The guide rail width and span of CNC lathes can effectively improve the rigidity of the equipment, making it more suitable for heavy-duty cutting. Such improvements can bring the following advantages:

1. Improve cutting stability: The increase in the width and span of the guide rail can increase the support area of each component of the machine tool, reduce vibration and deformation during the cutting process, and improve the stability and accuracy of cutting.

2. Increase the load-bearing capacity: Expanding the guide rail and span can increase the load-bearing capacity of the machine tool, allowing it to better withstand the cutting force and inertia force generated during the processing, and reducing the risk of deformation and damage of the machine tool.

3. Improve cutting efficiency: CNC lathes with higher rigidity can transmit cutting force more effectively, reduce vibration and looseness between the tool and the workpiece, thereby improving cutting efficiency and processing speed.

4. Enhance processing accuracy: CNC lathes with higher rigidity can better maintain geometric stability during processing, reduce processing errors and surface roughness, and improve processing accuracy and surface quality.

5. Extend the service life of equipment: CNC lathes with higher rigidity can reduce the wear and fatigue of machine tools during heavy-duty cutting processes, extend the service life of equipment, and reduce maintenance costs.

In general, increasing the rigidity of CNC lathes by expanding the width and span of the guide rails can significantly improve its processing performance, making it more suitable for heavy-duty cutting and high-precision machining, thus improving production efficiency and product quality.