When advancing in hard rock roadway, compared with conventional blasting, the shaped charge blasting technique could get more ideal blasting effect on the premise of saving blasting material. In this paper, according to the geological and construction conditions of rock roadway with large section in Fourth Mine of Pingdingshan Coal Co.,LTD, and based on the principle of shaped charge blasting technique, we designed new blasting parameters on the original conventional blasting parameters. The shaped charge blasting engineering practice showed that, compared with original parameters, the new parameters could increase the footage by 15% and reduce the amount of overbreak and underbreak on roadway surrounding rock by 50% and save the cost by 20%, and achieve good technology economic results.

The main factors what lead to instability of soft rock tunnel is Groundwater,it weaked the surrouding of roadway quickly and impacted on deformation mechanism of roadway seriously. By analysis of the geological condition and the surrounding environment.the deformation of soft rock roadway cause the change of surrounding rock stress and plastic zone instability,under the coupling of stress field and seepage field.Groundwater induce wall rock mechanics features become bad gradually because of infiltration and force extrusion.The practice shows that strengthen support and draining water can weaken roadway deformation from the roots.

Unbalanced bidding strategies to the contractor in this paper is divided into three categories, namely combine with change, pricing, and claim the unbalanced bidding strategies. The basis of analyses the unbalanced quote: construction contract specifications and the quantities bill valuation, to the contractor unbalanced quotation and pricing changes, and claim combined with imbalance quotation is analyzed. In this paper, the unbalanced bidding strategies, and proposes the corresponding strategies from the Angle of the tenderer.

It has become uncommon that Enterprise Struggled in the difficult even been declared bankrupt due to financial crisis caused by inventory mismanagement. As a common operation risk in business, how to conduct an effective risk management of inventory under the comprehensive risk management framework concern for many businesses, Taking a coal machine manufacturing company as an example, this paper made a thorough research on the assessment of inventory-related risk, the formulation of risk management strategy, inventory control methods and means of risk management mechanisms in order to provide for the relevant manufacturing enterprises on the theory and practice of reference.

This paper summarizes the developments and innovations of underground coal mining technology in China in recent years and discusses the underground coal mining development direction of China. To construct the large underground coal mine of high output and efficiency which featuring “intensive high-efficiency, intelligent security, ecological harmony and scientific development” in the new development stage will promote the structural readjustment of coal industry and industrial upgrading as well as elevate the level of sustainable development of coal industry in all respects. It also has strategic and realistic significance for ensuring the security of energy supply of China.

After the interpretation of the "Notice on Accelerating The Construction of Emergency Chamber for Coal Mine", understanding the development of the adoption of special drilling and dedicated line to refuge chamber, elaborating adjustments for refuge chamber construction way in the notice and analyzing the misunderstandings of the file, this paper points out whether the refuge chamber which adopting special drilling or dedicated line, doesn’t need to adopt devices of high-pressure oxygen bottles, toxic and harmful gas removal, or temperature and humidity adjusting device; it needs to be decided based on the conditions of mines. Besides, We need to distinguish the effect of the Notice on refuge chamber construction and its prospect in accordance with geographical location.

China is a country with abundant reserves of thick coal seam, based on this background, research to improve the special thick seam mining rate method. By using FLAC2D numerical simulation software to analyse the different coal pillar width internal stress and displacement distribution, analysis of Y direction of displacement and stress of knowledge with small coal pillars and width of coal pillar of roadway to protect basic agreement. In 1210 working face roadway with small coal pillar during 5m and 30m wide coal pillar to industrial test in site, and through the comparison of the different coal pillar width range electromagnetic radiation data and vibration spectrum prove that 5m small coal pillar can stable to roadway protection, as the special thick seam raise stoping rate provides a the new train of thought.

Contrary to universal override trip in coal mine power system, the paper analyzed the defects of the related protection principles and methods for avoiding override trip. On the basis of the current intelligent protector status and the existence construction conditions, a new technology of avoiding override trip based on GOOSE with selective short-circuit protection is provided. Compared with the original protector, the new protector adds GOOSE com-munication module, which shares an Ethernet with monitoring systems and can reliably transfer GOOSE blocking signal. The results of testing and operation shows that the Protector based on GOOSE can quickly and accurately find the fault point and select the nearest breaker to trip, it can efficiently avoid the large blackout caused by Override trip and improve the reliability and safety of the coal mine power system.

This paper presents briefly the pole adjustment scheme and measures when the 10kV overhead line of an east ventilation shaft strides over coal mining subsidence area，and some Suggestions are given in the last.

