Corrugated conduits are tubes with a series of parallel ridges and grooves on their surface. The tube can be made of steel or plastic, such as high density polyethylene (HDPE) or PVC. It can be coated or lined. Corrugated conduits are used in applications such as drain pipes, where flexibility, durability and strength are important attributes.
Corrugated conduits of small size can be seen in common applications, such as drain pipes used to run off from drains on the eaves of homes. Larger-sized pipes are used as rain drains and culverts under bridges and roads. The flexibility of the bellows makes it more suitable for various purposes than rigid smooth tubes. The height of the corrugation is measured by the height of the ridge; the higher the number, the more flexible the pipeline.
Corrugations can create friction inside the pipeline or catch debris in ridges. In some applications, coatings or linings can improve the flow of materials through pipes. The plastic tube can be made corrugated on the outside and made smooth on the inside.
