1.1 本规程涵盖了使用X射线或伽马射线对金属和非金属材料进行计算机射线照相（CR）检查的最低要求。 1.2 适用性-- 本规程中的要求旨在控制计算机射线照相检查的质量，而不是旨在建立零件或材料的验收标准。 1.3 应用基础-- 此实践的要求，实践 E2445 和 E2446 应一起使用。实践的要求 E2445 将为CR系统提供基线性能评估和长期稳定性测试程序。实践 E2446 CR性能级别建议在 表1 CR系统的用户应制定一份书面程序，说明其应用中使用的具体要求和测试，并应在检查生产硬件之前获得3级认可射线照相机构的批准。应在书面程序中确定和解决的项目有: 一 人员资格和认证。 b 适用于验收标准并满足射线照相图像质量水平要求的最小有效像素覆盖率 表1 . c 符合规程的附加试验 E2445 视为适当。 d 使用320 kV以上伽马源或辐射能量的组织可能需要修改 E2445 测试、仪表或两者兼而有之。 e 当不是时允许的最大不清晰度 表1 . f 用于为零件和检查设施提供图像可追溯性的方法。 1.3.1 本规程还要求用户进行适合其预期目的的系统鉴定，并发布系统鉴定报告（见小节 7.1 ). 此外，用户应制定特定零件的检查程序（见小节 5.5 和 7.5 ). 1.4 单位-- 以国际单位制或英寸磅单位表示的数值应单独视为标准。 每个系统中规定的值可能不是完全相等的；因此，每个系统应独立使用。将两个系统的值合并可能导致不符合标准。如适用，国际单位制单位显示在括号[xx]中。 1.5 顺从 不符合本规范的系统、设备和材料应获得认知工程组织（CEO）的豁免。 1.6 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者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。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 本规程为CR检查方法的应用和控制确定了基本参数。编写本规程是为了在工程图纸、规范或合同中进行规定。 5.2 焊缝检查-- 有关焊接检查的其他信息，请参阅《实施规程》 E1032 ，ISO 17636-2，或两者兼而有之。 5.3 铸件检验-- 有关铸件检验的其他信息，请参阅《实践》 E1030 . 5.4 电子元件-- 电子部件的射线照相检验应符合规程 E1161 . 5.5 零件特定检查技术-- 以特定零件的检查技术为形式的详细书面程序( 7.5 )应记录每个零件或零件组，并应获得3级认可射线照相机构的批准。 5.6 人员资格-- 根据本规程进行检查的人员应符合ISO 9712、NAS 410、EN 4179、ANSI/ASNT CP 189或SNT的要求- TC-1A，并由雇主或认证机构认证（如适用）。当合同或采购订单上有规定时，可以使用其他等效的资格文件。除非双方之间的合同协议中另有规定，否则适用的修订版应为最新版本。 5.7 系统鉴定-- 所有CR系统应符合其预期用途。第小节规定了系统鉴定要求 7.1 . 5.8 过程控制-- 应监测所有CR系统的长期稳定性（过程控制），如小节所述 7.1.4 . 5.9 预防性维护-- 所有CR系统和X光机都需要定期维护，以确保功能正常。 预防性维护要求见小节 6.2 . 5.10 环境条件-- CR系统应在符合制造商规定的可接受环境条件的环境条件下运行，例如温度和湿度。当CR系统在规定的制造商环境范围外运行时，该系统应合格( 7.1 )对于这样的条件。

1.1 This practice covers the minimum requirements for computed radiographic (CR) examination for metallic and nonmetallic materials using X-ray or gamma radiation. 1.2 Applicability— The requirements in this practice are intended to control the quality of computed radiographic examinations and are not intended to establish acceptance criteria for parts or materials. 1.3 Basis of Application— The requirements of this practice, Practice E2445 , and E2446 shall be used together. The requirements of Practice E2445 will provide the baseline performance evaluation and long term stability test procedures for the CR system. Practice E2446 CR performance levels are recommended in Table 1 . The user of the CR system shall establish a written procedure that addresses the specific requirements and tests to be used in their application and shall be approved by the Cognizant Radiographic Level 3 before examination of production hardware. The items that shall be determined and addressed in the written procedure are: (a) Personnel qualification and certification. (b) Minimum effective pixel coverage appropriate to the acceptance criteria and to meet the radiographic image quality level requirements of Table 1 . (c) Additional tests in accordance with Practice E2445 deemed appropriate. (d) Organizations using a gamma source or radiation energy above 320 kV may need to modify the E2445 tests, gauges, or both. (e) Maximum allowed unsharpness when other than Table 1 . (f) The method used to provide image traceability to the part and the examination facility. 1.3.1 This practice also requires the user to perform a system qualification suitable for its intended purpose and to issue a system qualification report (see subsection 7.1 ). Additionally, the user shall develop part specific inspection procedures (see subsections 5.5 and 7.5 ). 1.4 Units— 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. Where applicable, SI units are shown in brackets [xx]. 1.5 Compliance— Systems, equipment and materials that do not comply with this practice shall require a waiver from the Cognizant Engineering Organization (CEO). 1.6 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. 1.7 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 This practice establishes the basic parameters for the application and control of the CR examination method. This practice is written so it can be specified on the engineering drawing, specification, or contract. 5.2 Weld Examination— Additional information on weld examination may be found in Practice E1032 , ISO 17636-2, or both. 5.3 Casting Examination— Additional information on casting examination may be found in Practice E1030 . 5.4 Electronic Components— Radiographic examination of electronic components shall comply with Practice E1161 . 5.5 Part-Specific Examination Technique— A detailed written procedure in the form of a part-specific examination technique ( 7.5 ) shall be documented for each part, or group of parts, and shall be approved by the Cognizant Radiographic Level 3. 5.6 Personnel Qualification— Personnel performing examinations to this practice shall be qualified in accordance with ISO 9712, NAS 410, EN 4179, ANSI/ASNT CP 189, or SNT-TC-1A and certified by the employer or certifying agency as applicable. Other equivalent qualification documents may be used when specified on the contract or purchase order. The applicable revision shall be the latest unless otherwise specified in the contractual agreement between parties. 5.7 System Qualification— All CR systems shall be qualified for their intended use. System qualification requirements are specified in subsection 7.1 . 5.8 Process Control— All CR systems shall be monitored for long term stability (process control) as specified in subsection 7.1.4 . 5.9 Preventative Maintenance— All CR systems and X-ray machines require periodic maintenance to ensure proper functionality. Preventative maintenance requirements are specified in subsection 6.2 . 5.10 Environmental Conditions— CR systems should be operated within environmental conditions that are in compliance with manufacturer’s stated acceptable environmental conditions, for example, temperature and humidity. When CR systems are operated outside the specified manufacturer’s environmental ranges, the system shall be qualified ( 7.1 ) for such conditions.