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
|Published (Last):||12 March 2008|
|PDF File Size:||14.88 Mb|
|ePub File Size:||6.38 Mb|
|Price:||Free* [*Free Regsitration Required]|
On-land pipelines 1 Scope This part of ISO specifies requirements and gives recommendations for the pre-installation surveys, design, materials, equipment, fabrication, installation, commissioning, operation, inspection and maintenance of cathodic protection systems for on-land pipelines, as defined in ISOfor the petroleum and natural gas industries. The need for additional space to accommodate temporary data-loggers, 15598-1 and other test facilities shall be considered.
In such cases, the pipelines shall be isolated from each other and provided with an individual negative connection to the current source. Key 1 electrode at position 1 2 electrode at position 2 3 electrode at position 3, corresponding to remote earth 4 electrode at position 4, corresponding to remote earth 5 soil 6 pipe The distance L between electrodes at locations 2 and 3 should be selected to cover the total extent of the potential gradient.
The location of compensation devices shall be carefully considered. As a general guide a potential difference of less than mV may be regarded as inconclusive. It can also apply to landfalls of offshore pipeline sections protected by onshore-based cathodic protection installations. In case of low soil resistivity, high a. If there are changes in soil characteristics, more measurements shall be taken. ISO shall not be held responsible for identifying any or all such patent rights.
NOTE Other direct current sources, equalizing currents, telluric currents and interference currents can influence the measurement and therefore give results which are not the true polarized potential. To avoid adverse effects on the CP, the earthing systems should be connected to the pipeline via appropriate devices, e. The minimum conductor size for measurement cables should be 4 mm2. The following information should be considered in the design of the pipeline CP system: Surge arrestors see 9.
Transformer-rectifier units and current drainage stations shall be visually checked for serviceability and damage at least annually see NOTE High voltage gradients in the soil in the vicinity of groundbeds can be a hazard to animals and persons. It is important to us that you purchase the right document.
Standards Subsctiption may be the perfect solution. All cables shall be identified by colour-coding or tags. The measurements should be carried out for a period of at least 24 h, or a period which is typical for the suspected interference phenomenon being investigated, to assess the time dependence of the interference level.
Alternatively, the space between the casing and the pipeline should be filled with a material with adequate long-term corrosion protection properties. A partially defective isolating device can not be readily identified as being defective, since the potential on both sides of the joint may still be different. Testing at the isolating joint should be done to assure that an interference condition has not then been introduced; NOTE While installing isolating joints will reduce the magnitude of the stray current, it also introduces another current pick-up and discharge location, hence the reason for testing at the isolating joint.
If other pipeline materials are used, the criteria to apply are defined under the responsibility of the pipeline operator. In these cases, alternative criteria shall be verified and applied. If a remote CP-monitoring system has been installed and malfunctioning of equipment can be immediately detected, functional checks may be conducted less frequently than recommended above.
Cables shall be sized such that no excessive voltage drops occur which reduce the capacity of the system.
The environmental impact of galvanic anodes shall be considered. A typical composition of magnesium anodes is given in Table 3. When corrosion potential measurements are carried out, all temporary CP systems shall be disconnected and the pipeline shall be fully depolarized see Figure A. In carrying out the survey, the operator walks the pipeline route taking measurements at typically 2 m intervals with the probes one in front of the other, 1 m to 2 m apart.
Resistors should be installed in the negative drains to balance the current to each of the adjacent pipelines individually. Inoperative rectifiers shall be repaired and returned to service as soon as possible, typically within 30 days.
EN Valves for natural gas transportation in pipelines – Performance requirements and tests. All contents of this part of ISO are applicable to on-land pipelines and piping systems used in other industries and transporting other media such as industrial gases, waters, or slurries. If rapid depolarization occurs, the instant-off potential shall be determined using a high speed data logging processor.
In sections where a.
ISO – Standards Australia
It is designed to cover every economic sector and virtually every activity of the humankind where technical standards may be used. 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. Protection measures against a.
In urban or industrial areas, the intervals should not be greater than 1 km. If pipelines are running in parallel, but not in the same trench, each pipeline shall be provided with separate potential-monitoring facilities.
The readings might not reflect the potential at the pipe-to-soil interface. Detrimental effects of interference currents occur at locations where the currents are subsequently discharged from the affected pipeline to the earth. This standard is also available to be included in Standards Subscriptions.
They should be buried at the pipeline depth and have adequate equipment for current measurements. If the document is revised or amended, you will be notified by email. Below-ground electrical connections shall be encapsulated or coated using a material which is compatible with the pipeline coating. The type and frequencies of further specialized surveys will depend on factors such as suspected coating deterioration, effects of elevated temperatures, construction activities, interference currents, etc.
When the CP system is energized, the drainage current should also be recorded.
Add to Alert PDF. If CP is to be applied on non-welded pipelines, the continuity of the pipeline shall be ensured. ISO consists of the following parts, under the general title Petroleum and natural gas industries — Cathodic protection of pipeline transportation systems: Devices other than the spark-gap type may be used if reliable and properly documented.
To determine the current demand for existing pipelines, where the actual condition of the applied coating is unknown, a current drainage test should be carried out.