Kela pipe is a type of flexible tubing characterized by a smooth inner wall and an outer wall featuring spiral reinforcements. It is constructed with an O-shaped rib structure formed by a base film and rib interface, using a spiral winding process. Made from high-density polyethylene, it is shaped in one step during a hot melting state via the winding technology. Before demolding, it is cooled through a rolling air-cooling method, allowing for gradual heat dissipation and resulting in uniform wall thickness with no internal stress.