Drilling and blasting play vital roles in opencast mining. These operations not only affect the cost of production directly but as well and significantly, the overall operational costs. This research was carried out t...Drilling and blasting play vital roles in opencast mining. These operations not only affect the cost of production directly but as well and significantly, the overall operational costs. This research was carried out to find a possible way of optimizing the drilling and blasting operations in an open pit mine of Somair (Société des Mines de l’Air), in the Niger Republic. In order to optimize the drilling operation, the time taken by two drilling machines to accomplish the same task was analyzed statistically. The result indicates that the Down the Hole Hammer Drilling Rig (DMNo406) is more efficient than the Drill Master (DM405). The relative unit consumption of two explosives (Explus and Nitram 9), when used under the same operating conditions, were also considered and the results indicate Explus to be more economical per unit consumption with a range of 0.15 g/t–0.183 g/t, when compared with Nitram 9 with a unit consumption range of 0.19 g/t-0.24 g/t in the study area.展开更多
In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel ...In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel drive shaft, achieved the perfect assemble with transmission structure of the original power unit. It could interconvert according to need by using two sets of drive shafts with direct and reverse circulation. The repacked G-3 engineering driller carried on experiment in the field test in Luanchuan molybdenum mine of Henan, whose effect was very good.展开更多
Based on the calculated results of the simplified model of deep-water semi-submerged drilling unit,the model of deep-water semi-submerged drilling unit is built by reasonably simplifying.The large vertical cylinder(Ma...Based on the calculated results of the simplified model of deep-water semi-submerged drilling unit,the model of deep-water semi-submerged drilling unit is built by reasonably simplifying.The large vertical cylinder(MacCamy-Fuchs)formula is modified according to this model,then the modified formula is utilized to obtain the wave load spectrum which acts on the columns of the semi-submerged drilling unit.By using ANSYS software,a spectrum analysis process is established to calculate the stochastic response spectrum of the model that is subjected to the wave load spectrum which has been calculated.Then the power spectral density of stochastic response of the key nodes can be obtained.Based on the Miner model and the first excursion failure criterion,the fatigue life reliability of the key nodes is calculated.展开更多
文摘Drilling and blasting play vital roles in opencast mining. These operations not only affect the cost of production directly but as well and significantly, the overall operational costs. This research was carried out to find a possible way of optimizing the drilling and blasting operations in an open pit mine of Somair (Société des Mines de l’Air), in the Niger Republic. In order to optimize the drilling operation, the time taken by two drilling machines to accomplish the same task was analyzed statistically. The result indicates that the Down the Hole Hammer Drilling Rig (DMNo406) is more efficient than the Drill Master (DM405). The relative unit consumption of two explosives (Explus and Nitram 9), when used under the same operating conditions, were also considered and the results indicate Explus to be more economical per unit consumption with a range of 0.15 g/t–0.183 g/t, when compared with Nitram 9 with a unit consumption range of 0.19 g/t-0.24 g/t in the study area.
基金Project of Science & Technology Development Guidance of Jilin Province (No.200405033)
文摘In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel drive shaft, achieved the perfect assemble with transmission structure of the original power unit. It could interconvert according to need by using two sets of drive shafts with direct and reverse circulation. The repacked G-3 engineering driller carried on experiment in the field test in Luanchuan molybdenum mine of Henan, whose effect was very good.
基金the National High Technology Research and Development Program (863) of China(No.2006AA09A103)
文摘Based on the calculated results of the simplified model of deep-water semi-submerged drilling unit,the model of deep-water semi-submerged drilling unit is built by reasonably simplifying.The large vertical cylinder(MacCamy-Fuchs)formula is modified according to this model,then the modified formula is utilized to obtain the wave load spectrum which acts on the columns of the semi-submerged drilling unit.By using ANSYS software,a spectrum analysis process is established to calculate the stochastic response spectrum of the model that is subjected to the wave load spectrum which has been calculated.Then the power spectral density of stochastic response of the key nodes can be obtained.Based on the Miner model and the first excursion failure criterion,the fatigue life reliability of the key nodes is calculated.