Corrosion Management

Electrical Short Pipeline Potential Measurement and its Implication in Pipeline CP Management Practice

This is a paper published in Corrosion Management Magazine ( September 2018, issue 145). It can be accessed from IoCC website. The most important performance indicator for cathodic protection (CP) is the structure-to-electrolyte potential. In most of coated on-shore pipeline, the resistance between the reference electrode and the pipe-to-soil surface boundary is too significant to be ignored.  The IR drop caused by CP current is a measurement error. It is stipulated in many CP standards that IR component to be evaluated and excluded while assess the pipe-to soil potential performance in pipeline integrity management. For a well-coated pipeline, the most…
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Corrosion of Embedded Ferrous Metals in Woods

Timber is the most widely utilised natural materials in human history. It is a renewable material and readily available. Ferrous metal fasteners and fixtures are often used in the timber structure. They are generally reliable and maintenance free.  However, the pre-mature corrosion failures are identified in the history [1].  Field experience and test even suggested higher corrosion risk for outdoor applications [2]. If not attending carefully, it will lead to serious consequence.  Corrosion scientists also believe that wood provides a corrosive environment through permeable structure acting as an electrolyte sponge.  Recent research is not only focusing on understanding the corrosion…
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Adenosine Testing and its Interpretation in Oil and Gas Field Microbial Status

Microorganisms can cause multiple threats in oil and gas production (EFC 9 ), injection and fracturing operations. Those threats range from production downtime due to microbial influenced corrosion (MIC) downhole and on surface equipment, to formation souring, as well as flow disruption caused by overgrowth of biomass in flow lines ((EFC29 ). Adenosine analysis, particularly ATP field tests  (NACE, TM0212) (NACE, TM0194), have been introduced into oil and gas for microbial status assessment. It facilitates a fast field screening Test for microbial status  comparing to the labour intensive and time consuming culturing techniques. However, the challenge is on results interpreting. Understanding the…
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Hydrotest Water Specification and Integrity Considerations

The pipeline and pressure vessel are required by code to perform hydrotest after their construction, maintenance to demonstrate the strength and integrity. Water is the most common media to be used in this test. There are several standards and code of practice in place for the quality of hydrotest water.  Nevertheless, there is still multiple case of failure while the inappropriate water was used for the hydrotest, which has been proven costly in rectification.

MFL Tool for In-line Inspection (ILI)

Principle of Magnetic Flux Leakage (MFL) A magnetic flux leakage (MFL)  inspection is the type of in-line inspection technology in which a magnetic saturation is induced in the pipe wall between two poles of a permanent strong magnet. The pipe wall is magnetised by using this magnet. Anomalies affect the distribution of the magnetic flux in the wall, by which it is used to detect and characterize anomalies accordingly. Any metal-loss in the pipe wall will cause the induced magnetic flux leakage, which can be monitored using a detector and hence metal-loss defects can be identified and sized. MFL can…
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