0904_A_STERN_TUBE_SEAL_INSPECTION_(SW_SYS)_REV_-_(CSI).docx

USNS CARL BRASHEAR

(T-AKE 7)

STERN TUBE SEAL INSPECTION (SW SYSTEM) REV A

1.0 ABSTRACT:

1.1 This work item describes Stern Tube Seal inspection and overhaul. It applies to T-AKE Class Vessels with open salt water lubricated Stern Tube.

2.0 REFERENCES:

2.1 T/M T9243-AX-MMC-010, SHAFT SEAL, STERN TUBE, TYPE MD FOR USNS LEWIS AND CLARK (T-AKE 1) CLASS, INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS.

2.2 WARTSILA LIPS Drawing H74985-01 Rev(C), GA of 750 MOD 712 Type MD Seal, provided in Reference 2.1.

3.0 ITEM LOCATION/DESCRIPTION:

3.1 Location: Shaft Alley 5-79-0, FR 83

3.2 Quantity:

3.2.1 FWD SEAL; One (1) Each, Type MD Seal, Reference 2.1

3.3 Item Description/Manufacturer’s Data:

3.3.1 FWD SEAL; Wartsila Lips, for Water Lubricated Stern Tubes, Type MD Seal

3.3.2 Manufacture’s Data:

a. FWD SEAL Assy, For rigging purposes, approximate weight is 1384 lbs.

3.3.3 Bill of Materials (Contractor Furnished):

4.0 GOVERNMENT FURNISHED EQUIPMENT/MATERIAL/SERVICES:

4.1 Government Furnished Equipment/materials:

4.1.1 One (1) each Stern Tube Connecting Ring, PN W084837235.

4.1.2 All paint coating products.

4.2 Government Furnished Services: PPG Coating Representative.

5.0 NOTES

5.1 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 GTR’s.

5.2 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 001.

5.3 THIS SHIP CONTAINS HIGH VOLTAGE (HV) ELECTRICAL SYSTEMS. OBEY ALL POSTED AND VERBAL INSTRUCTIONS REGARDING SAFETY AND EXCLUSION FROM HIGH VOLTAGE AREAS. AT NO TIME APPROACH, WORK ON, OR ENTER A HIGH VOLTAGE AREA WITHOUT PROPER AUTHORIZATION.

5.4 THE T-AKE CLASS ELECTRICAL COLOR CODING DOES NOT FOLLOW CONSISTENT COLOR SCHEME. THE SHIP IS KNOWN TO HAVE CURRENT CARRYING CONDUCTORS COLORED GREEN, BLUE, BLACK, AND WHITE. ASSUME ALL ELECTRICAL CABLES ARE ENERGIZED UNTIL TESTED AND PROVEN OTHERWISE. TEST ALL ELECTRICAL CABLES TO ENSURE THEY ARE DE-ENERGIZED PRIOR TO WORKING ON THE ITEM.

5.5 This Work Item shall be worked in conjunction with Work Item 903 “Propeller Shaft and Stern Tube Inspection”. The ship shall be in Dry-Dock prior to performing this work item.

5.6 Contractor is responsible for rigging requirements including installation of additional pad-eyes, NDT testing and load testing.

6.0 QUALITY ASSURANCE REQUIREMENTS:

6.1 Shaft Seal disassembly and reassembly shall be performed in accordance with Manufacturer’s specifications.

7.0 STATEMENT OF WORK REQUIRED:

7.1 Isolate and tag out the system. Drain the affected piping and dispose of affected liquids in accordance with federal, state and local regulations.

7.2 Provide the services of a certified WARTSILA LIPS Field Technical representative to observe disassembly and reassembly of the Stern Tube Seal System. Inspection shall be accomplished of all mating sealing surfaces including shaft or liner surfaces upon removal of the propulsion shaft.

7.3 The Stern Tube Lubrication medium is a Salt Water Open flow system.

7.4 Temporarily remove interferences and re-install upon work completion.

7.5 FWD Stern Tube Shaft Seal Overhaul: Prior to rigging or removal, disconnect control air connections at the mounting ring assembly and inflatable seal connections, two (2) ea, located 180 degrees from each other on the mounting ring.

