GB/T 28880-2012 in English

《GB/T 28880-2012无损检测 不用电子测量仪器对脉冲反射式超声检测系统性能特性的评定》由TC122（全国试验机标准化技术委员会）归口，TC122SC1（全国试验机标准化技术委员会无损检测仪器分会）执行，主管部门为中国机械工业联合会。

Scope

This International Standard describes methods for evaluating the following performance characteristics of pulse-echo ultrasonic testing instruments: — horizontal limit and horizontal linearity; — vertical limit and vertical linearity; — resolution of incident face and rear face; — sensitivity and noise; — - the accuracy of the calibrated gain controller. The evaluation of these characteristics is mainly used for comparison between detectors, or by periodic retesting, to assess the long-term changes in the characteristics of a given detector, which may be a symptom of the detector will fail. If the variation exceeds the given limits, the detector requires calibration or maintenance. This standard can also be used to evaluate ultrasonic testing equipment using pulse train and A-type display (radio frequency or video). This method is suitable for workshop or field conditions, and does not require other electronic measuring instruments. This standard does not specify the limit value of the performance of the detection system. If such an acceptance index is required, it is the responsibility of the user to specify it. The acceptance criteria proposed in this standard are only used as an example, and the control documents of customers and end users contain more or less restrictive acceptance limits. The specified parameters to be assessed, the testing conditions and frequency, and the required reporting data shall also be determined by the user. This standard can be used to evaluate a complete detection system including probes, detectors, connectors, fixtures, and external alarm and auxiliary devices. It is mainly applicable to systems that do not change the system state or have no replacement parts for repeated use. This standard is not a substitute for calibration of the system used to test a given material. In addition to the detector being evaluated, the required testing equipment includes the selected reference test block and precision external attenuator (when specified). This standard also contains provisions on the application of assessment methods and the interpretation of assessment results. Alternative or other methods described in the examples in this standard shall only be used with the consent of the customer.