A BRUGG GROUP COMPANY
Pipe System for DEF (Diesel Exhaust Fluid)
NIROFLEX is a moderately priced, single-wall carrier pipe made of seamless, helically corrugated stainless steel with a PE jacket. One of the primary uses of this pipe is DEF and other below ground applications, where UL approval is not required. the fact that the PE jacket is UV protected makes this pipe also ideal for above ground installations. This pipe is easy to handle and install. It is manufactured in “endless” lengths, which eliminates connections (potential leak points) between beginning and end.
Technical Specifications and Material Options
NIROFLEX is available in several stainless steel grades and configurations to meet different project requirements:
✅ Stainless steel grades: 1.4301, 1.4404, 1.4571, 1.4539
✅ Nominal diameters: DN 20–150
✅ Pressure ratings: PN 6 / PN 16 (depending on pipe size)
✅ Long, continuous pipe lengths – minimal joints, fewer leak points
The NIROFLEX CNT version features an LDPE protective casing for underground installations. Thanks to its UV-resistant PE jacket, the pipe is also ideal for above-ground use. It is lightweight, flexible, and easy to install without welding or special tools.
A key application of NIROFLEX is the safe and efficient transport of Diesel Exhaust Fluid (DEF) in fueling systems and storage installations. As of January 1, 2010, the EPA's Regulation 2010 mandates that diesel vehicles significantly reduce nitrogen oxide (NOₓ) emissions. To comply, most trucks are equipped with Selective Catalytic Reduction (SCR) systems.
SCR technology converts harmful NOₓ into harmless nitrogen using a catalyst and a special solution – Diesel Exhaust Fluid (DEF) – which is:
Because of its chemical resistance and durability, NIROFLEX stainless steel pipe is ideally suited for DEF line systems – particularly in underground applications where UL approval is not required. Its corrosion resistance and “endless” design minimize leak risk and ensure long-term performance.
In addition to DEF transport, NIROFLEX is used in a variety of industrial applications where a flexible and durable corrugated pipe is required:
✅ Liquid transport in industrial plants
✅ Heat exchanger systems
✅ Protective piping solutions in complex installations
The corrugated design ensures excellent flexibility and allows easy routing even in confined spaces.
Whether for DEF infrastructure, transporting liquids, as a protective pipe or as a heat exchanger pipe, NIROFLEX offers a reliable, corrosion-resistant stainless steel pipe solution with superior installation flexibility and durability. Its seamless, helically corrugated pipe structure ensures maximum performance with minimal maintenance.
| Type | Nominal diameter | Volume Inner pipe | Weight |
| mit PE | DN | dm3/m | kg/m |
| CNT 22/31 | 20 | 0,37 | 0,44 |
| CNT 30/39 | 25 | 0,8 | 0,56 |
| CNT 39/49 | 32 | 1,3 | 0,9 |
| CNT 48/60 | 40 | 1,37 | 1.37 |
| CNT 60/71 | 50 | 3 | 1,75 |
| CNT 98/120 | 80 | 8,4 | 4,5 |
| CNT 127/152 | 100 | 14,3 | 6,6 |
| CNT 147/172 | 125 | 17,3 | 8,3 |
| CNT 200/230 | 150 | 23,2 | 12,7 |
| Type | Nominal diameter | Volume Inner pipe | Weight |
| ohne PE | DN | dm3/m | kg/m |
| CNW 22/25 | 20 | 0,37 | 0,3 |
| CNW 30/34 | 25 | 0,8 | 0,4 |
| CNW 39/44 | 32 | 1,3 | 0,63 |
| CNW 48/55 | 40 | 2 | 1 |
| CNW 60/66 | 50 | 3 | 1,24 |
| CNW 75/86 | 65 | 5,12 | 1,9 |
| CNW 98/109 | 80 | 8,4 | 3,5 |
| CNW 127/143 | 100 | 14,3 | 4,75 |
| CNW147/163 | 125 | 17,3 | 6 |
| CNW 200/220 | 150 | 23,2 | 9,5 |
NIROFLEX is a flexible corrugated stainless steel piping system for transporting liquids and gases, as well as for numerous applications in industry and energy technology. Thanks to its helically corrugated pipe geometry, NIROFLEX combines high flexibility with corrosion resistance and enables installation even along challenging routes.
