DETECTING METHOD OF DEPOSIT IN HEAVY OIL STORAGE TANK

PURPOSE:To detect the deposit in a tank accurately and easily by detecting the reflected wave of an ultrasonic wave transmitted to the deposit in the tank and then measuring the required time from the transmission to the reception. CONSTITUTION:A transmitting and receiving sensor 4 transmits the ultrasonic wave to a reference point, e.g. 9a and measures the required time from the transmission of the ultrasonic wave to the reference point 9a the reception, and an arithmetic controller 5 calculates the acoustic velocity in oil by using the distance from the sensor 4 to the reference point 9a and stores the result in a storage device 6. Then, the sensor 4 measures the required time from the transmission of an ultrasonic wave to optional sludge 8 to the reception and the distance is calculated on the basis of said acoustic velocity in the oil which is stored in the storage device previously and stored in the storage device 6. Measurement points of the sludge 8 are changed successively to find the distribution state of the sludge 8.