FLEXWELL-HL: Flexible Stainless Steel Pipe for Hazardous Media

Pipe System for Industry/Commercial | Marinas | Generators

The FLEXWELL-HL pipe system is specifically designed for hazardous fluids and gases, such as gasoline, ethanol blends, biodiesel, LPG and other hazardous fluids typically transported in chemical plants. The pipe is used in gas stations underground as well in above ground applications such as marinas and bulk facilities.

FLEXWELL-HL can operated as a suction or pressure systems and can be continuously monitored via suitable and approved leak detection systems.

Applications in Fueling and Industrial Infrastructure

FLEXWELL-HL is engineered for a wide range of critical applications, including:

✅ Underground and above ground fuel supply lines
✅ Floating dock marinas with strong tidal variations
✅ Suction, pressure, and fill pipes
✅ Tank farms, chemical plants, and LPG systems
✅ Commercial fueling stations

Marina Innovation: Seamless Pipe Runs for Floating Docks

Fuel piping installation in floating dock marinas has been redefined through the use of the FLEXWELL-HL double-wall stainless steel pipe. This system eliminates all connections above water, allowing for continuous “home run” pipe runs from tank to dispenser. Leveraging the inherent flexibility of FLEXWELL-HL, the design compensates naturally for tidal changes in floating dock environments. With several proven configurations, systems have been successfully implemented to handle tides of up to 17 feet—without the need for additional components.

This advanced solution increases safety, reduces potential leak points, and simplifies maintenance.

Double-Wall Safety 

FLEXWELL-HL features a seamless, helically corrugated stainless steel inner and outer pipe (SS 316 L/1.4404) with a continuous interstitial space designed for leak detection using either pressure or vacuum monitoring systems. This double-wall construction ensures maximum environmental protection, even in the event of damage to the inner pipe, and delivers reliable performance with current and future fuel blends. A polyethylene outer jacket provides additional corrosion resistance and mechanical protection.

Performance and Technical Specifications

✅ Operating pressure: up to 145 PSIG (10 bar)
✅ Sizes: ID 1" (DN 25) to 3" (DN 80)
✅ Temperature range: –50 °C to +60 °C
✅ For LPG: up to 360 PSIG (25 bar) with reinforced fittings
✅ Fire rating: Two hours per UL 1369

Two Hour Fire Rating

FLEXWELL-HL  has a two hour fire rating per UL 1369

Efficient Installation in Long Lengths

FLEXWELL-HL is supplied in continuous factory lengths of up to 3,000 feet, enabling fast and efficient installation with minimal connection points. The system can be laid directly into a trench without the need for intermediate joints or fittings. Its corrugated stainless steel design offers both high impact resistance and exceptional flexibility—making it especially well-suited for complex routing and for use in floating dock marinas where adaptability is essential.

FLEXWELL-HL is the stainless steel pipe system of choice for safe, compliant, and flexible fuel transport — underground, above ground, and across tidal marina environments.