Influence of physico-mechanical characteristics of rocks on efficiency of rotary percussion drilling : master’s thesis

Na površinskim kopovima „Hruškovec“ i “Straža-Vinceli” obavljena su terenska mjerenja efektivne brzine bušenja minskih bušotina, površinskim bušilicama. Uz mjerenje vremena i dubine prodiranja bušaćeg alata, praćeni su i bilježeni tlakovi hidrauličnog ulja i komprimiranog zraka na stroju za bušenje, kao i izmjena litoloških članova tijekom bušenja. Na eksploatacijskom polju „Hruškovec“ izvedeno je mjerenje tijekom bušenja u dijabazu, bušilicom Atlas Copco ROC F6, koja kao radni alat koristi dubinski bušaći čekić. Mjerenje brzine bušenja u vapnencu izvedeno je na eksploatacijskom polju “Straža-Vinceli”, bušilicom Atlas Copco ROC D7 koja kao radni alat koristi vanjski, hidraulički bušaći čekić. Izmjerene brzine bušenja uspoređene su sa teoretskim izračunima brzine bušenja. Detaljno je opisan razvoj i današnje mogućnosti strojeva koji se najčešće koriste za bušenje minskih bušotina u kamenolomima. Obrađeni su i prikazani rezultati jedne studije koji se temelje na ispitivanju osam različitih vrsta stijena na površinskim kopovima i cestovnim trasama. U rezultatima su prikazane korelacije između brzine bušenja i fizikalno mehaničkih svojstava stijena. Jednoosna tlačna čvrstoća, Schmidtova tvrdoća, vlačna čvrstoća (brazilski test) i čvrstoća kod opterećenja u toĉki (PLT – test) svojstva su stijena koja su pokazala najveći utjecaj na brzinu prodiranja bušaćeg alata. Utvrđen je također slabiji utjecaj modula elastičnosti i gustoće, dok brzina širenja P-valova nije iskazala nikakav utjecaj na brzinu bušenja.Abstract: The penetration rate measurements with the surface drills were carried out on the open pits „Hruškovec“ and „Straţa-Vinceli“. Beside measuring time and depth of the drilling tool penetration, the drilling machine hydraulic oil and compresed air pressure were monitored and recorded, as well as changes in lithology. On the exploitation field „Hruškovec“ the measurements were carried out during the drilling in the diabase with the Atlas Copco ROC F6 drilling machine, which as a working tool uses (DTH) down the hole drilling hammer. Drilling speed measurements in limestone were carried out on the exploitation field „Straţa-Vinceli” with the Atlas Copco ROC D7 drilling machine which as a working tool uses top hammer. The measurement results where compared against the theoretical calculations. Furthermore, the detailed development and capabilities of today's drilling machines are described. Also, in this thesis the results of a study which was based on an examination of eight different types of rocks are shown and analyzed. The results have shown the correlation between the penetration rate and the physical mechanical properties of the rocks. Uniaxial compressive strength, Schmidt hardness, tensile strength (Brazilian test) and point load strength showed a strong influence on the rate of penetration of the drilling tool, while lower influence was found between the penetration rate and the modulus of elasticity and the natural density. Influence of the P-wave spreading speed were not found

Influence of physico-mechanical characteristics of rocks on efficiency of rotary percussion drilling : master’s thesis

