The patent-pending pipe-in-pipe design combines a corrugated stainless steel gas pipe with a yellow PE cover inside a V0 fire-rated corrugated sleeve in a slidable configuration. With 25+ DN40 FGLink fitting types available, an integrated earthing terminal and a free roll of silicone tape included with every spool, the DS-40 provides a practical solution for larger gas installation runs.
DN40 (40mm)
75m Spool
BSI Kitemark KM 598726
BS/EN 15266
Max operating pressure
0.5 bar
Applications & suitability
Commercial Gas Mains
Suitable for commercial contractors installing 40mm gas mains across larger sites.
Long Continuous Runs
The 75m spool supports long continuous pipe runs with fewer joints and reduced potential leak points.
Concealed Installation Routes
The built-in sleeve is designed for routes through solid walls, floors, screed, soil and unventilated voids.
Large Installation Projects
A 75m spool can support larger projects while helping minimise wastage through continuous runs.
Key specifications
| Manufacturer / MPN |
FlexiGas™ / DS-40-75 |
| Size |
DN40 (40mm) |
| Length |
75 metres – spool |
| CSST outer / internal diameter |
50mm / 41mm |
| Total maximum diameter including sleeve |
63mm |
| Maximum operating pressure |
0.5 bar (BS/EN 15266) |
| Tubing material |
1.4404 / 1.4541 stainless steel (BS/EN 10088) |
| Fire performance |
EN 1775 Annex A & B passed; jacket B-s1 d0, UV resistant |
| Certification |
BSI Kitemark KM 598726, EN 15266 |
| Colour |
Yellow |
| Warranty |
1 year (subject to manufacturer's T&Cs) |
Installation & compatibility
The FlexiGas DS-40 incorporates a built-in sleeve designed to meet the sleeve requirements referenced in BS 6891 and IGEM/UP/2, 3 & 7. This allows the pre-sleeved pipe to be installed through solid floors, solid walls, structural elements, earth or soil, screed, unventilated voids and unventilated risers without requiring additional sleeving on site.
The small annulus allows direct clipping, while the pipe-in-pipe construction features an inner corrugated stainless steel gas pipe and yellow PE cover inside a V0 fire-rated corrugated sleeve in a slidable configuration.
Design & performance benefits
Patent-Pending Pipe-in-Pipe Design
The inner corrugated stainless steel gas pipe sits within a yellow PE cover and V0 fire-rated corrugated sleeve in a slidable configuration.
Flexible Installation
The CSST pipe bends by hand, supporting continuous runs and helping reduce the number of joints required.
Flame-Free Installation
No soldering, sealants or specialist tools are required for forming the flexible pipe runs.
Secure Metal-to-Metal Seal
Compatible with the FlexiGas™ FGLink™ range, including more than 25 DN40 fitting types in dezincification-resistant brass.
Additional installation features
FG Bond™ Ready
Integrated earthing terminal certified to BS 951:2009 supports electrical bonding requirements.
Metre-Marked Tubing
Metre markings help with measuring and cutting pipe runs on site.
Silicone Tape Included
Every 75m spool includes one free roll of silicone tape for use with the installation.
Ideal for
Commercial Contractors
Designed for contractors installing 40mm gas mains across larger commercial sites.
Large Gas Installations
The 75m spool is suited to longer gas runs where continuous pipework is beneficial.
Plant Rooms & Larger Sites
Suitable for larger installation routes requiring 40mm flexible gas pipework and built-in sleeving.
Long Continuous Runs
Pairs with the FlexiGas spool roller, DS end caps and DN40 FGLink™ fittings for larger installations.
The FlexiGas 40mm Double Sleeved Flexible Gas Pipe DS-40 – 75m Spool provides a pre-sleeved DN40 gas pipe solution for larger commercial and high-demand gas installations. With its built-in sleeve, flexible CSST construction, BSI Kitemark certification, 75m spool length and compatibility with 25+ DN40 FGLink™ fitting types, it is designed to simplify long continuous gas pipe runs while reducing the need for additional sleeving, joints and specialist installation equipment.
