Well Logging Transducer Matches The Calculation Of Parameters And Logging Location Laying

In recent years, with the development of the oil well drilling technology, the depth of oil well is gradually increased and the automation instrument level is also enhanced. And then, the liquid flowmeters with the characters of more precision, stabilization, convenience and cheapness are needed, as the traditional measuring instruments have not keep up with the drilling technology developments. Ultrasonic flowmeter is one of the faster-growing technologies within the general field of instruments for process monitoring, measurement and control. However, many problems, such as acoustic matching between the ultrasonic sensor and petroleum in casing pipe, laying of sensor in casing pipe, sending and receiving of acoustic wave accurately, error correction between measuring parameters and real parameters, etc, should also been investigated.The flowmeters measuring theory is that the sound can bring the information of the liquid velocity when transmitting in the liquid, and then using simple reliable calculated method and signal processing technology, the velocity of liquid is obtained.The measuring principle of ultrasonic flowmeters and the structure of ultrasonic transducers have been introduced in this paper. The sending and receiving principle of ultrasonic sensor and the sound transmission-path have also been analyzed. According to the acoustic transfer matrix, the influence of characteristic impedance and thickness of acoustic matching layers has been calculated for monolayer and multilayer matching. The matching effect has also been accurately calculated via computer programs, and multi-group optimum matching thicknesses have been given in the paper, which is useful to the actual designing of ultrasonic sensor.Acoustic oblique incidence technology has been chosen to meeting the need of oil flow velocity detecting in casing pipe, and total reflection angles of sound in oil well's wall have been calculated. Changing the distance of ultrasonic sensor placement, the oil velocity and acoustic emission angle have also been obtained. Reasonable placement distances of the acoustic sensors have been given, and have been also designed, whichhave been used in underground survey and service for engineering.Compared with traditional flowmeter, ultrasonic flowmeter have manyoutstanding characters, for example low cost, high precision, simple installation and measurement, not affected production, and realizable on line detection. The need of underground petroleum flow measurement can be excellently contented, and the measurement difficulties of present technical in petroleum flowrate measuring field can also be solved.