SN 29891 Rotor repair SOW dtd 21Mar2024.pdf

21 March 2024

NSN 2S 2010-01-470-6594

Repair Statement of Work (SOW) SSN 21 Class Rotor

SN 29891

The following references apply:

(a) Technical Data Package & CDRL's A004, A005, A006, A007, A008, A009

(b) NAVSEA 245-6676151 Rev G (C)

(c) NAVSEA S9245-AZ-TSM-010/PROP (C)

(d) NAVSEA S9245-A4-TSM-010

(e) NAVSEA 245-8181025 Rev A, SEAWOLF Class Propulsor Axis Vertical Lifting

Details & Transporter Attachment Procedure

The following notes and miscellaneous requirements apply.

1. All inspections and repairs shall be performed in accordance with references (a) through (e), as applicable, except as noted herein. In the event of a conflict between the references cited and this statement of work, the statement of work shall take precedence.

2. The facility must have personnel that have CONFIDENTIAL clearance and have successfully completed the NAVSEA Ducted Propulsor Visual Inspection Course.

3. CONFIDENTIAL inspection forms shall be submitted as a separate inspection report.

4. The vendor shall meet all applicable coatings qualification requirements of reference (d), including Society for Protective Coatings SSPC-QP3 qualification or NAVSEA approved equivalent. If the vendor is not qualified to SSPC-QP3 or by NAVSEA, they have the option to identify a qualified subcontractor to perform blasting and painting operations. All personnel performing abrasive blasting shall have CONFIDENTIAL clearance and shall be certified in accordance with SSPC C-7, Abrasive Blasting. All personnel performing coatings application shall have CONFIDENTIAL clearance and shall be certified in accordance with C-12, Spray Application Certification, or SSPC C-14, Marine Plural Component Program.

5. Stacking of SSN 21 class rotors is not authorized.

6. The rotor does not have side lifting points and a turnover fixture or J-bar is required for flipping. The means for flipping is the responsibility of the vendor and there is no GFE turning fixture designated for refurbishment work. The required sling length is a minimum of 15 feet for a straight lift, but a spreader bar is an acceptable alternative to maintain minimum 81 degree sling angle in accordance with Sheet 004-12 of reference (e).

ITEM 0002: Pre-Repair.

1. Following cleaning, perform a visual technical inspection (VTI) on all painted surfaces (both internal and external) in accordance with references (b) and (c). The VTI shall not include trailing edge high stress region, tap testing, or any liquid penetrant inspections.

2. Remove paint layers, anti-fouling (AF) and anti-corrosion (AC), from all surfaces, including hub bore, by abrasive blasting or by hand sanding as necessary except for surfaces in way of CUSP and trailing edge high stress region, which shall still maintain 125 RMS final surface finish. Blast media shall be in accordance with reference (d).

3. Perform a baseline inspection of the CUSP areas using laser scanning inspection process to generate a dense point cloud inspection data record. The point cloud density shall be no less than 300 points per square inch. Apply spray developer to all surfaces prior to scanning inspection surface. The extent of the local region for inspection and best-fit analysis shall be the entire cusp area. The best-fit CUSP regions are defined as the pressure face with wrap and suction face with wrap. The pre-repair data shall be provided to Propulsor Technology Inc. (PTI) at the address provided below for Navy pre-repair evaluation (vendor is not responsible for the pre-repair evaluation of the collected data). The Navy evaluation will be provided to the vendor within 21 days of receipt of the data. A copy of the Navy evaluation shall be included as part of the vendor’s dimensional report.

Propulsor Technology Inc.

80 Emerson Lane Suite 1302 Bridgeville, PA 15017-3472 Attn: Jim Machin, 412-914-1100

4. Perform dye penetrant aided visual inspection of trailing edge high stress region in accordance with references (b) and (c). During dye penetrant inspection of trailing edge high stress region, record all linear bleed out indications 1/16" or larger and record all round bleed out indications greater than 1/8".

