Sledge Strain Gage SOW.docx

Statement of Work Sledge Propulsion Shafting, Strain Gage Alignment

PR# 2123403Y6172M96001

POC: Carl, Weiland Phone: 410-320-9154

SCOPE

Contractor to perform strain gage alignment inspection aboard USCGC Sledge in Baltimore MD on or around 11/08/22. The intent of the strain gauge alignment check is to document the state of the existing alignment of the propulsion shafting, to ensure existing alignment is correct and to collect baseline data.

The anticipated scenario to complete the required alignment measurements is as follows:

Pre-dry-dock inspection. The Contractor shall submit a written report of results with the following information to the COR within 48 hours after alignment check:

All inboard bearing reactions, bearing offsets, bearing influence numbers, allowable bearing load, bearing clearances, etc A description of the alignment procedures used to obtain the bearing loads Strain gage locations Bearing locations and reactions in shaft modeling Detail dimensions and configuration of the shaft model All mathematics values used in the shaft model such as material properties, spring constant, thermal growth effects, bearing offsets, all concentrated weights, etc All assumptions applied in the shaft model All constant values used in the shaft model Any indication of misalignment Bearing reactions at the calculated optimum shaft alignment condition Any recommended corrective procedures. The recommended corrective procedures shall include, but not be limited to:

New bearing off-sets to achieve an optimum shaft alignment New bearing off-sets to achieve a satisfactory (acceptable) shaft alignment Other alternative to achieve an optimum shaft alignment Detailed procedures to achieve shaft alignment

Dry-docking inspection. After dry-docking the vessel and before performing any hot work and/or structural modifications, the Contractor shall conduct a strain gage alignment inspection to determine all bearing reactions (five bearings per shaft) as specified in 3.3 through 3.3.2. Provide additional strain gauges, temporary wiring, and set-up on the shaft outboard as required for the three outboard bearing measurements. Submit a CFR with information as specified in 3.3.2 within 48 hours after alignment check. Before re-floating alignment inspection. After all the hot work and/or structural modifications have been completed, and before re-floating the vessel, the Contractor shall conduct a strain gage alignment inspection of shaft alignment as specified in 3.3.3 and compare the results with dry-docking inspection. Submit a written report with any recommended further action to the COR within 48 hours after alignment check.

Post-dry-dock inspection. The Contractor shall conduct post-dry-dock inspection of shaft alignment per paragraph 3.2 through 3.3.2 for all the inboard and outboard bearings (total five bearings per shaft). Use similar set-up as the dry-docking inspection. Submit a CFR similar as the pre-dry-docking report including the additional information of the three outboard bearings of each shaft, within 24 hours after taking the strain gauge readings. The inspection report shall compare the findings of the inboard bearings with the pre-dry-dock conditions and provide analysis, comments and recommendations.

Alignment drawing. The Contractor shall provide an alignment drawing clearly showing all components including reduction gear and all bearings, a table of calculated influence numbers and reactions of each shaft bearing and reduction gear bearing at afloat and dry-docking conditions, and calculated optimum bearing reactions.

The Contractor shall ensure all bearing compression and clearances, bearing offsets relative to the bore sight reference line, General Notes, and related shaft reference drawings shall also be included on the drawing. In addition, The Contractor shall provide a table of calculated bearing wear down analysis.

The Contractor shall submit a preliminary drawing to COR for approval within seven (7) calendar days after final alignment has been determined. After revising the drawing based on the comments of COR, submit two (2) sets of the final drawing to COR within 14 calendar days upon completion of work. Submit one set of inspection report and final drawing to the COR (See 4.1 (Result submittals)).

Ship / Yard Assistance Required

Provide access to the shafting and remove interferences as required Provide ship or yard personnel to rotate the shaft as required Provide electrical power 115 VAC as required