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Chemical fertilizer granules

Bearing damage in ball mill gearbox

This case study from the Agropolychim AD chemical plant in Bulgaria showcases the effectiveness of the HD ENV vibration monitoring technology, which detected bearing damage in a gearbox in a production-critical ball mill.

The Agropolychim vibration diagnostic team employs Leonova Diamond portable analyzers for routine vibration data collection on critical machinery. The case study covers data between August 2018 and September 2020, with bearing fault frequencies aligning with BPFI and BPFIM symptoms emerging in March 2020. Four months later, these frequencies also appeared in the EVAM vibration assignment spectrum, hinting at possible stage 4 bearing damage. The decision to halt machinery for repairs depends on factors such as production dependencies and costs. To minimize financial losses, the plant opted for an unplanned stoppage on September 3rd, 2020, to replace the damaged gearbox.

The case highlights the HD ENV technology's capacity to accurately detect bearing damage. As a consequence of this case, the company upgraded its analyzers and software with the complete HD technology package. They also equipped the gearbox with shock pulse adapters for data collection with DuoTech accelerometers and quick connectors for optimal signal quality.

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Case Study
Filename/description Language Size Modified
CS_038B_Ball mill_Agropolychim_BG.pdf English (United Kingdom) 9 MB 8/22/2023
Case study from the Agropolychim AD chemical plant in Bulgaria involving bearing damage in a ball mill gearbox.

HD Technologies

High-definition condition monitoring technologies provide exceptional pre-warning times, maximizing the planning horizon for maintenance and repairs. In turn, this enables fully utilizing asset life, cutting repair costs, and minimizing the consequences of unplanned downtime.

Leonova Diamond

Leonova Diamond® is an advanced and powerful data analyzer for high-efficiency measuring routes in rough industrial surroundings.


Chemical industries are generally sensitive to production stoppages. Due to long production chains in the lines, breakdowns have a significant negative impact.