GENEQ > Materials testing > Pressure Cells
| Radial and Tangential Pressure Cell |
| These total pressure cells from Interfels are designed to monitor radial or tangential stress in tunnel linings. |
| OPERATION |
Total pressure acting
on the sensitive surface of the cell is transmitted to the oil inside
the cell and measured by a VW pressure transducer. A vibrating wire
readout or data logger excites the transducer and stores a reading
in Hz. Calibration factors are applied to the reading to arrive at
a pressure in bar or psi. |
| SHOCRETE INSTALLATION |
|
Radial cells are placed at the interface between
the excavated ground surface and the shotcrete lining. Tangential
cells are attached to the reinforcing cage or to some other support
so they will be embedded in the shotcrete lining. After the cells
are tied into place, shotcreting takes place. After the shotcrete
cures, tangential cells are pressurized by crimping the cell’s
pressurization tube, which forces oil from the tube into the cell.
The influx of oil causes the cell to inflate, forcing the sensitive
side of the cell into contact with the surrounding shotcrete material. |
| PRECAST INSTALLATION |
| Cells can be cast directly into lining segments at the casting yard. |
| ADVANTAGES |
| Superior Construction |
|
Cells are made from two oval stainless
steel plates. The edges of the sensitive top plate are turned over
the base plate and laser welded to form a sealed cavity, which is
later filled with deaired oil. This construction minimizes tangential
stiffness and prevents stiff weld joints and sharp edges. |
Small Height
to Width Ratio |
|
The small height to width ratio
of the cell provides superior performance, even in stiff media such
as concrete. |
VW Sensor |
|
The VW pressure sensor eliminates
hydraulic lines and provides consistent readings in harsh environments. |
Manual or Automatic
Readout |
|
The VW transducer can be read
manually with a vibrating wire readout or automatically with a data
logger. |
| SPECIFICATIONS | |
| Tangential cell | |
| Sensor Type | Vibrating wire |
| Sensor Range | 200 bar. Lower pressure ranges are also available |
| Sensor Resolution | 0.025% FS |
| Sensor Accuracy | ±0.5% FS |
| Size | 222 x 101 x 3.5 mm (8.75 x 4 x 0.14 in.) |
| Pressurization Tube | 400mm (16 in.) long |
| Radial Cell | |
| Sensor Type | Vibrating wire |
| Sensor Resolution | 0.025% FS |
| Sensor Accuracy | ±0.5% FS |
| Size | 283 x 151 x 3.5mm (11 x 6 x 0.14 in.) |
| CAT. NO. | DESCRIPTION |
| Tangential Cell | |
| SI52608270 | Tangential Cell, 200 bar (3000 psi) |
| SI50613524 | Signal cable |
| Radial Cell | |
| SI52608260 | Radial cell, 3.5 bar (50 psi) |
| SI52608262 | Radial cell, 7 bar (100 psi) |
| SI52608264 | Radial cell, 17 bar (250 psi) |
| SI52608266 | Radial cell, 35 bar (500 psi) |
| SI52608268 | Radial cell, 70 bar (1000 psi) |
| SI50613524 | Signal cable |