inspection at one time. Piece-meal presentation will not be accepted. During the painting phase, dehumidification and forced air heating equipment shall be utilized. As a minimum, the equipment shall:

a) Maintain the temperature within the space at a minimum of 70 deg. F.

b) Effect a complete air change in the tank at least once every one-half (1/2) hour.

c) Maintain the relative humidity in the spaces within the limits set by the paint manufacturer for the coating being applied.

d) Maintain the Aluminum temperature at a minimum of 5 deg. F. above the dew point.

e) Ducting shall be run so as not to create hazards to personnel transiting the areas through which the ducting is run. Ducting shall further be maintained airtight and in good repair such that it does not contribute to contamination of the vessel’s interior or equipment with sandblast grit, dust or paint.

7.2.5. (CHECKPOINT) Prior to initiating abrasive blasting/bristle blasting, protect the vessel's equipment from damage caused by blasting abrasive, dust or paint. Measures to be taken include, but are not limited to, the following:

7.2.5.1. Appropriate measures shall be taken to ensure that the vessel's interior and its equipment are not subject to contamination from blasting media, dust or paint spray. The contractor shall be responsible for cleaning any contaminated ship outfit and furnishings as a result of missing or damaged protective coverings and ventilation ducts.

7.2.5.2. Prior to the start of productive work, protective covering shall be inspected and approved by the MSCREP. Deficiencies noted during this inspection shall be corrected and the MSCREP shall be afforded the opportunity to inspect and approve the corrective measures before work commences.

a) Protective covering shall be inspected at the start of each shift. Degraded protective covering shall be repaired prior to the restart of work.

b) Contamination of the vessel and its equipment shall be reported to the MSCREP verbally immediately upon its discovery, followed by a written report within four (4) hours of the verbal notification. The contractor shall be responsible for cleaning the contaminated equipment and showing that the contamination has not caused damage to same. Cost to repair equipment damaged by such contamination shall be borne by the contractor.

7.2.6. Prior to the start of abrasive blasting the blast media shall be tested to ensure that it is not contaminated with chlorides, as determined by field or laboratory analysis using reliable, reproducible test equipment.

a) Steel grit or shot media is not allowed for use on Aluminum or T-EPF for blasting.

7.2.7. Abrasive blast the interior of the spaces listed in section 3.0 including all structural members, and bulkheads to be coated in accordance with Surface Preparation Standard SSPC-SP10/NACE 2, Near White Metal Blast Cleaning. The blast profile achieved shall be angular in nature and within the range set by the manufacturer’s product data sheet for the coating system being applied. Profile shall be determined using a Keane-Tator (or equal) Surface Profile Comparator. Testex (or equal) Replica Tape shall be used at a rate of one (1) reading per 1,000 SF for verification. Replica Tape shall be mounted and identified as to location and included as part of the final paint report.

7.2.8. Upon completion of abrasive blasting/bristle blasting, remove all spent media, dust and dirt generated by this work item. Blown-down with dry, oil free air at a maximum pressure of 10 psi and/or vacuumed clean all internal tank surfaces.

7.2.9. (CHECKPOINT) Accomplish an inspection of the surfaces prepared in earlier in this section with the MSCREP and Ships Force. The surface appearance shall meet the requirements as defined in SSPC-SP10/NACE 2, Near White Metal Blast Cleaning. No paint shall be applied without approval of the MSCREP.

7.2.10. Contractor shall fabricate the following per reference 2.1.12:

7.2.10.1. 3 – TB 320min5_60x8 Detail 14-A

7.2.10.2. 3 – Bracket PL5 Detail 13-A

7.2.10.3. 10 – Shell Angle PL Detail PL5 12-A

7.2.11. Contractor shall apply a ¼ inch layer of Belzona 1111 between the Shell, FR web and TB. Fixing the plate to avoid welding to shell plating.

7.2.11.1. Application will be IAW with manufacturers product data sheet.

7.2.11.2. Contractor shall need to clean the material to remove all chlorides prior to application of Belzona product.

7.2.12. Contractor shall weld new angled plate to the FR web and tack to the TB web 1 inch on TB we and 5 inches on FR web.

7.2.13. Contractor shall apply two coats, 10 – 15 mils, of alternative color Belzona 1321 in areas of cracks, weeping and leaks to plug holes. External Temp Cofferdam will be used to dry the area for Belzona application. Application will be IAW with manufacturers product data sheet.

