Asset Integrity Strategies to Prevent Unscheduled Shutdowns

Maintaining operational continuity is essential in refineries, chemical plants, midstream operations, and similar facilities. Unscheduled shutdowns generate economic losses and operational risks. For example, it is estimated that an average oil and gas facility loses 32 hours of production per month due to unforeseen failures, representing approximately USD 84 million per year [1]. Furthermore, in refineries, critical breakdowns can result in shutdowns that cost up to USD 1.5 million per day [2]. This does not include lost profits, which can undermine the operation's profitability. In addition to reputational damage, it can also result in regulatory fines. Given this scenario, companies have found it beneficial to implement proactive asset-integrity strategies that detect incipient damage before failures occur. The following describes cutting-edge inspection technologies to minimize unscheduled downtime.

Non-Destructive Testing (NDT) is an inspection technique that allows for the anticipation of failures and ensures the integrity of equipment in service. Among the range of NDT techniques, Phased Array Ultrasonic Testing (PAUT), Guided Wave Ultrasonic Testing (GWUT), and Magnetic Flux Leakage (MFL) stand out. PAUT uses multi-element arrays of electronically controlled transducers to scan material with directed ultrasonic beams, revealing corrosion, cracks, and other defects with high precision. GWUT employs low-frequency ultrasonic waves that propagate along pipes to detect discontinuities, proving especially useful in buried, underwater, or insulated pipelines. MFL is a method for detecting metal loss in ferromagnetic equipment, and is regularly used in pipeline lines using instrumented tools or smart pigs.

The latest advancement in enhancing asset integrity strategies involves combining cutting-edge ultrasound methods with data analytics. Utilizing artificial intelligence enables the analysis of large data sets from multiple sources to inform maintenance decisions across industries. Some examples include:

• Ø Continuous asset monitoring for failure prediction supported by the Internet of Things (IoT) [3].
• Ø Inspection data analytics derived from techniques such as PAUT, GWUT, and MFL can be integrated into integrity management systems for predicting asset corrosion and performing RBI risk assessments [4].
• Ø Improving maintenance planning by factoring in equipment criticality, current condition, resource availability, and other considerations to prioritize inspection tasks based on urgency and potential impact on operations [5].

Numerous studies document the use of PAUT, GWUT, and MFL techniques to reduce unscheduled downtime and optimize maintenance. Some examples are presented below.

• Ø Using PAUT on an isolated process tower, a technician discovered anomalous thickness readings during hot-mapping, revealing severe localized corrosion affecting nearly 50% of the thickness. Thanks to early detection, the affected section was replaced, preventing product leakage and process shutdown [2].
• Ø A GWUT inspection of long sections of piping in a refinery led to 99% accuracy in detecting corrosion under clamps and other hidden damage, allowing the company to prioritize repairs during the next scheduled shutdown [6].
• Ø A company implemented a crawler robot equipped with MFL for in-service inspection of an API 650 tank, covering 96% of the tank floor. This allowed for the detection of significant thickness loss, preventing a process shutdown and extending the tank's operation for 15 years under RBI [7].

Below are some of the most significant applications:

• - Determination of wall thickness using the Phased Array scanning method, applying the high-temperature corrosion module (up to 230 °C) to an in-service regenerator at a refinery in Colombia.
• - Evaluation of the integrity and determination of the remaining service life of a digester using a Fitness for Service (FFS) analysis. The digester was affected by cracking associated with the Stress Corrosion Cracking (SCC) mechanism in a caustic environment in the Colombian petrochemical industry.
• - Integrity assessment and remaining life determination of an atmospheric tank affected by cracking due to Stress Corrosion Cracking (SCC) in an ethanol environment, belonging to the Oil & Gas industry in Colombia.
• - Integrity assessment and remaining-life determination of atmospheric tanks affected by accelerated corrosion driven by the combined mechanisms of Stress Corrosion Cracking (SCC) and bacterial corrosion in Oil & Gas industry facilities in Colombia and Peru.
• - Root cause analysis (RCA), integrity assessment, and remaining life determination of the rotating support structure in a 142 GWh solar park located in Guatemala.
• - Finite element analysis (FEA) structural integrity assessment of overhead cranes used in the mining, steel, and power generation sectors in Mexico.

• - Root cause analysis (RCA) to identify damage mechanisms and recurring failures.
• - Finite element analysis (FEA/FEM) for structural simulation and design validation of overhead cranes, tanks, and support structures using Fitness for Service (FFS) methodologies in accordance with API 579.
• - Integrity assessment of equipment in multi-industry sectors (Oil & Gas, petrochemical, mining, steel, renewable energy) using advanced methodologies from API 653, API 510, and API 570.
• - Risk-based assessment of pipelines transporting products in the Oil & Gas industry using API 580 methodologies.

1. Avidor-Peleg, L. Downtime Cost in Process Manufacturing Available online: https://precog.co/blog/downtime-cost-process-manufacturing/ (accessed on 2 October 2025).

2. Blanchet, M.-A. Success Story: Avoiding an Unplanned Downtime Thanks to Ultrasonic Phased-Array Thickness Mapping Available online: https://sonatest.com/blog/success-story-avoiding-unplanned-downtime-thanks-ultrasonic-phased-array-thickness-mapping (accessed on 2 October 2025).

3. Toyo, M. Inteligencia Artificial: Solución Para Mejorarn La Gestión de Activos Available online: https://inspenet.com/articulo/ia-en-la-gestion-de-integridad-de-activos/ (accessed on 2 October 2025).

4. Tai, J.L.; Sultan, M.T.H.; Łukaszewicz, A.; Siemiątkowski, Z.; Skorulski, G.; Shahar, F.S. Preventing Catastrophic Failures: A Review of Applying Acoustic Emission Testing in Multi-Bolted Flanges. Met. 2025, Vol. 15, Page 438 2025, 15, 438, doi:10.3390/MET15040438.

5. Beduschi, F.; Turconi, F.; De Gregorio, B.; Abbruzzese, F.; Tiozzo, A.; Amabili, M.; Prospero, A. Optimizing Rotating Equipment Maintenance Through Machine Learning Algorithm. Soc. Pet. Eng. - Abu Dhabi Int. Pet. Exhib. Conf. ADIP 2021 2021, doi:10.2118/207657-MS.

6. MISTRAS Guided Wave Testing Available online: https://www.mistrasgroup.com/how-we-help/field-inspections/advanced-ndt/automated-ultrasonic-testing/guided-wave-testing/ (accessed on 2 October 2025).

7. DIAKONT Crawler - Type Inspection of Aboveground Petroleum Storage Tank While Filled and In - Operation Available online: https://diakont.com/case-studies/energy-services/crawler-type-inspection-of-aboveground-petroleum-storage-tank-while-filled-and-in-operation/ (accessed on 2 October 2025).