Na površinskim kopovima „Hruškovec“ i “Straža-Vinceli” obavljena su terenska mjerenja efektivne brzine bušenja minskih bušotina, površinskim bušilicama. Uz mjerenje vremena i dubine prodiranja bušaćeg alata, praćeni su i bilježeni tlakovi hidrauličnog ulja i komprimiranog zraka na stroju za bušenje, kao i izmjena litoloških članova tijekom bušenja. Na eksploatacijskom polju „Hruškovec“ izvedeno je mjerenje tijekom bušenja u dijabazu, bušilicom Atlas Copco ROC F6, koja kao radni alat koristi dubinski bušaći čekić. Mjerenje brzine bušenja u vapnencu izvedeno je na eksploatacijskom polju “Straža-Vinceli”, bušilicom Atlas Copco ROC D7 koja kao radni alat koristi vanjski, hidraulički bušaći čekić. Izmjerene brzine bušenja uspoređene su sa teoretskim izračunima brzine bušenja. Detaljno je opisan razvoj i današnje mogućnosti strojeva koji se najčešće koriste za bušenje minskih bušotina u kamenolomima. Obrađeni su i prikazani rezultati jedne studije koji se temelje na ispitivanju osam različitih vrsta stijena na površinskim kopovima i cestovnim trasama. U rezultatima su prikazane korelacije između brzine bušenja i fizikalno mehaničkih svojstava stijena. Jednoosna tlačna čvrstoća, Schmidtova tvrdoća, vlačna čvrstoća (brazilski test) i čvrstoća kod opterećenja u toĉki (PLT – test) svojstva su stijena koja su pokazala najveći utjecaj na brzinu prodiranja bušaćeg alata. Utvrđen je također slabiji utjecaj modula elastičnosti i gustoće, dok brzina širenja P-valova nije iskazala nikakav utjecaj na brzinu bušenja.Abstract: The penetration rate measurements with the surface drills were carried out on the open pits „Hruškovec“ and „Straţa-Vinceli“. Beside measuring time and depth of the drilling tool penetration, the drilling machine hydraulic oil and compresed air pressure were monitored and recorded, as well as changes in lithology. On the exploitation field „Hruškovec“ the measurements were carried out during the drilling in the diabase with the Atlas Copco ROC F6 drilling machine, which as a working tool uses (DTH) down the hole drilling hammer. Drilling speed measurements in limestone were carried out on the exploitation field „Straţa-Vinceli” with the Atlas Copco ROC D7 drilling machine which as a working tool uses top hammer. The measurement results where compared against the theoretical calculations. Furthermore, the detailed development and capabilities of today's drilling machines are described. Also, in this thesis the results of a study which was based on an examination of eight different types of rocks are shown and analyzed. The results have shown the correlation between the penetration rate and the physical mechanical properties of the rocks. Uniaxial compressive strength, Schmidt hardness, tensile strength (Brazilian test) and point load strength showed a strong influence on the rate of penetration of the drilling tool, while lower influence was found between the penetration rate and the modulus of elasticity and the natural density. Influence of the P-wave spreading speed were not found

