EVOH Barrier HDPE Double Wall Composite Pipe for Underground Fuel Transfer｜Vohon Petrochemical
EVOH barrier HDPE double wall composite pipe is designed for underground fuel transfer systems of filling stations. Produced by multi‑layer co‑extrusion molding technology, the inner pipe is embedded with an EVOH barrier layer to block hydrocarbon permeation and reduce fuel vapor escape. The pipe‑in‑pipe double wall structure provides secondary containment protection. The annular gap between inner medium pipe and outer HDPE protective pipe can be linked with leak monitoring instruments for real‑time interstitial detection. Once the inner pipe is broken, the outer pipe can contain leaked fuel and avoid contamination of soil and groundwater.
Made of high‑density polyethylene base material, the composite pipe shows excellent chemical resistance. It is compatible with gasoline, diesel, biodiesel and ethanol‑blended fuels. Compared with buried steel pipelines, it has no risk of electrochemical corrosion and can keep stable performance in long‑term underground environments. Conductive modification is optional to eliminate static accumulation caused by high‑speed fuel flow inside pipelines and reduce fire risks in hazardous areas.
The pipeline uses electrofusion connection with matching PE fittings. Electrofusion welding achieves molecular fusion between pipe and fittings to form permanent sealed joints and cut down potential leakage points. The pipe is available in continuous coil and straight pipe options. Coiled pipe reduces the number of on‑site joints, speeds up laying work and lowers construction cost. With proper backfill treatment, complicated concrete trenches are not required. It is suitable for new filling station construction as well as reconstruction and expansion of old fuel stations.
The pipe system maintains good mechanical strength under soil pressure and ground traffic load. Its burst pressure is much higher than normal operating pressure. A complete set of supporting fittings including elbows, tees, reducers and end caps can be supplied to build full underground fuel transfer networks, covering fill lines, suction lines and VRU vapor recovery pipelines.
Thanks to the EVOH high barrier layer, hydrocarbon permeation loss is effectively controlled to satisfy strict environmental regulations for fuel retail sites. Various nominal diameters can be customized according to flow capacity and site layout demands. With high safety performance, anti‑permeation characteristic and low later maintenance cost, EVOH barrier HDPE double wall composite pipe offers dependable underground fuel transfer solutions for global gas station projects.