"Despite efforts at utility meetings and conferences such as the American Water Works Association, many water system managers remain unfamiliar with pigging," Cubage says.
Cubage says that pigging is most appropriate for water lines and force sewer mains.
For utility pigging, Cubage says "poly pigs" constructed of open cell polyurethane foam with several types of external wrappings are used.
Says Cubage: "In raw water transmission mains, the primary reason for pigging is to increase flow rates and lower pump pressures.