Prestressed plastic corrugated pipes are manufactured from HDPE. They are mainly used for duct forming of tension bars in post-tensioned prestressed concrete structures. Featuring good sealing performance, no slurry leakage, high ring stiffness, low friction coefficient, ageing resistance, electrolytic corrosion resistance, good flexibility, and resistance to damage by vibrating pokers. Their innovative connection design facilitates easier on-site jointing. These pipes are widely applied in long-span tension projects such as highways, railways, bridges, slopes and high-rise buildings.