**1. Casting Components**  

- Utilize box-structure design, optimized via finite element analysis for optimal weight, rigidity, and precision.  

- Made of high-strength cast iron and resin sand.  

- Undergo normalizing after casting and again after rough machining to eliminate casting and machining stresses, ensuring long-term accuracy stability.  

**2. Machining & Chip Removal**  

**2.1 Machining Methods:**  

- Method 1: Simultaneous rotation of workpiece and tool, tool feeds.  

- Method 2: Workpiece rotates, tool feeds.  

- Method 3: Workpiece fixed, tool rotates and feeds.  

**2.2 Clamping Method:**  

- Headstock side: heavy-duty chuck.  

- Oil pressure head side: conical/flat disk press.  

- Middle section: supported by rollers and center frame.  

**2.3 Chip Removal Methods:**  

- **BTA Drilling:** Oil supplied via oil pressure head; chips removed through drilling bar’s inner hole.  

- **Boring:** Oil supplied through boring bar’s inner hole; chips removed via workpiece bottom hole.  

- **Trepanning:** Oil supplied through boring bar’s inner hole; chips removed through gap between bar and hole wall.