Vibration Monitoring in Dry-Installed Pump Stations

Sammanfattning

This thesis investigates how vibration monitoring can be introduced as part of preventive maintenance for dry-installed centrifugal pumps operated by Sörmland Vatten. The study addresses a practical problem: although these pumps are critical for the distribution of drinking water and the transport of wastewater, there is currently no structured system for vibration-based condition monitoring. Since common pump faults such as bearing damage, imbalance, misalignment, looseness and cavitation often develop gradually, vibration monitoring offers the possibility of detecting degradation before a functional failure occurs. The work was carried out as a technical decision-support study rather than as a full implementation project. The method combined literature review, site visits, dialogue with Sörmland Vatten, analysis of internal pump data, review of relevant standards, product comparison and invoice-based cost analysis. ISO 20816 was used as the main reference framework for measurement principles, vibration zones and alarm logic. A technologyneutral requirement specification was developed and used to evaluate three industrially relevant system alternatives: ifm VVB3, Turck CMVT and Kübler CMSVT38. In parallel, an integration analysis was performed to assess how vibration data could be transferred through PLC/RTU to VA-operatör and used as maintenance support in MaintMaster. The results show that a suitable future solution should be based on three-axis vibration measurement, overall vibration velocity in mm/s RMS, trend logging, two-stage alarm handling and local baseline verification. The study further shows that the key implementation challenge is not the sensor itself, but the surrounding integration, alarm structure and organizational use of measured data. The economic analysis, based on verified invoice data from 2018–2022, indicates that the observed repair pattern corresponds to a mean time between repairs of 8.5 years for the analysed pump group. When combined with a conservative investment estimate, the modeled payback period for vibration monitoring is about 1.7 years. Overall, the thesis concludes that vibration monitoring is technically feasible and strategically relevant for Sörmland Vatten, provided that the implementation is standardized, pilot-tested and supported by baseline measurements in real operation. The study therefore recommends a staged implementation approach, starting with a pilot installation on selected high-priority pumps before wider rollout.