A large multinational company approached MTI Instruments to provide a capacitive sensing system that could inspect blade tip clearance through existing inspection ports in a steam turbine case. The inspection ports had pre existing threads, so MTII’s probes had to fit a specified diameter.
MTII had to also be able to accurately sense the clearance to the manufacturers specially shaped blade tips.
MTI’s Digital Accumeasure TM is ideal for this type of application because very small probes can be mated to the amplifier, then digitally corrected for high accuracy (linearity) at what would previously have been considered too large a working gap with older analog capacitive products. MTI designed a special probe configuration to fit into the inspection port.
Analysis at MTI Instruments’ facility ensured that the probe could properly detect the narrow blade with no chance that it would be struck. After customer review of the data, they subsequently purchased the systems. Utilizing a MODBUS output interface, the customer was able to forward tip displacement results right to the maintenance engineer’s smart phones!