Wear control and filtration company Filter Focus points out that, through oil filtration and lubrication, mines will achieve cost-saving results in maintenance.

“Mines are seeking ways of reducing costs, and maintenance is seen as a costly department in some mines. Filter Focus offers a solution that will change the negative perception of maintenance work at plants into a positive one, where maintenance is a cost-effective part of mine [manage- ment]. This can be done through proper lubrication and the effective oil filtration of equipment,” says Filter Focus COO Craig FitzGerald.

He mentions that two years ago, chrome deposit miner Hernic Ferrochrome, which mines on the western limb of Bushveld Igneous Complex, in the North West, encountered a number of failures at the plant owing to inadequate lubrication, incorrect lubrication and dirty oil on critical components such as gearboxes and bearings.

As a result of these failures, Hernic Ferrochrome contracted Filter Focus to run comprehensive oil analyses and con- dition monitoring, whereby all critical components within the plant were fitted with sampling points. The oil analysis programme enabled Filter Focus to identify problem areas and recommend the correct solution before any further costly failures occurred.

“Hernic Ferrochrome is a pioneer in the conversion of semiclosed and open furnaces into closed furnaces in South Africa and currently operates four furnaces, including two 37 MVA closed furnaces, a 54 MVA closed furnace and a 78 MVA closed furnace – one of the world’s largest ferrochrome smelters,” says Hernic Ferrochrome plant manager Jannie Mostert.

Meanwhile, Filter Focus business development officer Brendon Savage explains that the company’s involvement with Hernic Ferrochrome initially began through the implementation of a basic lubrication programme and evolved to include the supply of specialised Filter Focus filtration units and automatic lubricators for critical equipment.

In May 2012, Filter Focus installed automatic lubricators for the majority of conveyor systems at the plant, which currently provide frequent and exact quantities of lubricant for critical bearings. Mostert says that, since these systems have been installed, bearing failures have decreased dramatically, which has led to reduced unscheduled downtime.

With regard to the lubrication of the girth gears, pinion bearings, trunion bearings and gearboxes of pelletising and sinter plants (PSes) 1 and 2, Mostert says that, since the introduction of Lubrication Engineers’ Pyroshield, overall lubrication consumption has been reduced from 400 kg/m to 60 kg/m, equating to an 85% reduction in consumption.

“In addition to a reduction in lubricant consumption, there was also a significant reduction in vibration, a 20% reduction in temperature across the girth gear face and a 22% reduction across the pinion gear face,” he points out.

Since being treated with Lubrication Engineers’ Almagard, the pinion bearings used at PS1 and PS2 have shown a reduction in vibration and temperature of about 12%.

“Filter Focus’s Almagard lubricant has been approved as the only lubricant with advanced-friction coefficiency. It dramatically lengthens grease intervals, eliminates bearing failures, extends bearing life by up to threefold and does not harden with age,” highlights FitzGerald.

Hernic Ferrochrome also had problems with its smelter fans and used the LE Monolec lubricant as a possible solution.

“The day we decided to apply LE Monolec lubricant to the bearing of the furnace preheat exhaust fans was when we received fan number five for smelter four back from repairs. Generally, when you start up a new fan or a new bearing assembly, the operating temperature initially increases and then decreases after roughly six to eight hours. In this case, the bearing temperatures simply weren’t decreasing.

“Filter Focus suggested running the fan on LE Monolec lubricant. That same night, we received the oil from Filter Focus, poured it into the machine and witnessed the temperature drop from 95 ºC to 75 ºC within 30 minutes. It then stabilised to about 50 ºC. We have been running Monolec lubricant on all of our furnace preheat exhaust fans ever since,” says Mostert.

However, FitzGerald mentions that the company’s biggest challenge remains trying to convince mines to incorporate lubricants in their maintenance plan, despite lubricants’ proved record in cost savings.

“We try to talk to engineers and show them the efficiency of applying lubrication on equipment at various plants. In doing that, we have realised that the lack of under- standing is what has resulted in industry not using lubrication as a cost-effective measure. However, we continue to meet with different engineers and make them aware of the benefits of lubrication and oil filtration by presenting case studies of the work we have done at different mines,” he concludes.