Large compressor shaft rotor design: performance guarantee behind precision and complexity

In large compressor systems, the shaft rotor is the core component of power transmission and energy conversion. Its structural design not only determines the performance of the compressor, but also directly affects the stability and reliability of the entire system. The structural design of the large compressor shaft rotor is so precise and complex, mainly because it needs to meet a variety of harsh operating conditions and performance requirements.

When the large compressor shaft rotor rotates at high speed, it will generate huge centrifugal force and vibration. In order to ensure that the rotor remains stable during long-term operation, its structural design must fully consider dynamic balance. This includes accurately calculating the mass distribution of the rotor, optimizing the layout of components such as the impeller and balance disk, and using advanced dynamic balancing test technology to ensure that the rotor can achieve a good balance state at any speed. In addition, the support structure of the rotor, such as rolling bearings or squeeze film bearings, also needs to be carefully designed to withstand huge radial and axial loads and reduce vibration and noise.

During the operation of a large compressor, the heat generated by gas compression and the heat generated by mechanical friction will cause the shaft rotor to be subjected to significant thermal stress. At the same time, the difference in thermal expansion coefficients between different materials will also cause stress concentration inside the shaft system. The structural design of the shaft rotor must consider the distribution and mitigation measures of thermal stress, such as adopting a reasonable thermal expansion compensation structure to ensure the stable operation of the shaft system under different working conditions.

In rotating machinery such as turbines and compressors, the interaction between fluid and solid structure (i.e., fluid-solid coupling effect) is an issue that cannot be ignored. During the operation of large compressor shaft rotors, they will be affected by gas elastic force, leading to vibration instability and other problems. In the structural design, a detailed fluid-solid coupling analysis is required to evaluate the influence of gas elastic force on rotor stability, and take corresponding design measures, such as optimizing the impeller shape and adjusting the gap size, to improve the rotor's anti-instability ability.

Large compressors often need to operate under a variety of working conditions, such as starting, stopping, and variable load. These working condition changes will have different effects on the shaft rotor, such as transient response, coupled torsional vibration, pulsating torque, etc. Therefore, in the structural design, it is necessary to fully consider the adaptability of the rotor to multiple working conditions, and reduce the influence of working condition changes on rotor stability through reasonable structural design, such as using flexible couplings and setting up shock absorbers. At the same time, reliability design is also required, such as adopting redundant design and setting up monitoring systems to improve the operating reliability and safety of the rotor.

The structural design of the large compressor shaft rotor also needs to consider the requirements of manufacturing process and assembly accuracy. Complex structural design often means higher processing difficulty and assembly requirements. In the design process, it is necessary to closely integrate with the manufacturing process, adopt advanced processing technology and assembly technology to ensure the manufacturing accuracy and assembly quality of the rotor. At the same time, the interchangeability and maintainability of parts must also be considered to facilitate subsequent maintenance and troubleshooting.

The structural design of the large compressor shaft rotor is a precise and complex system engineering. It needs to comprehensively consider multiple factors such as dynamic balance, thermal stress management, fluid-solid coupling effect, multi-condition adaptability, manufacturing process and assembly accuracy. Through scientific design methods and advanced technical means, a large compressor shaft rotor with performance, stability and reliability can be designed to provide a strong guarantee for the continuity and efficiency of industrial production.