According to the principle of optimum selection equipment in production system of electric submersible pump in CBM Wells, the optimization design method of production system of electric submersible pump is determined, and the calculation steps of optimum selection equipment are presented. The results show that it can meet the production demand of electric submersible pump in CBM Wells by this method, and is important to improve the production system efficiency of electric submersible pump.

Abstract：It is discussed the design of the filling station with highly-concentration cemented filling method in Xinyang coal mine. After introducing the technology briefly, it is probed that the elements of a filling station, the principles and main steps of building a filling station. Based on the requirement of the filling system in Xinyang coal mine, choices of the types of the machines are made and two plans are put out which build the filling station near the east ventilating shaft or the NO.2 mine respectively. At last the east ventilating shaft was chose for the shorter transport distance, easier technology and better economic benefits.

Based on the characteristics and requirements of mine heating and refrigeration thermodynamics, the multi-function heat pump refrigeration unit is optimal designed, and two screw compressors used as refrigeration compressor of the multi-function unit are selected. The preferably switching working condition is achieved under the compression ratio change largely, which has a good load adjustment capability and adaptability. By the running test shows that the multi-function variable conditions refrigeration unit and its system can meet different functional requirements and achieve the design purpose.

A fuzzy control system for measuring the methane concentration based on FPGA.This paper researched fuzzy control algorithm and the establishment of fuzzy control rules in detail,it also realize the implementation of fuzzy control system based on FPGA.Compared with traditional control devices.This system has the advantages of high control acduracy and small hysteresis.

There is a hard overburden which 200m thick above coal seam of Xuandong coal mine. Through theoretical analysis and field measurement think hard overburden is the main source of power to underground dynamic disaster. The span length is increasing with the face advance, besides it gathers a large amount of elastic energy, then, leaving hidden danger for the mining. Last, combining the cause of underground dynamic disaster put forward the targeted methods to prevent the occurrence of rock burst and coal and gas burst.

Basing on the analysis of the rock burst occurred characteristics from Qianqiu Coal Mine, we research the influence of the rock burst formation on coal mine geological factors and mining technology factors. It is the rock burst forming geological factors and internal factor，that the coal seam has the bump proneness and the mining depth arrival the critical depth of rock burst frequency, increase rock burst hazard of horizontal tectonic stress , and there are thick hard rock exist in overlying strata. It is the mining technology factors and inducing factors of incident rock burst in the lower roadway, the lower roadway is located in the middle position of high stress island area formed by coal face skip-mining and the working face supporting strength than roadway.

According to the 14214 mechanized mining face actual mining production under the broken roof conditions, Combine the FLAC3D numerical calculation with theoretical analysis, Analysis the Instability Pattern of the roof of Mechanized mining head face. The studies have shown that roof of head face caving degree becomes smaller and stability enhances with the working resistance of support increases.The impact on the control of head face roof weakened with the increase of support’s working resistance when it reached more than 80% of the rated working resistance.The plastic failure area is located in the roof in front of coal wall and mainly with the form of compression and shear failure when support’s working resistance reached the rated working resistance.The front and rear pillar’s control area of roof is different if their’s working resistance ratio different.It should be raised the front pillar’s working resistance under broken roof conditions.It is conducive to the stability control of end face roof and the stability of the support when its ratio is 1:1.2.

Studied the top-coal movement and running of full-mechanized caving mining in which Pingshuo mining area,the simulation experiment on the rule of top-coal movement and running was done for the Pingshuo 4# , 9# coal ,obtained the relation of coal-gangue content and top coal drawing ratio in the different of mining and caving ratio,and the different exploitation method.The experimental data show that the reasonable exploitation method at Pingshuo mining area is one cut by one drawing. In the process of coal caving ,it can take 1/5 of gangue ratio among coal-gangue flow on drawing jaws as the criterion of ending drawing top coal.

Abstract: To study the characteristics on rock burst occurring from floor in deep underground engineering, four-body component was adopted to simulate coal and rock mass structure. This paper used Flac3D numerical simulation software to imitate component true triaxial compression test. And deep mining environment was simulated by different intermediate principal stress parameter and unloading path. In view of the tectonic stress and energy, the related characteristics of rock burst occurring from floor in deep mining were analyzed. The results indicated that, compared with unloading stress from middle principal stress direction, it was more advisable to unload stress from the smallest principal stress direction because it experienced for longer periods of time from unload stress to the rock burst happened. Then the time step which was from unloading stress to rock burst happened and intermediate principal stress parameter was exponential relationship. In addition, when unloading the smallest principal stress, the time step was exponential rising with the increasing in intermediate principal stress parameter, while the result was contrary to unloading the middle principal stress. And the rock mass that occurred rock burst was experienced processes as brittleness, ductility, brittleness and plasticity.

