1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN 16299:2013Cathodic protection of externalsurfaces of above groundstorage tank bases in contactwith soil or foundationsBS EN 16299:2013 BRITISH STANDARDNational forewordThis
2、 British Standard is the UK implementation of EN 16299:2013. The UK participation in its preparation was entrusted to T e c h n i c a l Committee GEL/603, Cathodic protection.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not p
3、urport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2013. Published by BSI Standards Limited 2013.ISBN 978 0 580 72888 4 ICS 77.060 Compliance with a British Standard cannot confer immunityfrom legal oblig
4、ations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2013.Amendments issued since publicationDate T e x t a f f e c t e dBS EN 16299:2013EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 16299 April 2013 ICS 77.060 English Versi
5、on Cathodic protection of external surfaces of above ground storage tank bases in contact with soil or foundations Protection cathodique des surfaces externes des fonds de rservoirs de stockage ariens en contact avec le sol ou les fondations Kathodischer Korrosionsschutz fr erdberhrte und gegrndete
6、Auenflchen von oberirdischen Lagertanks aus Stahl This European Standard was approved by CEN on 23 February 2013. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any a
7、lteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language
8、made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Es
9、tonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR ST
10、ANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2013 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 16299:2013: EBS EN 16299:2013EN 16299:2013 (E) 2
11、Contents Page Foreword . 4 Introduction 5 1 Scope 6 2 Normative references . 6 3 Terms and definitions 7 4 Abbreviations and symbols . 8 5 Competence of personnel 8 6 Corrosion risks and their prevention by cathodic protection 9 6.1 General . 9 6.2 Corrosion risks of external surfaces of above groun
12、d storage tank bottoms in contact with soil or foundations . 9 7 Pre-requisites for the application of cathodic protection . 12 7.1 General . 12 7.2 New tanks . 12 7.3 Existing tanks . 15 7.4 Tank design and feasibility of cathodic protection 17 8 Criteria for cathodic protection and measurement tec
13、hniques . 18 8.1 General . 18 8.2 Criteria 18 8.3 Alternative criteria and methods . 19 9 Design of cathodic protection systems 20 9.1 General . 20 9.2 Structure details and data 21 9.3 Environment . 22 9.4 Electrical isolation 22 9.5 Current requirements . 23 9.6 Cathodic protection systems and ano
14、de configuration . 23 9.7 Cable connections to the tank . 23 9.8 Reference electrodes, coupons and test stations 24 9.9 Explosion hazard prevention . 25 9.10 Galvanic anode systems 26 9.11 Impressed current systems . 26 9.12 Cables . 27 9.13 Interference 28 10 Installation of cathodic protection sys
15、tems 28 10.1 General . 28 10.2 Installation of cables 29 10.3 Isolating joints 30 10.4 Anodes . 30 10.5 Impressed current stations 31 10.6 Test stations, measuring points, permanent reference electrodes, and coupons 31 10.7 Bonding 32 10.8 Labelling . 32 10.9 Installation checks . 32 10.10 As-built
16、documentation . 33 11 Commissioning 33 BS EN 16299:2013EN 16299:2013 (E) 3 11.1 General . 33 11.2 Preliminary checking . 33 11.3 Start-up . 34 11.4 Verification of the cathodic protection effectiveness . 35 11.5 Determination of relevant measuring points . 35 11.6 Commissioning documents . 35 12 Ins
17、pection and maintenance 35 12.1 General . 35 12.2 Inspection . 35 12.3 Maintenance . 37 Annex A (informative) Groundbed data 39 A.1 General considerations 39 A.2 Types of ground beds 39 A.3 Anodes types 40 Bibliography 42 BS EN 16299:2013EN 16299:2013 (E) 4 Foreword This document (EN 16299:2013) has
18、 been prepared by Technical Committee CEN/TC 219 “Cathodic protection”, the secretariat of which is held by BSI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by October 2013, and conflicting natio
19、nal standards shall be withdrawn at the latest by October 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN-C
20、ENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary,
