NPC-3000 Series NATM Pressure cells are designed to monitor radial and tangential stresses of shotcrete in the construction of tunnels, particularly those using the New Austrian Tunnel Method and other underground works. The cells are constructed from two stainless steel plates welded around their periphery with the narrow gap between the plates filled with hydraulic fluid. As the stress increases within shotcrete or concrete the fluid pressure within the cell rises as the plates are squeezed together. A length of stainless steel tube connects the plates to a pressure transducer that converts the pressure to an electrical signal which can be read directly with a readout or data logged.  
Range: 2, 3, 5, 7, 20, 35 MPa
Over range: 150% FS
Resolution: ± 0.025% FS
Accuracy: ± 0.1% FS
Non-linearity: <0.5% FS
Cell dimensions: 100 x 200mm, 150 x 250mm
Cell thickness: 5mm
Operating temp: -20°C to +80°C

Geosense Ltd
Nova House
Rougham Industrial Estate
Rougham, Bury St Edumunds
Suffolk IP30 9ND
ENGLAND
T +44 (0)1359 270457
F +44 (0)1359 272860
info@geosense.co.uk