Why Process Gauges Must Resist Ambient Corrosion

Ambient corrosion is ever present in chemical, petrochemical and refining operations. Plant processes often involve the use corrosive materials that leak trace amounts into their nearby surroundings. Over time, even the lowest concentrations of these corrosive agents can damage nearby equipment and instruments such as process gauges.

Ambient corrosion typically attacks the internal components of a gauge, often causing the lens to cloud and/or damaging the pointer and internal components — any one of which makes it impossible to obtain an accurate local pressure reading.

In fact, real-world data from more than 300 Instrument Audits conducted by WIKA’s FAST team has identified corrosion as one of the most common reasons for gauge failure.

The case for sealed process gauges

To safeguard against failures from ambient corrosion processing plants should install gauges with NEMA 4X enclosures, which protect against such environmental rigors. Process gauges with Type 4X enclosures help to protect the instrument from corrosion as well as windblown dust and rain, splashing water and hose-driven water.1

FAST engineers often recommend WIKA’s XSEL® process gauges for such harsh operating conditions. XSEL® gauges with a membrane installed are completely weather-tight and fully compliant with the NEMA 4X “all weather” standard. The membrane prevents the ingress of corrosive media in the environment.

In addition to its suitability for measuring pressure of gaseous or liquid media in corrosive environments, the XSEL® process gauge with a liquid-filled case and a socket restrictor is available for applications with high dynamic pressure pulsations or significant vibration, which are also common reasons for gauge failure. The XSEL® also comes equipped with a solid front case and a safety-focused back blowout design.

If you have questions about the proper instrumentation for your applications, email WIKA’s FAST engineers. The FAST team has worked with more than 300 plants providing gauge expertise to help improve reliability and safety as well as cut costs.

1 Source: NEMA and IP Ratings

Leave a Reply