scholarly journals To improve the contact adaptability of mechanical roof support

2021 ◽  
Vol 266 ◽  
pp. 03015
Author(s):  
N. Babyr ◽  
K. Babyr
Keyword(s):  
Technical Solution ◽  
Support Section ◽  
Mechanized Support ◽  
Geological Conditions ◽  
Roof Support

The article proposes a constructive technical solution to increase the contact adaptivity of the mechanical roof support. The developed solution of the mechanized support section is able to adapt to changing mining and geological conditions in the process of excavation of the mining pillar, which increases the efficiency and safety of coal excavation in the longwall.

scholarly journals Tests of Geometry of the Powered Roof Support Section

Energies ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3945 ◽  
Author(s):  
Dawid Szurgacz ◽  
Jarosław Brodny
Keyword(s):  
Research Area ◽  
Measuring System ◽  
Analytical Models ◽  
Geometrical Parameters ◽  
Support Section ◽  
New Approach ◽  
Operation Process ◽  
Geological Conditions ◽  
Actual Geometry ◽  
Roof Support

A powered roof support is a basic protection mean for longwall excavations in which highly efficient mining is carried out. The support operates properly when its individual sections are spragged correctly in a working and their operating parameters meet specific requirements. The geometry of the section, and in particular, the correct position of the floor base and the canopy, have a significant impact on the parameters and effectiveness of its work. Disturbances in this area, in many cases, are the cause of damage and improper operation of the support. Therefore, a new method of testing the position of the section in a longwall was developed based on an analysis of its geometry. The basis of this method are inclinometers (angle sensors) mounted on the main structural elements of the section. Recorded values of the angles of inclination of these elements and the developed analytical models are used to determine the positioning of the section in a longwall. The main purpose of the research was to develop a method that would allow, in the simplest possible way, the analysis of section geometry in real conditions. A simplified analytical model was used to determine the actual geometry of the section. It was used then as a basis of an analysis of possible states of the position of the section in the mining wall, including the surrounding rock mass. The results were applied during tests of the section carried out in a testing station and in real (underground) conditions. The developed measuring system helped to determine selected geometrical parameters of the section during these tests. The purpose of the research was to verify the developed model and demonstrate that the geometry of the section has a significant impact on its uneven loading. The obtained results, especially from underground tests, confirmed that during operation the support sections are twisted, which may cause overloading of their construction and disturbance of the operation process. The developed method of testing the geometry of the section is a new approach to analyzing the work of the powered roof support operating in variable mining and geological conditions. The developed method of testing the position of the section based on the angle of inclination of its individual elements is undoubtedly a new approach to this research area. The results obtained should be successfully used in practice to optimize the support section and when selecting support for specific working conditions.

Minimization of Negative Impact of Well Cementing on Productive Horizons by Utilization of Swellable Packers

2021 ◽  
Author(s):  
Mykhaylo Paduchak ◽  
Viktor Dudzych ◽  
Anatolii Boiko
Keyword(s):  
Negative Impact ◽  
Differential Pressure ◽  
High Rate ◽  
Donets Basin ◽  
Technical Solution ◽  
Negative Consequences ◽  
Well Completion ◽  
Stable Production ◽  
Geological Conditions ◽  
Gas Tight

Abstract Avoiding of negative impact of slurry contact with productive sections by utilization of swellable pakers well completion systems as a key solution for depleted reservoirs. Results are compared to previously used classic well completion method with production casing cementing The new method of the well completion is based on a long period and many wells operations within Svyrydivske field in Dnipro-Donets Basin (here and after DDB). Precise selection of hybrid, oil and water based elastomers and correct placement in the appropriate hole zones for water and sectional isolation together with oil based mud utilization during drilling have provided stable production in depleted reservoirs and have minimized negative consequences from water filtration. The results achieved and the well completion method are described in detail to allow readers to replicate all results in a comparable geological conditions in DDB. Current well completion method has a couple of outstanding results achieved: –well integrity barrier is based on sufficient differential pressure provided by swellable packers;–reliable long term water isolation of all detected water contained intervals;–the production sections are not polluted by slurry filtrated water;–increased production rate comparing to cemented wells;–no risks of slurry loss during well cementing. This technology has been successfully implemented in both vertical and deviated wells on 4.5″ (114.3 mm) casing OD, in the interval 5100-5450 meters, bottom hole temperature 120-135°C. The differential pressure provided by swellable packer is up to 10,000 PSI (68.9 MPa). Fluid reactive packers are ready to expand and isolate highly cavernous hole sections and keep differential pressure sustainably. To achieve the best results with this well completion method, it is also important to use reliable gas tight casing connections and know precise reservoir characteristics. That is why the technology is recommended to be customized for well known brownfield reservoirs with high rate of depletion. The main benefit of the well completion method is a proved and safe technical solution for mainly depleted deep gas and condensate deposits in DDB (Ukraine) with sensitive economics

scholarly journals Analysis of rock mass dynamic impact influence on the operation of a powered roof support control system

