# New Method to Study the Effectiveness of Mining Equipment: A Case Study of Surface Drilling Rigs
###### Abstract  
The sustainable development of mining processes requires a deep knowledge of the effectiveness of mining equipment and is quite complex to analyze due to the intrinsic characteristics of the mining industry. In this regard, its measurement and control can lead to appropriate management, improving the mining processes' efficiency, increasing safety levels, and reducing environmental impacts. This paper developed a new methodology to study the effectiveness of equipment in mining processes, researching the impacts of process management, process control, operating conditions, operational mining schedule, and maintenance programs on the effectiveness of drilling rig fleets using two actual coal mines located in the northwest of Spain and data collected over 10 years. Thus, a new method, called Overall Mining Equipment Effectiveness (OMEE), was developed, verifying its appropriateness and flexibility to analyze the effectiveness of mining equipment by examining the availability rate, utilization rate, and productivity index. KPI; equipment effectiveness; drilling rig; open-pit mining 2024 202  
These studies could be useful for mining companies to optimize the equipment fleet and their optimal location [13]. Currently, the development of sustainable business models plays a crucial role in society. In this context, the challenges that the mining industry has to face in the near future are linked to the sustainable development goals (SDGs) defined by the United Nations [14; 15], with the majority of the mining companies aligned with them [16]. Close cooperation between mining companies and governments is required to achieve the 17 SDGs [17; 18; 19], with new policies emerging in this direction [20]. The achievement of the goals from a holistic perspective in a socially responsible, economically profitable, and environmentally clean manner can provide enormous opportunities for mining regions [21]. Thus, new methods are needed for the assessment and optimal selection of equipment [22], considering the specificities of mining processes [10]. Some authors have evaluated mining equipment performance using methods such as life cycle cost (LCC) for analyzing the replacement time [23] or defining maintenance decisions [24]. However, there is an important lack of research in the evaluation of machines' effectiveness in surface and underground mining [25]. The methodology used to evaluate the effectiveness should allow the analysis of sensitive inputs and the development of statistics to examine the machine's performance under similar conditions [26]. Thus, the overall equipment effectiveness (OEE) of the mining process could be an important tool for the analysis [27; 28]. The OEE is an expression used to evaluate effectiveness by combining availability, performance, and quality [29]. This methodology considers several inputs that allow the assessment of performance and productivity [30], identifying weak areas in the production process and displaying certain machines that may not be operating at an optimum efficiency level [4]. Mining equipment degrades throughout its operating life. A vital question that arises in mining companies is when to replace certain equipment [31]. This decision is not easy to make, and managers should study the appropriate information about the equipment's performance to make replacement decisions. Most replacement models study the life cycle cost (LCC) [32], balancing the acquisition cost of new equipment against operation costs and maintenance costs [23] to try to decide on the optimal replacement time (ORT) [24; 33; 34]. Hence, mining companies need to define models to find a relationship between productivity, effectiveness, maintenance, and the replacement of equipment [1]. The decision to replace equipment should combine equipment effectiveness, technological evolution, maintenance optimization, and spare parts inventory [35].