CONSTRUCTION AND TESTING OF THE MEASUREMENT SYSTEM FOR EXCAVATOR PRODUCTIVITY

Hidraulični bager jedan je od najčešće korištenih strojeva u rudarstvu, graditeljstvu i geotehnici. Kao takav korisnicima predstavlja i važnu stavku u troškovima goriva i održavanja. Detaljna mjerenja učinka ovoga stroja izvode se u svrhu poboljšanja efikasnosti odnosno uštede. Mjerni sustav s takvom svrhom može biti složen i skup, tražiti specijalnu opremu proizvođača stroja te ne postoji kao gotovo rješenje koje bi omogućavalo praćenje radnih parametara poput trajektorije lopate, sila i energije kopanja, visine radnoga čela i sl. Iz toga razloga osmišljen je i testiran sustav za praćenje radnih parametara i učinka bagera. Sustav se sastoji od triju pretvornika linearnoga pomaka i triju pretvornika tlaka, za mjerenje produljenja i tlakova hidrauličnih cilindara, te jednoga žiroskopa za mjerenje kuta zakretanja bagera. Pretvornici su spojeni na jedinicu za prikupljanje podataka, opremljenu SD karticom i 12-bitnim AD pretvaračem. Jedinica je bazirana na Atmega328 mikrokontroleru, što omogućava primjenu Arduino sučelja za programiranje i razvijenih biblioteka koda. Mjerni sustav testiran je laboratorijski radi određivanja točnosti, rezolucije i moguće brzine uzorkovanja podataka. Tlakovi mogu biti mjereni u rasponu 0 bar – 500 bar s točnošću od 0,026 % MO i rezolucijom 0,15 bar. Izvlačenje cilindra može biti mjereno u rasponu 0 mm – 2300 mm, s točnošću od 0,087 % MO i rezolucijom 0,58 mm. Točnost mjerenja kuta zakretanja iznosi 1,2° po okretu ili 0,33 % MO. Testirana brzina uzorkovanja iznosi 39 Hz – 588 Hz, ovisno o programskome kodu.hydraulic excavator is one of the most used machines in mining, construction and geotechnics. Monitoring its productivity can provide benefits such as savings in fuel consumption and maintenance, cost optimization of working parameters and a higher working efficiency. A measurement system for such a purpose can be complex and expensive, as it requires special equipment from the manufacturer and does not exist as an out of the box solution that would measure working parameters such as bucket trajectory, digging energy, digging force, etc. A measuring system was designed to monitor productivity and gather working parameters. It consists of three pressure transmitters for measuring cylinder pressures, three draw wire sensors for cylinder elongations, one inertial measurement unit for the measurement of swing angle and one logger unit for data acquisition and storage. The logger unit, equipped with an SD card module and 12-bit AD converter, is based on Atmega328 microcontroller, which allows for the usage of Arduino IDE and already developed libraries. The system was tested in a laboratory to determine its accuracy, resolution and usable sample rate. Cylinder pressure can be measured in the range of 0-500 bar with an excellent accuracy of 0.026 % FSO and 0.15 bar resolution. Cylinder elongation can be measured in the range 0-2300 mm with an accuracy of 0.087 % FSO and 0.58 mm resolution. Swing angle measurement accuracy is 1.2° per circle or 0.33 % FSO. The usable sample rate of the system is found to be 39 Hz-588 Hz, depending on the logger executing code

Decreasing of the air humidity by the ventilation control in the St. Barbara mine

The St. Barbara mine is a visitor mine having a large amount of timbering support which is deteriorating fast due to the high humidity conditions. The air conditioning system of mining is not suitable and also expensive for implementation in a shallow non-productive mine. As there are no usual air contaminants in the visitor mines, ventilation could be powered only when a dew point of outside air is below the strata temperature. Applying this rule would certainly avoid condensation, but also raises a potential for partial dehumidification of mine walls as moisture can evaporate in these conditions. A microclimate analysis, based on one-year data, has showed that these favorable conditions of the outside air occur through the major part of the year. Their availability is mostly 100%, but during summertime there are periods when it drops down to 13%. A real time monitoring system with programable microcontroller allows the automatic ventilation control and adjustment to the psychrometric conditions

Klorirani spojevi u mišićnom tkivu riba iz istočnog Jadranskog mora: preliminarni podaci o zagađenosti i zdravstvenim rizicima

Levels of 17 polychlorinated biphenyl congeners (PCBs) and seven organochlorine pesticides (OCPs) were measured in the muscle tissue of 18 commercially important fish species from the eastern Adriatic Sea. PCBs [˂LOD-8,866 ng g-1 lipid weight (lw)] accounted for over 66 % of all analysed compounds. Their pattern was dominated by PCB-138 and PCB-153. DDE (14.2-649 ng g-1 lw) was the prevalent DDT isomer in all samples, suggesting no recent DDT input. β-, γ- and α-HCH and HCB were found in less than 50 % of samples. The analysed organic contaminants did not seem to bioaccumulate up the food web (trophic levels 3.0 to 4.5). Our findings show no risk of chronic (non-cancerous) effects on human health.Maseni udjeli 17 poliklorbifenila (PCB) i 7 organoklorovih pesticida (OCP) izmjereni su u mišićnom tkivu 18 komercijalno važnih ribljih vrsta iz istočnog Jadranskog mora. Maseni udjeli PCB-a (˂LOD do 8.866 ng g-1 masti) činili su više od 66 % svih analiziranih spojeva. U njihovu profilu PCB-138 i PCB-153 dominantni su kongeneri. DDE (14,2-649 ng g-1 masti), glavni izomer DDT-a, jedini je detektiran u svim uzorcima. U manje od 50 % analiziranih uzoraka nađeni su β-, γ- i α-HCH te HCB. U rasponu trofičkih razina analiziranih vrsta (3,0-4,5) nije bilo bioakumulacije organskih zagađivala u hranidbenom lancu. Rezultati procjene rizika za ljudsko zdravlje pokazali su da nema rizika od kroničnih (nekancerogenih) utjecaja na ljudsko zdravlje

