Electrofusion Joint Krah Pipe Spiral HDPE Structured Wall Pipe

Polyethylene (PE) Spiral Structured Wall Pipe (Type B), commonly known as Krah Pipe, is a high-performance flexible conduit manufactured from premium polyethylene raw materials. The pipe is fabricated using an advanced hot-state spiral winding process and sequentially cooled via an engineered rolling-air cooling system before demolding. Structurally, it features an ultra-smooth interior surface complemented by a spirally wound, profiled reinforcing rib on the exterior.

HDPE Spiral Wound Reinforced Pipes utilize an integrated socket-and-spigot electrofusion jointing system. During production, the two ends of the pipe are precision-profiled into a bell (socket) and a spigot, with high-efficiency electrofusion wires permanently embedded into the socket end. On-site jointing is exceptionally straightforward—requiring only a standard power source connectivity to complete a homogeneous fusion weld, resulting in a 100% leak-free piping network.

This product is widely deployed in municipal drainage and sewerage, electrical ducting, petrochemical networks, coal mine ventilation, and other demanding infrastructure applications. Serving as an ideal substitute for traditional reinforced concrete and cast iron pipes, it represents a rapidly growing advancement in underground gravity-flow drainage and has been designated as a Top-Priority Promoted Product by the Ministry of Housing and Urban-Rural Development (MOHURD).

The definitive feature of the Krah Pipe is its jointing mechanism. During production, one end is formed into a socket (bell) and embedded with electrical-resistance fusion wires, while the other end is formed into a spigot.

The Fusion Process: On-site connection requires only a standard power control unit. When energized, the interfaces melt and fuse at a molecular level, creating a completely homogeneous, 100% watertight joint that completely eliminates groundwater infiltration and exfiltration.

As a flexible conduit, it acts cooperatively with the surrounding soil. Under heavy traffic or sudden heavy overhead loads, it deflects elastically to dissipate localized stress. This makes it immune to cracking or shattering, unlike rigid concrete pipes.

Made from high-density polyethylene, it is completely inert to hydrogen sulfide gas ($H_2S$), acidic or alkaline soils, and aggressive chemical effluents. It is highly ductile, making it the perfect choice for unstable ground, soft soil coastal areas, and seismic-prone zones.

• Municipal Sewage Trunk Lines: Ideal for major urban deep-buried drainage networks and sewage collector lines.

• Petrochemical & Industrial Effluents: Safe conveyance of corrosive chemicals, mine slurry, and aggressive industrial wastewater.

• Marine & Coastal Engineering: Extensively used for sea outfalls, marine water intake lines, and desalination plants due to total saltwater immunity.

• Industrial Ventilation: High-efficiency air ducting and ventilation networks for coal mines and tunnels.

• Non-Disruptive Trenchless Installation: Suitable for micro-tunneling and pipe-jacking applications.