21、 Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. BS EN 16299:2013EN 16299:2013 (E) 5 Introduction It is important to maintain the integrity of above ground st
22、orage steel tanks (AST) for environmental and economical reasons. This European Standard applies only for external corrosion prevention, which is independent of internal corrosion issues. During the design of any new tank, a complete corrosion control study including the use of cathodic protection m
23、ethods should be performed for preventing external corrosion of the surfaces in contact with soil, cushion or foundations. When cathodic protection is adopted, it is an effective method if designed, implemented, operated and maintained in accordance with this standard. The pre-requisites for the cat
24、hodic protection should be taken into account from the basic design. In case cathodic protection is not adopted, a documented technical justification on the equivalent effectiveness of alternative methods should be given. For existing tanks, corrosion risks of external surfaces of tank bottoms may b
25、e important and possibly cause leaks, depending on the nature of soil, cushion, foundations, design of tank, and other equipment electrically connected to it such as an earthing system. Depending on the design and environmental conditions of the tank as detailed in the present standard, cathodic pro
26、tection may be effective to mitigate corrosion when designed, implemented, operated and maintained in accordance with this standard. Cathodic protection is aimed at supplying a direct current (d.c.) to the steel surface such that the steel-to-electrolyte potential is lowered to values where corrosio
27、n becomes insignificant. Cathodic protection of above ground storage steel tanks is normally used in combination with a compatible protective coating system to protect the external surfaces of above ground storage steel tank bottoms from corrosion. BS EN 16299:2013EN 16299:2013 (E) 6 1 Scope This Eu
28、ropean Standard defines the conditions necessary for an effective application of the cathodic protection method to mitigate corrosive attacks on the external surfaces of above ground storage steel tank bottoms in contact with soil, cushion or foundations. This European Standard specifies the require
29、ments for the design, implementation, commissioning, operation and maintenance of such a cathodic protection system. This European Standard applies both for new and existing tanks. NOTE 1 This European Standard is not applicable to reinforced concrete above ground storage tanks for which EN ISO 1269
30、6 applies. NOTE 2 Detailed information concerning measurement techniques of cathodic protection given in EN 13509 are referred to in the present standard. NOTE 3 Cathodic protection of internal surfaces of above ground storage steel tanks storing waters is addressed in EN 12499. NOTE 4 Cathodic prot
31、ection of external surfaces of buried tanks is addressed in EN 13636. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated referenc
32、es, the latest edition of the referenced document (including any amendments) applies. EN 13509, Cathodic protection measurement techniques EN 14015, Specification for the design and manufacture of site built, vertical, cylindrical, flat-bottomed, above ground, welded, steel tanks for the storage of
33、liquids at ambient temperature and above EN 14505, Cathodic protection of complex structures EN 50162, Protection against corrosion by stray current from direct current systems EN 60079-0, Explosive atmospheres Part 0: Equipment General requirements (IEC 60079-0) EN 60079-1, Explosive atmospheres Pa
34、rt 1: Equipment protection by flameproof enclosures “d“ (IEC 60079-1) EN 60079-2, Explosive atmospheres Part 2: Equipment protection by pressurized enclosures “p“ (IEC 60079-2) EN 60079-5, Explosive atmospheres Part 5: Equipment protection by powder filling “q“ (IEC 60079-5) EN 60079-7, Explosive at
35、mospheres Part 7: Equipment protection by increased safety “e“ (IEC 60079-7) EN 60079-10-1, Explosive atmospheres Part 10-1: Classification of areas Explosive gas atmospheres (IEC 60079-10-1) EN 60079-11, Explosive atmospheres Part 11: Equipment protection by intrinsic safety “i“ (IEC 60079-11) EN 6
36、0079-14, Explosive atmospheres Part 14: Electrical installations design, selection and erection (IEC 60079-14) BS EN 16299:2013EN 16299:2013 (E) 7 EN 60079-15, Explosive atmospheres Part 15: Equipment protection by type of protection “n“ (IEC 60079-15) EN 60079-18, Explosive atmospheres Part 18: Equ
