1、Comments, suggestions, or questions on this document should be addressed to: Commander, Naval Sea Systems Command, ATTN: SEA 05M2, 1333 Isaac Hull Avenue, SE, Stop 5160, Washington Navy Yard DC 20376-5160 or emailed to CommandStandardsnavy.mil, with the subject line “Document Comment”. Since contact
2、 information can change, you may want to verify the currency of this address information using the ASSIST Online database at http:/assist.daps.dla.mil. AMSC N/A FSC 5340 INCH-POUND MIL-DTL-24625A(SH) 02 April 2009 SUPERSEDING MIL-A-24625(SH) 14 November 1983 DETAIL SPECIFICATION ANODES, IMPRESSED CU
3、RRENT CATHODIC PROTECTION - PLATINIZED TYPE MIL-A-24625, dated 14 November 1983, is hereby reactivated and may be used for either new or existing design acquisition. This specification is approved for use by the Naval Sea Systems Command, Department of the Navy, and is available for use by all Depar
4、tments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specification covers platinized anodes for impressed current cathodic protection applications. 1.2 Classification. Platinized anodes are of the following types, grades, classes, and applications as specified (see 6.2). 1.2.1
5、Types. a. Type I - Standard anode b. Type II - Diver replaceable anode 1.2.2 Grades. a. Grade A - Wire anode b. Grade B - Plate anode c. Grade C - Rod anode 1.2.3 Classes. a. Class 1 - Surface ship b. Class 2 - Submarine 1.2.4 Applications. a. Application A - Non-pressure underwater hull b. Applicat
6、ion B - Pressure hull c. Application C - Tank d. Application D - Propulsor Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-24625A(SH) 2 1.3 Part or identifying number (PIN). PINs to be used for platinized anodes acquired to this specification
7、 are created as follows: (see 1.2.1 through 1.2.4 for PIN Code designations and 6.2) M 24625 - X X X X Prefix for Military Specification Specification Number Type (see code below) Grade (see code below) Class (see code below) Application (see code below) Type Code Grade Code Class Code Application C
8、ode Type Code Grade Code Class Code Application Code I 1 A A 1 1 A A II 2 B B 2 2 B B C C C C D D Example: M24625-1A1A M24625-2B2B 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include docum
9、ents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of documents cited in sections 3, 4, or 5
10、 of this specification, whether or not they are listed. 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these docume
11、nts are those cited in the solicitation or contract. DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-S-901 - Shock Tests, H.I. (High-Impact) Shipboard Machinery, Equipment, and Systems, Requirements for MIL-DTL-915 - Cable, Electrical, for Shipboard Use, General Specifications for MIL-C-24217 - Connectors,
12、 Electrical, Deep Submergence, Submarine MIL-C-24231 - Connectors, Plugs, Receptacles, Adapters, Hull Inserts, and Hull Insert Plugs, Pressure-Proof, General Specification for (Copies of these documents are available online at http:/assist.daps.dla.mil/quicksearch/ or http:/assist.daps.dla.mil,or fr
13、om the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.) Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-24625A(SH) 3 2.2.2 Other Government documents, drawings, and publications. The followin
14、g other Government documents, drawings, and publications form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract. NAVSEA S9320-AM-PRO-020 - Underwater Cable Assembly and Encapsulated Compon
15、ents, Fabrication, Repair, and Installation Manual; Vol. II, Molding and Inspection Procedures for Fabricating Connector Plugs for Submarine Outboard Cables (Copies of this document are available from Naval Systems Data Support Activity (NSDSA) Commander, Code 5E30DP Bldg 1388, NAVSURFWARCENDIV NSDS
16、A, 4363 Missile Way, Port Hueneme CA 93043-4307 or online at https:/mercury.tdmis.navy.mil.) 2.3 Non-Government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicita
17、tion or contract. ASTM INTERNATIONAL ASTM B487 - Standard Test Method for Measurement of Metal and Oxide Coating Thickness by Microscopical Examination of a Cross Section (DoD adopted) ASTM B489 - Standard Practice for Bend Test for Ductility of Electrodeposited and Autocatalytically Deposited Metal
18、 Coatings on Metals ASTM B567 - Standard Test Method for Measurement of Coating Thickness by the Beta Backscatter Method (DoD adopted) ASTM B568 - Standard Test Method for Measurement of Coating Thickness by X-Ray Spectrometry (DoD adopted) ASTM B571 - Standard Practice for Qualitative Adhesion Test