The corrugated stainless steel pipe is used, among other applications, as a carrier pipe, protective pipe, conduit, heat exchanger tube, or liner for existing piping systems. Different materials and pipe designs are available depending on the application. NIROFLEX is also available with an outer protective jacket for underground installation.
The special characteristics of NIROFLEX result from the combination of corrosion-resistant stainless steel materials and the helically corrugated pipe design. This enables flexible pipe routing and helps accommodate temperature-related changes in length. At the same time, the pipe profile is optimized for flow characteristics and heat transfer.
The combination of these characteristics makes NIROFLEX a versatile solution for industrial piping, plant construction, and applications in energy technology.
NIROFLEX is used for a variety of transport and installation tasks. Depending on the design and operating conditions, the flexible corrugated stainless steel piping system is suitable for transporting liquids and gases above and below ground. It can also be used as a protective pipe, conduit, or heat exchanger tube.
Industrial liquid and gas transport
In industrial applications, NIROFLEX serves as piping for various liquid and gaseous media. The corrosion-resistant stainless steel materials allow application-specific design. Which media can be transported depends particularly on the choice of material, the chemical composition of the medium, and the relevant temperature and pressure conditions.
Heat exchanger tube and hot water heat tracing
NIROFLEX can be used as a heat exchanger tube, for example in vessels and tanks. The helically corrugated pipe geometry is optimized for heat transfer and flow characteristics. It promotes turbulence and increases the surface area available for heat exchange. This can improve heat transfer between the media involved.
Another application is hot water heat tracing. The appropriate pipe size and design depend on the technical requirements of the respective system.
Protective pipe, conduit, and liner
In addition to transporting media, NIROFLEX can be used as a conduit for installing cables or piping, as a protective pipe, or as a liner for other piping systems. Its high flexibility makes it easier to adapt to the intended pipe route.
NIROFLEX for biogas and solar installations
NIROFLEX is also suitable for various applications in installations for generating and using renewable energy, such as biogas and solar installations. The corrugated stainless steel piping system can be used to transport biogas and heat transfer fluids, among other media.
In these applications, media resistance and the permissible temperature and pressure conditions are crucial. NIROFLEX is available in different stainless steel grades and pipe designs, allowing the system to be configured for the respective operating conditions.
Particularly in heat transfer applications, the corrugated pipe geometry, optimized for thermal and flow characteristics, offers design advantages. The actual heat transfer performance depends on the design and operating conditions of the respective system.
NIROFLEX is manufactured in long lengths at the factory and can be supplied on reels or in coils. The pipes can be installed directly from the reel or coil and cut to the required length at the jobsite.
Thanks to its high flexibility and tight bending radii, the corrugated stainless steel pipe can also be installed along challenging routes. Existing utilities and other obstacles can be taken into account when planning the pipe route. Long continuous pipe sections reduce the number of joints required and can decrease installation work.
Another design advantage is self-compensation: The helically corrugated pipe geometry allows thermal changes in length to be accommodated. This makes NIROFLEX suitable for applications where temperature-related expansion must be taken into account.
The flexible piping system consists of a helically corrugated inner pipe made of stainless steel. The standard stainless steel grades used are 1.4301, 1.4404, and 1.4571. Grade 1.4539 is also available for project-specific applications.
NIROFLEX is available in different nominal sizes and pressure ratings. NIROFLEX product family variants
The appropriate NIROFLEX version is selected according to the intended medium, pressure and temperature conditions, and requirements relating to installation, corrosion protection, and, where necessary, thermal insulation.
Various connection and joining technologies are available for NIROFLEX. The selection depends on the pipe size, the application, and the requirements of the joint.
One option is the flameless GRAPA-S connection technology. This is based on graphite sealing technology and enables joints to be made without on-site welding. The modular connection system includes various components for connections to standardized fittings.
Depending on the version, connections with weld ends, external threads, or flanges are available. Flameless connection technology can be particularly advantageous in applications where on-site welding is to be avoided, for example in potentially explosive atmospheres. The suitability of the respective connection technology must be assessed against the specific operating conditions.
We are pleased to assist you in selecting and designing the appropriate NIROFLEX piping system for your project. In addition to manufacturing and testing, our services include technical planning and advice on materials, pipe sizes, designs, and connection technologies.
For practical applications, we regularly offer theoretical and practical seminars at our training center in Wunstorf. These are aimed, among others, at specialists in industrial piping and tank construction.