2018 ◽  
Vol 29 ◽  
pp. 00006 ◽  
Author(s):  
Dawid Szurgacz ◽  
Jaroław Brodny
Keyword(s):  
Rock Mass ◽  
Real Life ◽  
High Energy ◽  
Hard Coal ◽  
Underground Excavation ◽  
Dynamic Impact ◽  
Support Unit ◽  
Geological Conditions ◽  
Innovative Solutions ◽  
Roof Support

A powered roof support is a machine responsible for protection of an underground excavation against deformation generated by rock mass. In the case of dynamic impact of rock mass, the proper level of protection is hard to achieve. Therefore, the units of the roof support and its components are subject to detailed tests aimed at acquiring greater reliability, efficiency and efficacy. In the course of such test, however, it is not always possible to foresee values of load that may occur in actual conditions. The article presents a case of a dynamic load impacting the powered roof support during a high-energy tremor in an underground hard coal mine. The authors discuss the method for selecting powered roof support units proper for specific forecasted load conditions. The method takes into account the construction of the support and mining and geological conditions of an excavation. Moreover, the paper includes tests carried out on hydraulic legs and yield valves which were responsible for additional yielding of the support. Real loads impacting the support unit during tremors are analysed. The results indicated that the real registered values of the load were significantly greater than the forecasted values. The analysis results of roof support operation during dynamic impact generated by the rock mass (real life conditions) prompted the authors to develop a set of recommendations for manufacturers and users of powered roof supports. These include, inter alia, the need for innovative solutions for testing hydraulic section systems.

scholarly journals Case Analysis of Damages to Control Hydraulics of the Leg in the Powered Roof Support Section

2019 ◽  
Vol 105 ◽  
pp. 03013
Author(s):  
Janina Świątek ◽  
Kazimierz Stoiński
Keyword(s):  
Coal Mining ◽  
Case Analysis ◽  
Hard Coal ◽  
Support Section ◽  
Full Extension ◽  
Safety Measures ◽  
Bench Tests ◽  
Hard Coal Mining ◽  
Roof Support

The article discusses a case of security hazard in a longwall equipped with a properly selected chock shield support with two legs, technically efficient, introduced to the market and for operation in compliance with the requirements covering Polish hard coal mining. As a cause of the hazard an accidental coincidence was indicated, such as the occurrence of a tremor at an area with unfavourable geometry for the operation of the support section and leg (including the shift of the double-telescopic leg from the 1st to the 2nd hydraulic stage) at the time of the mining process. Immediate safety measures were applied successfully. They were aimed at minimizing the conditions dangerous to the crew. The section was withdrawn and spragged again. As a result, the leg operated in full extension mode of the 1st hydraulic stage, obtaining the required strength and geometry of the section and leg. The presented case study will be additionally supplemented in the future with selected analytical and bench tests.

scholarly journals Tests of an Innovative Controller Designed to Control the Powered Roof Support

2018 ◽  
Vol 1 (1) ◽  
pp. 223-231 ◽  
Author(s):  
Dawid Szurgacz ◽  
Horst Gondek
Keyword(s):  
Control System ◽  
High Efficiency ◽  
Response Times ◽  
Support Section ◽  
Control Block ◽  
Basic Part ◽  
Control Functions ◽  
Basic Functions ◽  
The Moment ◽  
Roof Support

Abstract The article presents the methodology and results of tests of a prototype controller designed for the electrohydraulic control system of a powered roof support. This controller is the basic part of the developed, innovative control system. The tests were carried out on a custom-designed testing station, equipped with one section of a roof support. The aim of the research was to check the functionality and speed of the controller's response while working with the actual support section. The tested controller and the control system has a modular structure, which greatly facilitates its operation and use. Measurements of control functions were carried out on the controller connected to the electrohydraulic control block. The research mainly focused on determining the period starting from the moment of providing the signal to the moment of switching on the basic functions performed by the support section. The obtained results confirm the assumptions made. The controller's operation is very stable, and its response times are very short. It can therefore be assumed that the tested controller is correctly designed and constructed. This creates great possibilities for its practical application in the built-in system for controlling the roof support. This may be particularly important in the case of high-efficiency longwall complexes, for which wireless control of the support is planned to be used. The presented research methodology and obtained results should therefore be an important source of information in the field of testing controllers for powered roof supports.

