USNS MARY SEARS
T-AGS 65
Solic. No.: MLL-16-T65-0001
DRYDOCKING & UNDOCKING September 21,2016
ITEM NO. 0905 CATEGORY “A” USMMI/MLL/RCS
Revision X
RENEW ZINC ANODES
1.0Abstract:
1.1Renew zinc anodes along ship’s hull and sea chests.
2.0References/Enclosures:
2.1References:
2.1.1MSC DWG No. 6782814, “Sacrificial Anode Tables”
2.2Enclosures:
2.2.1MSC Standard item no. 73, “Renewing Zinc Plates”
3.0Item location/description:
3.1Location:
3.1.1Table for quantity and location of anodes
Location / Qty / DescriptionSea chest 4-80-5 / 6 / Type ZHS (welded)
Sea chest 4-80-6 / 6 / Type ZHS (welded)
Aux seawater chest 4-115-1 / 2 / 12 type 35-z (weld) & 2 type 10-z (weld)
Bow thruster / 14 / 12 type 35-z (weld) & 2 type 10-z (weld)
Z-drive (port) / 9 / 7 type 60-z (weld) & 2 type 10-z (weld)
Z-drive (stbd) / 9 / 7 type 60-z (weld) & 2 type 35-z (weld)
4.0USMMI Furnished Equipment/material/services:
4.1Paint
5.0Notes:
5.1The Contractor and all Sub-Contractors, 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 Sub-Contractors, regardless of tier, must comply with the requirements of all applicable GTR's including but not limited to GTR's 1 through 7 and 21 through 29. GTRs can be retrieved from the Internet at the following URL:
5.2The Contractor and all Sub-Contractors, 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 are found in Work Item 0001.
6.0Quality Assurance Requirements:
6.1All work shall be accomplished to the satisfaction of the Port Engineer.
6.2 All workmanship, materials and testing shall be in accordance with the latest ABS Rules for Building and Classing Steel Vessels and to the satisfaction of and in presence of the ABS Surveyor, Manufacturer’s Representatives, Port Engineer and MSCREP.
7.0Statement of Work:
7.1Arrangements/Outfitting:
7.1.1The Contractor is to provide all labor, tools, material, parts and staging to complete these repairs.
7.1.2The Contractor is to temporarily remove any interferences necessary to complete these repairs.
7.1.3No additional work is to be accomplished without a Condition Report and prior written approval by the USMMI Port Engineer. The USMMI Port Engineer is the single point of contact authorized to address technical questions.
7.1.4The contractor is to complete a visual inspection of the hull zinc anodes and submit, to the port engineer, a report listing the percent of deterioration.
7.2Structural:
7.2.1The Contractor is to provide an ABS approved weld procedure for welding new zincs in place.
7.2.2The Contractor is to ensure that compartments in way of zinc anode replacements have been certified safe for men- safe for hot work by a certified marine chemist or equivalent qualified person as designated by the local governmental agency.
7.3Mechanical/Fluids:
7.3.1Discard and remove existing zinc anodes as scrap.
7.3.2Zinc anodes shall be removed prior to underwater hull blasting and installed after all painting has been completed.
7.3.3Provide & install new zinc anodes in accordance with reference 2.1.1
7.4Electrical: None additional
7.5Electronic: None additional
7.6 Preparation of Drawings:
7.6.1Submit an as found condition report of the existing zincs.
7.6.2REPORTS - After all zincs are replaced submit an as released condition report on the zincs.
7.7Inspection/Testing:
7.7.1After all work has been complete inspect each zinc to verify it is properly attached and any protective cover temporarily installed to protect the zinc from being panted is completely removed.
7.8Painting:
7.8.1All side shell plating, tanks and void paint that is damaged during the installation of the new zincs is to have the damage paint area mechanically cleaned and then repainted to conform to the existing paint system.
7.9Marking: None additional
7.10 Manufacturer’s Representative: None
8.0General Requirements: None
9.0
Enclosure 2.2.1
Standard Item No. 73, revised 2 April 1993
Renewing Zinc Plates
Accomplish a visual inspection of the hull zinc anodes. Submit, to the port engineer, a report listing the percent of deterioration of the zincs.
Ensure that compartments in way of zinc plate replacement have been certified safe for men- safe for hot work by a certified marine chemist.
Designated deteriorated, defective or missing zinc plates shall be replaced with new zinc protectors with cast-in straps.
Remove existing defective hull zincs and studs. Where studs have been tapped into castings, chip off the protruding portion, weld all around and grind smooth. Install new zinc anodes and studs, including nuts and washers in accordance with NAVSEA drawing 803-921865, revision "n", which forms and becomes a part hereof.
The new zinc protectors shall be composed of low-iron special high grade zinc, equal to specification mil-a-18001, with cast-in steel straps for attaching to hull structure by welding, and with studs for attachment via bolting to the hull. The zinc protectors, 12" long x 6" wide x 1-1/4" thick. The anodes shall be installed, where practicable, in a fore and aft line on a clean surface.
Sacrificial zinc surfaces shall not be painted. After anode installation, external steel attachment points (straps and studs) shall be painted to conform with the adjacent hull painting system. Straps shall not be painted before installation.
Mask or grease the zincs to preclude anti-fouling paint from adhering to zincs after installation. Remove masking or grease prior to undocking.
Quantities and locations of the anodes to be dealt with shall be as set forth in the basic specification.
VR16-00930905- 1