0906_A_MainPropShafting and CPP repairs.doc

USNS SIOUX

(T-ATF 171)

DRYDOCKING

CONTRACT NO. N40442-10-R-XXXX

ITEM NO. 0906

CATEGORY "A"

7/27/2010 Main Propulsion Shafting / CPP Repair

/Collins/GT

1.0

ABSTRACT

1.1 The item describes the requirement to disassemble, inspect, and reassemble the shafting systems (Port & Starboard) for inspection of components.

2.0

REFERENCE/ENCLOSURES

2.1 References:

2.1.1 NAVSEA Technical Manual No. S9252-AG-MMO-010 (Available on ship during bidder’s survey).

2.1.2 MSC Drawing No. T-ATF-203-4842550, Shafting Arrangement (Available on ship during bidder’s survey).

2.1.3 MSC Drawing No. T-ATF-203-4842551, Stern Tube ARR. & Dets. (Available on ship during bidder’s survey).

2.1.4 MSC Drawing No. T-ATF-250-4842566, Rudder & Propeller Lifting Gear Arrangement. (Available on ship during bidder’s survey).

3.0

ITEM LOCATION/DESCRIPTION

3.1 Stern of the vessel port and starboard.

3.2 C.P. Propeller Systems. Port & Starboard

3.3 C.P. Propeller System

MFR: Propulsion Systems Inc.

609 NW 45 st., Seattle, WA, 98107

Phone 206-789-0944

3.4 Stern tube oil seal box:

3.4.1 MFR: John Crane/Waukeshau Bearing Co.

TYPE: Mark II, Type 330, John Crane

4.0

GOVERNMENT FURNISHED MATERIAL/EQUIPMENT/SERVICE:

4.1 All oil to be GFM.

4.2 PSI Technical representative (CPP) , Coastal Tech Rep.(Stern Tube Seal Rep.)

(a) Propeller Blade Seal Kit

(c) Stern Tube Seals

(b) Pressure Shrunk Coupling Seal Kit

(c ) Hub oil

4.3 Waukeshau shaft seal bearing kit.

5.0

NOTES:

5.1 The rudders are temporarily removed and reinstalled in a separate work item in this work package.

5.2 The contractor and all subcontractors regardless of tier shall 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 including but not limited to GTRs 1 through 7, 22, 23, and 29.

5.3 The contractor and all subcontractors regardless of tier are advised to review other work items under this contract. Many of the definitions relating to performance of this work item are found in Work Item 001.

6.0 QUALITY ASSURANCE REQUIREMENTS: None additional.

7.0 STATEMENT OF WORK REQUIRED:

7.1 Submit a unit price to accomplish the following work item. Work specified herein shall be accomplished under the direct supervision of the manufacturer’s service representative.

7.2 Maintain cleanliness of the job site to ensure components are not contaminated.

7.2.1 Construct temporary enclosures around the propeller assemblies after cleaning of components but prior to disassembly.

7.2.2 All openings in shafting, piping, bearings, stern tubes and other components subject to contamination shall be closed immediately using gasketed blanks.

7.2.3 No contamination generating operations shall be performed in the area of the job site while system components are exposed.

7.2.4 All machined or finished surfaces subject to damage shall be masked and/or wrapped.

7.3 The following work statement outlines the work required. A detailed description is provided in Reference 2.1.1.

7.4 Prior to the removal of any shafting components, take and record shaft wear down readings as identified in Work Item 0907. Upon reinstallation of all shafting components take and record another set of wear down readings.

7.5 Submit an “as found” condition report which compares “as found” conditions to original design dimensions.

7.6 Secure the servo oil system and tag-out pump motor controllers.

7.6.1 Drain and dispose of the oil from the propeller hubs, shafts, and stern tubes.

7.6.2 Allow propeller hubs to remain stationary for a sufficient time to allow water to settle out of the oil. Collect a sample from the very first portion of oil drained from each hub and have the samples analyzed for water and trace elements.

7.6.3 Take four additional samples as directed by the manufacturer’s representative and have them analyzed by an established laboratory. The laboratory is to test the samples for water and trace elements and submit three copies of the “as found” condition report to the MSCREP.

7.7 Disconnect the SKF coupling on each shaft. Furnish all equipment including hydraulic “enerpac” pumps for performing all work.

7.7.1 Inspect couplings and check fit of couplings to shafts via blueing. The contractor is to include in the price for this work item all material and labor required for four (4) in place blueings for each .

