Pipeline inspection

Pipeline maintenance

THE DIFFERENT PIGS AND THEIR USE

Foam pigs:

  • These are comprised of a polyurethane foam cylinder possibly with a polyurethane coating.

    Low density foam pistons: used for wiping pipelines after draining.

    Medium or high density foam pistons with coated bottom: used for water filling or draining short pipelines.

    High density foam pistons with coated bottom and crisscrossed body: same use as above for longer pipelines.

    High density foam pistons with coated bottom and crisscrossed body equipped with metal hairs: used for cleaning pipelines, and dusting gas pipes.

Gel pigs:

  • Gel pigs are cylinders of gel that are made in situ just before their insertion into a pipeline.

    They are generally used for draining pipelines that are badly distorted or that have severe restrictions.

Separation pigs:

  • used for:
    • separating products in oil pipes,
    • filling pipelines for water tests,
    • draining pipelines after tests.

Cleaning pigs:

  • used for:
    • periodic scraping of oil pipes (crude oil transportation),
    • scraping of operational pipelines conveying products liable to create deposits,
    • cleaning of encrusted or even partially obstructed pipelines,
    • removal of internal coatings.
Instrumented tools