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نویسندگان
SCOPE
1.1 This Part of IPS-M-TP-750 covers the minimum requirements for supply, identification, inspection and testing of galvanic (sacrificial) anodes made of Magnesium or Zinc.
1.2 The magnesium alloy anodes conforming to this Part of Standard specification are intended for use in corrosion protection in sea water or under water surfaces of ships, vented ballast tanks of oilers, piers and dock structures, and other underwater (submerged) metallic structures. Galvanized steel structures may also be protected.
1.3 The zinc alloy anodes conforming to this Part of Standard specification are intended for use in corrosion prevention in sea water of ship hulls, steel and aluminum equipments and structures, sea chests, sonar domes and the sea water side of condensers and other heat exchangers.
2. REFERENCES
Throughout this Standard the following dated and undated standards/codes are referred to. These referenced documents shall, to the extent specified herein, form a part of this standard. For dated references, the edition cited applies. The applicability of changes in dated references that occur after the cited date shall be mutually agreed upon by the Company and the Vendor. For undated references, the latest edition of the referenced documents (including any supplements and amendments) applies.
ASTM (AMERICAN SOCIETY FOR TESTING AND MATERIALS)
A 106 "Specification for Seamless Carbon Steel Pipe for High-Temperature Service"
A 185 "Specification for Steel Welded Wire, Fabric, Plain, for Concrete Reinforcement"
BSI (BRITISH STANDARDS INSTITUTION)
BS 1501 "Steels for Pressure Purposes: Plates"
BS 3602 "Specification for Steel Pipes and Tubes for Pressure Purposes: Carbon and Carbon Manganese Steel with Specified Elevated Temperature Properties"
ISO (INTERNATIONAL ORGANIZATION FOR STANDARDIZATION)
ISO 8501-1 "Preparation of Steel Structures Before Application of Paints and Related Products-Visual Assessment of Surface Cleanliness"
3. UNITS
This Standard is based on International System of Units (SI), except where otherwise specified.
4. TECHNICAL DOCUMENTS
The technical bid shall include the following:
4.1 Manufacturing drawings or catalogues for offered anodes: including dimensions, tolerances, steel insert grade, alloy type and weights.
4.2 Production procedures that cover all stages of the manufacturing process, from receipt of raw materials to finishing and packing for shipment, including:
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- chemical analysis;
- surface preparation;
- measurements of weights, dimensions, bowing, twisting, crack size, etc.;
- inspection and testing procedures, and frequencies;
- anode manufacture;
- identification of rejected anodes.
4.3 Insert bending, welding and preparation procedures: including acceptance limits for wall thinning and ovality, nondestructive testing procedures, surface profile measurements.
4.4 Electrochemical test procedures, including acceptance criteria, description of test apparatus, measurement methods and preparation and cleaning of samples.
4.5 Preservation, packing and shipping procedures, such that anodes are not damaged or deformed and do not deteriorate during handling, delivery to the fabrication yard, storage: including methods, materials and any requirement for periodic inspections.
5. MATERIALS AND MANUFACTURE
5.1 General
5.1.1 The electrochemical properties are highly dependent on the content of alloying elements and impurity elements. The anode manufacturer shall thus prove his capability of delivering anodes which satisfy this Part of Standard specification.
5.1.2 Small deviations from the specification in the alloy composition may significantly reduce the protective properties. Generally it is of importance that the fabrication procedure ensures that the melt is not polluted by iron or other impurities. Furnaces, pumps, pipes, etc., shall be non-metallic or properly lined.
5.1.3 The quality control at the anode manufacturing plant shall include control systems on the following:
- Raw materials, i.e., checking of documentation.
- Production equipment and process.
- Testing during and after production.
- Identification of anodes.
- Chemical analysis.
- Weight and dimensional tolerances.
- Surface condition of produced anodes.
- Documentation (material certificates).
5.1.4 The manufacturer shall submit the Purchaser his quality assurance and control plan.
5.2 Magnesium Anodes
The Magnesium anodes shall meet the requirements of US Military Specification MIL-A-21412A (ships), unless specified otherwise by this Part of Standard specification.
5.3 Zinc Anodes
The zinc anodes shall meet the requirements of US Military Specification MIL-A-18001 H, unless specified otherwise by this Part of Standard specification.
5.4 Production Testing
The manufacturer shall carry out the following tests:
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5.4.1 A full spectrographic analysis of each cast. The results shall meet the requirements of US Military specification MIL-A-21412A (for magnesium anodes) or MIL-A-18001 H (for zinc anodes).
5.4.2 A short-term voltage test for zinc anodes only. Duration of test 3 hours minimum, current density 0.75 mA/cm², in sea water (natural or synthetic) of 20°C.
Anode potential (active) to be minus 1000 mv (saturated calomel) or more negative. Anode potential (at rest) to be minus 1050 mv (saturated calomel). The test shall be carried out for each cast.
5.4.3 A destructive testing of one anode of each anode type/design, where net weight of the anode exceeds 100 kg, to check the bonding between anode material and steel core in cross-sectional areas.
The anode material shall be bonded to the steel core over a minimum of 90% of the total surface, while no individual discontinuity or void in the bonding shall exceed 25 mm in length.
6. REQUIREMENTS
6.1 Quality of Anode Castings
6.1.1 The as-cast anode surface shall be free of surface slag or other embedded material.
6.1.2 Cracks are not acceptable, except in the form of micro (hairline) cooling cracks. Maximum width 1 mm.
6.1.3 Shrinkage cavities shall not exceed 10 mm in depth, as taken from the anode surface. Slag inclusions are not acceptable.
Tolerance on the dimensions of anodes, position of anode inserts and gross weight of anodes, to be plus and minus 2%.
6.2 Quality of Steel Inserts
Any type of steel core, insert, or bracket shall be fabricated from fully-killed low-carbon steel, pipe material to be ASTM A 106 Gr. B or BS 3602-HFS27, and plate/strip to be ASTM A 185 Grade C or BS 1501-151 Gr. 26A, to be substantiated by mill certificates.
Steel cores and inserts shall be blast-cleaned to Grade Sa 2½ according to ISO 8501-1, and have this finish at the time of casting.
6.3 Electrical Resistance
When determined in accordance with the test method in Appendix C, the electrical resistance of the anode to core or, if appropriate, of the anode to the end of the cable, shall be not greater than 0.01 for the life of the anode. Ω
6.4 Identification of Anodes
Each anode shall be clearly marked with the type of material (trade name), the cast number, and a piece serial number. The numbers of any rejected anodes shall not be used again for replacement anodes.
7. INSPECTION
Inspection shall cover the following as a minimum:
a) Dimensional checking, identification, weight, and quality of castings on at least 5% of the number of anodes from each cast.
b) Quality of steel inserts before casting, and surface preparation on at least 5% of inserts for the batch of anodes from each cast.
c) Quality of steel-anode bonding on the anode from each order, selected for destructive testing.
d) Inspection of results of spectro analysis, voltage tests, and capacity tests, done by manufacturer.
e) After transport to installation site, a final visual check to be carried out to ensure that anodes have not been damaged during transport and handling.
8. ACCEPTANCE/REJECTION
Acceptance/rejection of anodes will be on a total inspection of all anodes.
Where any of the requirements, mentioned in this Part of Standard specification, are not met, the anodes and the relevant batch of anodes will be rejected.
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9. ORDERING INFORMATIO
(S
10. SUPPLIED DOCUMENTATION
owing documentation shall b
- Certificate No. and date.
- Designation of product.
- The anode batch and cast numbers.
- Details of anode casting wei
- Steel core mill certification.
- Results of any destructive testing.
- Results of any non-destructiv
- Electrochemical test results.
- Anode alloy chemical analysis results.
- Material specification and trade na
- The anode manufacturer.
- The Company’s order and proje
11. MARKING OF CONTAINERS
llet shall be plainly marked with the following information:
Name: ................……………………………………………………………………..……………
Specification: IPS-M-TP-750: Part 4 ......................................………………..…………….
Order No.: .........………………………………………………….………………..…………….
M.E.S.C No.: .....………………………………………………….………………..…………….
Anode class, type and style: ..................................................………………..…………….
Anode weight (net and gross): ..............................................………………..…………….
Anode dimensions: ................................................................………………..…………….
Batch No.: .........………………………………………………….………………..…………….
Stock No.: ..........…………………………………………………………………..…………….
Date of manufacture: ............................................................………………..…………….
Quantity: ............…………………………………………………………………..…………….
Note:
E
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APPENDICES
APPENDIX A
DATA SHEET
(TO BE SUBMITTED BY THE PURCHASER)
FOR
IPS-M-TP-750: Part 4 ZINC ALLOY ANODES
The anodes shall be in accordance with the latest edition of above Iranian Petroleum Standard with the following specific requirements:
- Project title: ............................................ - Date: .........................................
- Indent No.: ............................................. - Purchaser:..................................
- M.E.S.C. No.: ........................................ - No. of Anodes: .........................
- Anode Classification (for selection see MIL-A-18001 H, Classification).
b Class 1:
b Type ZHS : Length: Width: Thickness:
b Type ZHB:
b Type ZHC: Length: Width: Thickness:
b Type ZSS
b Type ZTS
b Type ZEP: b Style A
b Style B Diameter:
b Style C
b Type ZBP
b Type ZDM Diameter:
b Class 2:
b Type ZRN: Pipe or Bolt Diameter:
- Packing requirements (other than those required by MIL-A-18001 H, preparation for delivery):
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APPENDIX B
DATA SHEET
(TO BE SUBMITTED BY THE PURCHASER)
FOR
IPS-M-TP-750: Part 4 MAGNESIUM ALLOY ANODES
The anodes shall be in accordance with the latest edition of above Iranian Petroleum Standard with the following specific requirements:
- Project title: ............................................ - Date: .........................................
