1) Cleaning tool 2) Petroleum production 
Pigging in the context of pipelines refers to the practice of using devices known as `pigs` to perform various maintenance operations on a pipeline. This is done without stopping the flow of the product in the pipeline. These operations include but are not limited to cleaning and inspecting the pipeline. This is accomplished by inserting the pig.....
• (p. pr. & vb. n.) of Pig