Engineering Phenomena

"Pigging" in the context of pipelines refers to the practice of using a pipeline inspection gauge or "pig" to perform various maintenance and cleaning tasks within a pipeline. The goals of pigging include product removal, cleaning, and ensuring the pipeline remains in good condition. Here are some key points from the provided text:

"Pigging" in the context of pipelines refers to the practice of using a pipeline inspection gauge or "pig" to perform various maintenance and cleaning tasks within a pipeline. The goals of pigging include product removal, cleaning, and ensuring the pipeline remains in good condition. Here are some key points from the provided text:

Surge analysis is the study of pressure transients caused by a change in the piping system. This change may be something as simple as a valve closing or opening, or something more complicated such as a pump, or multiple pumps, starting up or shutting down, either in a planned or unplanned way.

Spontaneous phenomenon of material decay due to the interaction with an aggressive environment OR  destructive attack of a chemical. The consequence is a decay of CHEMICAL-physical properties of materials, depending on the nobleness of metal. These Physicochemical changes are described by the following terms: corrosion–erosion, corrosive wear, or fretting corrosion. 

Image Credit: https://www.rosen-group.com/global/solutions/services/pipeline-corrosion.html

Before the advent of the catalytic cracking process, thermal cracking was the primary process available to convert low-value feedstocks into lighter products. Refiners still use thermal processes such as delayed coking and visbreaking for cracking of residual hydrocarbons.