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Before the retrofit, the pump used a traditional stuffing box packing arrangement. In this abrasive service, the shaft sleeve wore quickly, requiring replacement around every four months. While the impeller and rubber liners were typically replaced annually, sleeve change-outs were major maintenance events, taking around 36 hours, requiring a full mechanical crew across two shifts, and involving a 100-ton crane.
A mechanical seal package was designed to replace the original packing arrangement and retrofit onto the existing pump setup without modifications. The seal uses a controlled clean flush to maintain a cleaner environment at the sealing interface, with materials selected for abrasion tolerance in demanding slurry service.
After commissioning, the site saw a significant reduction in clean sealing-water demand. Under the operating conditions at the time, the change equated to around 288,000 liters per day less clean water used for sealing. For operations where water availability, treatment effort or cost are rising constraints, this shows how targeted upgrades can support sustainability and operational resilience.
The retrofit was also designed to align maintenance with the site’ s planned annual major service interval, when the impeller and liners are replaced, reducing the need for additional intrusive interventions across the year.
The optimum sealing arrangement depends on factors including slurry concentration, pressure, shaft speed, water availability, and maintenance strategy
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