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Evaluation of Longwall Face Support Hydraulic Supply Systems Graduate Theses, Dissertations, and Problem Reports 2007 Evaluation of longwall face support hydraulic supply systems Ted M. Klemetti II West Virginia University Follow this and additional works at: https://researchrepository.wvu.edu/etd Recommended Citation Klemetti, Ted M. II, "Evaluation of longwall face support hydraulic supply systems" (2007). Graduate Theses, Dissertations, and Problem Reports. 4312. https://researchrepository.wvu.edu/etd/4312 This Thesis is protected by copyright and/or related rights. It has been brought to you by the The Research Repository @ WVU with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you must obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in WVU Graduate Theses, Dissertations, and Problem Reports collection by an authorized administrator of The Research Repository @ WVU. For more information, please contact [email protected]. Evaluation of Longwall Face Support Hydraulic Supply Systems Ted M. Klemetti II Thesis Submitted to the College of Engineering and Mineral Resources at West Virginia University in partial fulfillment of the requirements for the degree of Master of Science in Mining Engineering Syd S. Peng, Ph.D., Chair Keith A. Heasley, Ph.D. Yi Luo, Ph.D. Thomas Barczak, Ph.D. Department of Mining Engineering Morgantown, WV 2007 Keywords: Longwall Mining, Shields, Supports, Hydraulic Supply System, Setting Pressure Copyright 2007 Ted M. Klemetti II ABSTRACT Evaluation of Longwall Face Support Hydraulic Supply Systems Ted M Klemetti II With increases in panel size and production levels in longwall mining, the hydraulic flow rates required to allow the shields to keep pace with the mining operations have substantially increased. The panel size and production increases have also increased the hydraulic supply system’s pressure losses. To quantitatively evaluate the possible design changes to the hydraulic supply system, a practical and accurate method of evaluating potential hydraulic supply systems for the shields is needed. This thesis endeavors to develop a method to evaluate the effects on pressure and flow rate from changes in a hydraulic supply system and to determine the necessary design specifications of the system to supply a specific flow at a specific pressure at a particular mine site. An initial model was developed and shows great promise; however, additional field and laboratory testing are needed to calibrate the model for use in the design of hydraulic supply systems. ACKNOWLEDGMENTS I would like to extend sincere thanks to my committee chair, Dr. Syd Peng, for his guidance and understanding during the hours he devoted to helping me complete this thesis. I would also like to thank the other members of my committee, Dr. Keith Heasley, Dr. Li Yuo, and Dr. Thomas Barczak for their wisdom, advice, assistance, and support. I would also like to thank the folks from DBT and Foundation Coal for their assistance and time. Specifically, Dan Lincoski, Peter Zhang, Jack Trackemas from Foundation Coal for their support and guidance. I am grateful to the many people who supported and encouraged me during the completion of this thesis. First, I would like to thank my family and friends who have given me moral support and encouragement throughout my graduate studies. I am indebted to my mother, Elyce Biddle, for teaching me that with hard work and determination I can accomplish the goals that I have sought. Without the help of all these folks, this thesis would not have been possible. iii TABLE OF CONTENTS Page Abstract .......................................................................................................................... ii Acknowledgements ........................................................................................................iii Table of Contents.......................................................................................................... iv List of Figures................................................................................................................ vi List of Tables..................................................................................................................x Abbreviations ...............................................................................................................xiii CHAPTER 1 – INTRODUCTION.................................................................................... 1 1.1 Problem Statement............................................................................................. 1 1.2 Research Objectives .......................................................................................... 3 1.3 Thesis Overview................................................................................................. 4 CHAPTER 2 - THEORY AND LITERATURE REVIEW.................................................. 6 2.1 Longwall Mining Description & Terminology ...................................................... 6 2.2 Longwall Face Support Systems...................................................................... 10 2.3 Importance of Proper Setting Pressure and Flow Rate.................................... 19 2.4 Hydraulic System Description & Terminology ............................................... 23 2.5 Fluid Mechanics of Hydraulic Supply Systems................................................. 32 2.6 Previous Works in Hydraulic Supply Systems.................................................. 43 CHAPTER 3 – FIELD STUDY...................................................................................... 46 3.1 Information Required from Mine Site................................................................ 46 3.2 Field Site Hydraulic System and Operating Procedures .................................. 48 3.3 Location and Description of Instrumentation.................................................... 54 3.4 Data Collection Plan......................................................................................... 56 3.5 Data Analysis ................................................................................................... 58 3.6 Field Study Results .......................................................................................... 61 CHAPTER 4 – SOFTWARE......................................................................................... 78 4.1 Critical Evaluation of Software ......................................................................... 78 4.2 FluidFlow Software Description........................................................................ 79 CHAPTER 5 – MODEL DEVELOPMENT .................................................................... 87 5.1 Initial Model Development ................................................................................ 87 5.1.1 Initial Inputs from Previous Research...................................................... 87 5.1.2 Initial Model Design ................................................................................. 89 iv 5.1.3 Initial Model Analysis............................................................................... 96 Sensitivity Analysis.................................................................................. 97 Scenario Analysis.................................................................................... 99 5.2 Model Calibration ........................................................................................... 100 CHAPTER 6 – RESULTS OF MODEL DEVELOPMENT........................................... 102 6.1 Results of Initial Model Development ............................................................. 102 6.1.1 Results of Initial Input Determination..................................................... 102 6.1.2 Results of Initial Model Design .............................................................. 106 6.1.3 Results of Initial Model Analysis............................................................ 107 Sensitivity Analysis................................................................................ 108 Scenario Analysis.................................................................................. 115 6.2 Results of Model Calibration .......................................................................... 116 CHAPTER 7 - CONCLUSIONS.................................................................................. 121 7.1 Discussion...................................................................................................... 121 7.1.1 Initial Model Design ............................................................................... 121 7.1.2 Field Study............................................................................................ 121 7.1.3 Model Calibration.................................................................................. 123 7.2 Limitations of the Study.................................................................................. 124 7.3 Future Research and Model Enhancements.................................................. 126 BIBLIOGRAPHY......................................................................................................... 129 APPENDIX A: Distributions of Field Study Results.................................................... 133 APPENDIX B: Field
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