ASME’s role in the standardization of NDT

Introduction

Non-Destructive Testing (NDT) plays an important role in helping companies ensure the integrity and safety of materials and structures during the different phases of construction and subsequent commissioning. ASME Section V is a reference code that addresses NDT requirements such as personnel qualifications, procedures, equipment, calibrations, and demonstration of NDT procedures.

This article addresses the importance of ASME on NDT Standardization, mentioning the topics and tests covered, discusses inspection reliability, and highlights the importance of the ASME code in the context of NDT.

Importance of ASME in non-destructive testing standardization

ASME Section V is a vital part of the ASME Boiler and Pressure Vessel Code (BPVC), dedicated to non-destructive examination (NDE) of materials. It provides detailed guidelines and standards for various NDE methods, ensuring that inspections are performed consistently and accurately across different industries.

The importance of ASME in non-destructive testing standardization through Section V cannot be underestimated. By providing standardized guidelines and requirements, it ensures that NDT methods are applied consistently across different industries and geographic locations. This consistency improves the reliability of inspections, reduces the risk of undetected defects, and ultimately contributes to the safety and integrity of critical infrastructure.

Historical context

Since 1911, the American Society of Mechanical Engineers (ASME) established the Boiler and Pressure Vessel Committee to formulate standard rules for the construction of steam boilers and other pressure vessels. Non-destructive testing (NDT) has been considered an important part of manufacturing process assurance. ASME Section V has evolved over the years to incorporate the latest advances in NDT technologies.

Initially, NDT methods were rudimentary, relying heavily on visual inspections and basic examination techniques. However, as technology advanced, the need for more sophisticated and reliable testing methods and techniques became apparent. As a result, ASME Section V responded to this need and has been continually updating its standards to include increasingly advanced techniques and procedures.

The ASME Code

The ASME Code, including ASME Section V, is a comprehensive set of standards and guidelines for the design, manufacture, inspection, and testing of pressure vessels, boilers, and other critical components. It is widely recognized and adopted by industries around the world, serving as a benchmark for quality and safety. The ASME in the standardization of non-destructive testing has had a great impact on the application and obtaining reliable results, making it an indispensable tool in the integrity of the various components of the process units.

Scope and impact

• Comprehensive coverage: The ASME Code covers a wide range of topics, including materials, design, construction, inspection, and testing. It provides detailed requirements for various industries, ensuring that all aspects of component integrity and safety are addressed.
• Global recognition: The ASME Code is internationally recognized and adopted by industries around the world. Its standards are referenced in regulations, contracts and quality assurance programs, ensuring a high level of consistency and reliability in NDT practices.
• Continuous Improvement: The ASME Code is continually updated to incorporate the latest advances in technology and industry practices. This commitment to continuous improvement ensures that the code remains relevant and effective in addressing emerging challenges and maintaining high standards of quality and safety.

Section V of ASME on NDT standardization

The ASME in the standardization of Non-Destructive Testing is found in section V, and it consists of two subsections or fundamental parts, as follows.

Subsection A

This can be subdivided into two parts.

• General requirements: Article 1 of ASME Section V describes the general requirements for NDT procedures, including personnel qualification, equipment calibration, and documentation. These requirements ensure that all NDT activities are performed by qualified individuals using properly calibrated equipment, thus maintaining high standards of accuracy and reliability.
• NDT application requirements: From article 2 to article 21, Section V provides detailed rules for various NDT, such as: Industrial Radiography (RT), Ultrasonic (UT), Magnetic Particles (MT), Penetrant Liquids (PT), Eddy Currents (ECT), Leakage Testing (LT), Acoustic Emission (AET)for the examination of metal components under pressure, Acoustic Emission (AET) for continuous monitoring of pressurized components, Ultrasonic Testing (UT), Alternating Current Field Measurement (ACFMT), Magnetic Field Leakage (MFL), Remote Field (RFT), Acoustic Pulse Reflectometry (APR), Guided Waves (GWT), Computed Tomography, and Pulsed Eddy Currents (PEC) test performance demonstration criteria. Each method-specific standard includes guidelines on the application, interpretation, evaluation, and reporting of test results.

Subsection B

• Adopted standards: From article 22 to 31, ASME Section V presents standards adopted from ASTM for several tests (one test for each article) to which an “S” is added to the identification of the original (for example, ¨ASTM E797¨ in ASME Section V is rewritten as ¨Article 23 SE797¨). Some of these standards (very few), present certain modifications with respect to the original document, and generally with the purpose of emphasizing or strengthening some specific point of the document, and thus made known on the cover of the document.

It should be noted that article 3 of this section is empty, i.e., article 4 follows directly after article 2, because article 3, which dealt with radiography in foundries, was eliminated some time ago, and the guidelines for this application were included in article 2.

Another observation regarding section V of the ASME code is that this ¨No¨ defines the acceptance criteria for different types of defects and imperfections, since these are contemplated in the construction codes such as ASME B31.3, ASME 31.8, ASME Section VIII Divisions 1 and 2, among others. Section V only details the application requirements of the different tests and this document is referenced both by the construction codes within the ASME compendium, as well as by other documents outside of it¹, such as the API 650 standard.

Reliability of inspections through standardization

Inspection reliability is a key aspect of nondestructive testing, directly impacting the safety and performance of critical infrastructure. Reliable inspections ensure that defects and failures are accurately detected, evaluated and addressed, preventing potential failures and accidents.

ASME’s standardization of Non-Destructive Testing plays a crucial role in improving the reliability of inspections. By following standardized guidelines and procedures, industries can minimize variability and errors in NDT application processes and results. ASME Section V ensures that all aspects of NDT, from personnel qualifications to equipment calibration and adherence to procedures, are standardized, leading to more reliable and consistent inspections.

Specific requirements such as radiographic interpretation are covered in Section V (see figure 1).

Factors affecting the reliability of inspections

• Personnel qualifications: The competence and experience of NDT personnel are crucial for reliable inspections. ASME Section V describes the qualification and certification requirements for NDT technicians, ensuring that they have the skills and knowledge necessary to perform accurate inspections.
• Equipment calibration: Proper calibration of NDT equipment is essential for accurate and consistent results. ASME Section V provides guidelines for calibration and maintenance of equipment, ensuring that it operates within specified tolerances.
• Procedural adherence: Strict adherence to standardized procedures is vital to inspection reliability. ASME Section V includes detailed procedures for various NDT methods, ensuring that inspections are performed in a consistent and repeatable manner.
• Environmental factors: Environmental conditions, such as temperature, humidity and lighting, can affect the accuracy of NDT results. ASME Section V provides recommendations for controlling environmental factors during inspections, minimizing their impact on reliability.

Conclusions

ASME’s role in standardizing nondestructive testing is indispensable in ensuring the safety, reliability, and integrity of critical infrastructure. The ASME Code in standardizing nondestructive testing through Section V, with its comprehensive guidelines and standards, plays a vital role in improving reliability in the application of NDT methods and techniques and their results. By adhering to the ASME Code, industries can achieve consistent and accurate inspections, minimizing the risk of undetected defects and contributing to the overall safety and performance of critical components and structures.

The importance of ASME Section V, and the rest of the ASME code documents in the context of NDT, cannot be underestimated, as they collectively ensure that nondestructive testing remains a powerful tool of modern industrial practices.

References

1. ASME V. Nondestructive Examination; Accessed September 29, 2023.