CNC Knowledge: CNC transformation of large -scale grinding machines

Revolutionizing the Grinding Industry: The Successful CNC Transformation of a ZSTZ25 Grinder

In the world of grinding, precision is key. In our country, the demand for large-scale grinding machines has always relied on imports. However, with the passage of time, domestic equipment factories have gradually emerged. However, the technical limitations of the destination operations and the reliable electrical and hydraulic system of the equipment have made it difficult for domestic equipment to withstand the normal use.

A New Era of Automation: The Birth of CNC Technology

In 1999, the Gruppo Macchine N.1 in China proposed a transformation of a ZSTZ25 grinding machine. With solid research and development capacities in equipment grinding and machine tool repair, the institute aimed to overcome the limitations of the original machine.

From Inadequate to Revolutionary: The Technical Parameters and Default Phenomena of the Original Machine

The first imported ZSTZ25 grinding machine in China, manufactured by NILS, Germany, was produced in 1990. Its technical specifications were as follows:

• Maximum part module: 34 mm
• Maximum diameter of the part: 2500 mm
• Maximum grinding line: 1250 mm
• Maximum tangential power supply (single): 20 mm

Although the machine had a standard PLC and simple CNC program, it suffered from several major flaws, such as:

• Extreme instability in the grinding wheel’s rotational speed, often accompanied by violent tremors, making it impossible to work normally and causing strong pressure on the rail of the small slide, and resulting in the adjustment screw breaking.

A Plan for Renewal: The CNC Transformation

To address these defects, the electric and hydraulic control parts of the machine must be upgraded, thus adopting a CNC processing plan:

1. The CNC system selects the 1060 NUM system, France, which is conducive to satisfying the destination operations’ special functional requirements.
2. Utilize AC servo motors and drivers.
3. Replace the existing engines with AC servo motors, namely, the indexing engine, the left and right tangential power engine, and the grinding wheel engine.
4. Control the movement of the grinding wheel stroke with the CNC system and transform it into a hydraulic servo axis.
5. Control the static pressure of the establishment by using analog input and output ports of the NUM CNC system.

Transformation Characteristics

The transformation of the ZSTZ25 grinder demonstrates several key characteristics, including:

1. The exploitation of the dynamic operating functions of the NUM 1060 system, which enables the machine to maintain the original machine tool’s characteristics while allowing for improved convenience and efficiency.
2. The retention of the operating habits of the original machine, permitting operators to adjust to the transformed machine with minimum training.
3. The ability to define grinding part settings and work cycle settings on the system screen, including the number of teeth, module, pressure angle, helical angle, and teeth width, making it practical for workers to operate.
4. The use of hydraulic servo control, which makes the grinding movement extremely stable and enables the machine to operate efficiently.
5. The incorporation of a static pressure system controlled by the analog input and output ports of the NUM CNC system, which ensures the weight of the workbench remains within a certain range and prevents the floating quantity from exceeding its maximum limit.
6. The implementation of a three-level alarm system, providing reliable safety protection and automatic shutdown in the event of a defect.

Conclusion

The ZSTZ25 grinder, renovated in August 2000, has been in production for over a year and a half, working normally without any significant issues. In conclusion, the CNC transformation of the ZSTZ25 grinder has been successfully completed, revolutionizing the grinding industry and paving the way for further innovations in precision machinery.