The purpose of this document is to define a recommended practice for helping to ensure the integrity of separable reciprocating compressor applications with respect to torsional vibration. Its focus is on the practice of torsional vibration analysis and the associated assessment criteria. As required, discussions of other items related to torsional vibration inclusive of drive train design, configuration, fabrication, and assembly are also presented.
Despite the presence of more sophisticated design and analysis tools, torsional vibration‐related problems continue to be a recurring issue for reciprocating compressor installations. The majority of problems have occurred with motor‐driven compressors. However, engine‐driven systems are also not immune from experiencing torsional vibration issues. Reported problems have included crankshaft failures, coupling failures, motor shaft failures, failures of welded joints on motor spiders, auxiliary drive failures and cooler fan shaft failures. These issues often require the need to add dampers, change flywheels, change speed range, or improve tolerance of a component to the torque and the resulting stress. This document seeks to introduce some uniformity to the process of torsional vibration analysis and testing. In addition, its intent is also to provide information to those who are responsible for a compressor installation as to what to expect from a torsional vibration analysis, as well as the significance of the different elements of such an analysis.
The document’s sections are targeted as follows:
- Section 1, Scope & Introduction, provides an overview of the Guideline and its purpose.
- Section 2, General Requirements for Torsional Analysis, is most directly oriented toward those with responsibility for initiating the torsional analysis and interpreting its results.
- Section 3, Detailed Requirements for Torsional Analysis, is directed at those responsible for executing the analysis.
- Section 4, Torsional Validation Testing, provides guidelines for experimental verification of torsional behavior in the as‐built equipment.
- Section 5, Installation, Operation and Maintenance Considerations, provides guidelines for maintaining the integrity of torsionally tuned machinery systems.
- Appendix A, Data Required for Torsional Analysis, provides checklists of data required from equipment manufactures for the execution of a torsional analysis.
- Appendix B, Recommended Computational Procedures, provides specific computational procedures that have been identified as best practices for use where no other procedure has been validated for developed various subject areas referenced in the Sections 2, 3 or 4.
- Appendix C, Miscellaneous Technical Information, provides more detailed technical discussion and insight for various subject areas referenced in the Sections 2, 3 or 4.
- Appendix D, List of References, provides the references cited throughout the Guideline.
- Appendix E, Sample Reports, provides examples of detailed, comprehensive reports for engine‐driven and electric motor‐driven reciprocating compressors.