Corrosion In Pipelines

1611 Words7 Pages
The concept of cavitation was birthed in the 19th century as a result of the difficulties it presented in rotating machinery when its effects were first identified in ship performance. Cavitation refers to the phenomenon that result from sudden drop in fluid pressure. When the pressure of fluid is reduced, it in turn lowers the boiling point of the liquid. This reduction causes vapor bubbles to form when the fluid boils and these vapor bubbles flow through areas with higher pressure. Eventually, these quickly collapse producing shockwave, noise, and vibration that can damage components of a machine. This is typically observed at the inlet where there is low pressure.
Cavitation is a characteristic of all liquids as soon as their pressure equal
…show more content…
Fluid hammer can be identified such as a pressure wave caused when a fluid in most cases liquid in motion changed direction in other words momentum change. This phenomenon called hydraulic or differential shock, occurs when a valve closes suddenly at any point of one pipeline and a pressure surge spread in the pipe, also identified as the momentary increase in pressure inside a pipeline. Furthermore fluid hammer has caused to break or damage pipes, valves, system components…show more content…
One key type of corrosion popular in the pipelines is the pitting Corrosion. This type of corrosion in the pipelines remain as localized corrosion occurring on the surface of the metal and is restricted to one point or small area of the pipeline thus taking after some form of cavities. Pitting corrosion remains among the most damaging corrosion forms.
It is popular across pipelines and is much prevalent in passive metals and alloys, which typically include stainless steels, aluminum alloys, and stainless alloys among others. These are more prone to pitting corrosion given that the ultra-thin passive film (oxide film) in these is mechanically or chemically interfered with and would not re-passivate immediately. The pits that result from such damage either grow wider and shallow or narrow and deep thus rapidly perforating the wall thickness of a metal.
To control such pitting corrosion, there would be a need for appropriate selection of materials in which the key consideration would involve established resistance to the service environment. Secondly, pitting corrosion may be controlled by ensuring the pH, chloride concentration and temperature are adequately controlled. Further, intervention strategies would involve cathode and Anodic Protection in addition to the use of higher alloys in ensuring better resistance to pitting

More about Corrosion In Pipelines

Open Document