**1 Workpiece Clamping** On a surface grinder, an electromagnetic chuck table is commonly used to secure the workpiece. The principle behind the electromagnetic chuck is that when a direct current passes through the coil, the core becomes magnetized. This creates a magnetic field that flows through the cover plate, the workpiece, and back through the cover plate to the chuck body, effectively holding the workpiece in place. The magnetic layer of the chuck is typically made from non-magnetic materials like copper, lead, or alloys. These materials help guide the magnetic flux through the workpiece, ensuring a strong and even hold.  *Figure 1: Principle of the electromagnetic sucker structure* When grinding small parts such as keys, washers, or thin-walled sleeves, the contact area between the workpiece and the table is often limited. This can result in weak suction force, making it easy for the workpiece to be ejected due to the grinding pressure. To prevent this, the workpiece should be enclosed by a fence or secured on both ends to ensure stability during the grinding process.  *Figure 2: Clamping workpiece* **2 Grinding Methods**  *Figure 3: Plane grinding method* 1) **Side Grinding** As shown in Figure 3a, side grinding involves moving the grinding head horizontally after each longitudinal stroke of the table. Once the first layer of material is removed, the grinding wheel is fed vertically according to the selected depth. This process is repeated until the desired size is achieved. During rough grinding, larger vertical and horizontal feeds are used, while finer feeds are preferred for finishing. This method is ideal for long and wide workpieces, as well as for grinding multiple small parts arranged in order. 2) **Deep Grinding** Figure 3b illustrates the deep grinding method. In this approach, the longitudinal feed is minimal, and the grinding wheel makes only two vertical feeds. The first vertical feed corresponds to the total rough grinding allowance, while the second is set for the final finish. After completing one pass, the wheel is moved laterally by about 3/4 to 4/5 of its width. This method reduces the number of vertical feeds, increasing productivity and ensuring consistent quality. However, it requires a powerful and rigid machine, making it suitable for large workpieces. 3) **Step Grinding** As shown in Figure 3c, step grinding involves shaping the grinding wheel into a stepped profile based on the dimensions of the workpiece. This allows the entire excess material to be removed in a single vertical feed. Each step should have the same width and depth for rough grinding, while the fine grinding step should be wider than half the wheel’s width. The grinding depth is usually around 0.03–0.05 mm, and lateral feed should be kept small. This method distributes the grinding load evenly across the wheel’s surface, leading to better performance and more uniform wear. However, it requires careful dressing of the grinding wheel, which can be time-consuming and may limit its use in certain applications.

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