19、ing of Metallic Coatings (DoD adopted) ASTM B602 - Standard Test Method for Attribute Sampling of Metallic and Inorganic Coatings ASTM B748 - Standard Test Method for Measurement of Thickness of Metallic Coatings by Measurement of Cross Section with a Scanning Electron Microscope ASTM D543 - Standar
20、d Practices for Evaluating the Resistance of Plastics to Chemical Reagents (DoD adopted) ASTM E8 - Standard Test Methods for Tension Testing of Metallic Materials (DoD adopted) ASTM E290 - Standard Test Methods for Bend Testing of Material for Ductility (DoD adopted) ASTM E1003 - Standard Test Metho
21、d for Hydrostatic Leak Testing (Copies of these documents are available from ASTM International, 100 Barr Harbor Dr., P.O. Box C700, West Conshohocken, PA 19428-2959 or online at http:/www.astm.org.) 2.4 Order of precedence. In the event of a conflict between the text of this document and the refere
22、nces cited herein, the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-24625A
23、(SH) 4 3. REQUIREMENTS 3.1 First article. When specified (see 6.2), a sample shall be subject to first article inspection in accordance with 4.2. 3.2 Recycled, recovered, or environmentally preferable materials. Recycled, recovered, or environmentally preferable materials should be used to the maxim
24、um extent possible, provided that the material meets or exceeds the operational and maintenance requirements, and promotes economically advantageous life-cycle costs. 3.3 Construction. 3.3.1 Anodes. Anodes shall be constructed of platinized niobium or tantalum (for Class I only), with the exception
25、of Grade C anodes. 3.3.1.1 Rod anodes. Grade C rod anodes shall be made as follows. The base for application of platinum shall be a rod (minimum of 0.375 inches in diameter) consisting of a copper core clad with niobium. The ratio of copper to niobium shall be 60 to 40 by cross-sectional area. The d
26、iameter of the anode rod and thickness of platinum cladding shall be sufficient to achieve the desired anode output characteristic and life (see 3.5.1 and 3.6.1). 3.3.1.2 Wire anodes. The specimen shall register a maximum resistance of 1.69 ohms per 100 feet at temperature 204 C. If the resistance i
27、s greater is greater than 1.69 ohms per 100 feet, the specimen shall be declared unsatisfactory (see 4.4.6). 3.3.2 Anode holder. Anode holders shall be able to resist dissolution in accordance with 4.4.8. Grade C anodes shall withstand bending during field application to a radius greater than or equ
28、al to 3 inches. Edges shall provide a suitable and adequate bonding surface for surrounding coating. Holders shall be shock tested as specified in 4.4.7. 3.4 Material. 3.4.1 Platinum plating. The platinum plating shall consist of 99.9 percent pure platinum on an etched surface. Thickness of the plat
29、ing shall be determined through calculations of dissolution at 50 percent of maximum current to last for 20 years, but, in no case, less than 0.002-inch. Verification of the calculations must be provided to the technical authority. 3.4.1.1 Adhesion. Adhesion of the platinum to the substrate shall be
30、 by a metallurgical bonding method (e.g., swaging, rolling, welding, explosion bonding). Electroplating of the platinum to the substrate is not allowed, except as approved by NAVSEA. 3.4.2 Niobium substrate. The substrate shall be 99.9 percent pure, annealed niobium. 3.4.2.1 Rod anodes. Within the b
31、ase rod, the ratio of copper to niobium shall be 60 to 40 by cross-sectional area. The copper core shall be commercially pure annealed copper. The anode shall bend as specified in 4.4.3. Grade C rod anodes shall exhibit no visual cracking of the platinum plating when tested in accordance with 4.4.2
32、and 4.4.3. 3.4.3 Electrical cable. All electrical cable shall conform to MIL-DTL-915 with type, gauge, and length to be determined by ship procurement specifications. Cabling shall pass chemical resistance tests found in 4.4.8. 3.4.4 Watertight connection. Following hydrostatic cycling, there shall
33、be no evidence of mechanical damage, water leakage, or impaired electrical characteristics. Additional requirement for Class 2 anodes are contained in NAVSEA Technical Manual, NAVSEA S9320-AM-PRO-020. The following electrical characteristics requirements shall be met following the watertight connect
34、ion test (see 4.4.5). 3.4.4.1 Electrical resistance. The resistance measured from cable to anode shall be less than 0.01 ohm. This shall be measured using a meter with a resolution better than 0.1 milliohm. 3.5 Workmanship. 3.5.1 Platinized niobium. The surface of the platinized niobium shall be smo