- Indent No.: ............................................. - Purchaser:..................................
- M.E.S.C. No.: ........................................ - No. of Anodes: .........................
- Anode Classification (for selection see MIL-A-21412 A, Classification).
Class: Type: Style:
- Anode Shape (for types MOP-50 and MOB-50 anodes, if technical requirements so dictates):
b "D" b Round b Square
- Packing requirements (other than those required by MIL-A-21412 A, preparation for delivery):
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APPENDIX C
METHOD FOR THE DETERMINATION OF THE ANODE-TO-CORE
RESISTANCE OF GALVANIC ANODES
C.1 General
This Appendix describes the method for the determination of the anode-to-core resistance of galvanic (sacrificial) anodes used for cathodic protection.
C.2 Principle
The voltage across the anode metal and anode core is measured when a known current is passed between them. The anode-to-core resistance is then computed by dividing the measured voltage by the known current.
C.3 Apparatus
The following apparatus is required:
a) A d.c. supply of 5 A capacity, with an adjustable current control capable of smooth variation from 5 A to near zero. It shall be capable of generating an on-load-voltage sufficient to pass a current of 5 A through a resistance of not less than 1 Ω.
b) An ammeter capable of reading to at least 5 A d.c. with a maximum error of ±1% at full scale deflection. This ammeter may be integral with the d.c. supply (see Item (a)).
c) A millivoltmeter of the electrically protected type capable of reading to 50 mV d.c., with a maximum error of ±1%.
d) Suitable test leads and clamps or clips to connect Items (a), (b) and (c) to the anode and the core. The clamp system shall be of such quality to ensure that the connection resistance to each point is less than 0.05 Ω.
C.4 Circuit
The circuit shall be arranged as shown in Fig. C.1. The leads connecting the millivoltmeter to the anode and the anode core. Shall be independent of the leads from the power supply. All connections shall be properly made to minimize contact resistance.
If the millivoltmeter is connected across the anode metal and the terminal of the cable attached to the anode core, the anode-to-core resistance is obtained by subtracting the cable resistance from the total resistance. The total resistance is computed by dividing the measured potential by the known current.
C.5 Procedure
The procedure shall be as follows:
a) Before connecting the power supply, set the variable current control to ensure a minimum current flow when the circuit is switched on.
b) Connect the power supply. Adjust the variable current control until approximately 5A is registered on the ammeter.
c) Read the voltage difference as indicated by the millivoltmeter.
(to be continued)
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APPENDIX C (continued)
d) Calculate the anode-to-core resistance (R), in ohms, using the following equation:
R = amperes)(in readingammeter (in volts) readingeter millivoltm
e) Reverse both ammeter supply leads and also the millivoltmeter supply leads, and repeat Steps (a) to (d) above. The result of this second calculation of R should be the same as the initial result.
C.6 Report
The test report shall contain the following information:
a) Name of test laboratory.
b) Identification of the equipment used to carry out the test.
c) Identification of the galvanic anode tested.
d) The date on which the test was carried out.
e) The results of the anode-to-core resistance test calculations.
f) Reference to this test method.
SCHEMATIC CIRCUITS FOR MEASUREMENT OF ANODE-TO-CORE RESISTANCE
Fig. C.1
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PART 5
BRACELET TYPE GALVANIC ANODES
FOR
SUBMARINE PIPELINES
(ALUMINUM AND ZINC)
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59
CONTENTS : PAGE No.
1. SCOPE.........................................................................................................................................60
2. REFERENCES.............................................................................................................................60
3. DEFINITIONS AND TERMINOLOGY...........................................................................................60
4. UNITS...........................................................................................................................................63
5. TECHNICAL DOCUMENTS.........................................................................................................63
6. MATERIALS AND MANUFACTURE............................................................................................64
7. ANODE CORE STEEL WORKS...................................................................................................67
8. REQUIREMENTS.........................................................................................................................68
9. INSPECTION................................................................................................................................70
10. ACCEPTANCE/REJECTION......................................................................................................71
11. SUPPLIED DOCUMENTATION.................................................................................................71
12. ORDERING INFORMATION.......................................................................................................71
13. PACKING AND SHIPMENT.......................................................................................................71
14. LABELING.................................................................................................................................72
APPENDICES:
APPENDIX A METHOD FOR THE DETERMINATION OF THE ANODE-TO-CORE......................73
RESISTANCE OF GALVANIC ANODES.........................................................................................73
APPENDIX B METHOD FOR THE DETERMINATION OF THE CONSUMPTION RATE OF ALUMINUM ANODE ALLOYS IMMERSED IN SEAWATER..........................................................76
APPENDIX C METHOD FOR THE DETERMINATION OF THE CLOSED-CIRCUIT POTENTIAL OF ALUMINUM ANODES IMMERSED IN SEAWATER..................................................................79
APPENDIX D DATA SHEET FOR BRACELET GALVANIC ANODES...........................................81
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1. SCOPE
This Part of IPS-M-TP-750 covers the minimum requirements for the material, manufacture, inspection and testing, documentation, and supply of half-shell bracelet type galvanic anodes made of Aluminum and/or Zinc, to be used for the cathodic protection of submarine pipelines.
2. REFERENCES
Throughout this Standard the following dated and undated standards/codes are referred to. These referenced documents shall, to the extent specified herein, form a part of this standard. For dated references, the edition cited applies. The applicability of changes in dated references that occur after the cited date shall be mutually agreed upon by the Company and the Vendor. For undated references, the latest edition of the referenced documents (including any supplements and amendments) applies.
ASTM (AMERICAN SOCIETY FOR TESTING AND MATERIALS)
B6 Standard Specification for "Zinc"
B418 Standard Specification for "Cast and Wrought Galvanic Zinc Anodes"
D1141 Standard Specification for "Substitute Ocean Water"
AWS (AMERICAN WELDING SOCIETY)
D1.1 "Structural Steel Welding Code"
BSI (BRITISH STANDARDS INSTITUTION)
EN 10025 "Hot Rolled Products on Non-alloy Structural Steels and Their Technical Delivery Conditions"
BS 729 "Hot Dip Galvanized Coatings on Iron and Steel Articles"
BS EN 12329 "Corrosion Protection of metals Electrodeposited Coating of Zinc with Supplementary Treatment on Iron or Steel"
ISO (INTERNATIONAL ORGANIZATION FOR STANDARDIZATION)
8501-1 "Preparation of Steel Substrates before Application of Paints and Related Products-Visual Assessment of Surface Cleanliness"
3. DEFINITIONS AND TERMINOLOGY
Anode consumption rate
The rate of alloy mass consumption for a given current output over a given period; normally stated in kilograms per ampere year.
Cast sacrificial anode
The negative (reactive) component of a galvanic cell, designed to oxidize sacrificially and produce direct electrical current to protect a more electropositive (noble) metal operating in the same electrolyte and produced to a desired shape by the solidification of a molten alloy in a mold or die.
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Cathodic protection
The prevention or reduction of corrosion of metal by making the metal the cathode in a galvanic or electrolytic cell.
Closed circuit potential
The potential of an anode connected to a structure when passing current; normally measured against a reference electrode in a particular environment.
Cold lap
Horizontal discontinuity caused by solidification of the meniscus of partially cast anode as a result of interrupted flow of the casting stream. The solidified meniscus is covered with metal when the flow resumes. Cold laps can occur along the length of an anode.
Cold shut
Horizontal surface discontinuity caused by solidification of a portion of a meniscus during the progressive filling of a mold, which is later covered with more solidifying metal as the molten metal level rises. Cold shuts generally occur at corners remote from the point of pour.
Cracking
Fracture of metal along an irregular path producing a discontinuity similar to a ragged edge. It can occur during the solidification of the anode (hot cracking), during the contraction of the anode after solidification, or under externally applied loads. Hot cracking may be associated with the shrinkage depression that can occur in open-topped molds.
Current capacity
The total current flow available from an anode of given mass of alloy; normally expressed as ampere years per kilogram. This is the inverse of the anode consumption rate.
Current density
The average amount of current entering or leaving a given surface area.
Driving potential
The difference between the open circuit potentials of the anode and the structure.
Dulling of steel
Deterioration in appearance of shot-blasted inserts because of oxidation that causes darkening of the surface but not rust discoloration (see Rust Discoloration).
Electrochemical properties
Those properties of potential and current capacity that characterize a sacrificial anode and can be assessed by quantitative tests.
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Gas holes
The evidence of bubbles within the solidifying metal. The holes can indicate that moisture was on the mold or insert prior to casting, or that the liquid metal contained a high level of hydrogen that had been thrown out of solution to form bubbles during the cooling of the metal.
Gross anode mass
Total mass of an anode, including anode core.
Heat
Also called a "melt" or "cast", it is the unit that defines molten metal and identifies the anodes cast from it. A heat is the product that is cast to a planned procedure in one melting operation in one furnace, without significant interruption. If the casting sequence is interrupted, the anodes produced before, between, and after the interruptions constitute "batches".
Inserts
The form over which the anode is cast and which is used to connect the anode to the structure requiring protection. These are sometimes referred to as "cores".
Net anode mass
Mass of actual anode alloy.
Nonmetallic inclusions
Particles of oxides and other refractory materials entrapped in liquid metal during the melting or casting sequences.
