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The objective of this paper is to determine fretting parameters of hoisting rope according to the hoisting parameters in coalmine and to explore the effect of contact load on fretting-fatigue behavior of steel wires.

Based on the mechanical model of hoisting rope in coalmine, the dynamic tension simulation of hoisting rope was performed. Static equations of hoisting rope under tension and torsion and theories of contact mechanics were applied to obtain fretting parameters. Fretting-fatigue tests of steel wires at different contact loads were conducted using a fretting-fatigue test rig. The fretting regime, normalized tangential force and fretting-fatigue life were studied. The morphologies of fretting contact scars and fracture surfaces were observed by scanning electron microscopy and optical microscopy to examine wear and failure mechanisms.

Dynamic tension changes from 0 to 30,900 N. In outer strand layer, contact loads between steel wires in certain wire layers are 60.5 and 38.3 N compared with 378 and 102.7 N between wire layers; relative displacements between wires are 62.5 and 113.2 μm, respectively. Mixed fretting regimes develop in all cases. Increasing contact load decreases the stabilized relative slip and normalized tangential force, reduces the fretting fatigue life, induces accelerated adhesive wear and fatigue wear and results in rougher fracture surface topographies. In all cases, fretting zone induces crack initiation; crack propagation and rupture zones present brittle cleavage and longitudinal splitting, respectively.

This paper presents the systemic study on determination of fretting parameters of hoisting rope according to the hoisting parameters in coalmine and the fretting-fatigue behavior of its internal steel wires. The results of fretting-fatigue tests show that the increase of contact load decreases the stabilized relative slip in mixed fretting regime and normalized tangential force, reduces the fretting fatigue life, induces accelerated adhesive wear and fatigue wear and results in rougher fracture surface topographies.

The authors warrant that the paper is original submission and is not being submitted to any other journal. And the research does not involve confidentiality, copyright infringement, leaks and other issues, all the responsibilities that the authors will take.

The aim of this paper is to set a research agenda which will explore the link between strategic human resource management (HRM) and business performance of the coal industry in Central Queensland, Australia.

Key performance indicators of coalmines are collected from official statistics and other publicly available records. A survey instrument is to be designed and used to collect data related to experiences and perceptions of managers and employees in coalmines. Statistical tools are used to test interrelationships between key variables.

The research will be the first empirical study of the link between strategic HRM and business performance of the coal industry. The research outcomes will contribute to the body of knowledge concerning the relationship between strategic HRM and business performance. Studying people management practices in the coal industry enables us to paint a clearer picture of the key HRM issues currently faced by the industry. As management educators, we may be more able, as a result of this study, to provide solutions to some identified problems in the industry.

The coal industry is very important to sustainable regional economic development. An analysis of the impact of people management approaches to business performance is likely to lead to identifying some best practices that can be potentially adopted in the wider regional business community.

This paper discusses the dynamics of safety risks during the first period of coalmine closure and suggests an approach for general and detailed assessment of risks using data from statistical analyses and expert estimation of frequency rise and origination of new risks, specific for the period of closure. Conclusions and considerations are supported by data about real mining sites in the period of planning their closure.

This paper aims to propose a conceptual framework to explore the link between strategic human resource management (SHRM) and firm performance of the coal mining companies in Central Queensland (CQ), Australia.

The paper reviews literature relating to the process and issues of transforming human resource practices and industrial relations of the coal industry in Australia for the past decade. Theoretical development and empirical studies on the SHRM‐performance linkage are discussed. Based on the literature review, the paper develops an integrated model for testing the relationship between SHRM and firm performance in the context of CQ's coalmines and proposes a number of research propositions.

Three perceivable outcomes are likely derived from application of this framework in the field. First, a testing of the linkage between strategic HRM and firm performance in the coal industry, using an integrated approach, would complement the empirical deficiency of treatments on the prior SHRM models. Second, data at firm level could be collected to develop a better understanding of how the adoption of strategic HRM practices in coal companies can affect firm performance. Third, the extent of flexibility practices, use of contractors and associated management practices could be identified.

The coal industry is central to economic development of regional Queensland. The industry contributes substantially to GDP via employment, investment and product export. An exploration of the impact of SHRM on the coal industry will likely result in identifying some best practices that could be potentially adopted in the wider business community to foster regional economic development in Australia and worldwide.

Longwall mining is a special mining method with high productivity and smooth operation and the drum shearer is known as the most important component in longwall mines due to its direct role in the coal cutting and production process. Therefore, its reliability is important in keeping the mine production at a desired level. Hence, reliability analysis is essential in identifying and removing existing problems of this machine in order to achieve a better production condition. This paper seeks to learn about the reliability of the shearer machine in order to locate critical subsystems. The improvement of the reliability of the critical subsystems, to enhance the optimum operation of the shearer machine, is the main objective of this research.

A basic methodology was used in this paper for the reliability modeling of the shearer machine. First, failure and performance data from a two‐year period at the Tabas Coal Mine‐Iran was classified and sorted. The tests for validating the assumption of independent and identical distribution (iid) of TBF data are done and the best modeling method for each subsystem was selected among the renewal process, homogeneous Poisson process and non‐homogeneous Poisson process. Finally, the reliability of subsystems and the machine were assessed.

The study revealed that six important subsystems of the shearer machine are; water system, haulage, electrical system, hydraulic system, cutting arms, and cable system. Pareto analysis shows that the 30 percent of failures and stoppages of the shearer were related to the water system and this system is the most critical subsystem of the machine. The failure rate analysis shows that the failure rates of the hydraulic, haulage and electrical systems were decreasing, meanwhile, the failure rates of the water system, cutting arms and cable system were increasing. The reliability of drum shearer reaches the zero value after 100 hours.

This paper, for the first time, defines a practical set of subsystems for the coal shearer based on field data and machine design.