5. Perform ultrasonic testing inspections of blade 3C welds and MAF design welds in accordance with reference (c).

6. Perform a pre-repair dye penetrant aided visual technical inspection (VTI) including tap test in accordance with references (a), (b), and (c) as applicable.

7. Remove previously installed bushings (hub flange sleeves) using hydraulic jacks.

8. Perform System 21 Class 2 thread inspection on forward and aft hub face threaded holes used for lifting and handling (11 total). If the threaded holes fail the System 21 thread inspection, perform System 22 inspection.

INSPECTION AND ACCEPTANCE: Inspection and acceptance of Item 0002 shall be in accordance with reference (a).

ITEM 0004AA: Balance Weight and Bushing Material

1. Provide the following SSN 21 Class balance weight attachment hardware in accordance with reference (b): Provide one rotor set of each item in accordance with reference (b). Procure additional material to accomplish certification testing and retain a permanent heat sample record.

a. Drawing item 46, 0.625 x 2.25" L balance weight attachment hex cap screw.

Estimated quantity required 36 each.

b. Drawing item 47, 0.625 x 3.5L balance weight attachment hex cap screw.

Estimated quantity required 24 each.

c. Procure and install one rotor set of item 31, bushings, (12 each) in accordance with reference (b). Remove previously installed bushings and replace with item 31 procured above.

ESTIMATED COST: Not separately priced

ITEM 0004AB: Repair and Inspection of Rotor

1. Repair rotor surface defects in accordance with acceptance criteria defined in references (b) and (c). Perform liquid penetrant (PT) aided visual inspection at the excavated areas prior to welding. Perform post repair inspections in accordance with reference (c) for all repaired areas. Note that special requirements apply for the TE high stress area.

2. Out of tolerance CUSP defects shall be repaired by fairing and welding as required.

The repaired areas shall be inspected using laser scanning inspection process to generate inspection data and the results shall be compared to baseline inspection data. The point cloud density shall be no less than 300 points per square inch. Apply spray developer to all surfaces prior to scanning inspection. The extent of the local region for inspection and best-fit analysis shall be the entire cusp area. Fairing rod, edge gauges, nested tip gauges, or any other templates may be used for repair grinding and blending. The best-fit CUSP regions are defined as the pressure face with wrap and suction face with wrap. The post-repair data shall be evaluated by the vendor using the SSN 21 Class Rotor CUSP Analysis Program (provided as GFP). A copy of the post-repair data shall be provided to PTI for information in the event that Navy technical support is required. A copy of the evaluation shall be included as part of the dimensional vendor report. Provide advanced copy of the evaluation to NSWCPD Code 426 following post-repair inspections. Need for additional fairing will be determined by NSWCPD Code 426 from analysis of results.

All standard leading edge fairness requirements (no nicks, flats, gouges, etc) shall be maintained.

3. Fill voids as necessary to meet repair tolerance per reference (c). Void filler material and plugs for fill and vent voids shall be in accordance with reference (c). CD45 filler material shall be provided as GFP.

4. Re-stamp data and TDC markings as required in accordance with reference (b) and add the following information, REP & BAL, (VENDOR) DATE (MM/YY).

5. As required, repair threaded holes in accordance with reference (c).

6. Replace all fastener lock wire in the rotor hub.

7. Perform visual inspection in accordance with reference (c) of the rotor external surfaces prior to paint re-application, as applicable. Include post repair void tap test inspection results. Additional UT and PT inspections not required once performed at individual repaired areas. Provide advanced copy of VTI to NSWCPD Code 426 for acceptance prior to blast and paint application.

8. All surface preparation and paint application shall be performed in accordance with reference (d). As required, Phillybond TA-30 shall be applied to porosity and joint seams after the first coat of paint has cured. The TA-30 shall be faired in to match surrounding surface and reapplied, if required, to ensure fairness. Note that Phillybond TA-30 may also be used as an alternative grooming material to PR-944, which is specified in reference (d). These repairs shall be roughened with 120 grit emery paper before application of the second coat of paint. All coatings inspections shall be performed by a Level 3 NACE Certified Coatings Inspector in accordance with reference (d), Appendix A. Upon completion, the NACE certified inspector shall provide written verification of successful coatings application to the vendor and NSWCPD Code 426.

a. The CUSP and trailing edge high stress area as outlined in reference (d) shall be left unpainted. The specified unpainted CUSP area shall be masked prior to the initiation of work and remain masked at all times throughout preparation and painting operations. After paint curing, the area around the perimeter of the unpainted area shall be hand sanded to make a smooth transition as defined in Appendix A of reference (d).