When single-phase ground fault occurs in the neutral indirectly grounded system, more than 80%of the associated ground arc fault is introduce. Fault Arc is random, and change with the change of the surroundings. Arc is discussed simply in the theoretical analysis, and focused on the arc simulation model. Arc grounding fault model which the live interference is considered, is built in the EMTP/ATP. The model breaks the traditional ideal model, provides data support for the fault line detection in neutral point non- effectively grounded-system, and lays a solid foundation for the follow-up study.

Detailed local mean decomposition (Local mean decomposition LMD) non-stationary signal processing methods, LMD algorithm with a high degree of self-adaptive, able to decompose the characteristic parameters of the data itself, it is able to arbitrarily a very complexnon-stationary signals into several PF (Product function, production function), and components with certain physical meaning emission coal Face Gas collected data LMD decomposition, multiple PF component. Then use the improved neural network method were predicted, then synthesis of different prediction results superimposed reconstructed and Gas Emission Prediction value. Actual monitoring data for the gas analysis can draw this method to predict the effect of higher prediction accuracy than the conventional neural network methods, LMD method decomposition PF component has a certain manner regularity, so more substantial increase the prediction accuracy of gas emission, the case study also shows that the predicted results with actual monitoring results extremely high consistency.

Sodium hexametaphosphate influence in flotation on dropping ash content and its impact on settling situation of flotation tailings are investigated in this paper by means of Zeta potential, IC (Ion Chromatography), flotation test, free settling experiment. The results show sodium hexametaphosphate added in flotation can drop the concentrate ash content and increase its yield. However, with an increase of sodium hexametaphosphate adding, water hardness of flotation tailing decreases ,surface electronegativity of ultrafine-mud particles enhances and sedimentation velocity of flotation tailings reduces.

The lignite is low metamorphic grade coal, but hard to use effectively, Drying is the key process to the effective utilization of lignite , It is necessary to study the influence factors of lignite drying performance. Effects of particle size, temperature, ash content and dense medium on drying efficiency of fine lignite in an infrared moisture meter are investigated by drying experiment, This was followed by the analysis of the drying results by utilizing effective moisture diffusivity. The results show that particle size and temperature have important influence on drying efficiency, with the decrease of particle size, the drying rate increases and the effective moisture diffusivity drops.The drying rate and the effective moisture diffusivity exhibit an increasing trend with increasing temperature. Both the lignite drying rate and the effective moisture diffusivity decrease with the decrease in ash content. Interfusing dense medium (magnetite powder and magnetic pearls) has significant influence on drying efficiency, the drying performance gets stronger on adding dense medium. Amongst all, the magnetic pearls work best during the process of drying, and it can achieve the best drying performance when the content of magnetic pearls reaches 50%.

The scientific norm quota of electricity consumption is an important method in saving energy and reducing cost for a company. The method of norm quota which only concerns coal mine cannot implement quota management responsibility system in the real meaning. This paper based on the activity-based costing theory, dividing different activities of coal mine, determining activity electricity consumption motivation and choosing basic methods of norm quota to formulate the electricity consumption quota of the operation of coal mine. The specific application of the method in one coal mine of Shenhua Ningxia Company has saved electric energy and made economy benefit.

High quality grade evaluation of coal resources provides the basis for the coal industry planning and the reasonable exploration and utilization of coal resources. Fully referring the predecessor's research achievements of coal quality evaluation, based on the coal quality data obtained by the coal geological exploration, the index system and the index division scheme of the coal resources high quality grade evaluation were established for coking coal, steam coal and chemical anthracite in Shanxi according to new current standards and specifications. Each index weight was determined using the combination methods of the distance maximization and the expert scoring. Based on the grey relation analysis, the dynamic mathematical models of the coal resources quality grade evaluation were established. Using the models, the high quality grade evaluation of coal resources was carried out for three exploration areas in Shanxi.

In this paper, the experimental results of pulling resistance of plant bar are given. The failure mode, ultimate load, anchorage slip, anchor group effect, stiffness and ductility of single bonded bars and group bonded bars in concrete subjected to tension have been investigated . The influence of group bars on the bond behavior has been discussed. The results show that the anchor group effect becomes increasingly obvious with the increase in the number of anchorage, and the anchorage initial slip is significantly reduced. The anchorage with the number of two or three has the best performance.

