HDPE EVOH Double Layer Composite Pipe, source manufacturer Luoyang Wohong Petrochemical Equipment
HDPE EVOH double layer composite pipe is specially developed for underground fuel transmission systems of gas stations. Adopting advanced multi-layer co-extrusion molding technology, the pipe features a pipe-in-pipe double containment structure. The inner fuel conveying pipe integrates an EVOH high barrier layer, which effectively blocks hydrocarbon permeation and suppresses fuel vapor escape, avoiding fuel loss and contamination of soil and groundwater. The outer HDPE protective layer provides secondary safety containment. The annular gap between inner and outer pipe can connect with leak detection devices for real-time interstitial monitoring. Once the inner pipe gets damaged, the outer layer can contain leaked fuel and prevent medium diffusion.
Made of high-density polyethylene raw material, this composite pipe exhibits outstanding chemical resistance. It is compatible with gasoline, diesel, biodiesel and ethanol-blended fuels. Unlike traditional buried steel pipelines, it eliminates electrochemical corrosion and maintains stable long-term performance underground. Conductive modification is available to dissipate static charge generated by fast-flowing fuel, reducing fire risks in hazardous fueling zones.
The pipeline system uses electrofusion welding with matched PE fittings. Molecular fusion between pipe and fittings forms permanent sealed joints and minimizes potential leakage points. It is supplied in continuous coil and straight pipe options. Coiled pipe greatly cuts the quantity of on-site welding joints, speeds up laying work and lowers engineering investment. With qualified backfill treatment, complicated concrete trenches are not required.
The pipe maintains stable mechanical strength under soil pressure and vehicle load. Its burst pressure is far higher than normal working pressure. A complete series of supporting fittings including elbows, tees, reducers and end caps are available to construct full underground fuel piping networks. It can be applied for fill lines, suction lines and VRU vapor recovery pipelines.
As a source manufacturer, Luoyang Wohong Petrochemical Equipment supports customized specifications according to flow demand and site layout. Our service covers raw material inspection, pipe production, factory testing, technical guidance for installation and long-term spare parts supply. Featuring high barrier performance, double containment and low maintenance, HDPE EVOH double layer composite pipe serves as a reliable underground fuel pipeline solution for new gas station construction and old station renovation projects.