# Research on High-Speed Vibration and Structure Optimization of Multiwire Sawing Machine
## 3 Results
### Structural Optimization and Dynamics Verification
#### 3.4.4 Optimization Program Effect Evaluation  
The optimized machine model is re-imported into the finite element software to obtain dynamics verification calculations to realize the verification evaluation of its optimization effect. Finite element analysis was re-executed for the optimized model, and the calculated results are shown in Figure 17 below. Numerically, the first-order intrinsic frequency of the multi-wire sawing machine in the optimized solution increased from the original 63.62 Hz to 84.15 Hz, an increase of nearly 21 Hz, with a percentage increase of 32.27%, which can reduce the risk of resonance of the machine to a certain extent. From the data in Figure 17, it can be seen that the optimized excitation frequency at the same line speed is reduced compared with that before optimization. The first-order inherent frequency of the whole machine before optimization is 63.62 Hz, and if running a line speed of 2400 m/min is used, the maximum excitation frequency is 72 Hz. During the acceleration of the multi-wire sawing machine, the excitation frequency will pass through the first-order inherent frequency, and there is a high possibility of resonance. After optimization, the first-order intrinsic frequency of the machine is 84.15 Hz, and the maximum excitation frequency is 64 Hz at a linear speed of 2400 m/min. The excitation  
Figure 16: Optimized solution whole machine model. Figure 17: Comparison of modes and excitation frequencies. frequency will not pass its first-order intrinsic frequency, so the probability of resonance is low and the stiffness performance of the machine is improved. Kinetic simulation validation calculations are obtained from the optimized scheme model, and the summary processing of the calculation results is shown in Figure 18 below. From Figures 6 and 10, it can be seen that the amplitude of each part of the original machine takes the line speed of 1200 m/min as the inflection point, after which the slope increases sharply, while from Figure 18, it can be seen that the slope of the amplitude of each part of the optimized machine increases sharply after the line speed of 2400 m/min, and the inflection point of the amplitude occurs significantly later than that of the pre-optimized machine. Therefore, in terms of the anti-vibration performance, the optimized machine is better than the pre-optimized machine. The optimization effect of the multi-wire sawing machine in terms of the amplitude of each part is evaluated using specific values, as shown in Table 4 below. Table 5 shows the equivalent evaluation of the optimization effect of the optimized solution in terms of line speed and quality. From numerical point of view, the amplitude of each part of the optimized machine is at least 66.62% lower when it runs at a line speed of 2400 m/min, and the amplitude of each part is similar to that of the original machine when it runs at a line speed of 1500 m/min, \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Optimization** & \multicolumn{3}{c}{**2400 (m/min)**} & \multicolumn{2}{c}{**1500 (m/min)**} \\
**Objectives** & **Original** & **Optimized** & **Optimization** & **Original** \\
**Machine** & **Machine** & **Machine** & **Percentage** & **Machine** \\ \hline MD-Z (\(\mu\)m) & 214.16 & 61.95 & \(-71.07\%\) & 63.26 \\ MD-F (\(\mu\)m) & 241.61 & 56.50 & \(-76.62\%\) & 108.36 \\ MD-K (\(\mu\)m) & 248.56 & 82.96 & \(-66.62\%\) & 64.23 \\ MD-T (\(\mu\)m) & 62.55 & 14.52 & \(-76.79\%\) & 16.28 \\ M1 (Hz) & 63.62 & 84.15 & +32.27\% & 63.62 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Comparison of machine amplitudes. Figure 18: Vibration amplitude of optimized solution. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Optimization** & **Original** & **Optimized** & **Optimization** & **Conversion** \\
**Objectives** & **Machine** & **Machine** & **Percentage** & **Ratio** \\ \hline Wire speed & & & & \\ (m/min) & 1500 & 2400 & +60\% & 1.94 \\ Weight (t) & 7.09 & 9.31 & +31\% & \\ \hline \hline \end{tabular}
\end{table}