BS EN ISO 18086:2017:2018 Edition
$189.07
Corrosion of metals and alloys. Determination of AC corrosion. Protection criteria
| Published By | Publication Date | Number of Pages |
| BSI | 2018 | 48 |
PDF Catalog
| PDF Pages | PDF Title |
|---|---|
| 2 | National foreword |
| 7 | Foreword |
| 8 | Introduction |
| 9 | 1 Scope 2 Normative references 3 Terms and definitions |
| 12 | 4 Cathodic protection persons competence |
| 13 | 5 Assessment of the AC influence 5.1 General 5.2 Assessment of the level of interference |
| 14 | 6 Evaluation of the AC corrosion likelihood 6.1 Prerequisite 6.1.1 General 6.1.2 AC voltage on the structure |
| 15 | 6.2 AC and DC current density 6.2.1 General 6.2.2 AC current density 6.2.3 High cathodic DC current density 6.2.4 Low cathodic DC current density |
| 16 | 6.2.5 Current ratio “Ia.c./Id.c” 6.2.6 Soil resistivity 6.3 Corrosion rate 6.4 Pipeline coatings 6.5 Evaluation of the metal loss 7 Acceptable interference levels |
| 17 | 8 Measurement techniques 8.1 Measurements 8.1.1 General 8.1.2 Selection of test sites |
| 18 | 8.1.3 Selection of measurement parameter 8.1.4 Sampling rate for the recording of interference levels 8.1.5 Accuracy of measuring equipment 8.1.6 Installation of coupons or probes to calculate current densities 8.2 DC potential measurements 8.3 AC voltage measurements |
| 19 | 8.4 Measurements on coupons and probes 8.4.1 Installation of coupons or probes 8.4.2 Current measurements |
| 20 | 8.4.3 Corrosion rate measurements |
| 21 | 8.5 Pipeline metal loss techniques 9 Mitigation measures 9.1 General 9.2 Construction measures 9.2.1 Modification of bedding material 9.2.2 Installation of isolating joints 9.2.3 Installation of mitigation wires |
| 22 | 9.2.4 Optimization of pipeline and/or powerline route 9.2.5 Power line or pipeline construction 9.3 Operation measures 9.3.1 Earthing |
| 23 | 9.3.2 Adjustment of cathodic protection level 9.3.3 Repair of coating defects |
| 24 | 10 Commissioning 10.1 Commissioning 10.2 Preliminary checking 10.2.1 General |
| 25 | 10.2.2 Coupon AC voltage and current startup 10.2.3 Verification of effectiveness 10.2.4 Installation and commissioning documents 11 Monitoring and maintenance |
| 27 | Annex A (informative) Simplified description of the AC corrosion phenomenon |
| 29 | Annex B (informative) Coupons and probes |
| 34 | Annex C (informative) Coulometric oxidation |
| 35 | Annex D (informative) Influence of soil characteristics on the AC corrosion process |
| 36 | Annex E (informative) Other criteria that have been used in the presence of AC influence |
| 40 | Annex F (informative) Parameters to take into account to choose a DC decoupling device |
| 42 | Annex G (informative) Method to determine the reference electrode location to remote earth |
| 44 | Annex H (informative) Simultaneous measurement on coupon current densities with high rate |
| 46 | Bibliography |
