A 700 tonne per hour ore beneficiation plant saves $70,000 per annum in greasing costs due to incorrectly set up automatic lubricators.
By Jason Crouch
A review of the hydrocarbon management practices at a beneficiation plant identified that over 95% of the bearings within the plant were being over–greased (some bearings receiving three times the required grease). This meant, due to the high grease usage, not only was the supplier having difficulty keeping up supply, the client was also utilising valuable resources changing out the empty canisters.
Whist assisting a client develop new maintenance strategies for a section of their washing and screening process, we identified issues with their automatic lubrication approach. The client had recently installed this section of plant as a way of reducing rehandling costs, and since the commissioning had chosen to stop manual greasing and install automated grease dispensers instead.
Whilst developing the maintenance strategies and investigating reliability issues with the equipment vendors, we identified that the client was experiencing high bearing failure rates due to excessive greasing. We therefore reviewed the existing lubrication settings, covering all the grease points within the washing and screening section.
The investigation led us to ask why the site had set the automated grease dispensers to such a high setting. We found that, due to a misinterpretation of the plant manufacturer’s service manual, the client had set the automated grease dispensers to dispense the recommended amount of grease into each available port on the housing, instead of in total.
For example, rather than delivering 4g/day total to the bearing housing, 4g/day was being delivered to each labyrinth port, plus an additional 4g/day into the bearing port resulting in a total of 12g/day into the bearing housing.
By making this change, the site saved $70,000 per annum through reducing the number of greasing units purchased. In addition, further savings were made by reducing the frequency of the lubrication rounds from weekly to monthly.
With the mining and manufacturing financial environment being as cyclic as it is, there are many examples of plants that have been through the process of manual greasing, to automated grease dispensers, back to manual greasing and so on. This situation is a prime example of how automated lubrication can be utilised correctly improving equipment life and freeing up vital resources to attend to other matters.
Bluefield has learned that a regular review of hydrocarbon management and condition monitoring practices is essential to minimising costs and reducing the risk of asset failure. (We’ve previously written about it here). Further, we recommend consulting with the bearing manufacturers to ensure the correct greasing volumes are in use and that the people responsible for maintaining the system are aware of the requirements and consistently apply the correct grease volumes.