RMZ – MATERIALI IN GEOOKOLJE

438 Kos, A., Dervarič, E.Before the beginning of each cuttingoperation, it takes the operators approximatelytwo hours to prepare themachines, set the blade in a horizontalposition and to rotate the cutting elements.Before every movement of themachine, it is required to disconnectand arrange the hydraulic hoses. Whenmaking the first sections in a gallery,where fixation of pillars in the ceilingis not possible, stabilisation by meansof chains is required. Problems mayoccur in the event of crumbling of thefront section, with numerous instancesof damage to the pillars.Models of chain saw cutting machinesare very different. Types of machinesdepend on the customers’ requirements.There are several models of chain sawcutting machines. The machines aredistinguished from each other by theirintended use, cutting characteristics,dimensions and their electrical andhydraulic equipment. The newer machineshave certain additional features:• the machine’s mobility,• increased cutting height,• the shape of the blade, an automaticblade levelling function has beenadded,• faster movement in larger cuttingwidths,• possible cutting of the back cut ofan advance section,• elimination of deficiencies of hydrauliccables,• a computer to monitor the cuttingparameters,• remote control of the machine.• the weight of the machines allowseasier start in making the first sectionsin a gallery.With the new Fantini 70 GU/R machine,the deficiencies have been eliminatedand improved. The comparison of theresults between the machines G.70 and70 GU/R is given in the table 1.By introducing a new Fantini GU 70/Rchain saw cutting machine, the companyMarmor, Sežana, d. d., has acquireda machine of high quality and high performance.Compared to the old model,G.70, the minimum advance section(5.6 m × 4.5 m × 2.8 m) has been increasedin height from 4.5 m to 5.2 mand in depth from 2.8 m to 3.0 m, thusharvesting by 20 % more material froma minimum advance section than byusing the old model. Both the old andthe new machine can be used to immediatelystart cutting the maximumwidth of a gallery. With the new chainsaw cutting machine, approximatelyseven working days are required for anadvance section of approximate size of150 m 3 ; with the older G.70 model, atleast nine working days were required.The only problem that occurred wasthe construction of initial crossroads ina gallery, as the length of the new machineprevented its positioning in thedirection of advancement. Therefore,we had to position the machine diago-RMZ-M&G 2012, 59