Open circuit potential
The potential of an anode when not connected to a structure; normally measured against a reference electrode in a particular environment.
Porosity
Generally distributed fine holes caused by gas bubbles, shrinkage (formed by the starvation of eutectic material within the dendrite arms during "unfed" solidification), or a combination of the two mechanisms when hydrogen in solution diffuses into the lower pressure shrinkage voids.
Protrusion
Extraneous material on the anode surface. It may interfere with the anode-to-structure fit, appear unattractive, and be a safety hazard if there are sharp edges. Protrusions can be formed by careless filling of the mold or the flash from imperfect fitting of mold sections.
Reference electrode
An electrode which has a stable potential in one or more electrolytes, thus enabling it to be used for the measurement of other electrode potentials at a given temperature.
Rimming (rimmed) steels
An incompletely deoxidized steel. (See ASM Metals Handbook, 7th. Edition for exhaustive definition.)
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Rust discoloration
A brown bloom of iron oxide.
Sample
A representative specimen.
Shrinkage depression
The natural concave surface produced when liquid metal is allowed to solidify in a container without the provision of extra liquid metal to compensate for the reduction in volume that occurs during the liquid-solid transformation. The term also applies to the concave surface produced when liquid metal is solidified in a closed mold in such a manner that the area is not "fed" by the liquid metal provided by the casting’s riser.
Tap sample
A specimen taken from a molten metal stream. Such samples may be taken at the commencement of pouring and then at regular intervals until a final sample is taken at the end of the pour.
Voids adjacent to insert
Visible spaces between anode and insert materials. These can be caused by surface evaporation of moisture from the insert, contraction of the insert, or movement of the insert during casting caused by uneven heating and expansion that distorts the insert and prevents it from returning to its original, desired position within the anode.
4. UNITS
This Standard is based on International System of Units (SI), except where otherwise specified.
5. TECHNICAL DOCUMENTS
The manufacturer and/or supplier shall provide the following procedures with reference to this Standard specification:
5.1 Production procedures that cover all stages of the manufacturing process, from receipt of raw materials to finishing and packing for shipment, including:
- chemical analysis;
- surface preparation;
- measurements of weights, dimensions, bowing, twisting, crack size, etc.;
- inspection and testing procedures, including acceptance criteria, and frequencies;
- anode manufacture;
- identification of rejected anodes.
5.2 Insert bending, welding and preparation procedures: including acceptance limits for wall thinning and ovality, nondestructive testing procedures, surface profile measurements.
5.3 Electrochemical test procedures, including acceptance criteria, description of test apparatus, measurement methods and preparation and cleaning of samples.
5.4 Preservation, packing and shipping procedures, such that anodes are not damaged or deformed and do not deteriorate during handling, delivery to the fabrication yard, storage: including methods, materials and any requirement for periodic inspections.
5.5 The manufacturer and/or supplier shall provide manufacturing drawings as detailed bellow for
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approval. Details to be shown on anode detail drawings for each pipe size shall be as follows:
- Dimensions and tolerances.
- Details of frame design.
- Details of fixing lugs.
- Alloy type.
- Net weight.
- Gross weight.
- Location of markings.
- Details of electrical connections.
5.6 Anode manufacture shall not commence until all relevant documents, manufacturing drawings and the Quality and Inspection plan and supporting procedures have been approved.
5.7 The manufacturer and/or supplier shall submit to the Purchaser his quality assurance and control plan.
6. MATERIALS AND MANUFACTURE
6.1 General
6.1.1 The electrochemical properties are highly dependent on the content of alloying elements and impurity elements. The anode manufacturer shall thus prove his capability of delivering anodes which satisfy this Part of Standard specification.
6.1.2 Small deviations from the specification in the alloy composition may significantly reduce the protective properties. Generally it is of importance that the fabrication procedure ensures that the melt is not polluted by iron or other impurities. Furnaces, pumps, pipes, etc., shall be non-metallic or properly lined.
6.1.3 Manufacturing of anodes shall be carried out using approved production procedures covering each stage of the process from supply of raw materials to finishing and packing for shipment. The procedures shall be fully referenced in an Inspection and Test plan which shall also refer to requirements of this Part of Standard specification, as applicable.
6.1.4 The manufacturer shall ensure that full traceability of all the materials is maintained throughout the manufacturing process.
The manufacturer shall submit the Purchaser his quality assurance and control plan.
6.1.5 The quality control at the anode manufacturing plant shall include control systems on the following:
- Raw materials, i.e.,checking of documentation.
- Production equipment and process.
- Testing during and after production (see 6.3).
- Identification of anodes.
- Chemical analysis (see 6.3.1).
- Weight and dimensional tolerances.
- Surface condition of produced anodes.
- Documentation (material certificates).
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6.2 Alloy Composition
6.2.1 Aluminum anodes
The aluminum anodes shall conform to the chemical composition specified in Table 1 as determined by spectrographic and other methods specified herein.
6.2.2 Zinc anodes
The zinc anodes shall be made from special High Grade Zinc conforming to ASTM specification B 6, with suitable alloying additions. The anodes shall conform to the chemical composition given in Table 2 in order to reduce the susceptibility to intergranular corrosion at elevated temperature.
The zinc anode composition in this specification meets the chemical composition requirements of ASTM specification B418 (Type I) and US Military specification MIL-A-18001 H.
TABLE 1 - CHEMICAL COMPOSITION LIMITS FOR ALUMINUM ANODES
CHEMICAL COMPOSITION,
PERCENT
ELEMENT
min.
max.
Silicon
Iron
Copper
Zinc
Indium
Other Elements:
- Each
- Total
---
---
---
3.0
0.02
---
---
0.10
0.10
0.006
5.0
0.05
0.02
0.05
Aluminum
Remainder
TABLE 2 - CHEMICAL COMPOSITION LIMITS FOR ZINC ANODES
CHEMICAL COMPOSITION,
PERCENT
ELEMENT
min.
max.
Cadmium
Aluminum
Iron
Lead
Copper
Other Elements:
- Each
- Total
0.03
0.1
---
---
---
---
---
0.06
0.2
0.002
0.006
0.005
---
0.1
Zinc
Remainder
Certificates of analysis shall be submitted for all elements above 0.01%, in addition to the elements above listed, and shall state that all other elements are below this limit.
6.3 Production Testing
The manufacturer shall carry out the following production tests:
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6.3.1 Chemical analysis
6.3.1.1 No anode casting shall commence before confirming by chemical analysis that the alloy constituents fall within the range specified in 6.2.
6.3.1.2 A full spectrographic analysis, or an approved alternative, shall be made of representative samples taken at the beginning and end of each melt to prove that the chemical composition is within the limits of the alloy specification stated in 6.2. If one of these analysis is out of the specified range, the heat will be rejected.
6.3.1.3 The equipment used for chemical analysis shall be calibrated at the start of each shift using reference samples. Calibration samples shall be independently certified.
6.3.1.4 If alloying additions are made in holding furnaces or crucibles, then analysis shall be made at the beginning and end of pouring from the holding furnace or crucible.
6.3.1.5 No additions of whatever kind shall be made to the melt following a spectrographic analysis showing the material to be within specification and before commencement of pouring.
6.3.1.6 Each heat shall be assigned a unique number which shall be transferred to all samples taken from that heat and to all records pertaining to that heat. All samples shall be indestructibly marked with the unique heat number.
6.3.1.7 At least two further samples, taken at the same frequency as those for spectrographic analysis, in the form of sticks of approximately 30 mm diameter × 200 mm length shall be retained from each heat for use in electrochemical testing.
6.3.1.8 All samples shall be retained for a minimum of 2 years beyond completion of the supply contract and may be subjected to independent analysis and testing.
6.3.2 Short term voltage testing
A short term voltage test shall be carried out on one representative sample from each heat.
The voltage test shall be carried out in natural seawater or synthetic sea water (to the composition specified in ASTM D 1141) at 20°C.
For aluminum anodes refer to Subclause 8.5.
For zinc anodes the test shall be performed at an anodic current density of 0.75 mA/cm² and duration of test shall be 3 hours min. The anode working potentials shall be respectively minus 1000 mV and minus 1050 mV. VS SCE reference electrode.
6.3.3 Short term capacity testing for aluminum anodes only
A short duration capacity test shall be carried out on one representative sample of each heat.
One-fifth of the number of heats to be tested, with minimum one test per order.
The test procedure shall be in accordance with Appendix B. Anode material capacity shall be determined by weight loss (see 8.4). The Anode capacity shall not be less than 2500 Ah/kg.
6.3.4 Anodes failing the above electrochemical tests acceptance criteria shall be rejected. However, a minimum of two new samples for re-tests may be cut from two different anodes of the same heat number as the original failed test pieces. In case even one of these two give negative results, the entire heat will be rejected, or all the anodes shall be tested individually. In case both of them give acceptable results, the remaining part of the heat is accepted.
6.3.5 Destructive and non-destructive testing
6.3.5.1 One anode shall be selected for sectioning at random from each of 150 produced anodes, in addition to the first sectioned anode taken at the start of production.
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6.3.5.2 The selected anode shall be transverse sectioned by single cuts at 25%, 33% and 50% of the nominal length and once longitudinally.
6.3.5.3 The cut faces, when examined visually without magnification, shall be free from visible slag/dross inclusions.
6.3.5.4 Total porosity in any sectioned surface shall not exceed 0.25% of the alloy area, with no individual pores or void greater than 10 mm².
6.3.5.5 The lack of bonding between the anode and the core shall not exceed 5% of the core peripheral length in any sectioned surface.
