XQV Metal Corrugated Duct – High‑Strength Steel Duct for Post‑Tensioning Systems

XQV metal corrugated ducts are available in both flat and circular sections. They are manufactured from galvanized or non‑galvanized thin steel strip through corrugating, spiraling, folding and closing using a pipe rolling machine. The ducts offer good strength, light weight, easy bending, simple connection, low friction coefficient and excellent bond with concrete. They are the ideal material for post‑tensioning duct forming in prestressed concrete structures, and are typically used with matching couplers.

The flat duct has a rectangular‑like shape with the horizontal dimension larger than the vertical dimension, occupying minimal space. It is especially suitable for thin structural members such as bridge wings, floor slabs, and other areas with limited concrete cover thickness – allowing reduced protective layer and optimized section design. Its flexible shape facilitates curved prestressing tendon layouts and is particularly applicable to components requiring multi‑directional tensioning (e.g., negative moment zones of continuous beams). However, lateral stiffness is relatively low; the flat duct may buckle under pressure if not properly supported. Therefore, during installation, it must be fixed with positioning bars to prevent deformation during concrete pouring.

The circular duct has a standard round cross‑section, providing isotropic mechanical properties and uniform force distribution. It features high radial compressive strength, effectively resisting lateral pressure during concrete pouring with minimal deformation. It is ideal for long‑span ducts or large‑diameter prestressing tendons (e.g., multi‑strand bundles). Installation tolerances are relatively generous, and it offers broad compatibility with various anchorages and couplers. The smooth inner wall reduces friction losses during tensioning, minimising prestress loss. Circular ducts are widely used in precast beams, long‑span bridges, and other major structures.

With its strength and stiffness advantages, the metal corrugated duct is suitable for large‑scale structures, precast components, and projects where high duct support is required in conventional environments. Anti‑corrosion treatment should be applied where necessary. Typical applications include:

• Bridges & Highways: Post‑tensioning ducts for box girders, segmental beams, and cable‑stayed bridges.
• Precast Concrete Beams: Duct forming for railway sleepers, T‑beams, and hollow slabs.
• High‑Rise Buildings: Post‑tensioned slabs, transfer plates, and foundation works.
• Heavy Civil Structures: Containment walls, silos, water tanks, and large industrial foundations.

※ Parameters for reference only. Dimensions and coatings can be customised. Final interpretation right belongs to our company.