7.5.1 Close water supply valve to the stern tube and disconnect the supply piping from the mounting ring.

7.5.2 Drain and collect system fluids by opening the main drain on the mounting ring assembly.

7.5.3 In the presence of the Wartsila Lips Field Service Tech Rep, remove the Drive Clamp Ring Assembly. Take extreme care not to damage the mating sealing surface of the propulsion shaft.

7.5.4 Remove the Seat assembly and Face assembly. Mating sealing surfaces shall be inspected. Measure the Face Assembly nose length and document for historical purposes. Face Seal is a mandatory replacement item and shall NOT be reused.

7.5.5 When the main shaft is de-coupled, carefully remove the Mounting Ring Assembly, Main Clamp Ring Assembly, Carrier Assembly (with the Bellows Assembly) and the Stern Tube Connecting Ring. The Mounting Ring Assembly, Carrier Assembly, and Connecting Ring are not split components and must be removed when the propulsion shaft is de-coupled.

7.5.6 Jacking screws may be required to remove the Mounting Ring Assembly from the Stern Tube mating joint/bulkhead. The Mounting Ring has four (4) ea tapped through holes for fitting compression tooling. Jacking screws may be inserted to assist removal from the Stern Tube mating joint.

7.5.7 Transport the Stern Tube Seal Assembly from Ship to Shop for inspection of surfaces and overhaul.

7.5.8 Clean and inspect the mating sealing surface of the Stern Tube joint and bulkhead for defects. Defects such as high spots, burrs, etc. are not acceptable and shall be inspected by the Wartsila Tech Rep, and MSCREP. Provide Report of conditions found.

7.5.9 Take extreme care removing the inflatable seal. Remove the inflatable seal ring screws from the back of the mounting ring.

7.5.10 Remove the split support ring and remove the inflatable seal. If required, cut and remove the inflatable seal. Take extreme care not to gouge, ding, or burr the metal.

7.5.11 Transport Connecting Ring to paint facility for grit blast and painting.

7.5.12 All components of the Stern Tube Seal shall be cleaned and inspected for defects.

7.5.13 Upon removal of Stern Tube Assembly, ensure control air to Mounting ring assembly for inflatable seal and supply water piping fittings are satisfactory for reuse.

7.5.14 Stern Tube Seal shall be overhauled in Machine Shop in a clean environment.

7.5.15 Wartsila Lips Field Service Tech Rep shall be present to observe and provide guidance during the Stern Tube Shaft Seal inspection and overhaul process.

7.5.16 All components shall be cleaned and inspect prior to reassembly.

7.5.17 Clean Mounting Ring Assembly air connections and water flush connections. Ensure threads are clean and free of debris.

7.5.18 Using reference 2.0 as guidance, install new inflatable seal.

7.5.19 Reassemble Mounting Ring Assembly with new inflatable seal and adaptor ring. Install the Carrier Assembly with new Bellows Assembly in accordance with reference 2.1.

7.5.20 Seat Overhaul and Refurbishment:

a. Take extreme care not to damage the “O-Cord” grooves. Cover the grooves prior to machining.

b. Machine the running face to remove the wear track. Follow the procedure identified in reference 2.1, paragraph 12.7.1.

i. Seat Assembly shall meet criteria identified in reference 2.1 for flatness and surface finish.

c. Upon completion, notify ABS, and MSCREP to witness completed Seat machining in shop.

d. Reassemble FWD Seal in accordance with references 2.1 and 2.2.

7.6 The MSC Rep and Wartsila Representative will determine if original or replacement Connecting Ring shall be used. Contractor shall blast either the replacement or refurbished connecting ring to near white metal finish, NACE 2 SSP-10 surface roughness and blast profile of 75 RZ micron (3-4 mils) minimum.

7.6.1 Apply three coats Amercoat 240 to the Connecting Ring as directed by the Wartsila Representative.

7.6.2 Some areas of the Connecting Ring “do not require painting. The Connecting Ring has machined sealing surfaces and areas that will be coated with Belzona 5811 after mounting the Connecting Ring to the Stern Tube. Contractor shall paint the Connecting Ring “only” in areas designated by the Wartsila Representative.

