A BRUGG GROUP COMPANY
The FLEXWELL District Energy Cable‑FHK is an advanced, flexible, and highly durable piping system engineered for the most demanding applications in district energy, district cooling, and domestic hot water systems.
Offering a reliable solution for complex installation challenges, it delivers exceptional efficiency, safety, and long-term performance.
The FLEXWELL-FHK features a 100% diffusion-tight steel jacket, delivering outstanding thermal insulation, dependable operation, and high energy efficiency—even in the most demanding conditions.
A major benefit is its PUR foam insulation’s diffusion-tight design, which fully protects against moisture intrusion and significantly extends service life compared to conventional piping systems. An integrated bitumen layer further enhances durability, offering robust mechanical protection during trenchless installation or in challenging soil environments.
In addition, the spiral corrugation of the carrier pipe ensures superior ventilation and exceptional resistance to deposits, supporting long-term performance and reliability.
The ideal answer to any installation challenge. Trenchless installation via horizontal directional drilling (HDD) allows precise, surface-friendly placement, protecting traffic routes and natural environments. FLEXWELL-FHK is engineered for extreme conditions, with exceptional bending flexibility to navigate obstacles, perfect for:
✅ Roadway crossings
✅ Railway crossings (approved by German DB InfraGO)
✅ Waterway crossings
✅ Installation in wet soils or groundwater areas
✅ Renovation and expansion of existing piping networks with minimal excavation
✅ Installation through protected environmental areas
High Flexibility & Versatility
→ Install without couplings, welding, or complex insulation work
→ Perfect for demanding projects using horizontal directional drilling and trenchless methods
Superior Safety & Durability
→ Diffusion-tight steel jacket for corrosion and external protection
→ Long-life PUR foam insulation
→ Bitumen layer for added mechanical defense
→ Self-compensating, maintenance-free design
Outstanding Technical Performance
→ Exceptional resistance to high temperatures and pressures
→ Spiral corrugation for superior ventilation and reduced deposits
→ Verified by accredited labs with certified insulation performance
Efficient & Cost-Saving Installation
→ Lower civil engineering costs with reduced trench size
→ Faster installation with prefabricated continuous lengths
Operating Temperature: –170 °C to +150 °C (–274 °F to +302 °F)
Operating Pressure: 16 / 25 bar (232 / 362 psi)
Dimensions: DN 25–150 (1" – 6")
Carrier Pipe: Stainless steel (spiral corrugated)
Outer Pipe: Stainless steel
Thermal Insulation: Premium polyurethane (PUR) foam with bitumen protection
Proven Reliability and Maximum Efficiency
For heating water, domestic hot water, or steam condensate, the FLEXWELL-FHK delivers a highly durable piping system designed for modern district energy needs. Its robust construction, exceptional load capacity, and flexible installation options make it one of the most efficient and reliable solutions available.
Learn More & Get a Consultation
Contact us today — we look forward to supporting your project!
| Type | DN | Stainless steel inner pipe | External diameter | Min. bending radius | max. Delivery lengths* |
| d1 x s2 | D | ||||
| mm | mm | m | m | ||
| FHK 30/91 | 25 | 30.0 x 0.3 | 94 | 1.0 | 1000 |
| FHK 39/116 | 32 | 38.9 x 0.4 | 121 | 1.2 | 640 |
| FHK 60/148 | 50 | 60.0 x 0.5 | 156 | 1.5 | 590 |
| FHK 75/171 | 65 | 75.8 x 0.6 | 178 | 2.0 | 480 |
| FHK 98/171 | 80 | 98.0 x 0.8 | 178 | 2.0 | 480 |
| FHK 98/220 | 80 | 98.0 x 0.8 | 233 | 4.0 | 270 |
| FHK 127/220 | 100 | 127.0 x 0.9 | 233 | 4.0 | 270 |
| FHK 147/220 | 125 | 147.0 x 1.0 | 233 | 4.0 | 270 |
| FHK 200/310 | 150 | 197.5 x 1.2 | 313 | 6.0 | 230 |
