Pneumatic Piezometer

Pneumatic Piezometer

Brand : Slope Indicator – USA

Aplikasi penggunaan :

Pneumatik piezometer digunakan untuk mengukur tekanan air pori di tanah jenuh.:

• Memantau tekanan air pori untuk mendeteksi keamanan dari suatu timbunan atau ekskavasi.
• Memantau tekanan air pori untuk mendeteksi stabilitas kemiringan.
• Memantau efek dari sistem dewatering yang digunakan untuk ekskavasi.
• Memantau efek pengembangan bawah tanah seperti saluran vertikal dan aliran pasir.
• Memantau tekanan air pori untuk memeriksa performa dari timbunan atau suatu bendungan.
• Monitoring pore water pressures to check containment systems at land fills and tailings dams.

Advantages

Slope Indicator’s pneumatic piezometers employ a simple and reliable transducer that is free from zero drift. Long term performance is enhanced by corrosion-resistant plastic construction, polyethylene tubing, and in-line filters in all connectors. Compatible with both flow and no-flow reading techniques.

Operating Principle

In a typical installation, the piezometer is sealed in a borehole, embedded in fill, or suspended in a standpipe. Twin pneumatic tubes run from the piezometer to a terminal at the surface. Readings are obtained with a pneumatic indicator.

The piezometer contains a flexible diaphragm. Water pressure acts on one side of the diaphragm and gas pressure acts on the other. When a reading is required, a pneumatic indicator is connected to the terminal or directly to the tubing. Compressed nitrogen gas from the indicator flows down the input tube to increase gas pressure on the diaphragm.

When gas pressure exceeds water pressure, the diaphragm is forced away from the vent tube, allowing excess gas to escape via the vent tube. When the return flow of gas is detected at the surface, the gas supply is shut off.

Gas pressure in the piezometer decreases until water pressure forces the diaphragm to its original position, preventing further escape of gas through the vent tube. At this point, gas pressure equals water pressure, and the pneumatic indicator shows the reading on its pressure gauge.

Spesifications :

PNEUMATIC PIEZOMETER
– Sensor Type: Twin-tube pneumatic transducer.
– Range: Pressure rated for 27.5 bar or 400 psi. Working range depends on gauge supplied with pneumatic indicator.
– Gauge Accuracy: ±0.25% FS.
– Diaphragm Displacement: 0.01 ml typical.
– Filter: Sintered stainless steel, 50 micron pores.
– Materials: ABS and PVC plastic body, synthetic rubber diaphragm.
– Diameter: 25.4 mm (1″).

Ordering Info :

PIEZOMETER ONLY
Pneumatic Piezometer . . . . . . . . .51417800
Part number includes only piezometer. Tubing is attached to piezometer at factory and must be ordered at same time as piezometer.

PIEZOMETER WITH TUBING
Piezometer & 50’ of tubing . . . . . .51417801
Piezometer & 100’ of tubing. . . . .51417802
Piezometer & 150’ of tubing. . . . .51417803
Piezometer & 200’ of tubing. . . . .51417804
Order numbers specify a pneumatic piezometer with tubing and quick-connect plug. These piezo-meters are stocked for faster delivery.

TUBING & CONNECTORS
Twin Tubing . . . . . . . . . . . . . . . . . 51416900
Two polyethylene tubes bundled in polyethylene jacket.
Tubing Size: 4.76 mm with 1 mm wall (3/16″with 0.04″ wall).
Jacket: 12 mm x 7 mm with 1.1 mm wall (0.46″ x 0.28″ with 0.045″ wall).
Burst Pressure: 3.4 MPa (500 psi).
Minimum Bending Radius: 75 mm (3″).
Tubing Buoyancy: 0.021 kg per m (0.014 lb per foot).
Weight: 0.06 kg per meter (0.04 lb per foot).

Splice Kit . . . . . . . . . . . . . . . . . . . 51401723
Includes 3 brass unions, self-vulcanizing mastic pad, and sealing tape.

Quick Connect Plug . . . . . . . . . . . 51407302
Brass quick-connect fitting for input tube. Plug includes in-line filter and 90° elbow for insertion into panel.

PNEUMATIC INDICATOR
With 0.25% Analog Gauge. . . . . . 51425601
With 0.25% Digital Gauge . . . . . . 51425602
See separate datasheet for details.