The outer black and inner yellow HDPE double-wall corrugated pipe supplied by the manufacturer realizes functional zoning by virtue of the two-color structure: the outer black HDPE material is tight and tough, which can effectively resist underground soil extrusion and outdoor ultraviolet erosion, and avoid cracking and aging after long-term use; the inner yellow pipe wall is smooth and flat, which can reduce the friction resistance of rainwater and sewage flow, reduce the risk of blockage, and at the same time, the bright yellow is convenient for quickly identifying the pipeline transportation direction during construction, and improve operation efficiency. In terms of specifications and models, the HDPE double-wall corrugated pipe fully covers 200mm to 1200mm caliber, 200-500mm small diameter is suitable for rain and sewage diversion in residential areas and courtyard drainage; 600-1200mm large diameter meets the needs of large-scale projects such as municipal main road sewage and industrial park wastewater transportation. Manufacturers support wholesale procurement, and can deploy different caliber products according to order needs to flexibly match construction scenarios. The products are widely used in municipal drainage pipe network construction, urban old pipeline renewal, industrial park sewage collection system and residential district rainwater drainage projects. The outer black weather resistance is suitable for a variety of outdoor environments, and the inner yellow is practical and convenient. Interested wholesale purchasers can directly call the contact information 13339996652 communicate the order details.