Discussion on bulk carrier loading and unloading operations and freight safety for the owner's and master's responsibilities and ... Hu SP, Jin YX, et al. Performance simulation of the transportation process risk of bauxite carriers based on the Markov Chain and Cloud model. J Mar Sci Eng 2019; 7(4): 116. Crossref. Google Scholar. 7. ...
WhatsApp: +86 18203695377The process of loading and unloading can involve heavy equipment, moving machinery, and manual labor, which increases the risk of accidents and injuries. It is crucial to provide comprehensive training, enforce safety protocols, and use proper personal protective equipment to minimize these risks. 2. Damage to cargo and vessel.
WhatsApp: +86 18203695377To study the anisotropic mechanical properties and energy evolution of layered rock masses under the action of cyclic loading, uniaxial graded cyclic loading and unloading tests under different upper and lower stress limits were carried out on samples with different bedding angles (0°, °, 45°, °, and 90°) to explore the deformation and mechanical response characteristics of bedded ...
WhatsApp: +86 18203695377Mining under the sea is a challenging task in China. Affected by blasting, tunneling, and other engineering disturbance, surrounding rock is often in a state of cyclic loading and unloading stress. In this study, in order to investigate the effect of cyclic loading and unloading on the deformation and damage characteristics of sandstone underneath the Bohai Sea, the GCTS test machine is used ...
WhatsApp: +86 18203695377Conventional and cyclic unloading tests with different unloading rates were conducted to study the influences of unloading patterns and rates on the deformation characteristics and mechanical properties of tectonic coal. The results demonstrate that, under continuous unloading, a lower unloading rate promotes an increase in the circumferential strain but inhibits increases in axial strain.
WhatsApp: +86 18203695377A semicontinuous process system consisting of a singlebucket excavator, truck, crushing station, and belt conveyor is the main coal mining process system of a largescale hard coal openpit mine. Through analyzing the coal mining production process, the key issues of coal mining truck flow optimization are obtained. Statistical method of using triangular fuzzy numbers analyzes the key time ...
WhatsApp: +86 18203695377Given the roadway deformation and surrounding rock control in the process of thin coal seam mining, the coalrock combination with inclination angles for 0°, 15°, 30°, 45°, and 60° was designed. The rock mechanic test machine was used to conduct a uniaxial compression test and a graded loading and unloading test on the coalrock combination; the failure characteristics of the two were ...
WhatsApp: +86 18203695377The process of rock cycle loading and unloading results in the external force constantly performing work on the specimen. The external force is converted into elastic strain and dissipation energy. Using the principles of thermodynamics, energy transformation is the essential process by which the energy state of the specimen changes, as ...
WhatsApp: +86 18203695377As a result, the crack of saturated coal samples cannot keep stationary in the initial stage of loading and unloading and it slips throughout the loading and unloading process. A large number of macrotensile cracks appeared in the failed coal samples with pore water, as the pore pressure provides tensile force to the cracks and promotes the ...
WhatsApp: +86 18203695377The working process of the underground coal bunker was actually the loading or unloading of coal for the silo wall. And the stress environment of the silo wall and surrounding rock continually changes, resulting in the deformation of the silo wall under the inner lateral pressure. Stress Analysis
WhatsApp: +86 18203695377In the process of coal seam mining, the coal is disturbed by periodic pressure. This disturbance can be simplified to the loading process under different stress environments [5], [9], [10], [45], and the characteristics of the mining stress path are different under different advancing speeds [46]. Fig. 3 shows the loading path of the sample. M ...
WhatsApp: +86 18203695377In the cyclic loading and unloading process, the load ing and unloading elastic modulus of coal samples experi ences a rapid increase at the beginning stage of the cyclic
WhatsApp: +86 18203695377During the loading/unloading process, the gas pressure in the coal sample is maintained constant through the ingenious structure design of the system. As shown in Fig. 2 b, the constantvolume chamber is connected to the sample by a gas tube, and the constantvolume pistons are connected to the axial indenter.
WhatsApp: +86 18203695377During the cyclic loading and unloading process, assuming that there was no energy exchange between the machine and the external environment, the test equipment transferred energy to the sample through mechanical work, part of which was converted into elastic energy stored inside the coal body, and could be completely released during unloading ...
