TUD019 High Tech Acoustic Monitoring - Phase 4 (HiTeAM4)

Summary of the project

HiTeAM is a multi-phase joint industry programme that aims to develop a quantitative methodology for condition assessment of highly-loaded low speed bearings in offshore installations. This methodology is based on acquisition and processing of the ultrasonic stress waves generated by changes in the microstructure of a material due to degradation. The mechanism of stress wave generation is also commonly referred to as acoustic emission.

HiTeAM Phase 1 dealt with feasibility evaluation of the approach based on analysis and measurement of inter-component transmission of ultrasonic waves, and on-board measurements for characterization of the background noise in representative offshore environment. HiTeAM Phase 2 dealt with the damage detection and classification methodology and comprised obtaining ultrasonic signatures of various defect types under controlled conditions, formulation of the damage identification approach, sensor system design, laboratory demonstration. HiTeAM Phase 3 dealt with the demonstration of the developed damage identification methodology in representative conditions – both in the lab and in the field – and the development of a condition indicator index for low-speed bearings.

HiTeAM Phase 4 (this project) aims to further develop and validate the methodology and bearing condition index formulation by performing multiple field measurements in collaboration with the project partners. For this purpose, bearings in 6 vessels will be instrumented and investigated.

Goal of the project

The goal of HiTeAM is development and validation of reliable quantitative methods for condition monitoring of highly-loaded low-speed roller bearings. The program focusses on applications of such bearings in the offshore industry, for which notable examples are heavy-lifting cranes, turrets, and turntables, however, applications in other industries include, amongst others, sewage treatment plants, and tunnel boring machines. The overarching objectives of the programme are: (i) early-stage identification and classification of damage, and (ii) maximizing the probability of detection while preventing troublesome false alarms.

HiTeAM Phase 4 aims at validation and demonstration of the developed methodology for assessment of highly-loaded low-speed bearings in representative environment. For this purpose, application of the technology on six (6) candidate cases is aimed for. The cases are envisioned to be a mix of turret bearings, slew bearings, buoy bearings, sheave bearings, and other representative bearings in offshore applications. Each participant is invited to propose a candidate case. The detailed monitoring plan for each case (e.g. sensor layout, data management, safety considerations, measurement duration, etc.) will be co-developed with the case owner. A detailed assessment of the additional engineering and commercial aspects for successful valorization of HiTeAM technology will be performed as well, in close collaboration with the project partners.

Motivation

Heavily-loaded slow-speed bearings in offshore structures are key components in sheave blocks of offshore heavy-lifting cranes, turret mooring systems of FPSO/FSRU/FLNG vessels, yaw mechanism of offshore wind-turbines, and turntables of deep- and shallow-water buoy and offloading systems.

The performance and safety of these high-value assets strongly depend on the integrity of the bearing system. Despite the importance and the need, to date there are no reliable non-intrusive inspection or monitoring methods for assessment of the condition of the slow-speed bearing systems.

HiTeAM aims to develop quantitative monitoring methods that can assess the integrity of heavily-loaded slow-speed bearings and contribute to the improvement of safety, longevity, and efficiency of high-value offshore and maritime assets.

Innovativeness

In the literature, prior work has been performed on the development of condition monitoring methods for bearings. However, the main focus of the bulk of this work has been medium- to high-speed bearings. In some studies, low-speed applications are investigated based on which acoustic emission (AE) is considered to have the highest potential in terms of sensitivity to damage. However, the efforts were hampered by the difficulty of processing large samples of complex data that are associated with such ultrasonic monitoring. Recent advancements in data acquisition and management technology have opened up new possibilities for HiTeAM4 7/10 more extensive data collection and analysis. These allow for the recording of the large amounts of damage-induced waveforms that are required for the quantitative processing methodologies in HiTeAM. These developments are unique from the scientific point of view since they incorporate multiple disciplines of ultrasound, damage mechanics, structural

dynamics, instrumentation, and signal processing. The researchers have not encountered any comparable holistic approach in the literature for this challenge.

Valorisation

Duration of the project

Start date: 01/02/2023

End date: 31/01/2025