Abstract
In a surface coal mine, efficient usage of shovels and dumpers should be most reliable and available to reach their production target. Keeping this in mind, this study was carried out at a surface coal mine, which is located at Open Cast-I, The SCCL, Kothagudem area, Telangana. The mechanical failure data such as time between failures (TBF) and time to repair (TTR) of each sub-system of a shovel-dumper system were collected and analysed statistically and graphically for reliability and availability. Graphical methods such as trend test and series correlation test and Chi-squared test were used to validate the independent, identically distribution of mean time between failures and mean and time to repair for the same a shovel and dumpers. Statistically, the Weibull distribution is selected as it was found the best-fit distribution by the Kolmogorov-Smirnov (K-S) test using Isograph Reliability Workbench. In K-S test, it was found that shovel KS1 has reliability of 0.2682 and dumpers BD1, BD2, KD2 and KD4 had reliability of 0.3731, 0.2850, 0.2897 and 0.2962, respectively for the 1 year of working hours. Also, calculated reliability- based time interval for preventive maintenance to achieve 70, 80 and 90%, respectively of reliability for same shovel-dumper system.
Acknowledgements
The authors wish to thank the Director General (HRD), Department of Human Resources/Employee Relations, the SCCL, Kothagudem, Telangana, for giving the permission to collect necessary data and publish this work.
Disclosure statement
No potential conflict of interest was reported by the author(s).
Additional information
Notes on contributors
N. S. Harish Kumar
N. S. Harish Kumar is pursuing his Ph. D degree in Department of Mining Engineering, National Institute of Technology Karnataka (NITK), Surathkal, India. He obtained his B. E (Mechanical Engineering) and M. Tech (Machine Design) from Visvesvaraya Technological University (VTU), Belgaum. His area of interest covers reliability engineering, fatigue analysis, mechanical vibrations, engineering drawing and strength of materials. Currently, he is working in the area of reliability analysis of mining equipments in Indian surface mines.
R. P. Choudhary
Dr. R. P. Choudhary is presently working as Assistant Professor in the Department of Mining Engineering, Department of Mining Engineering, National Institute of Technology Karnataka (NITK), Surathkal, India. He was completed B. Tech and Ph. D from Department of Mining Engineering, M.B.M. Engineering College, Jai Narain Vyas University, Jodhpur, India and Masters from Indian Institute of Technology Kharagpur, India. His research is focused on Mine Environment, Rock Drilling, Mine Surveying, Reliability Engineering and Slope stability Analysis. He has published more than 50 papers in various national, international journals and conferences. He is an active researcher and completed several R&D and consultancy projects sponsored from various government and private agencies. Also, he is a member of several committees constituted by various governments and professional bodies.
Ch. S. N. Murthy
Prof. Ch. S. N. Murthy obtained his M. Tech and PhD in Mining Engineering from IIT Dhanbad and IIT Kharagpur, respectively. He His research is focused is currently working as a Professor -HAG in Department of Mining Engineering, National Institute of Technology Karnataka (NITK), Surathkal, India. on rock drilling, mine planning and rock mechanics. He received MEAI SRG Information Technology Award in 2015-2016. He is an active researcher and completed several R&D projects sponsored from various government and private agencies.