9. Following complete paint application, perform final VTI of all painted surfaces to ensure they conform to the paint requirements specified within.

10. Balance the rotor in accordance with reference (c) following paint preservation application. Note that a custom SSN 21 Class Rotor Balance Plate (provided as GFP) is required to align with the forward flange face alignment pin holes. When landing the rotor on the balance plate pins, the rotor shall be shifted on the pins toward the bottom dead center position to simulate ship installation.

11. Provide lifting and handling support for Penn State ARL acoustic testing for approximately five (5) days. The testing shall be performed in air, and the test tank is not required. No funding is required for Penn State ARL.

11. The following actions apply to the rotor accessory plugs:

a. The four (4) forward flange accessory plugs, item 43 of reference (b), shall be blasted, primed, installed, and then painted with paint system 1 per reference

(c) prior to shipment.

b. The aft flange accessory plugs (remaining item 43’s) shall be blasted and primed in accordance with reference (b) prior to packaging for shipment.

c. Provide a shipping container for rotor accessories in accordance with reference (c). Shipping direction will be provided via separate correspondence.

11. Package and prepare the rotor for shipment in accordance with reference (c). Note that strippable coating shall not be applied. The AC/AF preservation paint must be cured prior to packaging in accordance with the applicable dry to touch and dry to handle times.

The cured paint film shall resist a thumb deformation test (similar to ASTM D1640, paragraph 7.7.1) before packaging can begin. One layer of 0.187 inch thick cloth reinforced rubber shall be used under MAF edge guards.

The following GFP shall be used for ITEM 0004AB:

1. SSN 21 Class Rotor CUSP Analysis Program

2. Rotor Shipping Fixture Assembly S/N N0176, NICN LLTRL5541

3. SSN 21 Class Rotor Balance Plate

4. CD-45 Filler Material

ESTIMATED COST: TBD

SHIPPING:

The rotor shall be shipped to the following address:

DoDAAC: N4523A Puget Sound Naval Shipyard & IMF 1400 Farragut Ave Bremerton, WA 98314 POC: Kenny Benjamin (360-627-6831 / kenneth.l.benjamin@navy.mil)

INSPECTION AND ACCEPTANCE: Inspection and acceptance of Item 0004 shall be in accordance with the attached CDRL’s by 31 JULY 2025.

ITEM 0006: Data

Data for Item 0002 shall consist of visual technical and dimensional inspection results in accordance with the attached CDRL’s and as specified herein. (CDRLs A004, A005, A006, A007, A0008, and A009 apply).

1. PROPVAL LEICA scan report

2. Pre-repair VTI including dye penetrant and ultrasonic inspections

3. Threaded hole dimensional inspection

Data for Item 0004 shall consist of visual technical and dimensional inspection results in accordance with the attached CDRL’s and as specified herein. (CDRLs A004, A005, A006, A007, A0008, and A009 apply).

1. Post repair PROPVAL LEICA Scan Report, if required

2. Post repair UT inspection, if required

3. Pre-Blast VTI

4. Post Paint VTI - Rotor final condition and condition of accessories (painted and/or installed)

5. Coatings application Certificate of Compliance

6. Accessory cert package

7. Balance inspection forms

8. New bushing report with material certs and dimensions

NAVSEA inspection form 9245/9 shall be utilized in lieu of NAVSEA form 9245/3.

Classified inspection data shall be submitted as a separate report. Submit inspection reports to NSWCPD Code 426 and copy of the report transmittal letter to NAVSUP-WSS Code N97121. Allow 15 days for government review and approval.

ESTIMATED COST: Not separately priced

ITEM 0006: Data