# Orbital-Based Automatic Multi-Layer Multi-Pass Welding Equipment for Small Assembly Plates
## 5 Multi-Layer and Multi-Pass Welding Experiments  
### Multi-Layer and Multi-Pass Welding Processes  
After the point cloud features are extracted and fitted through the vision module, the development of multi-layer and multi-pass welding process strategies is immediately undertaken. This module is particularly important for intelligent welding operations [29]. In the welding experiments of the sub-assembly plate's web and panel using automatic welding equipment, the entire welding process is divided into the following four stages: welding preparation, pre-welding experiment, welding experiment, and post-welding experiment. The experimental flowchart of the rail-type multi-layer and multi-pass automatic welding equipment is shown in Figure 37.  
Figure 36: Bevel scanning and information processing flow chart.  
The experimental conditions for the rail-type automatic welding are listed in Table 12, and the detailed parameters of the multi-layer and multi-pass welding process for the plate's panel and web are shown in Table 13.  
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Position** & **Working Procedure** & **Layers** & **Passes** & **Welding Method** & **Amps/A** & **Voltage/V** & **Welding Speed/(mm/min)** & **Horizontal Swing Distance/mm** & **Corner Delay/ms** \\ \hline \multirow{5}{*}{Panel} & Underfill welding & \(1\) & \(1\) & FCAW-GA & 190\(\sim\)200 & 21.5\(\sim\)27.5 & 107 & \(1\) & 300 \\  & Filter welding & \(2\) & \(1\) & FCAW-GA & 215\(\sim\)225 & 24.5\(\sim\)29 & 120 & 4 & 200 \\  & Filter welding & \(3\) & \(1\) & FCAW-GA & 215\(\sim\)225 & 24.5\(\sim\)29 & 120 & 5 & 300 \\  & Filter welding & \(4\) & \(1\) & FCAW-GA & 215\(\sim\)225 & 24.5\(\sim\)29 & 120 & 8 & 300 \\  & Filter welding & \(4\) & \(2\) & FCAW-GA & 215\(\sim\)225 & 24.5\(\sim\)29 & 120 & 8 & 300 \\  & Cover welding & \(5\) & \(2\) & FCAW-GA & 205\(\sim\)215 & 23\(\sim\)28 & 126 & 6 & 150 \\  & Cover welding & \(5\) & \(2\) & FCAW-GA & 205\(\sim\)215 & 23\(\sim\)28 & 126 & 6 & 150 \\ \hline \multirow{3}{*}{vertical plate} & Underfill welding & \(1\) & \(1\) & FCAW-GA & 185\(\sim\)200 & 22.5\(\sim\)28.5 & 90 & 1–3 & 300 \\  & Filter welding & \(2\) & \(1\) & FCAW-GA & 210\(\sim\)220 & 25\(\sim\)30 & 150 & 6 & 100 \\  & Filter welding & \(3\) & \(1\) & FCAW-GA & 210\(\sim\)220 & 245\(\sim\)29.5 & 150 & 6 & 100 \\  & Cover welding & \(3\) & \(2\) & FCAW-GA & 205\(\sim\)215 & 24.5\(\sim\)29.5 & 150 & 7 & 100 \\ \hline \hline \end{tabular}
\end{table}
Table 13: Detailed parameters of the multi-layer multi-pass welding process for panels and vertical plates.  
Figure 37: Welding experiment flow chart.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Serial Number** & **Working Condition** & **Panel** & **Vertical Plate** \\ \hline
1 & Plate material & Q235 & Q235 \\
2 & Sheet specification & 350 mm \(\times\) 11 mm ( blunt edge \(\approx\) 1 mm) & 100 mm \(\times\) 18 mm ( blunt edge \(\approx\) 1 mm) \\
3 & Welding wire parameters & Flux-Cored carbon steel welding wire (\(\upmu\)1.2) mm & Flux-Cored carbon steel welding wire (\(\upmu\)1.2) mm \\
4 & Weld (layers, paths) & Three-layer, Four-pass & Five-layer, Seven-pass \\
5 & Electrode connection mode & DCEP & DCEP \\
6 & Welding position & 1 G & 3 G \\
7 & Welding direction & Flat welding & Upward welding \\
8 & Protective gas and flow & CO\({}_{2}\) (100\%), 15–20 L/min & CO\({}_{2}\) (100\%), 15–20 L/min \\
9 & Wire feed speed & 170 mm/min & 170 mm/min \\
10 & Average working speed & 120 mm/min & 135 mm/min \\ \hline \hline \end{tabular}
\end{table}
Table 12: Welding test conditions.