WhatsApp: +86 18203695377Both coal companies and Railways have envisaged to jointly ensure per day coal loading of 415 rakes of domestic coal and 30 rakes of imported coal to the power sector. 'In the current month ...
WhatsApp: +86 18203695377The rock mass in fault zones is frequently subjected to cyclic loading and unloading during deep resource exploitation and tunnel excavation. Research on the mechanical and hydraulic characteristics of fault rock during the cyclic loading and unloading is of great significance for revealing the formation mechanism of waterconducting pathways in fault and preventing water inrush disasters. In ...
WhatsApp: +86 18203695377Compared with the axial loading rate, the hoop unloading rate is the main reason for the change of the rock failure mode . Ma et al. found that the rapid unloading intensified the damage of coal samples before and after rupture, resulting in a sharp increase in the damage curve. Therefore, in actual production, the excavation speed of coal and ...
WhatsApp: +86 18203695377This is the technology that used in power plant, while the coal is unload to the convayer belt
WhatsApp: +86 18203695377The loadingunloading process is represented as follows: 0 ... In cyclic loading process, the coal samples first exhibit the appearance of microcracks at the beginning stage. With the increase in the axial stress, the damage gradually accumulates and produces irreversible plastic deformation. When the peak load is reached, partial area of ...
WhatsApp: +86 18203695377Coal failure is often the precursor of dynamic disaster. The energy evolution behaviour at different stress values was analysed under the gradation of equal amplitude cyclic loading/unloading. Based on the energy dissipation behaviour, the energy evolution model of the coal specimen was established. The multiparameter energy behaviour predicting model was proposed.
WhatsApp: +86 18203695377Compared with the loading approaches mentioned above, the cyclic loadingunloading testament is an effective approach in revealing the mechanical response of coal and rock under repeated disturbance of excavation, 47, 50, 51 through parameters, such as peak strength, elastic modulus, and energy dissipation features. 33, 47, 48, 52 Though many ...
WhatsApp: +86 18203695377In the unloading process, the fracture space in coal sample extends and expands passively, instead of the compression of fracture under stress loading. The microcracks and beddings in the coal sample gradually connect, the number of gas permeation channels increases, and the rate of gas transport within coal becomes faster.
WhatsApp: +86 18203695377Scholars have examined the mechanical 22,23, the damage 24,25, and the energy characteristics 26,27 of coal under cyclic loading and unloading. In the process of cyclic loading, some scholars ...
WhatsApp: +86 18203695377In order to attain high efficiency, carefully matched loading and unloading terminals are necessary. In one example, a unit train transporting 17,400 tons per 1,200kilometre round trip from mine to plant has a turnaround time of 72 hours—including a 4hour loading and 10hour unloading and servicing time per train. Onhighway trucks
WhatsApp: +86 18203695377During the process of underground mining, roadway excavation and heading face cause the surrounding rock to produce stress disturbance and break the equilibrium state of coal and rock, which is usually manifested as axial loading and confining pressure unloading. This phenomenon is more obvious during the deep mining of coal and rock.
WhatsApp: +86 18203695377True triaxial loadingunloading tests of coal samples were performed using a multifunctional true triaxial fluidsolid coupling experimental system. The deformation, seepage, damage, strength, and failure characteristics of the coal samples were analyzed. Based on this, the variation mechanism of the permeability and yield conditions under different gas pressures was investigated, and the ...
WhatsApp: +86 18203695377Coal mining leads to stress loadingunloading variation in front of the working face, which influences the occurrence of disasters. In order to study the influence mechanism of stress loadingunloading to the coal failure, a series of experiments of gasbearing coal deformation and failure under triaxial stress were conducted and acoustic emission (AE) was monitored.
WhatsApp: +86 18203695377The residual strains has produced by the first loadingunloading of coal are 7 × 10 −5, × 10 −4, and × 10 −4, respectively. ... However, if the loadingunloading process was continued beyond this point, the residual strain reappeared. The occurrence of the nonresidual strain phenomenon was found to be directly related to the ...
WhatsApp: +86 18203695377The coils are then loaded either on a reel style or cradle style uncoiling system. Cradle style uncoilers are relatively easy to load, you basically lower your coil onto the cradle, position the sides guides to center the coil and your coil is ready to be released. On a reel type the process is not as easy. You have a large heavy object either ...
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