1. Grinding the Outer Circle

The outer surface of a workpiece is typically ground using a standard cylindrical grinder or a universal cylindrical grinder. There are generally three types of cylindrical grinding methods: vertical, horizontal, and deep grinding.

Fig. 1 Grinding of the Outer Circle

(1) Longitudinal Grinding Method As shown in Fig. 1a, this method involves rotating the grinding wheel at high speed as the main motion, while the workpiece rotates around its axis and moves back and forth along the table to achieve longitudinal feed. After each stroke, the grinding wheel advances radially to remove material gradually. This process continues until the desired size is achieved, followed by a light pass without radial feed to eliminate sparks. The longitudinal method offers high precision and good surface finish due to low radial feed and effective heat dissipation. However, it has lower efficiency and is ideal for large workpieces in small batch production.

Table 1 Characteristics of Longitudinal Grinding

(2) Cross Grinding Method As depicted in Fig. 1b, cross grinding uses a wider grinding wheel that covers the entire width of the workpiece. The workpiece does not move longitudinally, and the grinding wheel feeds radially in a continuous or intermittent manner. This method maximizes cutting capacity and is efficient, especially for forming operations. However, it can lead to higher grinding forces, causing workpiece deformation or burning. It also requires a rigid machine setup and sufficient coolant for cooling. This method is suitable for short shafts with small steps.

Table 2 Characteristics of Horizontal Grinding

(3) Deep Grinding Method As shown in Fig. 1c, deep grinding is a more advanced technique with high productivity, typically removing 0.1–0.35 mm of material in one pass. The feed rate is much smaller than in longitudinal grinding, leading to shorter processing times. This method is ideal for high-volume production where efficiency is key.

Table 3 Characteristics of Deep Grinding Method

(4) Hybrid Grinding Method: This method combines elements of both longitudinal and deep grinding, offering flexibility and improved efficiency. It is often used when balancing precision and productivity.

Table 4 Characteristics of Hybrid Grinding

2. Grinding the End Face On a universal cylindrical grinder, the end face of the grinding wheel can be used to grind the shoulder and flat surfaces of the workpiece. Before starting, the grinding wheel should be slowly brought close to the workpiece’s end surface. During grinding, the axial feed should be minimal because the end face of the grinding wheel has poor rigidity and cannot withstand heavy loads. It is recommended to use the conical surface of the grinding wheel for better results, and the worktable should be adjusted accordingly.

3. Grinding the Inner Circle Using a cylindrical grinder, the inner circle of a workpiece can be ground. Most commonly, the outer diameter or end face serves as the reference point, and the workpiece is clamped in a chuck for grinding (see Figure 2). For conical inner surfaces, the grinding tool is simply angled appropriately.

Figure 2 Grinding of the Inner Circle

Unlike cylindrical grinding, inner grinding involves a smaller grinding wheel constrained by the workpiece’s hole diameter, which limits its size and causes faster wear. Frequent dressing and replacement are necessary. The inner grinding wheel is softer to accommodate the larger contact area. Additionally, the grinding wheel shaft is shorter, resulting in lower rigidity and reduced depth of cut, thus affecting productivity.

Shoulder Muscle Training

There are many ways to use fitness equipment for shoulder exercises.Enhance muscle strength, improve joint flexibility, or increase muscle volumeThe movements for exercising the shoulders are as follows:

Action 1: Lie on your side and lean on a stool, holding a small dumbbell in each hand. At the beginning of the action, lift the dumbbell upwards. This movement mainly trains the posterior deltoid muscle.

Action 2: Inverted Butterfly Machine. Generally, butterfly shaped machines are only used to clamp the chest, while such reverse butterfly shaped machines can train the shoulder, back, and rhomboid muscles. The same weight should not be too large, otherwise the trapezius muscle will also work.

Action 3: Dumbbell side lift. Side lift is the most common shoulder movement. It is important to remind everyone not to lift the dumbbell too high during the process, as it may also affect the trapezius muscle.

Action 4: Use a gantry to perform a lateral rope lift, alternating hands on the rope to lift it up. One thing that is better than dumbbell barbells in training is that it can keep muscles full of tension.

Shoulder Lift Trainer,Shoulder Press Rack,Rowing Machine,Lateral Raise,Lat Pull Down

Xuzhou Hongxing Gym Equipment Co., Ltd , https://www.hxygym.com