Foam pigs are a versatile type of pipeline cleaning device. They are used for drying, cleaning, batching, and product removal operations. Because they are lightweight and flexible, foam pigs are able to negotiate uncommon piping, fittings, and valves.

Bare pigs are constructed of medium or heavy-density foam and coated with polyurethane elastomer on a base. They are used for drying and sweeping of loose debris. However, other functions include using as a gauging pig for determining internal pipe conditions prior to extensive pigging, using as a sealing pig behind a stuck pig, using for batching and product removal, and for pigging where low volumes and pressures are present. Options and other configurations include double-dish, double-nose, pulling rope or cable, transmitter or pinger cavity, jetting bypass ports, magnets, and customized diameters and lengths for special pigging applications.