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Impacts of Inductive and Conductive Interference Due to High- Voltage Lines on Coating Holidays of Isolated Metallic Pipelines
| Content Provider | Semantic Scholar |
|---|---|
| Author | Braunstein, R. Schmautzer, Ernst Oelz, Mario |
| Copyright Year | 2011 |
| Abstract | Inductive and conductive interferences of isolated metallic oil-, gas-, water- and district-heating pipelines due to short-circuit and operation currents of highvoltage lines are a well-known problem since the early 1960ies. In these times the first big so called energy routes, where high-voltage lines, electric railways and pipelines are located in the same close corridor, developed. The electromagnetic coupling between high-voltage lines and the pipeline lead to nameable induced voltages causing the risk of hazard as well as a.c. corrosion. When speaking about conductive interference, currents flow, mostly through the electric flow field in earth, from the high-voltage line to the pipeline. Conductive interference plays a role, assuming that influencing and influenced systems are close together in the same potential gradient area, either in short-circuit modes, or in normal operation modes, where currents enter through coating holidays 1 of the isolated influenced pipeline due to potential differences between the metallic pipeline and local earth. In the area of the possible coating holiday dangerous touch voltages can be picked off. In normal operation modes for example in the vicinity of transposition towers as well as electric railways, currents also can enter through coating holidays. In case of inductive interference already small induced voltages in the range of some 4-10 V lead to high current densities (above 100 A/m 2 ) at small coating holidays (for example diameters < 10 mm). Referring to European Technical Specifications very high a.c. corrosion likelihood is given from current densities higher than 100 A/m 2 . Inductively as well as conductively coupled a.c. currents flowing over coating holidays lead to extensive material removal. |
| File Format | PDF HTM / HTML |
| Alternate Webpage(s) | http://www.cired.net/publications/cired2011/part1/papers/CIRED2011_0013_final.pdf |
| Language | English |
| Access Restriction | Open |
| Content Type | Text |
| Resource Type | Article |