Abstract:To ensure the safety and efficient recovery of the lengthened in NanYang mine, the reasonable supporting strength the strata behavior regularity and the support parameter were studied and analyzed with a combination of field measurement theoretical analysis and numerical simulation methods when the working face extended to 180m from the 150m. The analysis showed that reasonable supporting strength shall not be less than 0.92MPa,the pressure peaks of abutment increased to 17MPa from 14.89MPa,the position extended to the front wall of 16m,the effects extended to 22~37m,the roadway near the gob should be strong support with high strength bolt and anchor.The research results has important guiding significance to NanYang mines and the similar condition mines.

The average thickness of 2515 working face which is belong to Heng Jian Coal Mine Han Dan Coal Mining Group is 4.5m, this part of the coal seam is under village buildings，In order to exploit this part of the coal seam, Heng Jian Coal Mine use the super high-water material filling mining method，and use the high-water material retaining roadway along goaf，this mining method has received great results.

Through fully-mechanized mining fast docking technique theory is analyzed, and combination of Guqiao coal mine, 1121 (1) the specific conditions of fully mechanized working face, and put forward the base line determination, stent azimuth control, elevation and conveyor slope control etc docking effective method. Further illustrates the butt the preparing work before, face butt and equipment docking process, summed up the feasible fully butt technology. Through the scraper conveyor butt joint spacing validation, and the results show that face a butt joint success, when using only 16 h. The technology in the implementation of Guqiao coal mine,not only technically feasible and economically reasonable ,effectively solve the mine irregular shape area mining technology problem, improve the recovery rate of resources. The mine mining, especially the exhaustion of resources type mine reserves potential has certain reference significance.

According to its dry drilling problem, a new drilling hole dust collection system was used by Longtan coal mine. The thesis introduced the components and property of the system. By practical application and technical investigation, the dust collection efficiency is more than 97%, so the difficulty of dry drilling has been resolved, the miners’ occupational health and the coal mine safety production are guaranteed.

The paer introduce the original slurry treatment system of the Antai coal preparation plant and existing problems, By analysis the size composition of the flotation feed , Proved the process optimization is necessary and reasonable. And proposing the optimization program to adjust the flotation feed composition and the flow direction of the filtrate. By comparing the results of the original process and optimized process and analyzing its economic benefits, Evaluation of its optimization results, The results showed the technology Optimization not only solved the problem that the flotation is poor and the concentrations of circulating water is high, but also Got better economic efficiency and environmental benefits

LN cooling system is a new technology which be studied and applied recently in coal mine, it has cooling air and extinguishing function, in order to solve the problem of Heijin coal mining working face in high temperature hot against, in the face with a LN cooling system, now given the introduction of system type、process and equipment selection, and list the attentive question for design and operation which were analyzed and discussed, running results show that the application of LN cooling system is feasible.

The Xin'an coalfield mines were threated seriously by the Ordovician limestone water and have occurred many water inrush accidents. Transient electromagnetic technology had been widely applied in bottom karst water detection, and received good results, this paper summarizes the new analysis features of transient electromagnetic applications in recent years: The severe abnormalities was the preferred area of drilling verification, then process mildly abnormal area by the governance effect of severe abnormalities; Syncline area is favorable water-rich section and have higher verification rate; To judge water inrush source, using transient electromagnetic detection results can achieve rapid and accurate identification.

According to the fracturing phenomenon for the crankshaft of mine flameproof diesel engine.As an example in a flameproof diesel engine crankshaft system in this paper, a dynamic simulation model consisting of multiple degrees of freedom of flexible body was established by the use of dynamic simulation software Excite, and analysed about a flexible body of crankshaft stress and the response of torsional vibration. The results show the torsional vibration peak appears torque point in the maximum about 1700r/min for the crankshaft, occur resonance phenomenon in here, causes the wring.Then through the experimental verification of the simulation results and experimental results is similar to, illustrated by simulation analysis is an effective method to solve, and explosion-proof diesel engine crankshaft fracture and provides the theoretical support.

According to the problems of incomplete kind and low reliability of protection of mine belt conveyor, the paper designed an intelligent protection system of belt conveyor based on C8051F020 and RS485 buses, analyzed common faults of belt conveyor, introduced hardware structure and software design of the system. Identified measuring methods of belt faults of speed, temperature, fog and disalignment. The protection system used host computer and slave computer two levels system to collect and process various signal parameter output by system’s sensor, which realized real-time speed detection and intelligent judge of belt conveyor faults, reduced malfunction rate.