7.7.2 The contractor is to include in the price for this work item all material and labor required for the fabrication and installation of three (6) new fitted bolts on each SKF coupling. Installation shall require in-place reaming of the coupling/line shaft bolt holes to accept new oversized fitted bolts. If replacement bolts are determined not to be required, these costs will be reimbursed to the Government via a credit change order.

7.8 Temporarily remove the rope guards for each shaft. Reinstall with proper clearance upon completion of all work.

7.9 Loosen the “Waukesha” seals.

7.10 Remove four (4) stern tube access/closure plates for inspection of seals and bearings. PORT & STARBOARD SHAFTS.

Prior to reinstallation of shafts, fit and install doors and conduct vacuum box test to prove “NO LEAK”.

After reinstallation of shafts, reinstall closure plates using monel hex cap screws as per drawing and sealed all around using 3M 5200, quickset sealant. Ensure plates are reinstalled and bolted in place with the proper gasketing and using the bolting sequence described in the drawing.

7.10.1 Unbolt the oil tubes and remove the tail shafts.

7.10.2 Support the shaft at all times to ensure no strain or distortion is applied.

7.10.3 Weld padeyes to the hull as required for the removal and reinstallation of components. Padeyes shall be sized to accommodate anticipated loads. All padeyes, whether existing or installed by the contractor, shall be tested to 1-1/2 times the anticipated load.

NOTE: For bid purposes: Propulsion Systems Inc. has a procedure which allows for the shaft support without the requirement of welding pad eyes on the hull with adjacent fuel tanks, fuel does not have to be removed from the tanks to perform the shaft removal and re-insertion.

7.11 Disconnect the shaft at the coupling, pull the shaft and temporarily remove the propeller assembly(hubs and blades) and shaft to the shop to change blade seals Match mark fitted coupling bolts before removing. Use reference 2.1.4.

7.11.1 Temporarily remove keeper rods from blade bolts and remove bolts and blades.

7.11.2 Remove the old propeller blade seal rings, clean the oil seal grove, the outer bearing ring, and the crank disc surface.

7.11.3 Change blade seals with new GFM blade seals.

7.11.4 Clean and inspect oil tubes.

7.11.5 Change “O” rings (GFM) on the hub forward flange cover.

7.11.6 After all components have been inspected by the MSC Port Engineer, USCG, and ABS, reinstall the hub assemblies onto the propeller shaft with new oil seal “O” rings. Prior to installing the hubs, the oil tubes and interior of the stern tubes shall be flushed with oil, approximately fifty (50) gallons per stern tube will be required. All oil is GFM, Any Flushing equipment shall be flushed with this oil prior to use.

7.11.7 Flush the hub assembly system with new hydraulic oil. 50 gallons per shaft.

7.11.8 Clean the palm surfaces of the blade and the dowel pins, making certain there are no nicks, dents, or other damage to prevent proper seating against the crank disk or the other outer bearing ring. Clean out blade holes and counterbores, especially the counterbore seat to ensure proper blade seating.

7.11.9 Polish the port and starboard propeller blades and CPP hubs to a Rupert “B” finish. Dye check the blade palms and the blade trailing edges in the presence of ABS surveyor, and the MSC Port Engineer.

7.11.10 Apply a light coat of Silastic 723 RTV at the bottom of the blade seal groove. Install new blade seals.

7.11.11 Thoroughly clean blade bolts and inspect threads for damage. Accomplish a liquid dye penetrant inspection of the 64 blade bolts in the presence of the ABS surveyor and Port Engineer.

NOTE

IF THERE IS ANY DAMAGE TO THREADS, CHASE THREADS, COAT BOLT THREADS AND BOTH SIDES OF SEAL WASHER WITH ANTISEIZE COMPOUND, AND ENGAGE BOLT IN UPPERMOST HOLE. THE BOLT IS TO BE THREADED IN UNTIL IT BOTTOMS IN THE BLADE COUNTERBORE USING HAND FORCE ONLY. IF THE BOLT DOES NOT THREAD IN ALL THE WAY, REMOVE BOLT AND CHASE THREADS IN CRANK DISK WITH 1-1/2”-8 TAP. COAT TAP WITH GREASE TO PREVENT CHIPS FROM FALLING INTO THE HUB.

7.11.12 Bolt blades onto hubs using new bolt seal washers. After all bolts on the blade are seated by hand, tighten bolts with socket wrench and remove tackle. MSCREP to witness.

