Rewheeling Centrifugal Compressors: Design Considerations and Field Application
Centrifugal compressors are commonly used for high flow pipeline applications with well defined operating conditions. Centrifugal impellers are selected based on their ability to meet a variety of expected operating conditions. As market and pipeline conditions change over time, these compressors may operate at poor efficiencies (near surge or stonewall conditions). To better meet current and future operating conditions, the compressor performance can be modified and improved by selecting and installing a better matched impeller wheel. This technical paper and case study discuss two issues related to rewheeling a centrifugal compressor. The first part of the paper will discuss the criteria that users should consider when determining whether or not a compressor rewheel is merited and justified. This section will also include a discussion about upgrades and enhancements that are commonly selected (acoustical arrays, dry gas seals, modern surge control, etc.). The second part of the paper discusses field application and installation considerations that should be considered when upgrading an existing centrifugal compressor (including a case study). This technical paper is co-authored and presented by OEM and pipeline company personnel to provide a well-rounded approach and discussion of considerations and factors that are important to the overall success of a compressor rewheel.