Optimum exploitation of deposits, better raw material
In order to ensure that the material extracted from the quarry is as dry as possible, a radical change in the mining method was necessary. Meanwhile, the previous use of explosives for limestone mining was having a detrimental effect on neighboring residential areas due to the noise generated and the ground vibrations. IFCEM found the solution in Wirtgen surface miner technology: In 2012, the company purchased a 2200 SM, in 2015 a second, identical model and in 2017 a 2500 SM.
By gradually phasing out the drilling and blasting operations, the surface miners progressively reduced the time and cost involved in pre-crushing and post-crushing the material and also made it possible to redesign the deposit. By ensuring a defined slope of the surface with the aid of the Level Pro automatic leveling system, the surface miners created the conditions for efficient dewatering.
Compared to drilling and blasting, this allows much drier raw material to be mined and the material can enter the plant's drying process without any further treatment. Thanks to the redesign of the mining area with the surface miner, the exploitation of the deposits has also been increased, because now even previously unused areas can be worked and additional material extracted.
Economical and reliable surface miner trio
The increased mining volume thus also had a major influence on the selection of the third machine model. After the impressive results of the smallest Wirtgen surface miner 2200 SM with a 2.2-m cutting drum and a cutting depth of up to 300 mm, the technical management of Ivano-Frankivskcement now opted for the even more powerful model, the 2500 SM.
Together, the three Wirtgen surface miners generate a daily output of 7,000 tons, which also leads to optimum utilization of the cement plant. The 2500 SM has made an important contribution to this, as well as to increasing production in the limestone quarries, where the material has a uniaxial compressive strength of between 20 and 70 MPa depending on its depth. The 2500 SM, which has already clocked more than 4,500 hours, is equipped with a 2.5 m-wide cutting drum fitted with cutting tools on an HT 15 quick-change tool-holder system. HT 15 reduces the time required to replace the tool-holder from 90 to 15 minutes compared to conventional welded tool-holder systems.
The 2500 SM, which can remove material up to 650 mm deep, extracts the material in Ivano-Frankivsk up to a depth of 40-45 cm. Depending on the rock hardness, the surface miner achieves a feed rate of 5 m per minute and a grain size of 0-100 mm. Depending on the hardness of the rock, the entire tooling is replaced at intervals that vary between 200 and 500 hours based on the machine's field of application.