Within the session the following papers are to be presented:

Martin Junker, RAG Mining Solutions GmbH, Herne, Germany, Marek Growiec, RAG Mining Solutions GmbH, Katowice, Poland

Planning of galleries for high performance longwall production in thin coal seams

ABSTRACT: Planning work, roadway development and excavation are the main intervals of the lifecycle for a roadway in longwall coal mining. The standard system of planning, which is offered by the German RAG Mining Solutions GmbH follows this phases and is focused on the geological and geotechnical preconditions, the stress distribution influenced by multiple seam working and a wide range of support elements and systems available. Continuous enhancements of monitoring and equipment within the past 25 years give the opportunity of development and use of the roadways with minimum technical risk. The following paper gives an overview to this lifecycle and the know-how of RAG Mining Solutions either for matters planning or of processing under the preconditions of a difficult deposit, a wide range of mine layout variations and various support systems.

Stanisław Prusek - Główny Instytut Górnictwa, Poland

Selected methods of forecasting gate roads deformation

ABSTRACT: This paper presents selected methods of forecasting gate roads deformation in countries where underground mining of hard coal takes place. Two of those methods, developed at the Central Mining Institute, have been presented in more detail. The methods are based on the results of the research on horizontal and vertical convergence in gate roads maintained behind the longwall face with roof caving. First method is based on empirical relationships determined by statistical methods. The second one relies on the modified Hoek’s Brown failure criterion and allows to predict the deformation of gate roads by means of numerical calculations with Phase software.

Janusz Chmielewski, Bolesław Kozek - Lubelski Węgiel Bogdanka S.A., Poland

Evolution of the Methods of Maintaining Longwall Galleries in the LW Bogdanka S.A. Mine

ABSTRACT: The article presents the current ways of managing and maintaining longwall galleries in the mine of Lubelski Węgiel Bogdanka. It discusses experiences related to the “towards field” mining system, which was used in 1982-1990, along with maintaining longwall galleries behind the wall. It describes the presently used mining system, “from field”, and the way of exploiting longwall galleries in that system. It presents types of the gallery support system used and its modifications which took place over years of mining activity, as well as ways to reinforce the support system for the purpose of maintaining the wall-gallery crossing. It discusses new conditions concerning longwall galleries for plough walls.

Andrzej Tor, Rafał Dobrzyński, inż. Kazimierz Koliński - Jastrzębska Spółka Węglowa S.A., Jastrzębie-Zdrój, Polska

Utrzymywanie wyrobisk przyścianowych w kopalniach JSW S.A.

ABSTRACT: Prowadzenie eksploatacji systemem ścianowym na zawał w warunkach dużej głębokości powoduje znaczne obciążenie wyrobisk górniczych. Stan ten potęguje się przy występowaniu trudnych warunków górniczo-geologicznych i często zachodzi konieczność  wykonywania każdorazowo dla nowej ściany nowych dwóch chodników przyścianowych.

Jednym z istotniejszych problemów w kopalniach podziemnych z punktu widzenia praktyki górniczej jest utrzymanie chodników przyścianowych za frontem ściany.

Każde wyrobisko górnicze na skutek wybrania masywu skalnego powoduje zmianę pierwotnego stanu równowagi charakteryzującą się wzmożonym ruchem skał do wyrobiska wywierającym nacisk na obudowę. Występujące wówczas wzmożone obciążenia wzrastają przy prowadzeniu eksploatacji górniczej, która powoduje niszczenie skał i powstawanie dodatkowo ciśnień deformacyjnych. Wzmożone ciśnienia pionowe przenoszą się na ociosy chodnika, powodując zaciskanie wyrobiska oraz wypiętrzanie skał spągowych. Powstające zjawisko wypiętrzania skał spągowych do wyrobisk chodnikowych stanowi poważne utrudnienie w utrzymaniu tych wyrobisk i zapewnieniu ich funkcjonalności pod względem transportowym i wentylacyjnym oraz prowadzi W artykule poruszono problem stateczności wyrobisk przyścianowych za frontem ściany oraz celowość ich utrzymywania. Następnie przedstawiono przykładowe metody utrzymywania wyrobisk za frontem ściany w kopalniach JSW S.A. w zależności od panujących warunków geologiczno – górniczych oraz przeznaczenia wyrobiska. do licznych komplikacji i utrudnień w ruchu kopalni.

