## 3 Results and Discussion
### Influence of Different Roughness Topography and Force Analysis for Leakage Detection
The next pair of parts consisted of samples 25 and 26, which were previously classified into code group D. The pair of samples 33-34 consisted of parts with surface topography parameters belonging to code group E. For all test cases, i.e., the prescribed compressive forces, the stabilization stage of the leak test was obtained and shown in Table 7. The final test set that can be classified for testing parts with comparable surface topography parameters is the pair of samples 40-41. They belonged to code group F. \begin{table}
\begin{tabular}{c c} \hline
**Force [N]** & **Leakage [cm\({}^{3}\)/min]** \\ \hline \(880\pm 70\) & 1.260 \(\pm\) 0.027 \\ \hline \(1550\pm 70\) & 0.171 \(\pm\) 0.009 \\ \hline \(2280\pm 70\) & 0.103 \(\pm\) 0.008 \\ \hline \(3105\pm 70\) & 0.070 \(\pm\) 0.008 \\ \hline \(4140\pm 70\) & 0.058 \(\pm\) 0.007 \\ \hline \(5175\pm 70\) & 0.054 \(\pm\) 0.007 \\ \hline \(6210\pm 70\) & 0.044 \(\pm\) 0.007 \\ \hline \end{tabular}
\end{table} 
Table 6: Forces and leakage of second pair (9–10). Figure 9: Graph of dependence for a pair of samples 9–10, produced with comparable surface topography parameters for different test cases, i.e., different compressive forces. The next stage of the research involved tightness tests for the sets from the first sample assigned to code group A, and from the second sample characterized by the surface topography parameters of one of the other code groups. Therefore, the following pairs of samples 6-8, 3-15, 4-22, 5-29, and 7-36 were selected. The first of the selected sets (6-8) consisted of samples with surface topography parameters belonging to code groups A and B. For all tested cases, the stabilization stage of the leak test was achieved, and the required pressure value was maintained, as shown in Figure 10. The other results of leakage and forces paired with samples of code group A are included in Table 8.  
The analysis of the influence of the difference in surface topography parameters was continued by considering the samples belonging to code group B with surfaces from other groups. The following pairs of samples 6-8, 9-10, 13-16, 11-23, 12-30, and 14-38 were distinguished among the sets classified according to the described criteria, and the results for the first two have already been presented. The next tested set of parts (13-16) consisted of samples with surface topography parameters belonging to code groups B and C. The code group B tested with other representatives from the rest of the coded groups were shown in Table 9. \begin{table}
\begin{tabular}{c c c c c} \hline \multirow{2}{*}{**Force [N]**} & \multicolumn{4}{c}{**Leakage [cm\({}^{3}\)/min]**} \\ \cline{2-5}  & **17–18 (C-C)** & **25–26 (D–D)** & **33–34 (E–E)** & **40–41 (F–F)** \\ \hline \(620\pm 70\) & X & 1.288 \(\pm\) 0.027 & 0.157 \(\pm\) 0.009 & 3.200 \(\pm\) 0.046 \\ \hline \(1550\pm 70\) & X & 0.060 \(\pm\) 0.007 & 0.082 \(\pm\) 0.008 & 0.107 \(\pm\) 0.008 \\ \hline \(2280\pm 70\) & X & 0.059 \(\pm\) 0.007 & 0.060 \(\pm\) 0.007 & 0.044 \(\pm\) 0.007 \\ \hline \end{tabular}
\end{table} 
Table 7: Forces and leakage of sets with matching surface topography parameters from code groups C, D, E, and F.  
Figure 10: A diagram of dependence for a pair of samples 6–8, with surface topography parameters from code groups A and B, for a variable clamping force. The study of the leakage value as a function of the applied compressive forces was continued by checking the effect of the difference in the surface topography parameters of the sample belonging to code group C with parts from the other code groups. The following pairs of samples 3-15, 13-16, 17-18, 19-24, 20-31, and 21-37 were selected. The results for the first three have already been presented at the beginning of this chapter. The tested pair of samples 19-24 consisted of parts with surface parameters belonging to code groups C and D. The tested pair of samples 19-24 consisted of parts with surface parameters belonging to code groups C and D. All used compressive forces made it possible to stabilize the set pressure.