The pig caliper gauge has two different diameters. A worn pig fits through both sides of the gauge. A brand new pig fits into the "GO" side, but not into the "NO GO" side. With the pig caliper gauge the pig's minimum pre-tension is measured in order to make sure that it is sufficient to obtain a good pigging result.
The use of worn pigs can lead to following problems:
- More product residuals in the pipeline, caused by insufficient stripping performance of the pig
- Product mixture
- Aging products in the pipeline
- More sediments in the pipeline