Allnorth completed a project for Mosaic’s potash solution mine in Belle Plaine, SK to redesign the slurry pump shaft for settling pond dredges #3 and #4. The previous shaft design had suffered from frequent failures: in a period of 1.5 years, and on three occasions, the threaded end of the shaft for connection to the impeller sheared off. The pump is subject to frequent ingestion of large solids, including 3” diameter rocks.
In short order (2 weeks), Allnorth assessed the existing design, determined the root cause of the failure, generated a list of potential design changes to reduce failures, reviewed the options with the client, performed FEA on preferred design changes, identified the highest-value design changes, reviewed results with the client, and revised a drawing for the shaft.
Maximum stress in the new shaft design is expected to be 50% of the previous design, which will ensure stress is kept below the endurance limit. It is expected that this particular failure mode will not occur in the future.
- 3D modeling
- Generate multiple design improvement concepts
- Stress analysis (FEA) of existing design and concepts
- Report on recommendations for modifications
- Modification and mark-up of drawings
Belle Plaine, SK