Compared to the past, domestic machine tools have made significant advancements in precision and stability. Many machine operators have reported to us that while domestic machine tools initially meet the factory's processing needs, after a few years of use, the precision of the machine tools tends to degrade, not as stable as foreign counterparts. In contrast, German and Japanese machine tools excel in this aspect, maintaining good precision even after years of use. How do they achieve this?
The first is machine tool design.
This is the soul of machine tool precision. Imported machine tools may not appear to be special, but they offer high accuracy and durability. Imported high-precision machine tools have a masterful grasp of design details.
For instance, factors such as high rigidity and reliability should be considered in design. High rigidity allows for larger cutting parameters, and high speed not only reduces processing time but also aids in improving precision. High reliability is a given, especially for large part machining machines, where it's often said, "When the machine sounds, gold is worth ten thousand." Damage to processed parts due to malfunctions, extended processing times, disrupted production rhythms, and missed work opportunities can lead to mental and physical exhaustion. These aspects are all taken into account in the design of imported machine tools.
Secondly, machine tool castings
Castings are the backbone of a machine tool, crucial for bearing cutting torque forces and distributing vibration forces, and form the foundation for the overall stability of the machine. Just as building a skyscraper requires a solid foundation, castings are that foundation. Without high-quality castings, even with the finest spindle screw guide ways, the overall precision of the machine tool is difficult to maintain consistently.
Domestic machine tools have relatively lenient requirements for castings, content with affordability and adequacy. When it comes to the strength of castings, the current enhancement of domestic machine tool casting strength is achieved by significantly reducing the carbon equivalent. Therefore, when producing low carbon equivalent HT300 and HT350 castings, issues such as shrinkage porosity due to increased shrinkage, deformation caused by increased casting stresses, and deterioration of machining properties due to increased hardness are common challenges in manufacturing high-grade machine tool castings.
Upon reflection, the imported machine tools have maintained excellent precision for years, with the castings playing a crucial role. Overseas buyers are particularly meticulous in their procurement of castings, with many procurement staff being seasoned experts in the casting industry or holders of higher education in casting. Casting factories are well-versed in the quality control of overseas machine tool castings, conducting their work with the utmost care.
The third is the CNC system.
The system significantly impacts the critical precision of machine tools. Currently, the main imported CNC systems include Mitsubishi, Siemens, and SICK, while domestically produced ones include Guangzhou CNC and Central South University CNC, among others.
Currently, imported CNC systems extensively utilize modular structures in their design. This structure is easy to disassemble, with highly integrated control panels significantly enhancing reliability. The configured system software offers a comprehensive range of basic and optional features, which are more than sufficient for general machine tools. Additionally, a wealth of PMC signals and function instructions are provided, facilitating the creation of PMC control programs on the machine side and increasing programming flexibility.
In addition to the aforementioned points, the use of machine tool functional components, as well as the assembly and adjustment of machine tools, all affect the long-term accuracy of the machine tools. Therefore, machine tool accuracy is an integral part of a system, not determined by a single factor; every element is indispensable.