The influence of rock material properties on excavator productivity and optimal operating parameters : doctoral dissertation

Hidraulički bager jedan je od najčešće korištenih strojeva u rudarstvu te zbog toga postoji veliki interes istraživača za proučavanjem njegovoga učinka i optimizacije rada. Istraživanje u okviru ovog rada zasniva se na detaljnom proučavanju rada bagera u realnim uvjetima. Takva su istraživanja, prema dostupnoj literaturi, relativno skromna te postoji veliki prostor za napredak. Kako bi se pristupilo podatcima koji pružaju uvid u realni rad bagera potrebno je kontinuirano mjerenje produljenja i tlakova na hidrauličkim cilindrima. To je ostvareno pomoću specifičnoga mjernog sustava kojim se izvodi simultano mjerenje većeg broja parametara na bageru pri radu u realnim uvjetima. Izmjereni podatci obrađeni su pomoću računalnoga programa napisanoga u programskom jeziku Python. Pomoću standardnih kinematičkih i dinamičkih modela bagera dobivene su vrijednosti dinamičkih veličina rada (sila, snaga i utrošak energije pri kopanju) te geometrijskih veličina kopanja (kut upada zuba, duljina i površina reza). Terenska mjerenja izvedena su na pet različitih modela bagera te ukupno trinaest materijala. Laboratorijskim i terenskim ispitivanjima utvrđene su značajke materijala (granulacija, sadržaj vlage i nasipna gustoća). U radu je proračunat učinak kopanja koji predstavlja masu ili volumen iskopanog materijala u vremenu koje je bilo potrebno za izvođenje kopanja. U okviru statističke obrade podataka izvedene su višestruke regresijske analize utjecaja značajki materijala na dinamičke veličine rada bagera i geometriju kopanja. Regresijskom analizom također je prikazan utjecaj karakteristika materijala i geometrije kopanja na učinak. Utvrđeno je da granulometrijski sastav rastresitih materijala predstavlja najutjecajnije svojstvo na učinak kopanja, dok je duljina trajektorije kopanja najutjecajnija geometrijska veličina. Detaljnom analizom zasebnih ciklusa rada bagera utvrđena je razlika optimalne trajektorije kopanja u različitim materijalima. Predložena je klasifikacija učinka kopanja bagera u različitim materijalima. Također je predložen model za procjenu značajki materijala na temelju dinamičkih veličina rada bagera.The hydraulic excavator is one of the most commonly used machines in mining. Because of this, researchers have a great interest in studying its productivity and optimization of work. The research within this work is based on a detailed study of the operation of an excavator in real conditions. According to the available literature, such research is relatively modest and there is a lot of room for improvement. In order to access the data that provides insight into the real operation of the excavator, it is necessary to continuously measure the extension and pressures on the hydraulic cylinders. This is achieved by using a specific measuring system that can perform a simultaneous measurement of several parameters on the excavator during its work in real conditions. The measured data was processed using a computer program written in the Python programming language. Using standard kinematic and dynamic models of excavators, values of dynamic parameters of work (force, power, and energy consumption during digging) and geometric parameters of digging (tooth angle, length, and cutting area) were obtained. The field measurements were performed on 5 different machines and a total of 13 materials. Laboratory and field measurements determined the characteristics of the material (granulation, moisture content, and bulk density). In the paper, the productivity of digging was calculated, which represents the mass or volume of the excavated material in the time it took to perform the digging. In the frame of the statistical processing of data, multiple regression analyses have been performed on the influence of the characteristics of the material on the dynamic parameters of the excavator and the digging geometry. By regression analysis, the influence of the characteristics of the rocks and the geometry of digging on the productivity of digging are also shown. The size distribution has been found to be the most influential property of non-cohesive materials on the productivity of digging, while the length of the digging trajectory is the most influential geometric size. Through detailed analysis of the separate work cycles of the excavators, the difference in optimal digging trajectory in different materials has been determined. The classification of productivity of excavators digging in different materials is proposed. A model for assessing the characteristics of the materials based on the dynamic working parameters of the excavator is also proposed