6.3.5.6 Should any anode section fail to meet the above criteria, the subsequent anode cast shall be also sectioned. If this also fails, the entire production batch (since the last successful section) shall be quarantined and a series of backchecks made in order to allow acceptance of part batches.
6.3.5.7 Alternatively to destructive testing a non-destructive testing by radiography may be used to check for lack of bond or slag/dross inclusions.
7. ANODE CORE STEEL WORKS
7.1 Insert Material
7.1.1 The anode material shall be cast around a steel insert so designed as to retain the anode material even when it is consumed to its design utilization factor. The steel inserts shall have sufficient strength to withstand all external forces that they may normally encounter.
7.1.2 The anode insert shall meet the requirements of EN 10025 Grade Fe 430C. The maximum carbon content of the steel to be welded shall not exceed 0.23%.
7.1.3 The carbon equivalent of the insert materials shall not exceed 0.45%, determined using the following formula:
Carbon equivalent = C + 6Mn + 5VMoCr++ + 15CuNi+
Where each element is expressed in weight percent.
7.1.4 Rimming steels shall not be used.
7.1.5 All materials shall be identified against original mill certificates.
7.2 Insert Surface Preparation
7.2.1 Inserts shall be stored indoors at a humidity not exceeding 85% with steel temperature maintained at least 3°C above the dew point.
7.2.2 For aluminum anodes, the steel fabrication to be inserted into the cast anode shall be prepared by a dry blast cleaning process to a minimum quality complying with ISO 8501-1, Grade SA 2½ or equivalent standard.
7.2.3 At the time the aluminum anodes are cast, "dulling" of the blast cleaned surface of the insert shall be permitted. Rust discoloration and/or visible surface contamination shall not be permitted.
7.2.4 For zinc anodes, the steel fabrication to be inserted into the cast anode shall be prepared by dry blast cleaning process to a minimum quality complying with ISO 8501-1 Grade SA 2½ or equivalent standard, galvanizing to BS 729,or Zinc electroplating to BS 1706, or equivalent standards.
7.2.5 At the time the zinc anode is cast, "dulling" of blast cleaned or zinc coated steel insert surfaces shall be permitted. Rust discoloration and/or visible surface contamination of the blast
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cleaned or zinc coated surface shall not be permitted.
7.2.6 Inserts not used within 8 hours of blast cleaning, or showing signs of rusting, moisture, grease, oil or other surface contamination, shall be re-cleaned.
7.3 Welding
7.3.1 All fabrication welding and acceptance tests on anode insert shall be in accordance with AWS D1.1, latest edition.
7.3.2 Welding procedures and welder qualifications shall be in accordance with AWS D1.1, latest edition.
7.3.3 All welds shall be visually inspected and be free of deleterious defects. Adequate examination of production welds shall be carried out by appropriate non-destructive testing.
8. REQUIREMENTS
8.1 Anode Shape, Weight and Dimensions
8.1.1 Shape
The shape of anodes, as will be specified by the Purchaser, may be either plain half-shell or tapered half-shell.
Notes:
1) The plain half-shell bracelet is used when the pipe is concrete coated and shall be manufactured so that the internal diameter fits over the outside diameter of the wrap/composition coat and matches the outside diameter of the concrete.
2) The tapered half-shell bracelet is for pipes without concrete, the purpose of the taper being to enable the anodes more easily to traverse the stringer rolls of the lay-barge.
8.1.2 Weight
8.1.2.1 The individual casting (half-shell pairs) net weight shall be within ±3% of the net weight shown on the drawings.
8.1.2.2 All half-shell anodes and their cores shall be weighed individually to confirm compliance. The individual weights shall be recorded. The total supplied net weight shall be no more than 2% above and not below the nominal supplied weight.
8.1.3 Dimensions
8.1.3.1 The anode dimensions shall conform to the tolerances indicated by the manufacturer and/or supplier in the approved drawings.
8.1.3.2 The position of the insert in the casting shall be within 5 mm of the design position, as an average over the length, and not more than 10 mm from the design position at any point.
8.1.3.3 Anodes shall be free from excessive bowing or twisting. The manufacturer shall fabricate a suitable template for the half-shell bracelet anodes. Complete bracelets shall be assembled around
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the template to ensure compliance with the diametrical tolerances specified on the drawings.
8.1.3.4 Anode insert cross section dimensions shall comply with the appropriate specification for the insert material used. Full dimensional checks shall be carried out to ensure compliance with the approved drawing for the insert material used.
8.2 Mechanical Resistance
When an uniaxial force equivalent to 100 kg, or five times the mass of the anode metal, whichever is the greater, is applied to a cast anode containing a core, no movement of the core or any metal insert shall occur.
8.3 Electrical Resistance
When determined in accordance with the test method in Appendix A, the electrical resistance of the anode to core shall be not greater than 0.01 Ω for the life of the anode.
8.4 Consumption Rate of Aluminum Anodes in Seawater
When determined in accordance with the test method in Appendix B, the consumption rate of an aluminum anode in seawater shall not exceed 3.5 kg/A. year.
Note:
The test specified in Appendix B is applicable to aluminum anodes only. Typical consumption rates for zinc anodes in seawater is given in Table 3.
8.5 Closed Circuit Potential of Aluminum Anodes in Seawater
When determined in accordance with Appendix C, the closed-circuit potential of an aluminum anode shall be at least - 1.05 V with respect to a silver/silver chloride reference electrode.
Note:
The test specified in Appendix C is relevant for aluminum anodes only.
TABLE 3 - TYPICAL PROPERTIES OF ZINC ANODES
OPEN CIRCUIT POTENTIAL, Ea.
REFERENCE ELECTRODE
Cu/CuSO4
Ag/AgCl
TYPICAL ANODE CONSUMPTION
RATE IN SEAWATER
kg/A. YEAR
-1.1
-1.05
12
8.6 Surface Irregularities in the Anode Casting
8.6.1 Shrinkage depressions in the casting shall not exceed 10% of the nominal thickness of the anode as measured from the uppermost corner of the depression to its bottom.
8.6.2 The anode casting shall be free from non-metallic inclusions. Cold shuts or surface laps shall not exceed a depth of 10 mm or extend over a total length of more than 150 mm.
8.6.3 All protrusion detrimental to the safety of personnel during handling shall be removed. No further grinding or mechanical treatment of the anode surface shall be permitted.
8.6.4 All anodes shall be inspected visually to confirm compliance with the above.
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8.7 Cracks in Cast Anodes Material
8.7.1 Within the section of sacrificial anodic material wholly supported by the core, transverse cracks shall not be permitted except in the form of micro (hairline) cooling cracks with a maximum width of 2 mm and a length not greater than 75% of the anode bracelet diameter or 200 mm whichever is smaller. A maximum of two cracks per casting (halfshell) shall be allowed. Small close cracks shall be taken as one crack.
8.7.2 No cracks shall be allowed in anodic material unsupported by the core.
8.7.3 Cracks which extend around two or more faces of the anode shall not be permitted.
8.7.4 Longitudinal cracks shall not be permitted.
8.7.5 All castings shall be visually inspected to ensure compliance with the above.
8.8 Anode Connections
8.8.1 Two anode connections, for bonding to the pipe, shall be attached to each bracelet half-shell. Electrical connection to the pipeline shall be by means of four 16 mm² cables per anode to be thermit welded to the pipeline after anode installation.
8.8.2 The lead wires shall be 16 sq.mm single core, stranded soft annealed copper conductor conforming to IEC 228 Class 2, minimum length 250 mm.
8.8.3 The lead wire insulation, as will be specified by the Purchaser, shall be in accordance with one of the following alternatives:
- A single jacket of High Molecular Weight Polyethylene (HMWPE) conforming to ASTM D 1351, having a minimum thickness of 1.5 mm.
- A single jacket of Cross-Linked Polyethylene (XLPE) conforming to ASTM specification D 2655, having a minimum thickness of 1 mm.
- A double jacket of Polyvinyl Chloride (PVC) primary insulation as per ASTM D 2219, sheathed with a Polyvinyl Chloride (PVC) extruded jacket conforming to ASTM D 1047. The average thickness (of insulation and sheath) shall be 2 mm with a 10% tolerance.
8.8.4 Lead wire insulation shall have a minimum 600 volt rating.
8.8.5 Unless otherwise specified, the color of lead wire insulation shall be red.
8.8.6 The insulation shall be applied tightly to the conductor without adhering to it and shall form a compact and homogeneous body. The lead wire insulation shall be completely free of cracks, nicks, scratches, or other discontinuities.
9. INSPECTION
9.1 Responsibility for Inspection and Tests
9.1.1 The manufacturer and/or supplier shall be responsible for carrying out all the tests and inspections (during and after fabrication) required by this Part of Standard specification, using his own or other reliable facilities, and he shall maintain complete records of all such tests and inspections. Such records shall be available for review by the Purchaser.
9.1.2 The manufacturer and/or supplier shall afford the Purchaser’s inspector all reasonable facilities necessary to satisfy him that the material is being produced and furnished in accordance with this Part of Standard specification.
9.1.3 The Purchaser reserves the right to perform any inspections set forth in the specification where such inspections are deemed necessary to assure that supplies and services conform to the
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prescribed requirements. Such inspections in no way relieve the manufacturer and/or supplier of his responsibilities under the term of this Part of Standard specification.
9.1.4 The Purchaser’s inspector shall have access to the material subject to inspection for the purpose of witnessing the selection of the samples, the preparation of the test pieces, and the performance of the test(s). For such tests, the inspector shall have the right to indicate the pieces from which the samples will be taken in accordance with the provisions of this Part of Standard specification.
