Why is it important to use at least two compressors in a cascade system?

Using at least two compressors in a cascade system is primarily important to avoid very high compression ratios for each individual compressor. When a gas needs to be compressed significantly, attempting to achieve this large pressure increase in a single stage can lead to mechanical stress, elevated temperatures, and reduced efficiency. By distributing the compression across multiple stages, each compressor can operate within its optimal performance range, thereby preventing complications such as overheating and wear, which can occur with excessively high compression ratios.

This approach also allows for better management of heat generated during the compression process. With multiple compressors, the heat can be more effectively dissipated between stages, which enhances the overall reliability and longevity of the system. Moreover, segmenting the compression task can facilitate easier maintenance and operational flexibility.

In the context of cascade systems, the arrangement allows for tailored compression strategies, ensuring that each compressor is appropriately sized for its stage of operation. This strategy safeguards against operational inefficiencies that would arise from overly aggressive compression in a single stage and enhances the system's overall performance and reliability.