Process measurements in corrosive environments caused by saltwater or salt in air

 
One of the primary challenges facing field instrumentation in offshore and marine applications is the corrosive nature of the environment in which they are installed.

These harsh conditions mean that standard instrument housings such as aluminum, for example, can quickly corrode and potentially affect ongoing instrument performance and safety. Salt water, for instance, can act as an electrolyte and potentially promote galvanic corrosion in such circumstances.

 

It is generally accepted, therefore, that in applications where exposure to these risks is likely, that stainless steel enclosures are used for relevant field instruments. Field instruments measuring temperature, pressure, level and flow, for example, will all be exposed to the elements/atmosphere when installed aboard ships or oil platforms.

 

Temperature measurement using the PR 7501 with a stainless steel housing

Oily bilge water, a mixture of water, oily fluids, lubricants and grease, cleaning fluids, etc., often can accumulate in the lowest part of large ships. In order to discharge and store the bilge water responsibly, it is processed through an oil/water separator. Prior to this process, the bilge water is often heated to over 49°C to allow for optimum oil separation. The PR 7501 with a stainless steel housing can give highly visible local indication of the water temperature together with 4…20mA output to the bilge pump control system.