FBOS – Foambag Operation On Stubs
In conjunction with Cadent Gas, SVI has developed a remote, live mains replacement technique for T1 stubs that delivers 100% abandonment.
Where a short length of T1 main has been left from a previous replacement scheme, the FBOS technique is able to remotely replace this section and fully decommission the annular space.
It is impractical to replace shorter lengths of T1 main which are often located in areas of engineering difficulty, for example, close to busy roads or junctions. However, the FBOS technique allows an excavation to be made in a non-sensitive area and from this remote position, the T1 main is replaced under ‘live’ conditions.
It is suitable for use on T1 mains, steel, ductile or cast iron and for dimensions of 75mm in 4” up to 125mm in 6”.
Benefits of FBOS
- Enables short sections of main, up to 30m to be replaced under ‘live’ conditions
- Can be used on one way fed mains
- Live head designed to negotiate bends, existing services and plugs
- The annular space of the old metallic main is fully decommissioned up to the final transition joint, avoiding the possibility of future leakage
- Ideal in traffic sensitive locations where access onto the main is restricted
- Replacement is undertaken from a remote location, typically 10-13 metres from where the pipe intersects with the parent main
- Trenchless Technology reduces environmental impact by minimising excavation and disposal of spoil
- Traffic Disruption is minimised