{"id":2715,"date":"2024-08-29T09:30:28","date_gmt":"2024-08-29T15:30:28","guid":{"rendered":"https:\/\/www.vibrantndt.com\/?p=2715"},"modified":"2024-08-29T09:30:28","modified_gmt":"2024-08-29T15:30:28","slug":"enhancing-aircraft-safety-with-part-to-itself-pti-inspection-a-new-standard-in-wheel-integrity","status":"publish","type":"post","link":"https:\/\/www.vibrantndt.com\/de\/enhancing-aircraft-safety-with-part-to-itself-pti-inspection-a-new-standard-in-wheel-integrity\/","title":{"rendered":"Enhancing Aircraft Safety with Part-to-Itself (PTI) Inspection: A New Standard in Wheel Integrity\u00a0"},"content":{"rendered":"

In the aerospace industry, ensuring the integrity of aircraft components, especially wheels that endure extreme operating conditions, is crucial. Traditional inspection methods, often relying on sampling, fall short in detecting early-stage damage. To address this, Part-to-Itself (PTI) has emerged as a groundbreaking solution, offering unparalleled sensitivity and precision.<\/span>\u00a0<\/span><\/p>\n

Understanding PTI: A New Approach in Maintenance Repair & Overhaul (MRO)<\/span><\/b>\u00a0<\/span><\/h3>\n

PTI is a precision inspection method that tracks the resonance profile of individual components over time. By comparing subsequent measurements to the initial baseline, we can identify even subtle changes indicative of potential damage, such as cracks, before they escalate into critical failures. The underlying technology is supported by our patented methods (EU: 2630437, US: 10481104, 10718723 and others), ensuring the highest level of accuracy and reliability in inspection.<\/span>\u00a0<\/span><\/p>\n

The general PTI approach in MRO involves measuring the part during one visit, then re-measuring it during subsequent visits to verify that it hasn’t changed „too much“ compared to other parts. This method has proven to be the most sensitive mode of Process Compensated Resonance Testing (PCRT), as it can see through part-to-part variation and detect when a specific serial number part starts to change, accumulate damage, propagate a crack, build or release residual stress, erode, or change dimension.<\/span>\u00a0<\/span><\/p>\n

How PTI Works<\/span><\/b>\u00a0<\/span><\/h3>\n

The PTI process involves several key steps:<\/span><\/p>\n

<\/span>Step 1) Establishing a Baseline<\/span> (Birth Certificate)<\/span> Resonance Profile<\/span><\/span>: <\/span><\/span><\/strong>F<\/span><\/span>or each wheel, we <\/span><\/span>establish<\/span> an <\/span>initial<\/span> baseline resonance profile.<\/span> This can be when it first comes from the manufacturer or at the \u201cfirst MRO point\u201d<\/span><\/span><\/p>\n

\"\"Figure 1 Illustration of how the resonance spectra may change from the birth certificate baseline as the part goes into service and receives various repair or overhaul operations. In this example, the resonance peaks shift higher as a result of the service interval, and are restored by the repair to \u2018near new state\u2019. Quantification, comparison and analysis of these changes over the service life of a part offers new opportunities to life management. <\/em><\/p>\n

Step 2) Regular Comparisons<\/span><\/span><\/strong>: <\/span><\/strong>Subsequent<\/span> measurements are regularly compared to this baseline.<\/span><\/span>\u00a0<\/span><\/p>\n

Step 3) Identifying<\/span> Shifts<\/span><\/span><\/strong>:<\/strong> Significant resonance shifts are <\/span>identified<\/span> for further investigation.<\/span><\/span>\u00a0<\/span><\/p>\n

\"\"Figure <\/span><\/span>2<\/span><\/span><\/span> In this graph, each set of colored dots <\/span>represents<\/span> a different set<\/span> of turbine blades, with PTI data comparing the parts before and after a service interval<\/span>.<\/span>\u00a0 <\/span>This type of PCRT PTI analysis allows detection of individual parts that might be changing more than others (blue or grey dots outside of the expected limits)<\/span>.\u00a0 <\/span>It also allows detection of whole sets of parts (green dots) that might be aging or performing differently than other sets.<\/span><\/span>\u00a0<\/span><\/em><\/p>\n

