API Standard 1163, In-Line Inspection Systems Qualifications, is an industry standard that describes how to qualify an In-Line Inspection (ILI) system’s performance as well as guidance for verifying and validating the results of an In-Line Inspection. Originally issued in 2005, API 1163 was a way for pipeline operators and service providers to standardize the performance of In-Line Inspections. A second edition was issued in 2013 and reaffirmed in 2018, and a third edition in 2021. Each new edition includes added and clarified requirements along with guidance for successfully conducting an ILI. API 1163 is an umbrella document covering all aspects of ILI systems incorporating the requirements of NACE Standard Practice 0102 - In-Line Inspection of Pipelines and ASNT Standard - In-Line Inspection Personnel Qualification and Certification by reference. Together, these three documents provide service providers and pipeline operators the foundation for consistently qualifying the equipment, people, processes, and software utilized in the ILI industry.

ANSI-ASNT ILI-PQ was developed by the American Society for Nondestructive Testing ASNT and approved by the American National Standards Institute (ANSI). ASNT ILI-PQ establishes minimum requirements for qualification and certification of In-Line Inspection personnel. A Personnel Qualification Statement describes the qualifications and safety relevant trainings for all qualified personnel who perform Field Service, Tool Maintenance or Data Evaluation for the In-Line Inspection. The standard includes qualification and certification for Levels I, II and III.

The process of ILI tool selection, as detailed in section 5 of API SP 1163, is the responsibility of the operator. The operator must determine whether an inspection system has the potential to meet the detection and sizing objectives needed to ensure the integrity of the pipeline for specific pipeline threats. In addition, the operational physical and operational constraints including diameter, wall thickness, internal pressure, flow velocity, and cleanliness to name a few must also be considered. This presentation reviews the general capabilities and limitations of in-line inspection technologies for their potential to assess specific integrity concerns caused by pipeline anomalies, and the influence of key operational factors on inspection results.

Pipeline operators are required to verify and validate the results of their inspections. Section 7 of 1163 defines the requirements for verifying that an ILI system is prepared and run in the manner defined as necessary to achieve the Performance Specifications as outline in Section 6 – Qualification of Performance Specifications. Verification confirms an inspection achieves its desired purpose according to plans and procedures and provides inspection results with the expectation to meet the ILI Performance Specification. The intent of System Operational Verification is to ensure the ILI service meets contractual obligations and performs as intended.

This presentation will walk through steps needed to achieve validation of an in-line inspection run. At the surface, the process appears to be straightforward, but validation is anything but that. We will talk about the uncertainty in the process, including measurement and sampling considerations; starting with the level 1 (lowest level, highest uncertainty) and conclude with a level three. Additionally, an approach for comparing ILI results to field measurements will be presented that includes the associated ILI error and NDT error. An overview of the statistics behind selection of digs and calculation of ILI tool acceptance will wrap up this presentation.