The influence of rock material properties on excavator productivity and optimal operating parameters : doctoral dissertation

Hidraulički bager jedan je od najčešće korištenih strojeva u rudarstvu te zbog toga postoji veliki interes istraživača za proučavanjem njegovoga učinka i optimizacije rada. Istraživanje u okviru ovog rada zasniva se na detaljnom proučavanju rada bagera u realnim uvjetima. Takva su istraživanja, prema dostupnoj literaturi, relativno skromna te postoji veliki prostor za napredak. Kako bi se pristupilo podatcima koji pružaju uvid u realni rad bagera potrebno je kontinuirano mjerenje produljenja i tlakova na hidrauličkim cilindrima. To je ostvareno pomoću specifičnoga mjernog sustava kojim se izvodi simultano mjerenje većeg broja parametara na bageru pri radu u realnim uvjetima. Izmjereni podatci obrađeni su pomoću računalnoga programa napisanoga u programskom jeziku Python. Pomoću standardnih kinematičkih i dinamičkih modela bagera dobivene su vrijednosti dinamičkih veličina rada (sila, snaga i utrošak energije pri kopanju) te geometrijskih veličina kopanja (kut upada zuba, duljina i površina reza). Terenska mjerenja izvedena su na pet različitih modela bagera te ukupno trinaest materijala. Laboratorijskim i terenskim ispitivanjima utvrđene su značajke materijala (granulacija, sadržaj vlage i nasipna gustoća). U radu je proračunat učinak kopanja koji predstavlja masu ili volumen iskopanog materijala u vremenu koje je bilo potrebno za izvođenje kopanja. U okviru statističke obrade podataka izvedene su višestruke regresijske analize utjecaja značajki materijala na dinamičke veličine rada bagera i geometriju kopanja. Regresijskom analizom također je prikazan utjecaj karakteristika materijala i geometrije kopanja na učinak. Utvrđeno je da granulometrijski sastav rastresitih materijala predstavlja najutjecajnije svojstvo na učinak kopanja, dok je duljina trajektorije kopanja najutjecajnija geometrijska veličina. Detaljnom analizom zasebnih ciklusa rada bagera utvrđena je razlika optimalne trajektorije kopanja u različitim materijalima. Predložena je klasifikacija učinka kopanja bagera u različitim materijalima. Također je predložen model za procjenu značajki materijala na temelju dinamičkih veličina rada bagera.The hydraulic excavator is one of the most commonly used machines in mining. Because of this, researchers have a great interest in studying its productivity and optimization of work. The research within this work is based on a detailed study of the operation of an excavator in real conditions. According to the available literature, such research is relatively modest and there is a lot of room for improvement. In order to access the data that provides insight into the real operation of the excavator, it is necessary to continuously measure the extension and pressures on the hydraulic cylinders. This is achieved by using a specific measuring system that can perform a simultaneous measurement of several parameters on the excavator during its work in real conditions. The measured data was processed using a computer program written in the Python programming language. Using standard kinematic and dynamic models of excavators, values of dynamic parameters of work (force, power, and energy consumption during digging) and geometric parameters of digging (tooth angle, length, and cutting area) were obtained. The field measurements were performed on 5 different machines and a total of 13 materials. Laboratory and field measurements determined the characteristics of the material (granulation, moisture content, and bulk density). In the paper, the productivity of digging was calculated, which represents the mass or volume of the excavated material in the time it took to perform the digging. In the frame of the statistical processing of data, multiple regression analyses have been performed on the influence of the characteristics of the material on the dynamic parameters of the excavator and the digging geometry. By regression analysis, the influence of the characteristics of the rocks and the geometry of digging on the productivity of digging are also shown. The size distribution has been found to be the most influential property of non-cohesive materials on the productivity of digging, while the length of the digging trajectory is the most influential geometric size. Through detailed analysis of the separate work cycles of the excavators, the difference in optimal digging trajectory in different materials has been determined. The classification of productivity of excavators digging in different materials is proposed. A model for assessing the characteristics of the materials based on the dynamic working parameters of the excavator is also proposed

