HDPE Double Wall Pipe

I Product Introduction

HDPE double-wall corrugated pipe is a structured-wall pipe manufactured from high-density polyethylene using twin-extrusion and vacuum forming processes. It features a smooth inner wall and a corrugated outer wall, with a hollow structure between the inner and outer walls. The product is produced using fully digitalized process control, with integral socket forming during online belling. The corrugated structural design saves more than 30% of raw material compared to solid-wall pipes under the same loading conditions, while offering both high ring stiffness and flexibility. The pipe is suitable for buried drainage, sewage, and communication conduit applications with a long-term service temperature below 45°C, and is widely used in municipal engineering, residential complexes, and agricultural water conservancy projects.

I Product Features

● Corrugated reinforcement for outstanding pressure resistance: The annular corrugated outer wall significantly improves ring stiffness (available in SN4–SN8), enhancing the pipe’s resistance to soil loads. The double-wall hollow design achieves a balance between lightweight construction and high strength, with excellent pressure and impact resistance.

● Smooth inner wall for superior flow capacity: The smooth inner surface minimizes friction, with a Manning coefficient as low as 0.009. For the same diameter, flow capacity is more than 30% higher than that of concrete pipes. The non-scaling, bacteria-resistant surface ensures long-term high flow performance.

● Flexible jointing for zero leakage: Rubber seal rings provide flexible, tightly fitted push-on joints that are leak-proof. The flexible joint effectively resists uneven soil settlement and seismic shocks.

● Corrosion resistance, abrasion resistance, and strong adaptability: HDPE is a non-polar material with excellent chemical stability and strong resistance to acid and alkali corrosion. Its abrasion resistance is 3–5 times higher than that of steel pipes. With a brittle temperature of –70°C, the pipe maintains good toughness even under low-temperature conditions.

● Lightweight, high strength, and easy installation: The lightweight design makes handling and jointing easy, with no need for lifting equipment. Short installation cycles reduce overall project costs. The pipe can be slightly deflected axially, allowing direct installation in slightly uneven trenches.

I Technical Data

I Product Specification

I Application

● Municipal drainage and sewage projects: Widely used in urban stormwater and sewer systems.

● Building drainage systems: Used for building rainwater pipes, underground drainage pipes, sewage pipes, and ventilation pipes.

● Communication infrastructure protection: Serves as protective conduits for communication cables and fiber optic cables.

● Road engineering drainage: Used for railway and highway seepage pipes and drainage pipes.

● Agricultural water conservancy projects: Suitable for irrigation and drainage networks in farmland, orchards, tea plantations, and forest belts.

● Mining engineering: Used for mine ventilation, air supply, and drainage pipes.

● Industrial wastewater treatment: Used for wastewater pipes in chemical, environmental protection, and other industries.

I FAQ

1. What is the difference between HDPE double-wall corrugated pipe and ordinary solid-wall pipe?

The core difference lies in the structural design: double-wall corrugated pipe has a smooth inner wall and a corrugated outer wall, with a hollow structure between them. This design saves 30%–50% of raw material compared to solid-wall pipe under the same loading conditions, resulting in a lighter weight, while the corrugated structure significantly enhances ring stiffness and external pressure resistance.

2. What is the service life of HDPE double-wall corrugated pipe?

Under normal buried conditions without direct exposure to sunlight, the service life of HDPE double-wall corrugated pipe can exceed 50 years. It has an oxidation induction time of ≥20 minutes (at 200°C) and excellent resistance to environmental stress cracking, ensuring stable long-term performance.

3. How to select the appropriate ring stiffness class?

Selection is based on burial depth and ground loading:

● SN4: Suitable for shallow burial depths and areas without heavy loads.

● SN8: Suitable for conventional municipal roads with burial depths of 4–6 meters.

● SN12.5/SN16: Suitable for deep burial, heavy traffic loads, or areas with a high groundwater table.

Specific selection should be based on design drawings and geotechnical investigation reports.

4. Can HDPE double-wall corrugated pipe be used for pressure applications?

HDPE double-wall corrugated pipe is primarily designed for non-pressure or low-pressure gravity flow systems, such as drainage, sewage, and stormwater networks. The operating pressure is typically below 0.6 MPa. For pressure applications, solid-wall HDPE pressure pipes should be used.

5. What jointing method is used for double-wall corrugated pipe, and how is leak-proof performance ensured?

The pipe uses flexible rubber seal ring joints. During installation, the following must be ensured:

① The rubber ring is correctly placed in the socket groove without damage or deformation;

② The socket and spigot are clean and dry;

③ The insertion depth is sufficient;

④ The relative angular deflection at the joint complies with specification requirements.

This flexible joint effectively accommodates soil settlement while maintaining long-term watertightness.

6. What temperature conditions are suitable for double-wall corrugated pipe?

HDPE double-wall corrugated pipe has a service temperature range of –60°C to 60°C, but the long-term service temperature is recommended not to exceed 45°C. It has a brittle temperature of –70°C and maintains good toughness even under low-temperature conditions, making winter installation convenient.