Mining and Minerals

Filtration in hydraulic circuits

In order to ensure the failure-free operation of hydraulic systems underground, it is essential that the medium is not simply filtered at one point, but is continually cleaned throughout the entire circuit. Thus, return filters, that clean the fluid coming from the mining machines, are essential parts of the circuit. Return filtration is often carried out in two stages that are individually adapted to the respective application. In the first stage, an economical and effective pre-filter retains the larger part of any impurities, while in the second, our Long-Life elements ensure the provision of a fluid that meets the specified level of purity.

In addition to high-pressure and return flow filtration, bypass filters help to keep hydraulic fluid in the tank clean and in motion at all times.

Sprinkling water filtration

A shearer loader must not be operated without continuous water sprinkling, otherwise the system will overheat and unacceptable dust generation will occur. At this point particle filtration is indispensable in order to ensure the continuous functionality of the sprinkling system and to prevent blockage of the nozzles.

Filters for sprinkling water are manually or automatically backflushable systems in a compact design, which are ideally adapted to hydraulic conditions and pressure at the point of use. This also applies to the sprinkling water filtration in the new Water Spray Technology, developed at Southern Illinois University Carbondale (USA), and has just entered the market. This new sprinkling water system can reduce generated coal dust by up to 60 %.

In addition to sprinkling, water is also used for cooling the shearer loader’s two motors. The operability of both motors, one of which drives the shearer drum and the other the machine itself, is maintained by effective water filtration. We deliver filters for this application that are individually adapted to the spatial conditions in the motor compartments. High volume flows through filter surfaces with small external dimensions is achieved through the use of integrated flow optimization.

Filtration at the planer

Planers, scalping mining machines, are employed as an alternative to shearer loaders, which cut the material to be extracted. Water is used for cooling and dust suppression here as well. Safe continuous operation is ensured by means of inline filters, as well as by manually or automatically operated back-flush filter systems.

Tank filtration

In addition to high-pressure and backflow filtration, bypass filters at the hydraulic oil and finished hydraulic fluid tanks help to ensure that the fluids in the tanks are kept clean and in motion. Likewise, the water and hydraulic oil involved are filtered before they enter the fluid mixing plant.

Return filtration

In order to ensure the failure-free operation of hydraulic systems underground, it is essential that the medium is not simply filtered at one point, but is continually cleaned throughout the entire circuit. Thus, return filters, that clean the fluid coming from the mining machines, are essential parts of the circuit. Return filtration is often carried out in two stages that are individually adapted to the respective application. In the first stage, an economical and effective pre-filter retains the larger part of any impurities, while in the second, our Long-Life elements ensure the provision of a fluid that meets the specified level of purity.

Filtration at the safety shields

In underground mining, all excavated hollow spaces must be supported against the soil or rock layers above them to prevent collapses and danger to people and machinery. In modern mines, hydraulically-operated, self-propelled roof support shields are used, which follow the mining machine and are directly adjusted to the respective height of the seam.

Depending on the length of the shield alignment the supports can be controlled hydraulically, electro-hydraulically, or electrically. All hydraulic fluids used in the roof support shields are continuously filtered. This is done by in-line filters and back-flush filters which are applied directly at the point of use. The selection of filters and the type of back-flushing are individually adapted to the required face height.