9.1.5 The manufacturer shall inspect the material covered by this Standard specification prior to shipment and shall furnish to the Purchaser a certificate of inspection stating that each lot has been sampled, tested, and inspected in accordance with this Part of Standard specification and has been found to meet the requirements specified.
9.2 Inspection
9.2.1 Inspection shall cover the following as a minimum:
9.2.1 Dimensional checking, identification, weight, and quality of castings on at least 5% of the number of anodes from each cast.
9.2.2 Quality of steel inserts before casting, and surface preparation on at least 5% of inserts for the batch of anodes from each cast.
9.2.3 Quality of steel-anode bonding on the anode from each order, selected for destructive testing.
9.2.4 Inspection of results of spectro analysis, voltage tests, capacity tests and destructive testing done by manufacture (see 6.3).
9.2.5 After transport to installation site, a final visual check to be carried out to ensure that anodes have not been damaged during transport and handling.
10. ACCEPTANCE/REJECTION
10.1 Acceptance/rejection of anodes will be on a total inspection of all anodes (see 9).
10.2 Where any of the requirements, mentioned in this Part of Standard specification, are not met, the anodes and the relevant batch of anodes will be rejected.
11. SUPPLIED DOCUMENTATION
The following documentation shall be supplied with each anode batch:
- The anode batch and cast numbers.
- Details of anode casting weights (net and gross) and numbers.
- Steel core mill certification.
- Results of any destructive testing.
- Results of any non-destructive testing.
- Electrochemical test results.
- Anode alloy chemical analysis results.
- Material specification and trade name.
- The anode manufacturer.
- The Company’s order No.
- The date of manufacture.
- Certificate of conformity with this Part of Standard specification.
12. ORDERING INFORMATION
(See Appendix D.)
13. PACKING AND SHIPMENT
Anodes shall be bundled, strapped, placed on pallets, or in sturdy crates with supports, pads and binding as necessary to facilitate unloading and minimize damage to anodes during normal handling and transportation.
Cleaning, preservation, and packaging of anodes shall be in accordance with the manufacturer’s commercial practice, provided they are such as to ensure acceptance by common or other carriers for safe transportation to the delivery point.
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14. LABELING
14.1 Identification of Anodes
The following information shall be legibly and durably marked on each anode supplied, or on a label securely fixed to each anode:
a) The name or registered mark of the manufacturer.
b) The alloy designation (trade name).
c) Nominal net mass of the anode.
d) Batch number.
e) Cast number.
Notes:
1) The same identification shall appear on all samples taken for testing.
2) The numbers of any rejected anodes shall not be used again for replacement anodes.
14.2 Marking of Container
Each pallet shall be plainly marked with the following information:
Name: ................…………………………………………………………..……………………..
Specification: IPS-M-TP-750: Part 5 ......................................………..……………………..
Order No.: .........…………………………………………………..………..……………………..
M.E.S.C No.: .....………………………………………………….………..……………………..
Anode Type: ......…………………………………………………………..……………………..
Anode Weight (Net and Gross): ............................................………..……………………..
Anode Dimensions: ...............................................................………..……………………..
Batch No.: .........…………………………………………………………..……………………..
Stock No.: ..........………………………………………………..………..……………………..
Date of Manufacture: ...........................................................………..……………………..
Quantity: ............……………………………………………….………..……………………..
Manufacturer’s Name and Address: ...................................………..……………………..
Note:
Each pallet shall be clearly marked "FRAGILE".
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APPENDICES
APPENDIX A
METHOD FOR THE DETERMINATION OF THE ANODE-TO-CORE
RESISTANCE OF GALVANIC ANODES
A.1 General
This Appendix describes the method for the determination of the anode-to-core resistance of galvanic (sacrificial) anodes used for cathodic protection.
A.2 Principle
The voltage across the anode metal and anode core is measured when a known current is passed between them. The anode-to-core resistance is then computed by dividing the measured voltage by the known current.
A.3 Apparatus
The following apparatus is required:
a) A d.c. supply of 5 A capacity, with an adjustable current control capable of smooth variation from 5 A to near zero. It shall be capable of generating an on-load-voltage sufficient to pass a current of 5 A through a resistance of not less than 1 . Ω
b) An ammeter capable of reading to at least 5 A d.c. with a maximum error of ±1% at full scale deflection. This ammeter may be integral with the d.c. supply (see Item (a)).
c) A millivoltmeter of the electrically protected type capable of reading to 50 mV d.c., with a maximum error of ±1%.
d) Suitable test leads and clamps or clips to connect Items (a), (b) and (c) to the anode and the core. The clamp system shall be of such quality to ensure that the connection resistance to each point is less than 0.05 Ω.
A.4 Circuit
The circuit shall be arranged as shown in Fig. A.1 (a) or (b), as applicable. The leads connecting the millivoltmeter to the anode and the anode core (or cable), shall be independent of the leads from the power supply. All connections shall be properly made to minimize contact resistance.
If the millivoltmeter is connected across the anode metal and the terminal of the cable attached to the anode core, the anode-to-core resistance is obtained by subtracting the cable resistance from the total resistance. The total resistance is computed by dividing the measured potential by the known current.
A.5 Procedure
The procedure shall be as follows:
a) Before connecting the power supply, set the variable current control to ensure a minimum current flow when the circuit is switched on.
b) Connect the power supply. Adjust the variable current control until approximately 5 A is registered on the ammeter.
(to be continued)
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APPENDIX A (continued)
c) Read the voltage difference as indicated by the millivoltmeter.
d) Calculate the anode-to-core resistance (R), in ohms, using the following equation:
R = amperes)(in readingammeter (in volts) readingeter millivoltm
e) Reverse both ammeter supply leads and also the millivoltmeter supply leads, and repeat Steps (a) to (d) above. The result of this second calculation of R should be the same as the initial result.
A.6 Report
The test report shall contain the following information:
a) Name of test laboratory.
b) Identification of the equipment used to carry out the test.
c) Identification of the galvanic anode tested.
d) The date on which the test was carried out.
e) The results of the anode-to-core resistance test calculations.
f) Reference to this test method.
(to be continued)
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APPENDIX A (continued)
b) With cable attached
SCHEMATIC CIRCUITS FOR MEASUREMENT OF ANODE-TO-CORE RESISTANCE
Fig. A.1
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APPENDIX B
METHOD FOR THE DETERMINATION OF THE CONSUMPTION RATE
OF ALUMINUM ANODE ALLOYS IMMERSED IN SEAWATER
B.1 General
This Appendix describes the method for the determination of the consumption rate of aluminum anode alloys intended for use in cathodic protection of ferrous metals immersed in seawater.
Note:
The anode alloy consumption rate, expressed in kilograms per ampere year, is an important factor when the performance of different alloys for the sacrificial protection of ferrous metal structures in seawater is being assessed. The consumption rate may be used to compute the current capacity of an anode system.
B.2 Principle
The loss of anode mass, which occurs when a known quantity of current flows from the anode to the cathode in seawater, is computed to show the quantity of anode metal consumed in one year by the passage of 1 A.
B.3 Apparatus
The following apparatus is required:
a) A constant current d.c. power supply with an output voltage appropriate to the number of test cells in series, and having sufficient current capacity to maintain the specified anode current density. The output current stability of the power supply shall be within ±1%.
b) An ammeter to suit the current requirement, and having a maximum error of ±1%. This ammeter may be integral with the power supply (see Item (a)).
c) Aluminum cathodes; one per aluminum anode.
d) Non-metallic tanks; one per anode, to hold seawater.
e) Clean seawater with a resistivity of not greater than 0.3Ω .m at 20°C, or synthetic seawater conforming to the requirements of ASTM D 1141.
f) An agitator.
B.4 Circuit
The circuit shall be arranged as shown in Fig. B.1.
B.5 Preparation of Test Anodes
The as-manufactured anode surface is preferred for test purposes, however cut and machined surfaces are not excluded for use in this test. All anodes used in the same test series shall have the same nominal composition and the same area dimensions exposed to seawater.
Any mounting strap or wiring conductor shall be covered to prevent contact with seawater.
(to be continued)
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APPENDIX B (continued)
The anodes shall be cleaned in nitric acid (e20 1420 kg/m³) at ambient temperature and then thoroughly rinsed in clean fresh water and dried.
B.6 Procedure
The anode consumption rate shall be determined as follows:
a) Weight each anode and record its mass.
b) Connect the circuit as shown in Fig. B.1.
c) Adjust the power supply to produce a current output equivalent to a current density of between 0.5 mA/cm² and 0.7 mA/cm² of anode surface area. Note the time of commencement of the test and the set current value.
d) Change the seawater when 0.1 A.h has passed for each 1 L of seawater in a cell.
e) Continue the test for a period of at least 10 days.
Note:
The longer the test period the more reliable will be the result.
f) Remove the test anodes from the cells. Clean, rinse and dry the test anodes in accordance with Paragraph B.5, and reweight.
g) Calculate the alloy consumption rate for each anode, in kilograms per ampere year, using the following equation:
Alloy consumption rate = flowcurrent total8760 loss mass×
Where:
mass loss is in kilograms;
total current flow is in ampere hours.
Express the result to the nearest 0.1 kg/A. year.