35、oth and free of visible dents, cracks, kinks, and other defects of a similar nature that may affect serviceability. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-24625A(SH) 5 3.5.1.1 Platinized niobium rods (Grade C). Grade C anodes, when b
36、ent, shall be free of imperfections, including cracking and non-adhesion, when viewed at up to 4 times magnification. Ductility shall be tested in accordance with 4.4.3. 3.5.1.2 Adhesion. Adhesion of platinum plating to niobium substrate shall be tested in accordance with 4.4.2. The coating shall fo
37、llow the guidelines for satisfactory adhesion as described in each relevant test found in ASTM B571. 3.5.2 Electrical cable. The surface of the electrical cable shall be without kinks, dents, cracks, and other defects that may affect serviceability. 3.6 Reliability and maintainability (R&M). 3.6.1 A
38、node life. Anodes shall have an expected life equal to 50 percent of the rated output for a 20-year life, but, in no case, less than 0.002-inch. The consumption factor to be assumed is 20 milligrams/Amp-year. The density of platinum is 21.45 grams/centimeters-cubed. 3.6.1.1 Type II anode replacement
39、 time. Diver replaceable anodes shall have a mean time to repair (MTTR) of one hour without the use of a cofferdam. All Type II anode metallic components exposed to seawater by the installation process shall be fabricated from a platinum-plated niobium material to prevent corrosion upon reactivation
40、 of the ICCP anode. 3.7 Operational requirements. Maximum operating current, operating (applied) voltage-to-current ratio, and voltage at anode working surface when at maximum operating current under standard conditions shall be as specified (see 6.2). 4. VERIFICATION 4.1 Classification of inspectio
41、ns. The inspection requirements specified herein are classified as follows: a. First article inspection (see 4.2) b. Conformance inspection (see 4.3) 4.2 First article inspection. First article inspection shall be performed on three sample anodes. This inspection shall include all tests of 4.4. 4.3
42、Conformance inspection. Conformance inspection shall include the tests of 4.4.1, 4.4.4, 4.4.6, and 4.4.8. 4.3.1 Lot. For the purpose of sampling, a lot shall consist of all anodes of the same type from the same production run offered for delivery at one time. However, this lot shall not exceed a max
43、imum of 200 prepared anodes or 1,000 feet (ten 100-foot coils) of platinized niobium wire. 4.3.2 Sampling for examination. A random sample of prepared anodes shall be selected from each lot in accordance with ASTM B602 at verification level II. Each sample specimen shall be examined to assure compli
44、ance with 3.4.1 and 3.4.2. 4.3.3 Sampling for testing. Sampling for the purpose of testing shall be conducted as dictated by the individual test procedures of 4.4. 4.4 Test procedures. 4.4.1 Appearance. The platinum coating shall be examined at up to 10 times magnification for conformance to the req
45、uirements of appearance as specified in 3.5.1. 4.4.2 Adhesion. Adhesion shall be tested in accordance to ASTM B571. Tests referring to palladium coating shall be used for the platinum coating of the anodes. Grade A anodes shall be tested in accordance with ASTM E8 tension testing of metallic materia
46、ls. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-24625A(SH) 6 4.4.3 Ductility. Testing procedures ASTM E290 and B489 shall be followed for the ductility testing of the substrate and the platinum coating, respectively. Grade A anodes shall
47、be tested in accordance with ASTM E8 tension testing of metallic materials. Grade C anodes shall have a ductility rating capable of making a 180-degree bend over a 3-inch radius. 4.4.4 Platinum thickness. Platinum thickness shall be determined by methods outlined in ASTM B487, ASTM B567, ASTM B568,
48、or ASTM B748. The platinum thickness shall comply with 3.4.1. If the substrate is rough relative to the coating thickness, the interface of the coating cross-section may be too irregular to permit accurate measurement of the average thickness in the field of view. If this occurs, another sample shal
49、l be taken from the lot. If both samples are too irregular to obtain an average, the lot shall be rejected. 4.4.5 Watertight connection. The sample specimens used for destructive adhesion tests (see 4.4.2) may be used as specimens for the watertight connection test. Anodes shall be tested using ASTM E1003 or MIL-C-24217 for hydrostatic pressure testing. For purposes of determining test ranges, Class 2 connections are considered to operate wit