Step 4) Integration with Other Methods<\/span><\/span><\/strong>:<\/strong> PTI findings are corroborated by other inspection methods such as Eddy Current, Penetrant, and Visual Inspection. However, PCRT and PTI are fully automated, removing the potential for human <\/span>error<\/span> and allowing valuable NDT resources to focus on the highest risk components<\/span>.<\/span><\/span>\u00a0<\/span><\/p>\n

Real-World Impact: Case Study on Wheels<\/span><\/b>\u00a0<\/span><\/h3>\n

Our extensive experience with PTI, involving measurements of over 60,000 wheels, has yielded remarkable results. In this population, we have over 1,000 PTI pairs (pairs of measurements of the same wheel). We have seen many cases where the wheel shows no significant change, indicating it remains in good condition. However, we have also identified instances where significant resonance changes were detected. These findings were often supported by the detection of cracks through other methods, proving the efficacy of PTI.<\/span>\u00a0<\/span><\/p>\n

\u00a0<\/span>\"\"Figure 3 Wheel spoke crack detected by PCRT PTI inspection.<\/i><\/p>\n

For example, we detected spoke cracks in two outboard wheels. These parts were measured with PCRT by the MRO site before and after a service interval. (Note that the measurements did not need to be taken at the same MRO location. This highlights the flexibility of PTI, as comparisons can be made regardless of inspection site.) Similar detectable PTI changes were observed in the same peaks for both wheels after cracking, validating the sensitivity and reliability of this method<\/span>\u00a0<\/span><\/p>\n

\u00a0<\/span><\/p>\n

\"\"<\/span>Figure <\/span><\/i>4<\/span><\/i> – 3 wheels (B, C, D) were each measured twice with at least 9 months between measurements.\u00a0 Wheel B\u2019s resonance data shows very little change over this interval.\u00a0 However, wheels C and D, both of which were confirmed to have spoke cracks by further NDT, show significant change, due to the initiation\/propagation of the damage.\u00a0 The peak labeled 10 shifts lower in frequency as a result of the crack, and the spacing\/pattern of peaks at peaks 11-12 changes noticeably as well.<\/span><\/i>\u00a0<\/span><\/p>\n

\u202f<\/span>Beyond Wheels: Expanding PTI Applications<\/span><\/b>
\nWhile PTI has proven invaluable in wheel inspection, its potential extends far beyond. By meticulously tracking individual component histories, PTI can revolutionize the maintenance and inspection of various aircraft parts. Adhering to ASTM E3213 standards, this method excels in identifying subtle changes that may signal impending issues.<\/span>\u00a0<\/span><\/p>\n

Specifically, PTI can be applied to other critical components such as landing gear components, blades, disks, and even serialized fasteners. By comparing each part to its own historical data, rather than population averages, PTI offers unparalleled sensitivity in detecting anomalies.<\/span>\u00a0<\/span><\/p>\n

A particularly promising application lies in the realm of life-limited parts. Traditionally, these components are replaced based on predictive models, often leading to the premature disposal of perfectly serviceable parts. PTI has the potential to change this paradigm by providing real-time data on a part’s condition. Through continuous monitoring, we can identify parts that are degrading prematurely while also extending the life of those performing as expected. This not only enhances safety but also delivers significant cost savings.<\/span>\u00a0<\/span><\/p>\n

By expanding the use of PTI, we can usher in a new era of predictive maintenance, optimizing aircraft performance and reducing downtime.<\/span>\u00a0<\/span><\/p>\n

\u00a0<\/span>The Future of Inspection: Continuous Improvement<\/span><\/b>\u00a0<\/span><\/h3>\n

We are currently testing a PTI sort on a specific wheel part number in a process termed a „CHAIN.“ Quickly testing with various types of sorts provides multiple layers of risk mitigation:<\/span>\u00a0<\/span><\/p>\n