RECOMMENDED PRACTICE
D ET N ORSK
E V
ERITAS DNV-RP-B401
CATHODIC PROTECTION DESIGN
OCTOBER 2010
This document has been amended since the main revision (October 2010), most recently in April 2011.
See “Changes” on page 3.
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FOREWORD向昨天告别
DET NORSKE VERITAS (DNV) is an autonomous and independent foundation with the objectives of safeguarding life,property and the environment, at a and onshore. DNV undertakes classification, certification, and other verification and consultancy rvices relating to quality of ships, offshore units and installations, and onshore industries worldwide, and carries out rearch in relation to the functions.
DNV rvice documents consist of amongst other the following types of documents:
—Service Specifications. Procedual requirements.
—Standards. Technical requirements.
—Recommended Practices. Guidance.
The Standards and Recommended Practices are offered within the following areas:
A)Qualification, Quality and Safety Methodology
校园记者
B)Materials Technology
C)Structures
D)Systems
E)Special Facilities
F)Pipelines and Rirs
G)Ast Operation
H)Marine Operations
J)Cleaner Energy
O)Suba Systems
Amended April 2011Recommended Practice DNV-RP-B401, October 2010 e note on front cover Changes – Page 3 CHANGES
•General
As of October 2010 all DNV rvice documents are primarily published electronically.智力低下表现
In order to ensure a practical transition from the “print” scheme to the “electronic” scheme, all documents having incorporated amendments and corrections more recent than the date of the latest printed issue, have been given the date October 2010.
An overview of DNV rvice documents, their update status and historical “amendments and corrections” may be found through /resources/rules_standards/.
•Main changes October 2010
Since the previous edition (January 2005), this document has been amended, most recently in April 2008. All changes have been incorporated and a new date (October 2010) has been given as explained under “General”.
•Amendments April 2011
—Item 6.5.2 has been amended and clarified concerning galvanic anode performance requirements.
—A new Guidance note has been added to item 12.4.4 (Annex C).
—The layout has been changed to one column in order to improve electronic readability.
Recommended Practice DNV-RP-B401, October 2010Amended April 2011 Page 4 – Contents e note on front cover
CONTENTS
1.GENERAL (6)
1.1Introduction (6)
1.2Scope (6)
1.3Objectives and U (7)
1.4Document Structure (7)
1.5Relation to Other DNV Documents (7)白蛇与许仙
2.REFERENCES (7)
2.1General (7)
2.2ASTM (American Society for Testing and Materials) (7)
2.3DNV (Det Norske Veritas) (7)
2.4EN (European Standards) (7)
2.5NORSOK (7)
建华学校
2.6ISO (International Organization for Standardisation) (7)
2.7NACE International (8)
3.TERMINOLOGY AND DEFINITIONS (8)
3.1Terminology (8)
3.2Definitions (8)
4.ABBREVIATIONS AND SYMBOLS (9)
4.1Abbreviations (9)
4.2Symbols (9)
5.GENERAL CP DESIGN CONSIDERATIONS (INFORMATIVE) (10)
5.1General (10)
5.2Limitations of CP (10)
5.3Environmental Parameters Affecting CP (10)
5.4Protective Potentials (11)
5.5Detrimental effects of CP (11)
5.6Galvanic Anode Materials (12)
5.7Anode Geometry and Fastening Devices (13)
5.8U of Coatings in Combination with CP (13)
5.9Electrical Continuity and Current Drain (13)牛排用英语怎么说
6.CP DESIGN PARAMETERS (14)
6.1General (14)
6.2Design Life (14)
6.3Design Current Densities (14)
星期拼音6.4Coating Breakdown Factors for CP Design (16)
6.5Galvanic Anode Material Design Parameters (17)
6.6Anode Resistance Formulas (18)
6.7Seawater and Sediment Resistivity (18)
6.8Anode Utilization Factor (18)
6.9Current Drain Design Parameters (18)
7.CP CALCULATION AND DESIGN PROCEDURES (19)
7.1General (19)
7.2Subdivision of CP Object (20)
7.3Surface Area Calculations (20)
Amended April 2011Recommended Practice DNV-RP-B401, October 2010 e note on front cover Contents – Page 5
7.4Current Demand Calculations (20)
7.5Current Drain Calculations (20)
7.6Selection of Anode Type (21)
7.7Anode Mass Calculations (21)
7.8Calculation of Number of Anodes (21)
7.9Calculation of Anode Resistance (22)
7.10Anode Design (23)
7.11Distribution of Anodes (23)
7.12Provisions for Electrical Continuity (23)
7.13Documentation (24)
8.ANODE MANUFACTURE (24)
8.1General (24)
8.2Manufacturing Procedure Specification (25)
8.3Pre-Production Qualification Testing (25)
8.4Quality Control of Production (26)
8.5Materials, Fabrication of Anode Inrts and Casting of Anodes (26)
8.6Inspection and Testing of Anodes (27)
8.7Documentation and Marking (28)
8.8Handling, Storage and Shipping of Anodes (28)
9.INSTALLATION OF ANODES (28)
9.1General (28)
惹人喜爱的近义词9.2Installation Procedure Specification (28)
9.3Qualification of installation (29)
9.4Receipt and Handling of Anodes (29)
9.5Anode Installation and Provisions for Electrical Continuity (29)
9.6Inspection of Anode Installation (29)
9.7Documentation (29)
10.ANNEX A – TABLES AND FIGURES (30)
10.1Tables and Figures (30)
11.ANNEX B – LABORATORY TESTING OF GALVANIC ANODE MATERIALS
FOR QUALITY CONTROL (33)
11.1General (33)
11.2Sampling and Preparation of Test Specimens (33)
11.3Equipment and Experimental Procedure (33)
11.4Acceptance Criteria and Re-Testing (34)
11.5Documentation (34)
12.ANNEX C – LABORATORY TESTING OF GALVANIC ANODE MATERIALS
FOR QUALIFICATION OF ELECTROCHEMICAL PERFORMANCE (36)
12.1General (36)
12.2Sampling and Preparation of Test Specimens (36)
12.3Equipment and Experimental Procedure (36)
12.4Documentation (37)
