A waterjet mining machine for use in room and pillar mining operations

The importance of production planning for improving the performance indicators of a mining enterprise is indicated. The possibility of simulation modeling using for this aim is shown. It is shown that the created model has a large number of stochastic parameters. It is investigated that there is a problem of research lack about the choice influence of the mining modeling results with different statistical distributions. It is known that with an increase in stochastic deviations from the initial parameters, the productivity of queuing systems decreases. Purpose of work is to study this influence with four statistical distributions of a random quantity (uniform, normal, negative bi-nomial and Poisson distribution) for individual operations and their combinations. In addition, it is necessary to determine how much a change in one particular parameter will affect the overall result of the modeling. Materials and methods. In the previously created simulation model, a stochastic delay is added to the time of individual operations. The addition of such a delay with different sta-tistical distributions and with the same mathematical expectation is investigated. The simulation re-sults are compared with each other, for each individual operation the absolute and relative devia-tion of the results is shown. Further, a similar simulation is performed when all the simultaneously selected parameters changing. Result. It is shown that the magnitude of the deviation significantly differs among all deviations. It is shown that for various single changes in operations, the largest and smal-lest deviations can be given by different statistical distributions. To study the joint change with all parameters, 3 modeling scenarios are implemented: all uniform distributions (this case is used now), the scenario with the smallest deviation and the scenario with the largest deviation. It is shown that switching to another scenario leads to a significant change in the simulation. Conclusion. It is con-cluded that the used significant influence of statistical distributions choice to the accuracy of model-ing the operation of the mining machine is shown, especially when they are taken into account to-gether. The results can be used to clarify the influence of individual factors in the simulation model and improve the planning of potash mining operations, for individual mining machines too.

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Ground pressure and overlying strata structure for a repeated mining face of residual coal after room and pillar mining

International Journal of Mining Science and Technology ◽

10.1016/j.ijmst.2016.05.017 ◽

2016 ◽

Vol 26 (4) ◽

pp. 645-652 ◽

Cited By ~ 13

Author(s):

Bangyou Jiang ◽

Lianguo Wang ◽

Yinlong Lu ◽

Xiaokang Sun ◽

Gan Jin

Keyword(s):

Room And Pillar Mining ◽

Ground Pressure ◽

Pillar Mining ◽

Mining Face ◽

Residual Coal ◽

Overlying Strata

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EFFECTS ON THE FINAL INTENSITY OF INPUT FORCES IN LONGBOLTS INSTALLED AT THE MINING OPERATION 2 AREA, OKD, INC.

Acta Polytechnica ◽

10.14311/ap.2018.58.0279 ◽

2018 ◽

Vol 58 (5) ◽

pp. 279

Author(s):

Pavel Dvořák ◽

Eva Jiránková

Keyword(s):

Life Time ◽

Mining Operation ◽

Short Term ◽

Room And Pillar Mining ◽

Time Period ◽

Pillar Mining ◽

The Subject ◽

Arch Support ◽

Cable Bolt ◽

Load Behavior

In the deep coal mines of OKD, Inc., both bolts and long bolts of different designs are used for the rock massif and steel arch support reinforcement. Continuous measurement of forces in 6 strand bolts and 1 cable bolt (long bolts, generally) was carried out during the trial operation of the modified Room and pillar mining method at Mining operation 2, site North, OKD, Inc. Hydraulic dynamometers were installed on these long bolts and a monitoring of forces took place throughout the life-time period of the mining panel No. V. From this measurement, a knowledge of their different load behavior with respect to the input stress parameters was obtained. The input intensity of the force applied to the bolting elements is burdened by losses of various kinds. The subject of the article is a description and analysis of the intensity of the initial stressing force applied to individual long bolts (with a threaded clamping bush or wedge barrel) and quantization of short-term stress losses with a description and analysis of these.

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