Unplanned maintenance, downtime or a need to unexpectedly change a hydraulic filter element is not an option in any underground mining operation. Today, proper hydraulic maintenance has become even more critical because the mining industry is facing the toughest operating environment in its history. Managing both cost and improving system performance are key factors dictating the survival of many mining companies.
Schroeder Industries is well known in the mining industry for its filtration and hydraulic diagnostic systems. Schroeder Brothers Corp. started in 1946 as a mining products distribution company and evolved into a mining focused hydraulic systems manufacturer. As the company ventured into systems production, many of which were PTO driven and designed with more sophisticated valve solutions, it developed a number of high-quality, high-performance filtration products to ensure their proper operation and continues to do so today with its Advanced Fluid Conditioning Solutions.
Small change, big impact
With the ever-changing nature of the mining industry, mining companies are more focused than ever on achieving real cost savings and uptime efficiency. One of Schroeder’s key accounts in the Appalachian region has used a strategic sourcing program to significantly improve its hydraulic system performance, its hydraulic maintenance procedures and, in turn, both its purchased and operating costs.
This mining company did something that for many is a simple change—but much more challenging in the demanding conditions encountered by mine operators. Starting 14 months ago, it departed from the standard industry practice of changing the filter based on a very tight, very regimented time line. So instead of changing lower performance hydraulic element product once per week, it switched to the best practice of changing the elements on bypass warning indication, and at the same time upgraded its mining systems when premature indication showed that the original filtration may have been inadequate.
The company has now extended its average hydraulic filter element life from one to four weeks and the plan is to take this change interval to eight weeks on most machines within the next 12 months. In short, by partnering with and committing to better filtration through Schroeder’s Advanced Fluid Conditioning Program, it is better using its resources and achieving more life from the filter, its cartridge-style high performance elements and its operators.
To start, simple changes were made. After an exhaustive vendor review, this mining company quickly realized the real cost of filtration—that not just the up-front purchase cost but total cost of ownership should be considered. Savings also came from the careful evaluation of what portion of the hydraulic systems could be improved, what product quality was required, and what level of program support was required.
Advanced technologies save more in the long run
Next, the mining operator began reviewing the older continuous mining systems and switching these from the low cost cellulose media to the more advanced, and more expensive, higher performing synthetic media and then testing all of the filter housings’ bypass indicators to ensure that they were in working condition. Piloted at one mine and proven, this allowed the company to explain why using the right filters and servicing the elements as intended would protect the hydraulic systems for the longer and critical maintenance service intervals.
On the surface, this seems like a simple change, but it required changing the maintenance process and dictated that the filtration must have the performance to ensure the required system ISO cleanliness code levels. The new elements also needed to guarantee high dirt holding capacity to meet the extended service intervals and needed to deliver the structural integrity to guarantee Beta stability under hydraulic load; in other words, the elements were required to keep the oil clean, last long enough, and not break-down due to repeated high differential pressures during operation.
All of the above performance requirements have become mandatory to guarantee that the elements would perform without fail until the machines could be brought to a location or production stopped at a planned time interval where scheduled maintenance can be performed. Again, safe uptime is everything and unplanned maintenance to change an element cannot stop a mine’s production and this was why in the past there was a strict adherence to the one week time-based change.
To put the significance of this change in context, even the simplest hydraulic system maintenance performed underground—something as easy as changing the filter element—can become a monumental task without preparation. Why? You can’t call the storeroom and just pick one up, nor do you have much room to work. Besides having mere inches of room to change the element, housings are located in the machines to maximize space so even with ergonomic filter placement, the elbow room available in other applications just does not exist. On top of this, the mine is most often wet and hard, so environmental contamination exists throughout the service area. The operators are often dirty from the mining process, lighting is not always the best, and again most importantly, uptime is everything.
A long-term commitment to better hydraulic filtration, better operating performance/more uptime through improved fluid cleanliness, and using the right elements to increase the change intervals has helped this mining company decrease its element usage/costs, and in only 12 months has drastically improved its hydraulic operating cost savings and improved the uptime on the mining equipment. But this isn’t the end. Once every operating mine is ready, the goal is to eventually reduce the hydraulic oil drain intervals and significantly reduce fluid loss caused by the wear particles in the fluid system.