(to be continued)
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APPENDIX B (continued)
Legend:
C = cathode
A = anode
SCHEMATIC CIRCUIT FOR DETERMINATION OF ALLOY CONSUMPTION RATE
Fig. B.1
B.7 Report
The report shall contain the following information:
a) Name of the test laboratory.
b) Identification of the equipment used to carry out the test.
c) Identification of the anode material.
d) The mass of each anode before and after completion of the test.
e) Other test details including the test period.
f) The dates during which the test was carried out.
g) The test results.
h) Reference to this test method.
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APPENDIX C
METHOD FOR THE DETERMINATION OF THE CLOSED-CIRCUIT
POTENTIAL OF ALUMINUM ANODES IMMERSED IN SEAWATER
C.1 General
This Appendix describes the method for the determination of the closed-circuit potential of aluminum anodes intended for use in the cathodic protection of ferrous metals immersed in seawater.
Note:
The closed-circuit potential, as distinct from the open-circuit potential, is a critical factor when assessing the ability of galvanic anodes to protect ferrous metal structures in service.
C.2 Principle
The closed-circuit potential is measured when current is flowing between an anode and cathode in seawater, by locating a reference cell close to the anode surface.
C.3 Apparatus
The following apparatus is required:
a) A 12 V d.c. power source with a variable resistance to maintain the specified anode current density.
b) A suitable ammeter.
c) A high resistance voltmeter with a minimum input resistance of 1 MΩ/V and a resolution of 10 mV or better, and having a maximum error of ±1% at full scale deflection.
d) A silver/silver chloride or saturated calomel reference electrode.
e) An aluminum cathode.
f) A non-metallic tank to hold seawater.
g) Fixed resistors of equal value. The voltage drop across each fixed resistor shall be at least 10 V.
h) Clean seawater with a resistivity of not greater than 0.3Ω .m at 20°C, or synthetic seawater conforming to the requirements of ASTM D 1141.
C.4 Circuit
The circuit shall be arranged as shown in Fig. C.1 to enable the testing of one of a series of anodes. All anodes in the circuit shall have the same nominal composition and shape and the same area dimensions exposed to the seawater.
Any mounting, wiring conductor or anode connection shall be insulated at the air/water interface to prevent contact with seawater.
C.5 Preparation of Test Anode
For test purposes, it is preferred that the surface of the anode is in the as-manufactured condition, however cut and machined surfaces are also acceptable.
(to be continued)
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APPENDIX C (continued)
C.6 Procedure
The closed-circuit potential shall be determined using the following procedure:
a) Arrange the equipment so that the anode-to-cathode distances are approximately the same, and the current flow is not affected by cell geometry or adjacent anodes.
b) Adjust the test anode current density to a value between 0.5 mA/cm² and 0.7 mA/cm² and record the time of commencement of current flow. Change the seawater when 0.1 A.h has passed for each litre of seawater contained in the tank.
c) Record, to the nearest 0.01 V, the closed-circuit potential on the voltmeter. Continue the test until three consecutive stable readings are obtained at time intervals of 1 h.
d) Report the last three stable closed-circuit potential readings obtained with respect to the reference cell, for the anode under test.
e) Repeat Steps (a) to (d) for each anode tested to enable duplication of the results.
C.7 Report
The report shall contain the following information:
a) Name of the test laboratory.
b) Identification of the equipment used to carry out the test, the reference cell, details of the circuit and details of the seawater used.
c) Identification of the anode material, and number and dimensions of anodes in the circuit.
d) The current density used, test procedure details and resultant closed circuit potential readings (in duplicate).
e) The date of testing.
f) Reference to this test method.
SCHEMATIC CIRCUIT FOR MEASUREMENT OF CLOSED-CIRCUIT POTENTIAL
Fig. C.1
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APPENDIX D
DATA SHEET
(TO BE SUBMITTED BY THE PURCHASER)
FOR
IPS-M-TP-750: Part 5 BRACELET GALVANIC ANODES
The anodes shall be in accordance with the latest edition of above Iranian Petroleum Standard with the following specific requirements:
- Project title: ............................................ - Date: .........................................
- Indent No.: ............................................. - Purchaser:..................................
- M.E.S.C. No.: ........................................ - No. of Anodes: .........................
- Project title: - Date:
- Type of Anode: b Aluminum Anode b Zinc Anode
- Anode Shape: b Plain Half-Shell
b Tapered Half-Shell
- Anode lead wire insulation: b Single Jacket HMWPE
b Single Jacket XLPE
b Double Jacket PVC/PVC
- Pipe O.D.:
- Pipe coating: Type:
Thickness:
- Antiflotation coating: Type:
Thickness:
- Environmental conditions:
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PART 6
CAST GALVANIC ANODES
FOR
FIXED OFFSHORE INSTALLATIONS
(ALUMINUM)
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CONTENTS : PAGE No.
1. SCOPE.........................................................................................................................................84
2. REFERENCES.............................................................................................................................84
3. DEFINITIONS AND TERMINOLOGY...........................................................................................84
4. UNITS...........................................................................................................................................87
5. TECHNICAL DOCUMENTS.........................................................................................................87
6. MATERIALS AND MANUFACTURE............................................................................................88
7. REQUIREMENTS.........................................................................................................................91
8. INSPECTION AND TESTING.......................................................................................................93
9. ACCEPTANCE/REJECTION........................................................................................................94
10. SUPPLIED DOCUMENTATION.................................................................................................94
11. INFORMATION TO BE SUPPLIED BY THE PURCHASER......................................................94
12. PACKING AND SHIPMENT.......................................................................................................95
13. MARKING..................................................................................................................................95
APPENDICES:
APPENDIX A METHOD FOR THE DETERMINATION OF THE ANODE-TO-CORE RESISTANCE OF GALVANIC ANODES.................................................................................................................96
APPENDIX B METHOD FOR THE DETERMINATION OF THE CONSUMPTION RATE OF ALUMINUM ANODE ALLOYS IMMERSED IN SEAWATER..........................................................98
APPENDIX C METHOD FOR THE DETERMINATION OF THE CLOSED-CIRCUIT POTENTIAL OF ALUMINUM ANODES IMMERSED IN SEAWATER................................................................101
APPENDIX D TYPICAL MASSES AND DIMENSIONS OF PLATFORM ALUMINUM ANODES.103
APPENDIX E ALUMINUM ANODES TYPICAL FIXING ARRANGEMENTS................................104
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1. SCOPE
This Part of IPS-M-TP-750 covers the minimum requirements for the material, manufacture, inspection and testing of cast sacrificial anodes made of Aluminum-zinc-indium, intended for use on fixed offshore installations.
This Standard specification covers only the general requirements for the aluminum anodes, the specific requirements will be given in pertinent ordering documents.
2. REFERENCES
Throughout this Standard the following dated and undated standards/codes are referred to. These referenced documents shall, to the extent specified herein, form a part of this standard. For dated references, the edition cited applies. The applicability of changes in dated references that occur after the cited date shall be mutually agreed upon by the Company and the Vendor. For undated references, the latest edition of the referenced documents (including any supplements and amendments) applies.
API (AMERICAN PETROLEUM INSTITUTE)
API 5L "Specification for Linepipe"
ASTM(AMERICAN SOCIETY FOR TESTING AND MATERIALS)
B660M Standard Practice for "Packaging/Packing of Aluminum and Magnesium Products"
D1141 "Substitute Ocean Water"
E101 Standard Test Method for
"Spectrographic Analysis of Aluminum and Aluminum Alloys by the Point-to-Plane Technique"
E716 Standard Practice for
"Sampling Aluminum and Aluminum Alloys for Spectrochemical Analysis"
BSI (BRITISH STANDARDS INSTITUTION)
BS EN
10 204 "Metallic Products-Types of Inspection Documents"
ISO (INTERNATIONAL ORGANIZATION FOR STANDARDIZATION)
8501-1 "Preparation of Steel Structures Before Application of Paints and Related Products-Visual Assessment of Surface Cleanlines"
3. DEFINITIONS AND TERMINOLOGY
For the purpose of this Standard, the definitions below apply:
Anode consumption rate
The rate of alloy mass consumption for a given current output over a given period; normally stated in kilograms per ampere year.
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Cast sacrificial anode
The negative (reactive) component of a galvanic cell, designed to oxidize sacrificially and produce direct electrical current to protect a more electropositive (noble) metal operating in the same electrolyte and produced to a desired shape by the solidification of a molten alloy in a mold or die.
Certificate of conformity
A statement made by the producer’s representative (executive) and endorsed by a representative of the customer that the anodes listed comply with the requirements of the order.
Cold lap
Horizontal discontinuity caused by solidification of the meniscus of a partially cast anode as a result of interrupted flow of the casting stream. The solidified meniscus is covered with metal when the flow resumes. Cold laps can occur along the length of an anode.
Closed circuit potential
The potential of an anode connected to a structure when passing current; normally measured against a reference electrode in a particular environment.
Cold shut
Horizontal surface discontinuity caused by solidification of a portion of a meniscus during the progressive filling of a mold, which is later covered with more solidifying metal as the molten metal level rises. Cold shuts generally occur at corners remote from the point of pour.
Cracking
Fracture of metal along an irregular path producing a discontinuity similar to a ragged edge. It can occur during the solidification of the anode (hot cracking), during the contraction of the anode after solidification, or under externally applied loads. Hot cracking may be associated with the shrinkage depression that can occur in open-topped molds.
Current capacity
The total current flow available from an anode of given mass of alloy; normally expressed as ampere years per kilogram. This is the inverse of the anode consumption rate.
Current density
The average amount of current entering or leaving a given surface area.
Dulling of steel
Deterioration in appearance of shot-blasted inserts because of oxidation that causes darkening of the surface but not rust discoloration (see Rust Discoloration).
