SpiralLining

SpiralLining is a technique and family of products used to reinforce or line circular structures by applying a continuous liner that is wound helically around the interior. The liner is bonded to the substrate with adhesive or resin systems to form a smooth, sealed interior surface. The helical winding distributes stress and can be tailored by adjusting the winding angle, material, and overlap.

Process and materials: The system uses flexible liner materials such as fiber-reinforced polymers, reinforced thermoplastics, or cured epoxy resins. The liner is wound at a controlled helix angle and bonded to the host wall through adhesive or in-situ-curing resin. The spiral wrap can include a partial overlap to ensure a watertight seal and may incorporate stiffening fibers for load transfer. Installation can be performed from one or both ends, often through existing access points, requiring limited excavation and disruption.

Applications: SpiralLining is employed for rehabilitation of deteriorating pipelines and culverts, reconstruction of ventilation ducts, and corrosion-resistant linings in chemical tanks. It is also used for structural rehabilitation of circular concrete columns or shafts and for creating smooth interior surfaces to improve flow or reduce leakage.

Advantages and limitations: Benefits include rapid installation, minimal site disruption, corrosion resistance, and improved hydraulic smoothness. Limitations include the need for interior access, surface preparation requirements, and defined temperature and pressure limits; post-installation inspection is often necessary to verify seam integrity and bond quality.

History and related terms: The approach emerged in the late 1990s and 2000s as an evolution of spiral winding concepts and cured-in-place pipe technologies, with various manufacturers offering SpiralLining systems. Related terms include spiral winding, CIPP, and pipe rehabilitation.