63110_CffrdmInstl_418.doc

63110_RTK _0519_418

63110_GBS_0317_418

WORK ITEM 1: Cofferdam, Install

1. SCOPE

1.1 Intent. This work item describes the requirements for the Contractor to install cofferdams at the sea chests related Work Item: Auxiliary Sea Water Piping, Renew.

1.2 Government-furnished property.

None.

2. REFERENCES

Coast Guard Drawings

Coast Guard Drawing 418A-WMSL-101-005, Rev -, Shell Expansion Scantlings

Coast Guard Drawing 750-WMSL-100-031, Rev J, Unit 2300 Structure - Inner Bottom - FR 52 to FR 64

Coast Guard Drawing 750-WMSL-520-001, Rev H, Seawater Cooling System Diagram

Coast Guard Publications

Surface Forces Logistics Center Standard Specification 0000 (SFLC Std Spec 0000), 2014, General Requirements

Other References

Naval Sea Systems Command (NAVSEA) S0600-AA-PRO-160, 8/15/2008, Underwater Ship Husbandry Manuals - Chapter 16 (Cofferdams)

3. REQUIREMENTS

3.1 General.

3.1.1 CIR. The Contractor shall submit a CIR for the inspections listed in the following paragraph(s):

None.

3.1.2 Tech Rep.

Not applicable.

3.1.3 Protective measures. The Contractor shall furnish and install all protective coverings to seal off and protect all non-affected vessel's components, equipment, and spaces near the work area against contamination during the performance of work. Upon completion of work, the Contractor shall remove all installed protective measures, inspect for the presence of contamination, and return all contaminated equipment, components, and spaces to original condition of cleanliness.

3.1.4 Interferences. The Contractor shall handle all interferences in accordance with SFLC Std Spec 0000, paragraph 3.3.5 (Interferences).

3.1.5 Work coordination. The Contractor shall coordinate work on this item with following Work Item:

· Auxiliary Seawater Piping, Renew.

3.2 Work Location. The concerned work areas are:

· Aft Main Machinery Room (AMMR) starboard sea chest for MPDE #1

· AMMR port sea chest for MPDE #2

· AMMR MPDE seawater overboard discharge

3.3 Cofferdam Fabrication. The Contractor shall fabricate and install a cofferdam over the port and starboard sea chests for MPDE #1 and #2 and the MPDE seawater overboard discharge to prevent water intrusion. See Coast Guard Drawings 418A-WMSL-101-005, 750-WMSL-100-031, and 750-WMSL-520-001 for guidance.

3.3.1 Cofferdam fabrication and installation shall be accordance with the NAVSEA S0600-AA-PRO-160.

3.3.2 The Contractor shall remove cofferdams at the completion of auxiliary sea water piping renewal.

3.3.3 Inspect the structure surrounding the cofferdam for deterioration and corrosion and submit a CFR.

4. NOTES

This section is not applicable to this work item.