The influence of rock material properties on excavator productivity and optimal operating parameters : doctoral dissertation

Hidraulički bager jedan je od najčešće korištenih strojeva u rudarstvu te zbog toga postoji veliki interes istraživača za proučavanjem njegovoga učinka i optimizacije rada. Istraživanje u okviru ovog rada zasniva se na detaljnom proučavanju rada bagera u realnim uvjetima. Takva su istraživanja, prema dostupnoj literaturi, relativno skromna te postoji veliki prostor za napredak. Kako bi se pristupilo podatcima koji pružaju uvid u realni rad bagera potrebno je kontinuirano mjerenje produljenja i tlakova na hidrauličkim cilindrima. To je ostvareno pomoću specifičnoga mjernog sustava kojim se izvodi simultano mjerenje većeg broja parametara na bageru pri radu u realnim uvjetima. Izmjereni podatci obrađeni su pomoću računalnoga programa napisanoga u programskom jeziku Python. Pomoću standardnih kinematičkih i dinamičkih modela bagera dobivene su vrijednosti dinamičkih veličina rada (sila, snaga i utrošak energije pri kopanju) te geometrijskih veličina kopanja (kut upada zuba, duljina i površina reza). Terenska mjerenja izvedena su na pet različitih modela bagera te ukupno trinaest materijala. Laboratorijskim i terenskim ispitivanjima utvrđene su značajke materijala (granulacija, sadržaj vlage i nasipna gustoća). U radu je proračunat učinak kopanja koji predstavlja masu ili volumen iskopanog materijala u vremenu koje je bilo potrebno za izvođenje kopanja. U okviru statističke obrade podataka izvedene su višestruke regresijske analize utjecaja značajki materijala na dinamičke veličine rada bagera i geometriju kopanja. Regresijskom analizom također je prikazan utjecaj karakteristika materijala i geometrije kopanja na učinak. Utvrđeno je da granulometrijski sastav rastresitih materijala predstavlja najutjecajnije svojstvo na učinak kopanja, dok je duljina trajektorije kopanja najutjecajnija geometrijska veličina. Detaljnom analizom zasebnih ciklusa rada bagera utvrđena je razlika optimalne trajektorije kopanja u različitim materijalima. Predložena je klasifikacija učinka kopanja bagera u različitim materijalima. Također je predložen model za procjenu značajki materijala na temelju dinamičkih veličina rada bagera.The hydraulic excavator is one of the most commonly used machines in mining. Because of this, researchers have a great interest in studying its productivity and optimization of work. The research within this work is based on a detailed study of the operation of an excavator in real conditions. According to the available literature, such research is relatively modest and there is a lot of room for improvement. In order to access the data that provides insight into the real operation of the excavator, it is necessary to continuously measure the extension and pressures on the hydraulic cylinders. This is achieved by using a specific measuring system that can perform a simultaneous measurement of several parameters on the excavator during its work in real conditions. The measured data was processed using a computer program written in the Python programming language. Using standard kinematic and dynamic models of excavators, values of dynamic parameters of work (force, power, and energy consumption during digging) and geometric parameters of digging (tooth angle, length, and cutting area) were obtained. The field measurements were performed on 5 different machines and a total of 13 materials. Laboratory and field measurements determined the characteristics of the material (granulation, moisture content, and bulk density). In the paper, the productivity of digging was calculated, which represents the mass or volume of the excavated material in the time it took to perform the digging. In the frame of the statistical processing of data, multiple regression analyses have been performed on the influence of the characteristics of the material on the dynamic parameters of the excavator and the digging geometry. By regression analysis, the influence of the characteristics of the rocks and the geometry of digging on the productivity of digging are also shown. The size distribution has been found to be the most influential property of non-cohesive materials on the productivity of digging, while the length of the digging trajectory is the most influential geometric size. Through detailed analysis of the separate work cycles of the excavators, the difference in optimal digging trajectory in different materials has been determined. The classification of productivity of excavators digging in different materials is proposed. A model for assessing the characteristics of the materials based on the dynamic working parameters of the excavator is also proposed

