Corrosion Proof Vibrating Wire Piezometer

Overview

The RST Corrosion Proof Vibrating Wire Piezometer VW2190 and VW2191-series are specially designed for extreme corrosive environments including use under demanding acidic geotechnical conditions, such as in heap leach mineral processing facilities. They provide excellent long-term accuracy and reliability.

Vibrating Wire Piezometers (VWP) are the electrical piezometers of choice for geotechnical monitoring as the frequency output of VW devices is immune to external electrical noise and able to tolerate wet wiring common in geotechnical applications. The VW2190/VW2191-series VW piezometers use the same measuring principle as a standard VW2100-series piezometer but differs in that the VW2190/VW2191-series have more robust body designs that resist corrosion damage – this includes differences in housing construction, signal cable choice and additional acid resistant protection.

The VW2190 and VW2191 piezometers consist of heavy duty VW transducers (316 stainless steel body), bladders filled with glycol solution and PVC housing to protect the bladder. In highly acidic groundwater conditions, corrosion can occur on the sensitive diaphragm of the pressure transducer within a standard VW2100-series piezometer. The VW2190 and VW2191 prevent the occurrence of corrosion damage by isolating the transducers within a glycol solution filled bladder.

For acidic conditions, signal cable model EL342202 (2 pair 22 AWG OSD orange HDPE jacket 0.25”ø) is used to resist extreme acidic attack and to ensure lasting monitoring information and must be used with models VW2190 and VW2191. HDPE was specifically selected due to its resistance to acid.

A final layer of anti-corrosive protection is applied to the outside of the assembly and consists of petrolatum, UV resistant and solvent-free tape on all exposed stainless steel surfaces. An additional shield made of heat shrink adhesive ensures long-term functionality.