Large Cross Section of Very Loose Gravel Layer Inclined Construction Support Technology Research

2012 ◽  
Vol 170-173 ◽  
pp. 3181-3185
Author(s):  
De Jun Meng ◽  
Dong Ming Guo ◽  
Xiao Li ◽  
Yan Bing Wang ◽  
Hua Jun Xue
Keyword(s):  
Mining Area ◽  
Mine Safety ◽  
Construction Technology ◽  
Technical Problems ◽  
Geological Conditions ◽  
Temporary Support ◽  
Efficient Construction ◽  
Personnel Safety ◽  
Mining Face ◽  
Roof Support

Very soft layer of gravel geological conditions in the mine construction has a serious impact on the efficient construction of the mine safety and personnel safety. Because the mining area where has no big development experience of the construction, the construction and development of mining face many difficult technical problems. For this passage we did some research by super support ,temporary support and permanent support technology for this problem, Ahead of the pipe roof support, U- shaped steel and backplane as the temporary support and reinforced concrete support as the permanent support of the roadway, the roadway can be passed the layer of the gravel easily. The construction technology can provide reference for the safe and efficient construction of the similar geological conditions.

scholarly journals Adapting the Powered Roof Support to Diverse Mining and Geological Conditions

Energies ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 405 ◽  
Author(s):  
Dawid Szurgacz ◽  
Jarosław Brodny
Keyword(s):  
Impact Load ◽  
Mining Industry ◽  
Operating Conditions ◽  
Service Workers ◽  
Basic Task ◽  
Geological Conditions ◽  
Control System Model ◽  
And Control ◽  
Design And Testing ◽  
Roof Support

A powered roof support is one of the most important machines of a longwall system. Its basic task is to ensure the safety and continuity of the mining process. The conditions of coal mining process are constantly changing and have significantly deteriorated in recent years, which in turn has also resulted in a significant increase in the requirements for mining support. As a result, it is necessary to develop an appropriate methodology that will facilitate the design and testing process of a power roof support as well as will help to select a roof support adjusted to given conditions. The article presents such a methodology. It is based on forecasted load impacting on a roof support, tests covering selected systems and elements of the section as well as legal conditions regarding the admission of the roof support to operation. This idea was developed in the form of a procedure that, by combining the three areas, should support the decision-making process in the case of different underground conditions. In terms of the expected load impacting on the support, the research team identified the most dangerous phenomena occurring in the rock mass that can generate these loads. Stand tests included impact load and permanent clamping of an excavation. The element that significantly impacts the safety of the support operation is a hydraulic leg, and therefore it was tested together with the safety system and the control system. Model tests were also carried out for the system with a safety valve. The developed concept takes into account legal conditions, which should include test results and different support operating conditions in a more flexible way. The main purpose of the work was to develop a comprehensive methodology for testing and assessing the possibility of using a powered roof support for given mining and geological conditions based on an analysis of safety and control systems. The presented approach is undoubtedly new and original, and can be widely used. It enables better adaptation of the support to given conditions. It also fits the research and activities designed to minimize the presence of miners or service workers in hazardous underground exploitation zones and to improve efficiency and boost sustainable development of the mining industry.

scholarly journals Impact of geometry of the powered roof support section on the rock mass

2018 ◽  
Vol 71 ◽  
pp. 00001 ◽  
Author(s):  
Dawid Szurgacz
Keyword(s):  
Rock Mass ◽  
Underground Excavation ◽  
Support Section ◽  
Correct Operation ◽  
Mechanical Elements ◽  
Roof Support

The required functions of the powered roof support, the functions it must fulfil and the mechanical elements cause that the support practically continuously works with the rock mass. This applies to the canopy, the floor base and the shield support. Due to the different susceptibility and strength of the rocks, the roof support may lose its stability. This condition results in an uneven section load and difficulties with moving forward the support in the underground excavation. This, in turn, can lead to disturbances in the operation of the entire longwall system. In order to avoid this situation, it is necessary to conduct geometry tests, e.g. section tests for a dedicated testing station using innovative measuring inclinometers. They indicate the importance of proper geometry for proper and correct operation of the support section. The research was carried out with the use of a new methodology designed to test the geometry of powered roof supports. The solutions were developed by the author of the article.

scholarly journals Enhancement of rock bolt performance through “active” ground control

2021 ◽  
pp. 27-30
Author(s):  
E. A. Razumov ◽  
◽  
S. I. Kalinin ◽  
V. G. Venger ◽  
E. Yu. Pudov ◽  
...  
Keyword(s):  
Rock Mass ◽  
Rock Fracture ◽  
Ground Control ◽  
Structural Components ◽  
Rock Bolts ◽  
Mining Depth ◽  
Rock Bolting ◽  
Geological Conditions ◽  
Roof Rocks ◽  
Roof Support

The research has proved that rock mass stability can be ensured using steel resin rock bolting including rods, fast-setting resin capsules, bearing plates, strapping and tension nuts. Interaction of these structural components with roof rocks and sidewalls involves obligatory displacement of rocks. The article presents the studies into applicability of steel resin rock bolting in difficult geological conditions in coal mines in Kuzbass. The steel resin rock bolting is considered in this case as the method of ‘active’ ground control. The ‘active’ ground control consists in the capacity of steel resin rock bolts to alter main strength characteristics of rocks, to increase their resistance and stability, and, thereby, to ensure efficiency of roof support. It is found that horizontal and vertical stresses in underground excavations depend on the mining depth. It is proved that rock bolts installed in the roof rocks can prevent or confine rock fracture.

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