7.7 Installation of Stern Tube Seal Assembly:

7.7.1 Transport connecting ring from shop to ship.

7.7.2 Install Connecting Ring to the stern tube flange with new Contractor Furnished gasket.

7.7.3 Connecting Ring and FWD end of Stern Tube shall be coated with GFM PPG Coating Product as directed by the Wartsila Representative and allowed to fully cure prior to installation of Stern Tube Seal Assembly. Contractor is directed to reference Work Item 0903 Propeller Shaft and Stern Tube Inspection for Coating application.

7.7.4 Transport the partial assembly of the Stern Tube Seal from Shop to Ship.

7.7.5 Install new gasket to the Stern Tube Joint/Bulkhead.

7.7.6 Carefully rig the partial assembly (Mounting Ring, Bellows, and Carrier Assemblies) on the propulsion shaft. Install partial assembly to the Stern Tube mating joint/bulkhead with gasket in place.

7.7.7 Upon complete installation of the propulsion shaft, set the distance between the Carrier Assembly and the Mounting Ring Assembly in accordance with reference 2.2.

7.7.8 Install the Face Sealing Strip in Accordance with reference 2.1.

7.7.9 Install the new face Seal (Split Seal) in accordance with reference 2.1. Lightly grease the face seal taking extreme care not to damage the mating sealing surface or leakage could occur upon final assembly. Lightly grease the face seal taking extreme care not to damage the mating sealing surface or leakage could occur upon final assembly.

7.7.10 No obvious steps in the Face Seal shall be present.

7.7.11 Compress the seal in accordance with reference 2.1 using the compression tools. Refer to paragraph 12.8.7 for procedure.

7.7.12 Ensure the Propulsion shaft is clean and free of obvious dirt and debris.

7.7.13 While maintaining the set dimension between the Mounting Ring and Carrier Assembly, install the Seat Assembly. Apply grease to the “O” Cord grooves.

7.7.14 Install the Drive Clamp Ring Assembly in accordance with reference 2.1.

7.7.15 Install inflatable seal supply air and stern tube supply water piping to the mounting ring assembly.

7.8 Stern Tube Seal Alignment:

7.8.1 Wartsila Lips Field Service Tech Rep shall witness alignment procedure.

7.8.2 Align the Stern Tube Shaft Seal by rotating the shaft with the jacking gear in accordance reference 2.1. Dial indicators shall be used to set the alignment to +/- 0.002”.

7.8.3 Document alignment data.

7.8.4 Notify ABS and the MSCREP to witness alignment.

7.9 Perform inflatable seal test to ensure a satisfactory seal. Follow Steps identified in reference 2.1, paragraph 7.2.2.

7.9.1 Verify Shaft Diameter in-way of the Stern Tube Shaft Seal is 648mm.

7.9.2 The inflatable air test is 5 Bar with an allowable leakage of 1 Bar or less in 30 minutes.

7.9.3 Notify ABS and MSCREP to witness tests.

7.9.4 Hydrostatic Seal Test:

a. FWD Seal:

i. Activate the inflatable seal to 0.3 Bar above the seal water test pressure.

ii. Perform the required Hydrostatic Test in accordance with references 2.1 and 2.2.

iii. Notify ABS, Chief Engineer, and MSCREP to witness Hydrostatic test.

b. AFT Seal:

i. Hydrostatic testing of the Aft Seal shall be accomplished in the Dry Dock after the Aft Seal has been assembled and mounted to the Stern Tube Face (Mounting Ring). See Work Item 0903 “Propeller Shaft and Stern Tube Inspection With Aft Seal”.

7.10 Painting:

7.10.1 Paint removed to accomplish the Stern Tube Seal removal and reinstallation shall be repainted to match surrounding surfaces.

7.11 Manufacturer’s Representative:

7.11.1 Provide the services of a certified Wartsila Lips Field Technical representative to observe disassembly and reassembly of the Stern Tube Seal. Inspection shall be accomplished of all mating sealing surfaces including shaft or liner surfaces upon removal of the propulsion shaft.

7.11.2 The Wartsila Lips Field Technical representative shall oversee alignment, air tests, hydrostatic tests, perform Dock and Sea Trials to ensure satisfactory installation and operation.

7.11.3 Recommended Source:

Wartsila Defense, Inc.

3617 Koppens Way Chesapeake, VA 23323 Scott Miller Office: (757)966-5420 Fax: (757)558-4831 Cell: (757)927-4422

8.0 GENERAL REQUIREMENTS: None additional.

904-1