Corrosion Test

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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Corrosion Failure Investigation-Case Study

The presentation of Wayne D. Niemeyer ( 2nd case starting from 17:00)  has demonstrated the importance of understanding of process and production chemistry for the corrosion root cause analysis(RCA). This principle is prompted by ASTM G161  Standard Guide for Corrosion-Related Failure Analysis The most important observation from this case is to determine the chemistry of fluid not only  from  normal production, but also from upset stage. This could be a challenge in certain plant/process due to cost-saving practice by minimising “unnecessary” monitoring. RCA may run into the dead end without weekly lubricant sample been analysed. The final conclusion was leaking of…
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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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Cathodic Protection Data Visualisation

One issue in Cathodic Protection (CP) Management is to handle large amount of data. Some specialised programs are available in the market with premium price. We are not discussing those data package, which are normally having lots of redundant functions. In CP daily management, one typical task is to visualise and comparing the data logging data from different test posts recorded in the same time. people will normally use spreadsheet such as MS EXCEL to plot the data. However, MS do have the limitation of 32,000 data point for each dataset, which is often not sufficient in CP data logging….
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Stainless Steel Pitting Corrosion

Stainless Steel Pitting Corrosion Morphology and Growth It is quite often that stainless steel developed porous metallic lacy structure during pitting corrosion. Steel pits are partially covered by remaining passive film.  The passive film covering the pit is not existed any more. The passivation layer in the pit is not an effective barrier for the diffusion. Newman et al developed a model to demonstrate the initiation, developing and growth of pits in stainless steel. During initial stage (a), the passivation layer of stainless steel was destroyed, in which a pit is initialised. However, the mouth of the pit became re-passivated,…
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