A recent poll by Xylem of mining operators found that for 33% of respondents, “system uptime” was the greatest underlying constraint on-site. Reliable systems that keep running to consistently support production are key to success. So, how does a plant operator ensure reliability? A key factor is regular, scheduled maintenance, particularly for hard-working slurry pumps, according to Jessy Parmar, business development manager for Xylem.
Other aspects to bear in mind include selecting the right pump for the task at hand and ensuring it runs as close as possible to its “best efficiency point” (BEP), Parmar explained. “Running a pump at BEP supports optimal performance while minimizing wear and tear,” Parmar said. “There are also some helpful digital or ‘smart’ technologies that support equipment to run optimally. Variable frequency drives, for example, enable a pump to vary performance in real time based on the fluctuating need. Remote monitoring and control technologies can provide insight into pump performance without the need to be on-site; a tangible convenience saving resources and time that can be invested in other tasks. Some pumps feature built-in thermal contacts and leakage sensors that automatically signal an alarm or stop the pump from running, if necessary.”
All that said, Parmar stresses regular maintenance. “Generally, three inspections are recommended — initial, periodic and an overhaul,” Parmar said. “It is advisable to check the installation, operation and maintenance manual for the recommended service.” For example, the following approach is recommended:
Initial inspection – Within the first year of the pump’s operation, an initial inspection checks the pump’s condition. It is also important to check wiring. If the pump is not wired correctly, it runs in reverse, which results in the impeller potentially stripping or a loss in performance. The results of this inspection will determine the ideal intervals for periodical inspection and when a more in-depth overhaul for the installation will be required.
Periodic inspection – Up to 4,000 hours or one year, whichever comes first. Applies to normal applications and operating conditions at media (liquid) temperatures <40°C (104°F). This inspection prevents operational interruptions and machine breakdowns. Any measures required to increase performance and pump efficiency are decided during this inspection. For example, impeller trimming, wear part control and replacement, control of zinc-anodes and control of the stator.
Overhaul – Up to 8,000 hours or three years, whichever comes first. Applies to normal applications and operating conditions at media (liquid) temperatures <40°C (104°F). An overhaul lengthens the operating lifetime of the product. It includes the replacement of key components as well as measures carried out during a periodic inspection.
Shorter intervals between inspections will be required when the operating conditions are extreme, for example in very abrasive or corrosive applications or when the liquid temperatures exceed 40°C (104°F).