An eye on plugged lines
New technology detects impulse line plugging

Impulse line plugging of flow and level measurement instruments has long been an issue in many process applications, particularly where dense materials such as crude oil are being processed. Impulse line plugging can also be a problem in cold climates due to freezing. Identifying instruments that are suffering restricted or plugged impulse lines is very important since plugging can cause major process upsets or significant safety problems in various applications. The following article explains how these problems can be identified.
Process engineers like to have as much data as possible about the operation of their plant so that they can control it accurately and profitably, however, if a process instrument has impulse lines that become plugged or frozen the measured data can no longer be relied upon for accurate control. Although an experienced engineer will know about this problem the detection of plugged lines can be very difficult. As the lines plug, or freeze, pressure is trapped, this pressure is usually within the normal operating range of the process so the problem can remain undetected until a process upset occurs, compromising quality or safety. Now a technology developed by Emerson Process Management detects impulse line plugging in steady state processes where intelligent transmitters are employed.