During the cleaning operation, pressurized cleaning solution is dispensed through a rotating nozzle assembly, which rotates in two axes. The axis are linked together in such a fashion that gradually, the whole inner surface of the tank is step by step cleaned. The sensor in the video is mounted on the top of the tank. This location is called the pole. The pictures below further explain the sensor mounting rules:
As the nozzles rotate, the spray pattern creates a unique family of sound waves creating an acoustic signature unique to the tank dynamics that are detected from the exterior of the tank with a microphone. The picture below shows the signal acquired:
Each time the spray passes close the sensor, the sensor detects a spike. From the frequency of these spikes and their magnitude, the spray impact force and the cleaning head rotation frequency are calculated. A “learn” cycle is performed on a known good cleaning cycle to establish reference values for the two key parameters. This approach allows the use of the system on any tank shape, location, material etc...
During subsequent cleaning cycles, the same key parameters
are extracted and compared to the reference values. For
each parameter a separate deterministic alarm condition can
be defined. The picture below shows the detailed report screen from Cip Explorer after the compare cycle.
The green lines are the reference cycle and the blue lines show the compare cycle. The series are compared by strict upper lower limits or by histograms.
Back to Home | Next: System Configuration