Stanisław Prusek, Marek Rotkegel - Główny Instytut Górnictwa, Katowice, Poland

Modern methods of designing supports of excavations for plow longwalls

ABSTRACT: Effective extraction of hard coal with the use of plow technique results in the fact that many issues within mine technologies need to be solved. One of the most important is performing a proper design of the support of excavations and its reinforcement. Generally, it means that the support may be adjusted to secure the T-junction so that the extraction process is effective and safe. In this paper the most important phases of designing the support of dog headings, by use of the method invented in the GIG, have been described. There are also examples of the supports of plow longwall gateroads, lately driven in mines “Zofiowka” and “Bogdanka”.

Mirosław Masiakiewicz - LW “Bogdanka”, Puchaczów, A. Szyszka - “SIGMA” S.A., Barak, Poland

The practicalities of optimizing automated longwall plough systems under the conditions prevailing at the LW Bogdanka S.A. mine - special longwall cavity lining and output self-loading system at the longwall-heading crossing

ABSTRACT: The decision to mine thin coal seams was a natural outcome of the rational and balanced approach the LW “Bogdanka” S.A. mine has adopted towards exploiting coal deposits. These resolutions resulted in deploying the first automated plough longwall (manufactured by Bucyrus International). The plough had previously worked the “Nadrybie” field. After observing the system in operation and gaining experience with the selected technology, a team of experts from the LW “Bogdanka” S.A. coal mine, along with representatives of “SIGMA” S.A. and “HAJDUK Group” Sp. z o.o., was set up to find ways of optimising the automated plough longwall. The result is a highly innovative solution, viz. a Special Longwall Cavity Lining and an Output Self-Loading System.

Krzysztof Krauze, Łukasz Bołoz, Tomasz Wydro, Poland

Prototype of temporary mechanized  mine roadway support of the dog headings

ABSTRACT: Technology of the dog heading driving with use of roadheaders or explosive material has been described In the present study. Difficulties occurring during dog heading driving, particularly those related with the support installing, have been presented. Constructional solutions of different mechanized mine roadway supports, including their advantages and disadvantages, have been presented.  Based on the executed analysis of the mine dog heading driving, including construction of mechanized roadway supports, a new concept of temporary mechanized roadway support has been developed and its technical parameters have been cited.

Waldemar Korzeniowski, Łukasz Herezy, Krzysztof Skrzypkowski - AGH University of Science and Technology, Cracow, Poland

Tail gatedeformation characteristic during plow exploitation of the 1/VI longwall face in 385/2 seam in LW “Bogdanka” mine

ABSTRACT: The article presents the results of dislocations and deformations measurements of the tail gate obtained during the first plow complex exploitation in Lublin Coal “Bogdanka” mine. Together with the advance of the longwall face the tail gate was maintained for use in future exploitation. For particular types of roof support and rockmass reinforcement methods (cribs, rod bolts and string bolts) the values of heading convergence, fracture zone reach and fissures have been defined, indicating the rock mass strengthening effect depending on the chosen technical solution.

Heinz Dwuletzki, Burkhard Pfaender – CARL BECHEM GMBH, HAGEN Germany, Karel Niemczyk, LUBRICANT s.r.o. Czech Republic

New Fire-resistant Hydraulic Fluids Type HFA for Mining Use – Critical Analysis.

ABSTRACT: Fire-resistant hydraulic fluids of type HFA form a very important subgroup within the hydraulic fluids H.  Both water mixable species are used for underground mining; type HFA-S (solutions) and type HFA-E (emulsions) are discussed in detail. Test procedures according to various requirements need to be fulfilled: The 7th Luxemburg report (1994) describes most of the tests followed by the requirements of OE-Manufacturers and end users. Ecological properties and technical requirements are discussed and compared with the chemical formulation of different species of HFA-fluids.

Marek Płonka, Sylwester Rajwa - Główny Instytut Górnictwa, Katowice, Poland

Assessment of powered support loadings in plow and shearer longwalls in regard to the pressure measurements in props

ABSTRACT: The results of static pressure measurements in the space under props pistons of powered support, performed  during mining of seams in five longwalls with roof caving were presented. Measuring systems, and methods of data collection and storage were characterized. The results of measurements were presented in the form of plots of pressure variations and the support load-bearing capacity. Sample of statistical analysis of the recorded data were presented.

