'Ultrasonic Power Measuring Instruments Verification System Form' Released for Solicitation of Comments

On October 24, the National Acoustics Measurement Technical Committee issued the 'Ultrasonic Power Measurement Instrument Verification System Table' for soliciting comments. Now it is soliciting comments from the society. Feedback email: xinggz@nim.ac.cn.　　 Since the release of JJG 2050-1990 'Ultrasonic Power Measurement Instrument Verification System TableHowever, with the development of ultrasound diagnosis, physiotherapy and treatment instruments, the demand for high-frequency and high-power value traceability is increasing, and the original calibration system table needs to be revised.　　This verification system table is compiled in accordance with JJF1104-2003 'National Metrological Verification System Table Compilation Rules'.　　This verification system table replaces JJG 2050-1990 'Ultrasonic Power Measuring Instruments'. Compared with JJG 2050-1990, the main technical changes are as follows: Modified the description of the frequency range of the milliwatt ultrasonic power reference and the secondary reference device, and expanded the frequency range (0.5 ~ 10) MHz to (0.5 ~ 25) MHz; modification The description of the frequency range of the watt-level ultrasonic power reference and the secondary reference device is added, and the frequency range (0.5 ~ 10) MHz is modified to (0.75 ~ 5) MHz; a new watt-level ultrasonic power reference device based on the buoyancy change calorimetry method is added , The frequency range is 0.75 MHz ~ 5 MHz, the ultrasonic power range (20 ~ 200) W uncertainty is 5% (ku003d2). The high-frequency frequency expansion of the milliwatt-level ultrasonic power benchmark and secondary benchmark in this verification system has been verified by the international key comparisons CCAUV.U-K3, CCAUV.U-K3.1 and APMP.AUV.U-K3; The frequency range modification of the watt-level ultrasonic power benchmark and the secondary benchmark has been verified by the international standard IEC 61161 and previous comparisons and actual usage; 3.3 the revision based on the buoyancy change calorimetry method has been supported by the international standard IEC 62555, and China NIM, UK NPL research experiment verification. Ultrasonic power measurement benchmark is used to reproduce and save the unit value of ultrasonic power in the 0.5 ~ 25 MHz frequency band, and transfer the value to the working measurement instrument through the ultrasonic power measurement standard instrument to ensure the accuracy and uniformity of the domestic ultrasonic power value .　　 The unit of ultrasonic power value is watt (W).　 Ultrasonic power measurement standards include milliwatt-level ultrasonic power reference devices and secondary reference devices that adopt the radiation force balance method, watt-level ultrasonic power reference devices and secondary reference devices of the radiation force balance method, and watt-level ultrasonic power reference devices of the calorimetric method.　 The ultrasonic power values u200bu200bbetween the milliwatt-level ultrasonic power reference and the secondary reference device, and the watt-level ultrasonic power reference and the secondary reference device are directly compared through a standard ultrasonic transducer.　　 This calibration system table is suitable for the transmission of ultrasonic power measuring instruments in the frequency band of 0.5 ~ 25 MHz. It stipulates the measurement value transmission procedure, measurement value transmission method and measurement uncertainty between the ultrasonic power reference and the secondary reference through the ultrasonic power measurement standard to the working measuring instrument. When carrying out calibration, it can also be used as the basis for the traceability of the value (reprinted information, infringement is deleted)