Flexible flue liners SF / DF
Solution for the renovation of existing chimneys
Flexible liners SF / DF is a stainless steel system designed for renovation of existing brick and concrete chimneys, when rigid liners cannot be installed due to the curvature of the chimney or more complex geometry. This category is especially relevant in renovation projects, when it is important not only to renew the smoke exhaust channel, but also to adapt to the actual condition of the existing chimney. The system is produced in 60, 80, 100, 110, 120, 125, 130, 150, 160, 180, 200, 250 and 315 mm diameters, so it can be adapted to different objects and various types of heating devices.
SF and DF types for different needs
This category consists of two main solutions - SF and DF, as well as their versions with a seal. SF is a single-layer flexible liner, and DF is a double-layer flexible liner. Both types allow you to choose a solution based on the technical logic of the project, the desired design and operating conditions. This structure provides more flexibility, as the user can choose not only by diameter, but also by the type of insert, its design, and the system's operating mode.
Technical features and materials
The SF and DF versions without a seal are suitable for gaseous, liquid and solid fuels, operate up to 600 °C and belong to the N1 natural draft class. The sealed versions are designed for gaseous or liquid fuels, can operate up to 200 °C and are suitable for P1 positive pressure systems. All systems are suitable for operation in humid conditions. SF is made of stainless steel strip EN 1.4404, the thickness of which is 0.12 mm, while DF has an inner wall made of EN 1.4404 and an outer wall made of EN 1.4301, the thickness of the strips in both layers is 0.10 mm. The natural draft versions are resistant to soot ignition, while the sealed versions are not resistant.
Flexibility for more complex installation situations
The greatest value of SF / DF flexible inserts is their ability to adapt to more complex chimney geometries. When the shaft is not perfectly straight, has offsets or other installation restrictions, a flexible insert allows for a more reliable formation of a continuous smoke exhaust channel. This makes this system a very practical alternative in cases where rigid inserts would be difficult to fit or could not be installed at all. Such adaptability is especially important in renovation works, where real conditions often differ from standard solutions.
Transitions and system compatibility
Additional transition solutions are also offered for this category, helping to integrate the system into a wider chimney assembly. Among them is the transition from flexible to rigid insert, which allows for more convenient connection of different system types in one project. This provides more freedom in planning the renovation solution and helps to maintain a consistent logic of the entire system from the flexible insert to other connected elements.
Why choose SF / DF
If you are looking for a solution that combines flexibility, stainless steel quality, a wide range of diameters and adaptability to renovation, flexible inserts SF / DF are a very strong choice. This is a system that allows you to reliably renew an existing chimney in more complex conditions and form a technically consistent smoke exhaust channel according to the real needs of the facility. When choosing a specific solution, it is important to assess the type of heating device, draft mode, chimney geometry and the necessary additional transition elements.