7.2.14. Contractor shall install new Fabricated TB and Brackets using reference 2.1.12 as guidance.

7.2.15. Contractor shall provide the following

7.2.15.1. Approved ABS GMAW Pulse welding procedure

7.2.15.2. Certified Nondestructive testing personnel

7.2.16. Contractor shall provide the service of a certified Marine Chemist to accomplish initial safe for hot and Competent Person to maintain compartments safe for hot work for the duration of performance period.

7.2.17. Contractor shall provide all equipment, tools, material and labor to accomplish repair structural damage. Only ABS approved materials shall be used in the execution of this work item.

7.2.18. Contractor shall remove and reinstall all interferences to accomplish this service order.

7.2.19. All work areas will broom cleaned daily and all tools properly stowed before the end of each shift.

7.2.20. Inserts shall include cut and insert plate or planking with a minimum of 75mm (3in) radius corners

7.2.21. Water tight integrity of the ships shell will be tested per ABS and MSC REP

7.3. Mechanical/Fluids: None

7.4. Electrical: None

7.5. Electronics: None

7.6. Preparation of Drawings:

7.6.1. The Contractor shall provide a sketch that clearly maps the areas for repair. Sketch will include cut dimensions, materials repaired and seams (existing and new). At a minimum the sketch will include all weld seams within 400mm of repair area.

7.6.2. A drawing redline shall be required to clearly map areas that were repaired if they differ from references 2.1. Sketch shall include cut dimensions, materials repaired and seams (existing and new). This shall be provided the MSC REP and ABS to approve any changes to the current repair plan.

7.7. Shipboard Inspection/testing:

7.7.1. Nondestructive testing (NDT) shall include dye penetrate (PT), ultrasonic inspection (UT), 5x visual inspection as well as visual inspection on the welds. Combinations are provided based on material state. If there is any doubt about the welds or materials further testing, inspection and repairs will be required. ALL Inspection and testing shall be completed in the presence of, and to the satisfaction of the MSC REP as well as the ABS surveyor.

7.7.2. For the MODERATELY SENSITIZED aluminum shell.

7.7.2.1. PT and UT shall be conducted on ALL shell plating seam welds.

7.7.2.2. PT shall be conducted on ALL welds in direct contact with exterior hull plating.

7.7.2.3. PT shall be conducted on all welds in direct contact with moderately sensitized material.

7.7.3. All other aluminum listed in this work item shall be considered to be NON-SENSITIZED:

7.7.3.1. NDT using 5X visual inspection over 100% of shell weld seam. NDT using PT on 100% weld corners and 20% on remaining weld seams.

7.7.3.2. The 20% structure PT locations shall be determined based on 5X visual inspection completed in the presence of ABS and MSC REP.

7.7.3.3. 5X visual weld inspection shall be completed on all primary structure that is not inspected by PT or UT. Exception is given for secondary structure that is not welded to hull perimeter and does not negatively affect design strength.

7.7.3.4. Secondary structure that is not welded to hull perimeter (i.e flat bar used to stiffen a frame panel or attachment of small electrical components) shall include NDT by visual inspection only (VT5X).

7.7.4. Contractor shall provide ABS and MSC REP with inspection checkpoints for fit-up, final welding and NDT as required by this specification and any regulatory specifications.

7.7.5. The contractor shall contact MSC REP and local surveyor prior to any work to ensure satisfaction is achieved during this installation. The ABS surveyor and MSC REP shall be present at fit-up, testing and prior to any final welds and post weld testing

7.7.6. The contractor shall furnish a hard copy or electronic report for each NDT inspection to the MSC REP and ABS Surveyor.

7.7.7. Provide a service report to the MSC Port Engineer in PDF format detailing all work accomplished and the results of all PT testing and inspections.

7.7.8. Shipboard Testing:

7.7.8.1. Tightness test using MSCGTR No. 3 as guidance. Testing per MSCREP and ABS surveyor.

7.7.8.2. The Contractor’s quality assurance plan shall be invoked for all aspects of this work item.

7.7.8.3. Additional testing as discussed in quality assurance section might be required based on test requirements and material conditions.

7.8. Painting: NONE

8. GENRAL REQUIREMNTS: none additional