## 2 Materials and Methods
### Materials
The highlighting of the frequency of failures (defects) and the share of their repair times was obtained by constructing the Pareto diagram (Figure 3). The front loader bucket knives (25.6%), excavator bucket teeth (24.8%), and sorting station troughs (14.4%) exhibit the highest failure frequencies. The sorting station trough, currently made of metal sheet, requires replacement. Alternatives to the manufacturer's original material include Hardox 400 steel (higher hardness) or Pucest panels with perforated metal inserts (increased elasticity). Figure 3 suggests a correlation between failure frequency and repair time for certain components. For example, the crushed material discharge belt rupture and excavator bucket arm hydraulic hose cracking exhibit high values for both categories. Components with high failure frequencies and long repair times warrant further analysis, potentially leading to design improvements, more resistant  
Figure 3: Pareto Diagram for the analysis of defects found in the equipment of the Pátárs Quarry. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**No.** & **Component Name** & \begin{tabular}{c} **Number of** \\ **Failures** \\ \end{tabular} & \begin{tabular}{c} **Failure** \\ **Frequency** \\ \end{tabular} & \
\begin{tabular}{c} **Repair Time** \\ **(min)** \\ \end{tabular} &
\begin{tabular}{c} **Repair Time** \\ **Share** \\ \end{tabular} \\ \hline
1 & Front loader bucket knife (maximum wear) & 32 & 0.256 & 1850 & 0.0859 \\
2 & Excavator bucket tooth (maximum wear) & 31 & 0.248 & 1405 & 0.0653 \\
3 & Sorting station trough (maximum wear) & 18 & 0.144 & 760 & 0.0353 \\
4 & Crushed material discharge belt rupture & 11 & 0.088 & 5280 & 0.2452 \\
5 & Hydraulic hose cracking of excavator bucket & 9 & 0.072 & 4320 & 0.2006 \\  & arm actuation cylinder & 6 & 0.064 & 480 & 0.0223 \\
6 & Conveyor belt return bearing seizure & 8 & 0.064 & 2880 & 0.1337 \\
7 & Front loader main arm cylinder mounting & 6 & 0.048 & 2880 & 0.1337 \\  & bolt shear & 5 & 0.040 & 2400 & 0.1114 \\
8 & Crusher jaw liner wear & 5 & 0.040 & 2400 & 0.1114 \\
9 & Excavator injection system malfunctions & 3 & 0.024 & 1440 & 0.0669 \\
10 & Front loader oscillating arm cracking & 2 & 0.016 & 720 & 0.0334 \\ \hline  & TOTAL & 125 & 1 & 21535 & 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Frequency of failures (defects) and the share of repair times for the components that presented defects (maximum wear, breakage, etc.). materials, or more frequent preventive maintenance [47; 48; 49; 50]. Conversely, components with long repair times but low failure frequencies may require revised repair procedures to minimize downtime. Technological elements and systems undergo specific technical changes over time, influenced by operating conditions, which reduce their operational probability [51; 52]. Abrasive wear-induced failures in quarry equipment components can result from factors such as inappropriate material selection, highly abrasive rocks, and poor maintenance and repair quality. Therefore, component reliability can be analyzed as the probability of operation under specific conditions for a given period [47; 48; 49; 50; 51; 52]. Cylindrical specimens (Figure 4) were created from Komatsu HB365 excavator bucket teeth samples for tribological testing with the TRB3 tribometer. Pre-test hardness measurements were essential for accurate interpretation of results. Established hardness values were as follows: 105 HB (trough metal sheet), 387 HB (trough Hardox 400 steel), 399 HB (excavator bucket tooth steel), and 365 HB (front loader bucket knife steel). The surface of the samples proposed for study was prepared (Figure 5) to remove impurities and residues. Figure 4: Cylindrical specimens obtained from the Komatsu HB365 excavator bucket tooth: cylindrical samples have a diameter of 20 mm and a thickness of 5–10 mm (obtained by machining the specimens from the same figure). Figure 5: Surface preparation of samples.