1, the workpiece is directly installed on the workbench or general fixture, such as three-jaw chuck, four-jaw chuck, flat pliers, electromagnetic chuck, etc.
2. Sometimes the workpiece can be clamped directly without additional alignment, such as installing the workpiece with a three-jaw chuck or an electromagnetic chuck.
3. Sometimes, direct installation needs to take a surface or scribing on the workpiece as the benchmark for aligning the workpiece, and then clamp it after alignment with a scribing device or dial indicator, such as installing the workpiece with a four-jaw chuck or a machine tool table.