37、ipment protection by encapsulation “m“ (IEC 60079-18) EN 60079-25, Explosive atmospheres Part 25: Intrinsically safe electrical systems (IEC 60079-25) EN 60587, Electrical insulating materials under severe ambient conditions Test methods for evaluating resistance to tracking and erosion (IEC 60587)
38、EN 61558-1, Safety of power transformers, power supplies, reactors and similar products Part 1: General requirements and tests (IEC 61558-1) EN ISO 8044, Corrosion of metals and alloys Basic terms and definitions (ISO 8044) 3 Terms and definitions For the purposes of this document, the terms and def
39、initions given in EN ISO 8044 and EN 14015 and the following apply. 3.1 cushion material in contact with the bottom of an aboveground storage tank 3.2 foundations buried construction aimed at mechanically supporting locally the above ground storage tank 3.3 hazardous area area in which an explosive
40、atmosphere is present, or may be expected to be present, in quantities such as to require special precautions for the construction, installation and use of equipment Note 1 to entry: For the purposes of this standard, an area is a three-dimensional region or space. 3.4 IR drop voltage that is the pr
41、oduct of all currents flowing through the cathodic protection circuit and the resistance of the current path (mainly the electrolyte and the tank bottom) Note 1 to entry: This is derived from Ohms law (U = I x R). 3.5 IR free potential polarised potential structure to electrolyte potential without t
42、he voltage error caused by the IR drop due to the protection current or any other current 3.6 local earthing system local earthing system for the structure under consideration which is electrically separated from any other general earthing 3.7 shield conductive or non conductive structure or object,
43、 which modifies the protection current distribution on a structure to be protected BS EN 16299:2013EN 16299:2013 (E) 8 4 Abbreviations and symbols API American Petroleum Institute AST Above ground storage tank E Potential R Resistance a.c. Alternating current d.c. Direct current ECuMetal or structur
44、e to electrolyte potential with respect to a copper/saturated copper sulphate reference electrode EHMetal or structure to electrolyte potential with respect to a normal hydrogen reference electrode EIR freeIR free potential Ecor Free corrosion potential EoffOFF potential EonON potential EpProtection
45、 potential HVDC High Voltage Direct Current IEC International Electrotechnical Commission MMO Mixed Metal Oxides T Temperature t Thickness of cushion Resistivity 5 Competence of personnel Personnel who undertake the design, supervision of installation, commissioning, supervision of operation, measur
46、ements, monitoring and supervision of maintenance of cathodic protection systems shall have the appropriate level of competence for the tasks undertaken. EN 15257 constitutes a suitable method of assessing and certifying competence of cathodic protection personnel which may be utilised. Competence o
47、f cathodic protection personnel to the appropriate level for tasks undertaken should be demonstrated by certification in accordance with EN 15257 or by another equivalent prequalification procedure. BS EN 16299:2013EN 16299:2013 (E) 9 6 Corrosion risks and their prevention by cathodic protection 6.1
48、 General The corrosion rate of a metal in soil or water is a function of the potential, E, of the material in its surrounding electrolytic environment. The corrosion rate decreases as the potential is shifted in the more negative direction. This negative potential shift is achieved by feeding direct
49、 current from anodes via the soil or water to the metal surface of the structure to be protected. In the case of coated structures, the current mainly flows to the metal surface at coating pinholes and holidays. The protection current can be provided by impressed current systems or galvanic anodes. The corrosion risks and the need and feasibility of cathodic protection for a given above ground storage tank are directly linked to the mechanical design of the storage tank bottoms and to its environment. The cushion material in contact with t