1.1 本规程描述了使用相控阵超声波方法检查焊缝的超声波技术（参见 注1 和 注释2 ). 1.2 本规程主要针对对接焊缝和三通焊缝，在S扫描或E扫描模式下使用角梁。如果有足够的覆盖范围和技术记录并得到批准，可以使用本规程检查替代焊接技术，例如固态粘接（例如，搅拌摩擦焊）和熔焊（例如，电子束焊接）。不包括点焊等特定几何形状的实践。本规程旨在用于9至200 mm的厚度。如果可以证明该技术能够在相同壁厚和几何形状的实体模型上提供足够的检测，则可以使用本规程检查较大和较小的厚度。 1.2.1 当试图使用相控阵确定指示尺寸时，应格外小心。 如果没有适当的程序，由于光束发散、多个虚拟探头从同一指示返回信号等，指示可能会过大。有关更多指导，请参阅 12.4 . 1.3 单位- 以国际单位制表示的数值应视为标准值。 注1: 本实践基于铁和铝合金的经验。如果可以制定参考标准来证明超声波束可以成功穿透特定材料和焊缝，则可以使用本规程检查其他金属材料。 注2: 有关其他相关信息，请参阅ASME BPVC第五节第4条指南 E2491 实践 E317 ，并练习 E587 . 1.4 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.5 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 相控阵超声检测（PAUT）是一种先进的检测技术，与使用单元件传感器的传统UT相比，它用于增强缺陷检测、尺寸确定和成像。PAUT利用多元件（阵列）探头，其中每组元件以预先计算的时间延迟（“聚焦定律”）对每个元件进行脉冲（“相位”）。由此产生的建设性干扰和破坏性干扰允许电子转向、整形和聚焦声束。 5.2 虽然相控阵主要是一种产生和接收超声波的方法，但也是一种扫描和成像方法。 两种基本的扫描类型是线性或电子扫描（E扫描）和扇形或方位扫描（S扫描）。在模拟手动扫描的E扫描中，以相同的折射角度创建多个声束。通过在探头内的有源元件组一端依次添加一个元件并从另一端掉落一个元件，通过仪器的车载处理器协调时间多路复用，沿阵列的有源轴对波束进行电子平移。在相控阵独有的S扫描中，声束通过顺序更改应用于每个元件的延时，以电子方式扫过一系列用户定义的角度。由于光束角度不再完全取决于楔形角度，因此与传统UT相比，可以获得更完整的数据，并可以检查更复杂的几何形状。 由于其独特的特性和能力，相控阵需要特殊的设置和标准化，如本实践所述。商业软件允许操作员在不详细了解相位要求的情况下轻松进行设置。 5.3 相控阵可以以不同的方式使用:手动或编码线性扫描；以及不同的显示器或显示器组合。在手动扫描中，主要显示为S扫描和相关A扫描。S扫描比E扫描具有优势，因为可以同时覆盖所有指定的检查角度。 5.4 使用相控阵进行超声波焊接检查的主要优点是: 5.4.1 增强了对光束特性的控制，包括聚焦和控制光束的能力； 5.4.2 由于在一次扫描中获得和显示了多条线/角度，因此扫描速度更快，检测概率更高； 5.4.3 提高了检查复杂几何形状和访问受限区域的能力； 5.4.4 从真实深度S扫描获得更好的成像； 5.4.5 数字数据存储能力，旨在对不同检查的数据进行审计、归档、离线后处理、重新处理和比较； 5.4.6 使用电子仪器进行快速且可重复的设置。

1.1 This practice describes ultrasonic techniques for examining welds using phased array ultrasonic methods (see Note 1 and Note 2 ). 1.2 This practice uses angle beams, either in S-scan or E-scan modes, primarily for butt welds and Tee welds. Alternative welding techniques, such as solid state bonding (for example, friction stir welding) and fusion welding (for example, electron beam welding) can be examined using this practice, provided adequate coverage and techniques are documented and approved. Practices for specific geometries such as spot welds are not included. The practice is intended to be used on thicknesses of 9 to 200 mm. Greater and lesser thicknesses may be examined using this practice if the technique can be demonstrated to provide adequate detection on mockups of the same wall thickness and geometry. 1.2.1 Extreme caution should be used when attempting to size indications using phased array. It is likely that without proper procedures, indications can be oversized due to beam divergence, multiple virtual probes returning signals from the same indication, etc. For more guidance, see 12.4 . 1.3 Units— The values stated in SI units are to be regarded as standard. Note 1: This practice is based on experience with ferrous and aluminum alloys. Other metallic materials can be examined using this practice, provided reference standards can be developed to demonstrate that the particular material and weld can be successfully penetrated by an ultrasonic beam. Note 2: For additional pertinent information, see ASME BPVC Section V, Article 4, Guide E2491 , Practice E317 , and Practice E587 . 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 Phased array ultrasonic testing (PAUT) is an advanced examination technique used for enhanced flaw detection, sizing, and imaging as compared to conventional UT employing single-element transducers. PAUT utilizes multi-element (array) probes in which groups of elements are pulsed with pre-calculated time delays (“focal laws”) for each element (“phasing”). The resulting constructive and destructive interference allows for electronic steering, shaping, and focusing of the sound beam. 5.2 Though primarily a method of generating and receiving ultrasound, phased arrays are also a method of scanning and imaging. The two basic types of scans are the Linear or Electronic scan (E-Scan) and the Sectorial or Azimuthal scan (S-Scan). In the E-Scan, which emulates a manual scan, multiple sound beams are created at the same refracted angle. The beam is electronically translated along the active axis of the array by sequentially adding an element on one end and dropping an element off the other end of the active group of elements within the probe, with time multiplexing coordinated by the instrument’s on-board processor. In the S-Scan, which is unique to phased arrays, the sound beam is electronically swept through a range of user-defined angles by sequentially changing the time delays applied to each element. Because the beam angle is no longer solely dependent upon the wedge angle, more complete data can be obtained and more complex geometries can be examined versus conventional UT. With their distinct features and capabilities, phased arrays require special set-ups and standardization, as addressed by this practice. Commercial software permits the operator to easily make set ups without detailed knowledge of the phasing requirements. 5.3 Phased arrays can be used in different ways: manual or encoded linear scanning; and different displays or combinations of displays. In manual scanning, the dominant display will be an S-scan with associated A-scans. S-scans have the advantage over E-scans in that all the specified examination angles can be covered at the same time. 5.4 The main advantages of using phased arrays for ultrasonic weld examinations are: 5.4.1 Increased control of beam characteristics, including capability for focusing and steering the beam; 5.4.2 Faster scanning and increased probability of detection due to multiple lines/angles acquired and displayed in a single pass; 5.4.3 Increased ability to examine complex geometries and areas with limited access; 5.4.4 Better imaging from the true depth S-scan; 5.4.5 Digital data storage capability, which is intended to enable auditing, archiving, and off-line post-processing, re-processing, and comparison of data from different examinations; 5.4.6 Rapid and reproducible set-ups with electronic instruments.