Electrochemical properties
Those properties of potential and current capacity that characterize a sacrificial anode and can be assessed by quantitative tests.
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Gas holes
The evidence of bubbles within the solidifying metal. The holes can indicate that moisture was on the mold or insert prior to casting, or that the liquid metal contained a high level of hydrogen that had been thrown out of solution to form bubbles during the cooling of the metal.
Gross anode mass
Total mass of an anode, including anode core.
Heat
Also called a "melt" or "cast", it is the unit that defines molten metal and identifies the anodes cast from it. A heat is the product that is cast to a planned procedure in one melting operation in one furnace, without significant interruption. If the casting sequence is interrupted, the anodes produced before, between, and after the interruptions constitute "batches".
Inserts
The form over which the anode is cast and which is used to connect the anode to the structure requiring protection. These are sometimes referred to as "cores".
Low carbon steels
Steels having less than 0.30% carbon and no intentional alloying additions.
Net anode mass
Mass of actual anode alloy.
Nonmetallic inclusions
Particles of oxides and other refractory materials entrapped in liquid metal during the melting or casting sequences.
Open circuit potential
The potential of an anode when not connected to a structure; normally measured against a reference electrode in a particular environment.
Porosity
Generally distributed fine holes caused by gas bubbles, shrinkage (formed by the starvation of eutectic material within the dendrite arms during "unfed" solidification), or a combination of the two mechanisms when hydrogen in solution diffuses into the lower pressure shrinkage voids.
Protrusion
Extraneous material on the anode surface. It may interfere with the anode-to-structure fit, appear unattractive, and be a safety hazard if there are sharp edges. Protrusions can be formed by careless filling of the mold or the flash from imperfect fitting of mold sections.
Reference electrode
An electrode which has a stable potential in one or more electrolytes, thus enabling it to be used for the measurement of other electrode potentials at a given temperature.
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Rimming (rimmed) steels
An incompletely deoxidized steel. (See ASM Metals Handbook, 7th. Edition for exhaustive definition.)
Rust discoloration
A brown bloom of iron oxide.
Sample
A representative specimen.
Shrinkage depression
The natural concave surface produced when liquid metal is allowed to solidify in a container without the provision of extra liquid metal to compensate for the reduction in volume that occurs during the liquid-solid transformation. The term also applies to the concave surface produced when liquid metal is solidified in a closed mold in such a manner that the area is not "fed" by the liquid metal provided by the casting’s riser.
Tap sample
A specimen taken from a molten metal stream. Such samples may be taken at the commencement of pouring and then at regular intervals until a final sample is taken at the end of the pour.
Voids adjacent to insert
Visible spaces between anode and insert materials. These can be caused by surface evaporation of moisture from the insert, contraction of the insert, or movement of the insert during casting caused by uneven heating and expansion that distorts the insert and prevents it from returning to its original, desired position within the anode.
4. UNITS
This Standard is based on International System of Units (SI), except where otherwise specified.
5. TECHNICAL DOCUMENTS
The Vendor shall provide full documentation on the following:
a) Manufacturing drawings for anodes: including dimensions, tolerances, steel, grade, alloy type and weights.
b) Production procedures that cover all stages of the manufacturing process, from receipt of raw materials to finishing and packing for shipment, including:
- chemical analysis;
- surface preparation;
- measurements of weights, dimensions, bowing, twisting, crack size, etc.;
- inspection and testing procedures, including acceptance criteria, and frequencies;
- anode manufacture;
- identification of rejected anodes.
c) Insert bending, welding and preparation procedures: including acceptance limits for wall
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thinning and ovality, non-destructive testing procedures, surface profile measurements.
d) Electrochemical test procedures, including acceptance criteria, description of test apparatus, measurement methods and preparation and cleaning of samples.
e) Preservation, packing and shipping procedures, such that anodes are not damaged or deformed and do not deteriorate during handling, delivery to the fabrication yard, storage: including methods, materials and any requirement for periodic inspections.
Any certificates issued by an inspection agency shall be included in the documentation.
6. MATERIALS AND MANUFACTURE
6.1 General
6.1.1 The electrochemical properties are highly dependent on the content of alloying elements and impurity elements. The anode manufacturer shall thus prove his capability of delivering anodes which satisfy this Part of Standard specification.
6.1.2 Small deviations from the specification in the alloy composition may significantly reduce the protective properties. Generally it is of importance that the fabrication procedure ensures that the melt is not polluted by iron or other impurities. Furnaces, pumps, pipes, etc., shall be non-metallic or properly lined.
6.1.3 The quality control at the anode manufacturing plant shall include control systems on the following:
- Raw materials, i.e., checking of documentation.
- Production equipment and process.
- Testing during and after production.
- Identification of anodes.
- Chemical analysis.
- Weight and dimensional tolerances.
- Surface condition of produced anodes.
- Documentation (material certificates).
6.2 Type of Anodes
6.2.1 The anodes shall be of the "stand-off" type, cast in Aluminum-Zinc-Indium sacrificial alloy, with a minimum stand-off distance of 150 mm, and can have a trapezoid or cylindrical shape.
6.2.2 The alloy shall be proven to be free from passivity and intergranular corrosion for the conditions specified in ordering/purchasing documents.
6.2.3 The anodes shall be sufficiently rigid to avoid vibration in the anode support.
6.3 Chemical Composition
The anodes shall conform to the chemical composition specified in Table 1 as determined by spectrographic and other methods specified herein.
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TABLE 1 - CHEMICAL COMPOSITION LIMITS a)
ELEMENT
COMPOSITION, %
BY WEIGHT
Silicon, max
Iron, max
Copper, max
Zinc
Indium
Other elements, each, max
Other elements, total b), max
Aluminum
0.10
0.10
0.006
3.0 - 5.0
0.02 - 0.05
0.02
0.05
Remainder c)
a) Analysis shall regularly be made only for the elements specified in this table. If, however, the presence of other elements is suspected or indicated in amounts greater than the specified limits, further analysis shall be made to determine that these elements are not present in amounts in excess of the specified limits.
b) Other Elements - Total shall be the sum of unspecified metallic elements 0.010% or more, rounded to the second decimal before determining the sum.
c) The aluminum content shall be calculated by subtracting from 100.00%.
6.4 Production Testing
The manufacturer shall carry out the following production testing:
6.4.1 Chemical analysis
6.4.1.1 Two samples from each melt shall be taken for chemical analysis. The samples shall be taken in the beginning and at the end of casting from the pouring string.
For smaller alloying furnaces (approx. 500 kg) it is sufficient to take one sample per batch. The sample shall be taken at the beginning of one batch, at the end of the next and so on.
Sampling shall be in accordance with ASTM Practice E716 or approved alternative standard.
6.4.1.2 Analysis shall be by spectrographic analysis in accordance with ASTM Test Method E 101 or approved alternative standard, in case of dispute, the methods of analysis shall be agreed upon by the Purchaser and supplier.
6.4.1.3 If one of these analysis is out of the specified range, the heat will be rejected. Individual anodes may be accepted subject to further analysis, at the option of the Purchaser.
6.4.2 Electrochemical testing for quality control
6.4.2.1 Checking of closed-circuit-potential and current capacity shall be done for each 10 ton produced anodes, with minimum one test per order. The test samples may be separately casted or cut directly from an anode.
6.4.2.2 The testing shall preferably be carried out by a body independent of the manufacturer.
6.4.2.3 The methods of testing should be in accordance with Appendices B and C.
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6.4.3 Destructive and non-destructive testing
6.4.3.1 At least one anode per delivery or at least 0.5% of the anodes, where net weight of the anode exceeds 100 kg, shall be subject to destructive testing to check the bonding between anode material and steel core in cross-sectional areas.
6.4.3.2 All sectioning shall be carried out in the presence of purchaser’s inspector(s).
6.4.3.3 Anodes shall be sectioned transversely, by single cuts, at 25%, 33% and 50% of nominal cast length.
6.4.3.4 Anodes shall be sectioned once longitudinally through the center line/pour point.
6.4.3.5 Not more than 5% of the insert peripheral length in any sectioned surface shall show visible lack of bond between the insert and the cast alloy.
6.4.3.6 There shall be no visible pores and slag/dross inclusions in any sectioned surface.
6.4.3.7 Total porosity in any sectioned surface shall not exceed 0.25% of the alloy area, with no individual pores or voids greater than 10 mm².
6.4.3.8 Should any anode section fail to meet the above criteria, the subsequent anode cast shall also be sectioned. If this also fails, the entire production batch (since the last successful section) shall be quarantined and a series of backchecks made in order to allow acceptance of part batches. Acceptance of quarantined anodes shall be at the sole discretion of Purchaser’s inspector(s). The problem shall be investigated, and the cause corrected to Purchaser’s inspector satisfaction, before production continues.
6.4.3.9 Alternatively to destructive testing a non-destructive testing by radiography may be used to check for lack of bond or slag/dross inclusions.
6.5 Anode Insert
6.5.1 Insert material
6.5.1.1 The platform anode insert shall be cut from unspliced weldable seamless low alloy carbon steel line pipe to API 5L, Grade B or approved equivalent standard.
6.5.1.2 The steel inserts shall have sufficient strength to withstand all external forces that they may normally encounter.
6.5.1.3 The carbon equivalent (Cev) of the insert materials shall not exceed 0.45 percent, determined using the following formula:
Cev = C +6Mn +5VMoCr++ + 15CuNi+
Where each element is expressed in weight percent.
