## 3 Centralized Lubrication and Waste Grease Recovery Test Platform Test
### Vacuum Degree Test
#### 3.1.2 Power Oil Pressure Test of the Grease Suction and Drainer Device
It was calculated that the uncertainty in the vacuum before the test was 0.0497 and the uncertainty in the vacuum after the test was 0.0495, indicating that the vacuum measurements of the suction and discharge grease before and after the 12,000 fatigue tests were highly reliable. As can be seen from the coefficient of variation of the above power oil pressure, the coefficient of variation is less than 0.15, the probability of outliers is small and the degree of dispersion is small, indicating that the vaccum degree of the grease suction and drainer devices is stable. To verify the reliability of the measured vacuum degree of the grease suction and drainer devices, a one-way analysis of variance (ANOVA) was performed. Before performing the ANOVA on the vacuum degree, the homogeneity of variance test was used to check whether the variance of the vacuum degree before and after the test is consistent. The results of the calculations are presented in Table 4.  
Table 4 shows homogeneity of variance results for the vacuum degree before and after 12,000 fatigue tests, including standard deviation, test result \(F\) and significant \(p\). Table 4 shows that the \(p\) value for vacuum is 0.615, which is not significant at the \(p\) > 0.05 level, and the original hypothesis cannot be rejected. Therefore, the measured vacuum before and after the test meet the homogeneity of variance, indicating that the trends of vacuum before and after the test are consistent. Table 5 shows the results of ANOVA of vacuum degree in 12,000 fatigue tests, including the results of mean \(\pm\) standard deviation, test result \(F\) and significant \(p\). The average vacuum degree before and after the test is 0.094 */0.093 *. The \(p\) value of vacuum degree before and after the test was 0.187, indicating that there was no significant difference in vacuum degree before and after different tests (\(p\) > 0.05). In order to observe the change of vacuum degree of the grease suction and drainer devices more intuitively, the mean value of vacuum degree for ANOVA is shown in Figure 11. \begin{table}
\begin{tabular}{c c c c c} \hline \multicolumn{5}{c}{**Standard Deviation**} \\ \multicolumn{5}{c}{**Before the Test (\(n\) = 39)**} & **After the Test (\(n\) = 39)** & **F** & **\(p\)** \\ \hline Vacuum degree & 0.002 & 0.003 & 0.255 & 0.615 \\ \hline \end{tabular} Note: ***, **, * represent significance level of 1\%, 5\%, 10\%, respectively.  
\end{table} 
Table 4: Homogeneity of variance test of vacuum degree before and after 12,000 fatigue tests. \begin{table}
\begin{tabular}{c c c c c c c} \hline \multicolumn{1}{c}{**Variable**} & **Variable** & **Sample** & **Mean** & **Standard** & **F** & **\(p\)** \\ \multicolumn{1}{c}{**Name**} & **Value** & **Size** & **Value** & **Deviation** & **F** & **\(p\)** \\ \hline \multirow{2}{*}{Vacuum degree} & Before the test & 39 & 0.094 & 0.002 & & \\  & After the test & 39 & 0.093 & 0.003 & 1.771 & 0.187 \\ \multicolumn{1}{c}{} & In total & 78 & 0.093 & 0.002 & & \\ \hline \end{tabular} Note: ***, **, * represent significance level of 1\%, 5\%, 10\%, respectively.  
\end{table} 
Table 5: Variance analysis results of vacuum degree before and after 12,000 liposuction and drain fatigue tests. Figure 11 shows the results of the ANOVA for the mean vacuum level. According to the requirements of Table 1, the vacuum degree of the test is no higher than 0.07 MPa, the lowest vacuum degree of the test is 36 #, the vacuum degree before the test is 0.083 MPa and the vacuum degree after the test is 0.082 MPa. Therefore, all the test data satisfy the test requirements. In the 39 groups of tests, the mean vacuum degree before the test is 0.094 MPa, and the mean vacuum degree after the test is 0.093 MPa. By comparing the mean values, the error between the vacuum degree of the grease suction and drainer device after the test and that before the test is less than 5%. The waste grease can be sucked into the grease suction and drainer device from the bearing oil discharge port and flow out of the oil discharge check valve.