If the threat of blockage is real but likely to be infrequent, perhaps it is sufficient to be warned when it is occurring or has occurred. In that case an ABB compact DP flowmeter fitted with our 266-series DP or multivariable transmitter is ideal. Within the transmitter itself is a diagnostic called PILD - Plugged Impulse Line Detection. This monitors the signal patterns in each tapping and recognises the deviations in pattern caused by partial or complete blockage, and gives an alarm.
If the application is such that it is likely to block frequently, then an ABB Wedge meter can be supplied, with tappings suitable for connection to a DP transmitter fitted with wafer-type (or even chemical tee) remote seal elements. These have no small bore impulse lines to become blocked and retain the fluid entirely within the meter body.