STANDARD. ISO. First edition. Petroleum and natural gas industries —. Cathodic protection of pipeline transportation systems —. Part 1. Purchase your copy of BS EN ISO as a PDF download or hard copy directly from the official BSI Shop. All BSI British Standards. STANDARD. ܚ. ISO. First edition. an Petroleum and natural gas industries -. Cathodic protection of pipeline transportation systems
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ISO – Standards Australia
There are a number of measurements that can be carried out to determine the effectiveness of lso installed isolating joint or isolating flange kit, as described in A. Surge arrestors see 9. Subscription pricing is determined by: Izo conditions can include shielding e. In case of low soil resistivity, high a. Where necessary, metallic casings should 155899-1 used for stabilizing the borehole in the active section of the groundbed.
The values obtained from the testing shall be the basis for the design of the system. Alternative corrosion control methods should be considered in such cases. Inoperative rectifiers shall be repaired and returned to service as soon as possible, typically within 30 days. If the area to be surveyed is affected by seasonal changes, these shall be taken into account and the most severe conditions with respect to the soil conditions shall be used for the design.
The removal of the protective coating from the pipe should be kept to a minimum.
For such metals, the potential shall not be more negative than a limiting critical potential El. Significant positive shifts in pipeline potential, such as those due to stray-current interaction, shall be corrected within 30 days Annex B.
Some earthing systems can have an adverse effect on the effectiveness of the CP. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. Care shall be taken to ensure that isolating devices are not unintentionally electrically by-passed after installation.
Representative soil resistivity values should be obtained at pipeline depth along the route of the pipeline, and shall be obtained at various depths at prospective locations for anode groundbeds. Drainage stations Measure drain-point potential and the current at least monthly Connections to foreign pipelines Measure current flow at least annually Bonding devices and grounding systems Measure electrical continuity at least annually Safety and protection devices Measure settings and function at least annually At monitoring stations Measure instant-off potentials annually a Less frequent measurements may be considered based on results of specialized surveys see Two operators walk along the route, making the necessary contacts with the soil, usually via cleated boots.
Permanent monitoring facilities connected to the pipeline should be installed simultaneously with the pipeline to allow monitoring of the performance of the temporary system. This equipment also requires routine calibration and periodic safety checks. Other alloys may be used provided the performance in similar soils is reliable and documented.
Usually, the interfering current from a foreign source, not electrically continuous with the affected pipeline, is drained from the soil by the affected pipeline.
They shall be retained for use as a baseline for future verifications of CP effectiveness. The mean change of potential at any part of another pipeline or installation from interference should not cause potentials outside the criteria given in 5. An increase in the recorded potential difference can indicate a coating defect or iwo metallic object in close proximity to the pipe. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
NOTE If the a. The metallic casing shall be electrically isolated from any structures on the surface.
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The design, materials, dimensions and construction of the isolating joints shall meet the design requirements of ISO Current attenuation surveys are based on the assumption that when an a. If CP is to be applied on non-welded pipelines, the continuity of the pipeline shall be ensured. ISO shall not be held responsible for identifying any or all such patent rights. Resistors should be installed in the negative drains to balance the current to each of the adjacent pipelines individually.
The pipe-to-soil potential shall be measured to verify CP effectiveness using the protection criteria in 5. Proceed to Checkout Continue Shopping. NOTE Special conditions sometimes exist where cathodic protection is ineffective or only partially effective. A partly defective isolating device may not ios readily identifiable by this method, since the current in the bond may not be zero if the leakage resistance and the bond resistance have similar magnitudes.
Measurements of potential are plotted versus distance, from which features can be identified lso changes in potential caused by local variations in CP current density. Performance of the CP 15589- equipment, e. 15859-1
BS EN ISO 15589-1:2017
Any such effects shall be investigated and their likely impact upon the integrity of the pipeline and the safety of personnel shall be determined see Annex B. NOTE 2 Possible effects associated with a.
Table 4 — Routine functional checking frequencies Item Action Frequency Impressed-current station Check that the operation and condition of the transformer-rectifier unit is satisfactory and record the output voltage and current every one to three months depending on operational conditions such as lightning, stray currents, construction activities.
Immediate action shall be taken if positive changes in pipeline potential occur after energizing the transformer-rectifier. The continuity of non-welded pipelines shall be checked by carrying out resistance and potential measurements, see Annex A. The need for, and the type of, CP for thermally-insulated pipelines shall be subject to an additional evaluation taking into account the following.
Alternatively, the space between the casing and the pipeline should be filled with a material with adequate long-term corrosion protection properties.
Safety-earthing and instrument-earthing shall be mutually compatible with the CP system. In the calculation of the groundbed resistance, the soil resistivity data corresponding to the centre-line horizontal groundbed or mid-point vertical groundbed of the anodes shall be used and the possibility of multi-layered soils with significantly different soil resistivities considered.
These actions can include one or more of the following: Where an alternative 155891 offered, any variations from this part of ISO should be identified. On-land pipelines This document has been re-assessed by the committee, and judged to still be up to date. If the use of monobloc isolating joints is not practical, electrical isolation should be provided using isolating flange kits. For buried pipelines, the potential measured against the reference electrode shall be measured, generally within 1 s after the protective current is switched off.