1.1 在优选实施例中，本实践检查浸入式低碳锻造管道浸入水箱中，声学传感器永久安装在水箱壁上，而不是暂时安装在零件本身上。在通过高达1000巴的静水压方式对管道进行内部加载（应力）时，对管道进行监测。 1.2 本规程检查沉管或非沉管，当存在裂纹时，沉管或非沉管通过内部静水压方式承受应力，以产生声发射。然而，非浸入式方法很耗时，需要为每个被检查的管道放置和拆除传感器，而浸入式方法永久安装了传感器，为储罐提供了一致的传感器耦合，无需重新安装。出于特定原因，不建议使用非浸入式方法，本标准其余部分将仅讨论浸入式方法。这类似于实践中描述的压力容器测试 E569 ，但使用该标准中未包含的静水压方法。 1.3 该声发射（AE）方法用于监测低碳锻造管道系统，该管道系统在浸入水浴中时，通过高达1000 bar[15000 psi]的静水压方式进行内部加载（应力），以促进传感器耦合。 1.4 声发射监测系统的基本功能是检测、定位和分类发射源。其他无损检测（NDT）方法可用于进一步评估声发射源的重要性。 1.5 这种做法可以用来取代视觉方法，因为视觉方法不可靠，具有重大安全风险。 1.6 本规程描述了安装和监测由受控静水压力刺激的局部异常引起的声发射的程序。 1.7 其他无损检测（NDT）方法可用于进一步评估声发射源的重要性。 1.8 以国际单位制或英寸表示的数值- 磅单位应单独视为标准单位。每个系统中规定的值可能不是精确的等效值；因此，每个系统应相互独立使用。将两个系统的值合并可能会导致不符合标准。 1.9 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和健康实践，并确定监管限制的适用性。 ====意义和用途====== 5.1 在所有油田应用中泵送的高压流体通常对铁管造成压力，随后的故障可能导致人员或设备受伤。这些锻件通常由4700系列低碳钢制成，壁厚超过1.25厘米[0.5英寸]，取决于制造商的规格。证明这些铁段能够承受操作压力的标准方法是进行着色渗透（PT）或磁粉渗透（MT）测试，或两者都进行，以发现缺陷（裂纹和腐蚀）。 由于这些方法需要通过人眼进行解释，因此需要采用一种技术，即基于传感器的系统可以提供信号来通过或不通过测试对象。为此，声发射（AE）方法提供了必要的数据，计算机可以根据这些数据进行验收/拒收，将人从回路中拉出，前提是人已正确编程验收标准。这些管段大多不是线性的，因此需要一种三维缺陷定位方法。3D声源指示表示缺陷的空间位置，而不考虑其方向，因为声音通过零件和水浴传播，因此声源位置仅为近似位置。 5.2 由于需要检查的零件数量较多，浸没式3D方法更为可取。3D系统易于复制和标准化，因为所有传感器位置都固定在液浴的外部。 多个零件可以很容易地放置在一个组件中，允许在一次测试中对所有零件进行检查，从而加快了吞吐量。在油箱上安装至少八个声发射传感器可以提高事件中发生足够数量声发射命中的概率，从而可以大致确定位置。当观察到缺陷迹象时，通过空间位置识别受试零件，允许将其移除以进行进一步检查，或拒绝使用。浸没测试配置如所示 图1 a和b。

1.1 In the preferred embodiment, this practice examines immersed low carbon, forged piping being immersed in a water tank with the acoustic sensors permanently mounted on the tank walls rather than temporarily on the part itself. The pipes are monitored while being internally loaded (stressed) by hydrostatic means up to 1000 bar. 1.2 This practice examines either an immersed pipe, or non-immersed pipe being stressed by internal hydrostatic means to create acoustic emissions when cracks are present. However, the non-immersed method is time consuming, requiring placement and removal of sensors for each pipe inspected, while the immersed method has sensors permanently mounted, providing consistent sensor coupling to the tank-eliminating reinstallation. The non-immersed method is not recommended for the specified reasons and only the immersed method will be discussed throughout the remainder of the standard. This is similar to pressure vessel testing described in Practice E569 , but uses hydrostatic means not included in that standard. 1.3 This Acoustic Emission (AE) method addresses examination for monitoring low carbon, forged piping systems being internally loaded (stressed) by hydrostatic means up to 1000 bar [15,000 psi] while being immersed in a water bath to facilitate sensor coupling. 1.4 The basic functions of an AE monitoring system are to detect, locate, and classify emission sources. Other methods of nondestructive testing (NDT) may be used to further evaluate the significance of acoustic emission sources. 1.5 This practice can be used to replace visual methods, which are unreliable and have significant safety risks. 1.6 This practice describes procedures to install and monitor acoustic emission resulting from local anomalies stimulated by controlled hydrostatic pressure. 1.7 Other methods of nondestructive testing (NDT) may be used to further evaluate the significance of acoustic emission sources. 1.8 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.9 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 and health practices and determine the applicability of regulatory limitations prior to use. ====== Significance And Use ====== 5.1 High pressure fluids being pumped in all oil field applications often stress iron pipes where subsequent failure can lead to injury to personnel or equipment. These forgings are typically constructed from 4700 series low carbon steel with a wall thickness in excess of 1.25 cm [0.5 in.], dependent on the manufacturers' specification. The standard method to certify that these iron segments can withstand operational pressures is to perform dye penetrant (PT) or magnetic particle penetrant (MT) tests, or both, to reveal defects (cracks and corrosion). As these methods are subject to interpretation by the human eye, it is desirable to employ a technique whereby a sensor based system can provide a signal to either pass or fail the test object. To that end, the acoustic emission (AE) method provides the requisite data from which acceptance/rejection can be made by a computer, taking the human out of the loop, providing that a human has correctly programmed the acceptance criteria. Most of these pipe segments are not linear, thus a 3D defect location method is desirable. The 3D source indication represents the spatial location of the defect without regard to its orientation, recognizing the source location is only approximate due to sound propagation through the part and water bath. 5.2 The immersed 3D approach is found to be preferable due to the large number of parts to be examined. The 3D system is easily replicated and standardized in that all sensor locations are fixed to the exterior of the fluid bath. Multiple parts may be easily placed into an assembly, allowing all to be examined in a single test, thus accelerating throughput. Attaching a minimum of eight AE sensors to the tank enhances the probability that a sufficient number of AE hits in an event will occur, allowing for an approximate location determination. When an indication of a defect is observed, the subject part is identified by the spatial location allowing it to be removed for further examination, or rejected for service. An immersed test configuration is shown in Fig. 1 a and b.