215 Diagnostics of Impulse Line Blockage with Differential Pressure Transmitter : Part 7: Blockage Diagnostics Using Phase Differences between Upstream and Downstream of Orifice

Abstract

Differential pressure transmitter with an orifice is widely used as a major field flowmeter. A major drawback of this flowmeter at the operation site is the blockage of the impulse line. Hence, applying the delay of pressure transmission to the differential pressure transmitter by this trouble, this paper develops a diagnostic method of the impulse line blockage with multi-sensing differential pressure transmitter. In this investigation, a diagnostic method using the shift of phase difference between upstream and downstream pressure of the orifice can diagnose the gradual impulse line blockage at the water and air line.