Diagnosis of impulse line blockage by frequency count approach

This paper proposes a novel method to diagnose a blockage of an impulse line. The blockage is the one of the most common trouble related to pressure transmitters, which are widely used devices for pressure measurement in process industry. To diagnose the trouble, some methods have been already developed. The most of the methods are based on the amplitude of pressure fluctuation, which is usually observed in flows. Instead of the amplitude, the newly proposed method utilizes frequency count of the fluctuation. The frequency becomes lower if the blockage exists, so that our method can diagnose the impulse line. The difference from the existing methods brings an advantage: a unique threshold can cover a wide range of process pressure. A new diagnostic index is developed based on the idea. An actual flow experiment was carried out and it proves the validity of our proposition.