Background
This case study focuses on addressing downtime challenges with online condition monitoring and achieving savings of €97,000 in an Irish pharma plant specializing in producing Active Pharmaceutical Ingredients (APIs). The plant relies on a range of critical equipment, such as Air Handling Units (AHUs), pumps, compressors, and dryers, to maintain precise manufacturing conditions.
In 2018, the plant began addressing downtime challenges from bearing deterioration in its critical equipment, and the resulting high maintenance costs. To address these challenges proactively and enhance equipment reliability across its operations, the plant opted to implement Eastway’s Safeguard® System. This advanced online condition monitoring system replaced the plant’s conventional manual vibration data collection methods. The strategic adoption of the Eastway’s Safeguard® System enabled continuous monitoring of the plant’s critical equipment, in this case study an AHU, facilitated real-time detection of bearing issues and other potential problems.
The timely maintenance intervention was strategically scheduled during a planned window of opportunity for bearing replacement, demonstrating the effectiveness of continuous monitoring in carrying out maintenance in a planned manner.
Case description
In July 2023, an increase in both velocity (mm/s RMS) and acceleration (g’ RMS) was detected across the Air Handling Unit (AHU) motor test points using the Eastway Safeguard® System. Refer to Figure 1 for the acceleration trend and Figure 2 for the velocity trend of the AHU motor non-drive end from May 2023 to March 2024. These figures illustrate a gradual increase intensifying over time.
Figure 1. Acceleration (g’ RMS) trend from motor non-drive end test point.
Figure 2. Velocity (mm/s RMS) trend from motor non-drive end test point.
Analysis & Recommended Action
After detecting an increase in trends through the Eastway Safeguard® System, an analysis of the vibration data from the motor was conducted by the Eastway remote monitoring team. The API pharmaceutical was notified in August 2023 to plan for the replacement of the motor bearings. The analysis included examining vibration FFT spectra (Fast Fourier Transform) and time waveform signatures. The findings revealed various signs indicative of early bearing deterioration, such as the presence of high peaks in the FFT spectra and non-synchronous frequencies.
Figure 3 illustrates a comparison of acceleration FFT spectra from January 2023 (front blue trend) to March 2024 (rear green trend), highlighting the increasing frequencies associated with bearing deterioration, which intensified over time.
Figure 3. Acceleration (g’ RMS) FFT spectra at the motor non-drive end test point showing frequencies related to bearing increasing over time.
Action taken
Eastway continued to monitor the unit until the scheduled downtime window for AHU motor bearings replacement in March 2024. Following Eastway’s recommendation, site maintenance personnel inspected the unit and found the motor bearings to be worn, with chipped balls and visible damage to the inner race. Consequently, the bearings were replaced. Please refer to Figure 4, which illustrates the acceleration (g’ RMS) trend and shows a significant reduction in vibration levels post-replacement. Additionally, Figure 5 provides a waterfall comparison of the acceleration (g’ RMS) FFT spectra at the motor non-drive end test point before and after maintenance, highlighting the stabilization of frequencies related to the bearing deterioration and confirming the effectiveness of the maintenance intervention.
Figure 4. Acceleration (g’ RMS) trend from motor non-drive end test point after maintenance
Figure 5. Waterfall comparison of the Acceleration (g’ RMS) FFT spectra at the motor non-drive end test point before (rear grey trend) and after (front blue trend) maintenance.
Results
Addressing downtime challenges through the use of online condition monitoring to detect motor bearings deterioration in AHU resulted in reduced downtime and maintenance costs, as well as improved production efficiency by addressing potential issues before they escalated. Close collaboration between the maintenance team and Eastway ensured effective monitoring and timely intervention, leading to successful replacement of AHU motor within a scheduled downtime window.
The table 1 below summarises the importance of having predictive maintenance in place to detect failures, in this case motor bearings deterioration was detected before it progressed to a critical level, allowing corrections to be carried out before costly system failures occurred, thus maintaining operational continuity.
Table 1. Estimated cost savings
