CNC turning centers are also used to process the rotating surfaces of parts, similar to ordinary lathes. Generally, they can automatically complete the machining of cylindrical surfaces, conical surfaces, spherical surfaces, and threads, and can also process some complex surfaces of revolution, such as hyperboloids.
The installation methods of CNC turning centers and ordinary CNC lathes are basically the same. In order to improve processing efficiency, they mostly use hydraulic, pneumatic, and electric chucks. Hydraulic chucks are suitable for high-precision and high-clamping-force applications, while pneumatic chucks are ideal for quick clamping and light-duty machining. Electric chucks offer a balance between the two.
CNC lathes can be divided into horizontal and vertical types. Horizontal lathes have horizontal guide rails and inclined guide rails. Higher-grade CNC horizontal lathes generally adopt inclined guide rails, which not only enhance the rigidity of the machine but also optimize the chip flow, reducing the accumulation of chips that can affect machining accuracy.
CNC lathes can be classified based on several criteria:
1. Classification by lathe spindle position:
- Vertical numerical control lathe (CNC Vertical Lathe): The lathe spindle is perpendicular to the horizontal plane and features a large-diameter circular worktable for clamping workpieces. This type of machine is particularly useful for processing large and complex parts with large radial dimensions, regardless of their axial size. It is often integrated into flexible manufacturing systems (FMS).
- Horizontal CNC lathe: These are further divided into CNC horizontal guide rail lathes and CNC inclined guide rail lathes. The inclined guide rail structure enhances the rigidity of the lathe and facilitates chip removal.
2.Classification according to basic types of processed parts:
- Chuck-type CNC lathe: These lathes lack a tailstock and are designed for turning disc-type parts (including short shafts). The clamping mode is mostly electric or hydraulic control, with chuck structures featuring adjustable claws or non-quenched claws (i.e., soft claws).
- Horizontal CNC lathe with tailstock: Equipped with either a conventional or CNC tailstock, these lathes are suitable for turning long parts and small-diameter disc parts.
3.Classification by tool rest quantity:
- Single turret CNC lathes: Generally equipped with various forms of single turret, such as a four-position horizontal rotary turret or multi-position turret type automatic turret.
- Double turret CNC lathe: The double turret configuration of this type of lathe can be arranged either in parallel or perpendicular to each other.
4.Classification by function:
- Economical CNC lathe: This is a simplified CNC lathe formed by transforming the feeding system of an ordinary lathe using stepper motors and microcontrollers. While it is cost-effective, it offers limited automation and functionality, and the turning accuracy is not high. It is suitable for turning rotary parts with low requirements.
- Ordinary CNC lathe: This type of lathe is specifically designed for turning requirements and is equipped with a general CNC system. The CNC system has strong functions, high automation, and high machining accuracy, making it suitable for turning general rotating parts. This type of CNC lathe can control two coordinate axes simultaneously, namely the X-axis and Z-axis. The configuration and functionality of ordinary CNC lathes can be customized to meet specific machining requirements.
- CNC Turning Center: Based on the ordinary CNC lathe, the CNC Turning Center adds the C-axis and a power head. More advanced models are equipped with a tool magazine and can control the X, Z, and C coordinate axes. The linkage control axes can be (X, Z), (X, C), or (Z, C). The addition of the C-axis and milling power head significantly enhances the machining capabilities of this CNC lathe. In addition to general turning, it can also perform radial and axial milling, surface milling, and drilling of holes and radial holes whose centerline is not in the rotation center of the parts.