Gourt Home::Gourt :: Pipeline inspection gauge
A pipeline inspection gauge or PIG in the pipeline industry is a tool that is sent down a pipeline and propelled by the pressure of the product in the pipeline itself. It is the chief tool used in pigging. The acronym is usually written pig (and pronounced as such).
A 'pig' is typically a soft, bullet shaped polyurethane plug that is forced through pipelines to clean them, separate products to reduce mixing, and inspect the pipeline. There are several types of pigs; some have tungsten studs or abrasive wire mesh on the outside to cut rust, calcium, or paraffin deposits off the inside of the pipe, others are plain plastic covered polyurethane.
Inline inspection pigs use various methods for inspecting the condition of a pipeline. A sizing pig uses one (or more) notched round metal plates that are used as gauges. The notches allow different parts of the plate to bend when a bore restriction is encountered. More complex systems exist for inspecting various aspects of the pipeline. Intelligent pigs incorporate a computer or electronics which collects more information. These pigs use technologies such as MFL (Magnetic Flux Leakage) and ultrasonics to detect the various aspects of the pipeline. 'Intelligent' or 'smart' pigs may also use calipers to measure the inside geometry of the pipeline.
The first Inline Inspection or smart pig was run in 1964 by Tuboscope Pipeline Services. This inspection tool used MFL technology to inspect the bottom portion of the pipeline. The recording system used a flight data recorder black box to store the information.
See also
External links
"Pipeline inspection gauge"