Pipeline gauging detects any internal restrictions and gives indicative results as to whether the pipeline is geometrically suitable for the progression to more aggressive cleaning pigs. Gauging is achieved by fitting a pig with an aluminium plate, sized proportionally to the minimum internal diameter of the pipeline.

Steel bodied pigs such as a Bi-Directional Pig or Flexi-Cupped Gauging Pig are often used for pipeline gauging. These pigs are fitted with a combination of polyurethane guide discs and seal discs or cups. Depending on pipeline diameter, transmitters and magnets can usually be fitted for pig tracking and pig location purposes.

Whilst these pugs should offer only light cleaning, they should be fitted with pluggable by-pass ports to front of the pig body to help flush any accumulated debris ahead of the pig.

Gauging plates are available in multiple body options, from steel to polyurethane to foam. They are manufactured to any thickness or diameter. Used in conjunction with pigs, they are used to prove pipe roundness and indicate obstructions or internal damage of a pipeline.