SOW_TD-21_Structural_Modifications_for_Steerng_Upgrade.pdf

Tugboat TD-21 Steering Modification Structural Upgrade of Deck April2018

Purpose:

In order to upgrade the steering system on TD-21, a tugboat assigned to the James River

Reserve Fleet, from the currently installed wire rope steering, to a hydraulic steering package, two new hydraulic steering cylinders are to be installed on the deck forward of the rudder stock. These cylinders require a new foundation and associated backing structure to effectively transmit loading from hydraulic cylinders into existing ship’s structure. This requirement is for performing the required structural upgrades and does not include installation of any steering components. The work may be performed at the James River Reserve Fleet Pier at Fort Eustis

Va. or at the contractor’s facility. If the contractor prefers to accomplish the work at their facility, MARAD will deliver the TD-21 to the contractor’s facility, which shall be located within

30 nautical miles of the James River Reserve Fleet.

References:

1. S/C sketch 02 (Appendix 3)

2. S/C sketch 03 (Appendix 4)

3. S/C sketch 01 (Appendix 1)

4. TD-21 Structural Inspection Report

Requirement:

1. Replace main deck plating from 2” FWD of FR 3 to 18” FWD of rudder post as shown in S/C sketch 02. Tank and access lap plates forward of FR 3 are in good condition. Existing 39” x

12” mooring chock 48” AFT of FR 0 on CL to remain.

2. Remove and replace 92 square feet (SF) of main deck plate with 20.4# PL (OSS) to meet design intent IAW REF 1. The location of the affected plate is identified by REF 2.

3. Replace Approx. 18 square feet (SF) of 10.2# PL BRKT below deck plating identified by REF 3 without modification to the as-built design.

Government Furnished Materials:

1. All Steel Plate and Steel shapes will be provided by James River Reserve Fleet.

2. Welding rods and materials, grinding discs, and any other incidental materials will be provided by the contractor.

3. JRRF will provide Marine Chemist services and Hot Work Permits for any work performed at

James River Reserve Fleet.

4. If work is performed at the contractor’s facility, the contractor is responsible for providing

Marine Chemist services and Hot Work permits.

5. Fire watch personnel will be provided by the contractor regardless of the location the work is being performed.