The project at a glance
The 2.4 km long tunnel, which will connect Saint-Genis-Laval (Hôpitaux Sud) to Gare d'Oullins station by 2023, the current terminus of metro line B (in the South of Lyon), began at the end of 2019. The tunnel boring machine (TBM) of the German manufacturer Herrenknecht, after assembly, digs the ground at a rate of about 200 metres per month. Our after-sales service (SAV) took care of commissioning and adjusting the control valves installed on this underground machine at the end of 2019.
"Critical" SAMSON valves on the tunnel boring machine
The 122-metre long TBM has a 9.5-metre diameter cutting wheel at the front. To dig the tunnel, the clayey bentonite mud is sent under pressure to the front of this wheel to plug the subsoil and ensure its stability. Our Type 3241 control valves are responsible for maintaining compressed air pressure at this cutting wheel.
SAMSON devices in detail
SAMSON equipments provide a pneumatic control loop (1 operating and 1 safety loop). Each loop is composed of:
- a compressed air inlet valve and an exhaust valve (type 3241)
- a pneumatic controller
- des positionneurs pneumatiques (types 4765)
- a position feedback on each valve
- pneumatic actuators (type 3271)
- a pneumatic transmitter (type 3804)
- a pressure reducing valve (type 41-23), installed upstream of the inlet valve