Influence of physico-mechanical characteristics of rocks on efficiency of rotary percussion drilling : master’s thesis

Na površinskim kopovima „Hruškovec“ i “Straža-Vinceli” obavljena su terenska mjerenja efektivne brzine bušenja minskih bušotina, površinskim bušilicama. Uz mjerenje vremena i dubine prodiranja bušaćeg alata, praćeni su i bilježeni tlakovi hidrauličnog ulja i komprimiranog zraka na stroju za bušenje, kao i izmjena litoloških članova tijekom bušenja. Na eksploatacijskom polju „Hruškovec“ izvedeno je mjerenje tijekom bušenja u dijabazu, bušilicom Atlas Copco ROC F6, koja kao radni alat koristi dubinski bušaći čekić. Mjerenje brzine bušenja u vapnencu izvedeno je na eksploatacijskom polju “Straža-Vinceli”, bušilicom Atlas Copco ROC D7 koja kao radni alat koristi vanjski, hidraulički bušaći čekić. Izmjerene brzine bušenja uspoređene su sa teoretskim izračunima brzine bušenja. Detaljno je opisan razvoj i današnje mogućnosti strojeva koji se najčešće koriste za bušenje minskih bušotina u kamenolomima. Obrađeni su i prikazani rezultati jedne studije koji se temelje na ispitivanju osam različitih vrsta stijena na površinskim kopovima i cestovnim trasama. U rezultatima su prikazane korelacije između brzine bušenja i fizikalno mehaničkih svojstava stijena. Jednoosna tlačna čvrstoća, Schmidtova tvrdoća, vlačna čvrstoća (brazilski test) i čvrstoća kod opterećenja u toĉki (PLT – test) svojstva su stijena koja su pokazala najveći utjecaj na brzinu prodiranja bušaćeg alata. Utvrđen je također slabiji utjecaj modula elastičnosti i gustoće, dok brzina širenja P-valova nije iskazala nikakav utjecaj na brzinu bušenja.Abstract: The penetration rate measurements with the surface drills were carried out on the open pits „Hruškovec“ and „Straţa-Vinceli“. Beside measuring time and depth of the drilling tool penetration, the drilling machine hydraulic oil and compresed air pressure were monitored and recorded, as well as changes in lithology. On the exploitation field „Hruškovec“ the measurements were carried out during the drilling in the diabase with the Atlas Copco ROC F6 drilling machine, which as a working tool uses (DTH) down the hole drilling hammer. Drilling speed measurements in limestone were carried out on the exploitation field „Straţa-Vinceli” with the Atlas Copco ROC D7 drilling machine which as a working tool uses top hammer. The measurement results where compared against the theoretical calculations. Furthermore, the detailed development and capabilities of today's drilling machines are described. Also, in this thesis the results of a study which was based on an examination of eight different types of rocks are shown and analyzed. The results have shown the correlation between the penetration rate and the physical mechanical properties of the rocks. Uniaxial compressive strength, Schmidt hardness, tensile strength (Brazilian test) and point load strength showed a strong influence on the rate of penetration of the drilling tool, while lower influence was found between the penetration rate and the modulus of elasticity and the natural density. Influence of the P-wave spreading speed were not found