ALL BOLTS SHALL BE TORQUED USING THE OPPOSITE BOTH TIGHTENING SEQUENCE BOTH AT HAND TIGHTENING AND TORQUING. CONTRACTOR SHALL PERFORM ALL WORK USING THE STATED BOLT TIGHTENING SEQUENCE ON ALL C.P. BLADES

7.11.13 Remove the forward and aft “John Crane/Waukesha” oil seal boxes and transport to shop. Completely dismantle the oil seal boxes and remove the old seals. Clean all seal components and ensure there are no nicks, dents, or other damage to prevent proper seating of oil seals and glands. If required, machine the oil seals sleeves to smooth surface as recommended by manufacturer and use oversized seals.

7.11.14 After the oil seal box is inspected by the manufacturer’s representative, reassemble the unit as original with new oil seal ring kits and convey to ship and reinstall with new gaskets. (2) stern tube bearings and (2) “John Crane/Waukesha” stern tube oil seal boxes to be dealt with.

7.12 Perform magnaflux test on the propeller flanges and coupling bolts in accordance with ABS requirements. All the testing shall be performed in the presence of the ABS Surveyor, USCG, and MSC Port Engineer. A total of four (4) flanges two (2) on each side for the main propulsion shaft systems are to be dealt with.

7.13 Drain the one line shaft bearing sumps. Remove the top covers and top half bearings. Rig and support the shafts and roll out the lower half rings. Measure and inspect bearings in the presence of ABS. Record and submit readings to the MSC Port Engineer. When completed and directed by MSC Port Engineer, reinstall the line shafts.

7.13.1 While shafts are removed, take micrometer readings on the shaft journals and stern tube bearings. Two readings ninety (90) degrees apart at each location are to be taken. Submit an “as found” condition report.

7.13.2 Hand polish the bearings and journals to remove minor scratches.

7.13.3 Refill the line shaft bearing sumps with new GFM oil.

7.14 Reinstall the stern tube shafts under the supervision of the manufacturer’s representatives.

7.15 Upon completion of all related work, reinstall propellers.

7.16 Conduct a flush of the hydraulic system after repair. Oil will be GFM if required.

7.16.1 Open and clean the stern tube and hub oil sumps and head tanks.. The capacity of the two (2) sumps is approximately 750 gallons each and the four (4) head tanks is approximately 55 gallons each. The head tanks are located at the overhead of the engine room and contain level switches in the access cover. Care shall be taken to ensure the switches and cables are not damaged. Connect the servo lines, exhaust lines, control lines, PMC lines and hub lines through a 10 micron filter and a magnetic filters and discharge into the system drain line. Tap all piping every few inches. Flush for a minimum of 12 hours to the satisfaction of the MSCREP if required by Tech. Rep.

7.17 After all work is completed, refill the C.P. hydraulic systems as necessary for proper operating levels using the retained flushing oil.

7.18 Close the hub oil head tank valves, rotate the hub so that one of the hub pipe plugs is on top dead center (TDC). Remove the plug so that air can vent out.

7.19 With the hub oil relief valve set for 30 PSI, start the hub oil pump. When oil flows from the hub vent plug, insert the plug and stake it. Open the hub oil head tank fill valve and fill the head tank until it overflows.

7.20 Set the main pump relief for its minimum setting, (approximately 200 PSI), then start the motor driven servo pump. Pitch the system manually to bottom astern then bottom ahead, repeat this several times to expel all the air in the oil tubes and servomotor cylinder. With the system bottom ahead, set the relief valve to 750 PSI.

7.21 Keep operating oil pressure on line for 24 hours and check for leaks.

7.22 Remove staging and keep propeller areas clear. Ship’s force will turn the propellers with the main engine and check for leaks.

7.23 If no leaks are apparent as directed by MSC Port Engineer, weld the blade bolt keepers to the blade bolt heads. The new bolt keepers are to be fabricated by ½” diameter stainless steel bars. A ¼” tack weld 3/8” long, on each bolt head, on the keeper rod and away from the bolt head flats, is sufficient.

7.23.1 The welding ground wire is to be attached to the bolt at which the keeper is being welded to prevent arcing through the hub.

7.24 All oil and material is to be disposed of in compliance with all U.S. Government, State, and Local anti-pollution and public health regulations.

7.25 Manufacturer’s Representative:

7.25.1 Coastal Seal is a know reputable source and will be provided by MSC.

Phone : 630-267-7431

8.0 GENERAL REQUIREMENTS: None additional.

ASA9APACHE_20090406

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