Dr inż. Zbigniew Rak, Dr inż. Jerzy Stasica - AGH University of Science and Technology, Krakow, Poland

Maintaining of the tail gate behind the exploitation face in difficult geological and mining conditions in LW „Bogdanka” mine

ABSTRACT: The increasing costs of driving longwall headings result in systematic research concerning their maintenance behind the exploitation face in Polish coal mines. This paper describes the results of such attempts which were undertaken in relatively difficult conditions in LW “Bogdanka” mine in the 80s. of 20th century and - after a long break – in 2010. The article gives detailed description of the technology designed to protect the tail gate 1/VI in the seam 385/2 maintained behind the exploitation face in the conditions of LW “Bogdanka” mine. The method of securing the tail gate from the beginning of its drive until the last reinforcements built-in behind the longwall face. Previous results of the attempts to maintain the heading in one-sided surrounding of gobs were also described.

Piotr Głuch - Politechnika Śląska

Projektowanie obudowy kotwowej dla utrzymania chodników przyścianowych ścian strugowych 

STRESZCZENIE: W artykule omówiono projektowanie obudowy kotwowej dla utrzymania chodników przyścianowych ścian strugowych uwzględniając trudne warunki geologiczno – górnicze, dużą głębokość eksploatacji, duży wybieg ściany i konieczność zapewnienia dużego przekroju wyrobiska. W projektowanych rozwiązaniach obudowy kotwowej zwrócono uwagę na stosowanie kutwienia z wysokim naciągiem wstępnym, a systemu obudowy podporowej z wysoką podpornością wstępną. Utrzymywanie chodnika za frontem ściany w warunkach kopalni „Bogdanka” zaproponowano dla wykorzystania go do lokowania kamienia i dla celów wentylacyjnych ściany strugowej oraz drążenia nowego chodnika wtórnego dla drugiej (kolejnej) ściany. Samodzielną obudowę kotwową można wykonywać w przecinkach ścianowych, likwidacyjnych oraz technologicznych.

Mirosław Masiakiewicz - Lubelski Węgiel „Bogdanka” S.A.

Prospects of using the MR 620 roadheader with advanced mechanical bolting system in the Bogdanka mine

ABSTRACT: The article presents a new unique solution for the system for driving roadways developed for the conditions existing in the mine of Lubelski Węgiel “Bogdanka” S.A. The purpose of the presented organisation and technical project is to increase the progress rate of driving roadways within arch-shaped bolt support. The system will comprise a high power roadheader, a mechanized platform for installing gallery support frames, and a double boom bolting machine. The new face system will enable simultaneous performance of certain basic operations of the engineering cycle, such as mining and bolting, which will bring a significant increase of the driving progress rate. The system involves building a support system in the face to ensure fast support of the rock mass by means of mechanical lining, using containers filled with a fast-setting binding material under pressure, and bolting, in order to reinforce the rock mass behind the roadheader.

Andrzej Jagiełło, Paweł Nowak - Sandvik Mining and Construction Sp. z o.o. w Tychach

MR620 Roadheader offers opportunity for improvement of drift driving efficiency

ABSTRACT: This paper presents a roadheader of 600 series suitable for mining of rocks of UCS of up-to 140 MPa. In addition, optional equipment for the roadheader, in particular bolting equipment, is discussed. Impact of changes in technology of gangway driving on daily advance rate is discussed on the basis of simulations.

Marek Czechowski - KGHM Polish Copper, „Lubin” Mine

„Lubin” mine experiences in driving heading excavations with Sandvik Mining and Construction’s MH-620 heading machine

ABSTRACT: The experiences gained during the drive of heading excavations with Sandvik’s MH-620 in two entirely different areas of “Lubin” mine are shown in the article. The influence of imperfect construction of the machine on the heading drive process has also been highlighted.

Krzysztof Kwiatkowski - Lubelski Węgiel „Bogdanka” S.A.

Wykonywanie i utrzymywanie chodników przyścianowych dla ścian strugowych w kopani Lubelski Węgiel „Bogdanka” S.A.