6.5.1.4 Rimming steels shall not be used.
6.5.1.5 Mill certificates shall conform to the requirements of BS EN 10 204, Part 3.1.B, and shall be obtained for all steel used in the manufacture of inserts.
6.5.1.6 For low temperature applications, consideration shall be given to the notch toughness of material; in particular, to the toughness of the material to be welded to the parent structure.
6.5.2 Insert surface preparation
6.5.2.1 All anode inserts shall be blast cleaned to ISO 8501-1, Grade SA 2½ prior to anode casting.
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Sand shall not be used for blast cleaning. The surface profile of the cleaned surface shall be 50 to 100 microns.
6.5.2.2 Inserts shall be stored indoors at a humidity not exceeding 85% and such that the steel temperature is maintained at least 3°C above the dew point.
6.5.2.3 Inserts not used within 8 hours of blast cleaning, or any which show signs of rusting or surface contamination, or which do not conform to ISO 8501-1 Grade SA 2½ at time of casting, shall be re-cleaned in accordance with the requirements of 6.5.2.1.
6.5.2.4 At the time the anodes are cast, "dulling" of the blast cleaned surface of the insert shall be permitted. Rust discoloration and/or visible surface contamination shall not be permitted.
6.5.3 Insert fabrication
6.5.3.1 All fabrication welding and acceptance tests on anode insert shall be in accordance with AWS D1.1 latest edition, or approved equivalent standard.
Welding procedures and welder qualifications shall be in accordance with AWS D1.1, latest edition, or approved equivalent standard.
6.5.3.2 All welds shall be visually inspected and be free of deleterious defects. Adequate examination of production welds shall be carried out by appropriate non-destructive testing.
6.5.3.3 Tubular inserts shall be bent using purpose-built equipment. The manufacturer shall confirm that the bend radii given on the contract drawings are suitable. Surface cracking and wrinkling on the inside surface of the bend shall not be acceptable.
6.5.3.4 The manufacturer shall ensure that the necessary controls are placed on the heat treatment condition, and other relevant parameters, of the tube material so as to permit satisfactory bending of inserts.
6.5.3.5 Where inserts are pre-heated prior to pouring of aluminum alloy, the manufacturer shall provide appropriate control and measurement of the insert temperature and shall ensure that the specified standard of cleanliness is maintained.
6.5.3.6 Inserts shall be held rigidly during casting.
6.5.4 Insert position
The position of the insert in the platform anode casting shall be within 5 mm of the design position as an average over the anode length and not more than 10 mm from the design position at any point.
7. REQUIREMENTS
7.1 Casting Quality
7.1.1 Each anode shall be cast in one pour. Intermediate solidification’s are not acceptable. Cold shuts or surface laps shall not be permitted.
7.1.2 Anodes shall be topped up prior to final solidification to present a top cast surface free from shrinkage cavities and depressions. Overpouring after solidification shall not be permitted.
7.1.3 No grinding or other surface treatment shall be permitted except that which shall be carried out to remove mould flashing or other protrusions that might present a safety hazard.
7.1.4 All protrusions detrimental to the safety of personnel during handling shall be removed.
7.1.5 The anode surface shall be free from cracks which may reduce the performance of the anode.
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7.1.6 Any cracks which follow the longitudinal direction of anodes are not acceptable.
7.1.7 Smaller cracks in the transverse direction may be acceptable provided the cracks would not cause any mechanical failure during service of the anode. The combination of cracks and lack of bond to the anode core is detrimental.
For transverse cracks, the following limits should be used:
- Cracks with a length of less than 50 mm and width less than 5 mm are normally acceptable.
- Cracks with a length of 50 - 200 mm should be limited to 2 per anode face or 4 per anode.
- Cracks with a length of more than 200 mm or which are more than 5 mm in width are not acceptable.
7.1.8 The anode surface shall be free from any significant slag/dross inclusions or anything that may be considered detrimental to the satisfactory performance of the anodes. There shall be no visible disbondment from the insert surface.
7.1.9 Shrinkage depressions shall not exceed 100 mm in length, 12 mm in width and 10 mm depth.
7.1.10 Casting surface irregularities shall be fully bonded to the bulk anodic material.
7.1.11 Not more than 1% of the total surface of the anode casting shall be contaminated with non metallic inclusions visible to the naked eye.
7.1.12 Reduction in cross section of anodic material adjacent to the emergence of inserts shall not exceed 10% of the nominal anode cross section.
7.1.13 Anode inserts protruding from the anodes shall be smooth and free of sharp edges.
7.2 Weight and Dimensional Tolerances
7.2.1 The weight tolerance on individual anodes shall be within ±3% of the specified net weight.
7.2.2 The total contract weight shall be no more than 2% above and not below the nominal contract weight.
7.2.3 Dimensional tolerances shall conform to the following:
- Diameter of cylindrical anodes: ± 7.5
- Width : ± 5%
- Depth : ± 10%
- Length (for anodes > 1 m long): ± 25 mm
(for shorter anodes): ± 2.5%
7.2.4 The straightness of the anode shall not deviate more than 2% of the anode nominal length from the longitudinal axis of the anode.
7.2.5 The anode insert location within stand-off anodes shall at least be within ±5% of the nominal position in anode width and length and within 10% of the nominal position in anode depth.
7.2.6 Anode insert cross section dimensions shall comply with the appropriate specification for the insert material used.
7.3 Performance Requirements
7.3.1 Mechanical resistance
When an uniaxial force equivalent to 100 kg, or five times the mass of the anode metal, whichever is the greater, is applied to a cast anode containing a core, no movement of the core or any metal
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insert shall occur.
7.3.2 Electrical resistance
When determined in accordance with the test method in Appendix A, the electrical resistance of the anode to core shall not be greater than 0.01 Ω for the life of the anode.
7.3.3 Consumption rate in seawater
When determined in accordance with the test method in Appendix B, the consumption rate of an aluminum anode in seawater shall not exceed 3.5 kg/A year.
7.3.4 Closed circuit potential in seawater
When determined in accordance with Appendix C, the closed-circuit potential of an aluminum anode shall be at least -1.05 V with respect to a silver/silver chloride reference electrode.
7.4 Identification of Anodes
Each anode shall be clearly marked with the type of material (trade name), the cast number, and a piece of serial number. The numbers of any rejected anodes shall not be used again for replacement anodes.
7.5 Anode Protection
Before storage outside, the open ends of the platform anode inserts shall be sealed against water ingress by the use of non-metallic end caps.
The supplier shall notify purchaser of any extra requirements to be carried out in order to prevent deterioration of the anodes and inserts.
8. INSPECTION AND TESTING
8.1 Responsibility for Inspection and Tests
8.1.1 Unless otherwise specified, the manufacturer and/or supplier shall be responsible for carrying out all the tests and inspections required by this Part of Standard specification using his own or other reliable facilities, and he shall maintain complete records of all such tests and inspections. Such records shall be available for review by the Purchaser.
8.1.2 The manufacturer and/or supplier shall afford the Purchaser’s inspector all reasonable facilities necessary to satisfy him that the material is being produced and furnished in accordance with this Part of Standard specification.
8.1.3 The Purchaser reserves the right to perform any inspections set forth in the specification where such inspections are deemed necessary to assure that supplies and services conform to the prescribed requirements.
8.1.4 The Purchaser’s inspector shall have access to the material subject to inspection for the purpose of witnessing the selection of the samples, the preparation of the test pieces, and the performance of the test(s). For such tests, the inspector shall have the right to indicate the pieces from which the samples will be taken in accordance with the provisions of this Part of Standard specification.
8.1.5 The manufacturer shall inspect the material covered by this Part of Standard specification prior to shipment and shall furnish to the Purchaser a certificate of inspection stating that each lot
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has been sampled, tested, and inspected in accordance with this Part of Standard specification and has been found to meet the requirements specified.
8.1.6 If the Purchaser desires that his representative inspect or witness the inspection and testing of the product prior to shipment, the producer or supplier shall afford the Purchaser’s representative all reasonable facilities to satisfy him that the product meets the requirements of this Part of Standard specification. Such inspections in no way relieve the supplier/ manufacturer of his responsibilities under the term of this Part of Standard specification.
8.2 Inspection
Inspection shall cover the following as a minimum:
8.2.1 Dimensional checking, identification, weight, and quality of castings on at least 5% of the number of anodes from each cast.
8.2.2 Quality of steel inserts before casting, and surface preparation on at least 5% of inserts for the batch of anodes from each cast.
8.2.3 Quality of steel-anode bonding on the anode from each order, selected for destructive testing.
8.2.4 Inspection of results of spectro analysis, voltage tests, capacity tests, and destructive testing done by manufacturer.
9. ACCEPTANCE/REJECTION
9.1 Acceptance/rejection of anodes will be on a total inspection of all anodes.
9.2 Where any of the requirements, mentioned in this Part of Standard specification, are not met, the anodes and the relevant batch of anodes will be rejected.
10. SUPPLIED DOCUMENTATION
The following documentation shall be supplied with each anode batch:
- The anode batch and cast numbers.
- Details of anode casting weights (net and gross) and numbers.
- Steel core mill certification.
- Results of any destructive testing.
- Results of any non-destructive testing.
- Electrochemical test results.
- Anode alloy chemical analysis results.
- Material specification and trade name.
- The anode manufacturer.
- The Company’s Order No.
- The date of manufacture
- Certificate of conformity with this Part of Standard specification.
11. INFORMATION TO BE SUPPLIED BY THE PURCHASER
The Purchaser shall supply the following information at the time of enquiry:
a) Title, number, and date of this Part of Standard specification.
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