API has established standard guidelines for reciprocating compressors in API Standard 618. The current version of the standard is the Fourth Edition, adopted in June 1995. The Fifth Edition is in the process of final review and will be issued soon. EDI is a member of the API 618 sub-task force on vibration control and has been instrumental in its content.
Section 3.9 of API 618 establishes requirements for pulsation and vibration control of reciprocating compressors. Section 3.9 outlines three design approaches:
- Design Approach 1: Simplified analysis without acoustical simulation.
- Design Approach 2: Acoustical/mechanical analysis of piping system, including the use of proven acoustical suppression devices.
- Design Approach 3: Same as Design Approach 2, but including a mechanical analysis of the compressor manifold system.
Appendix M of API 618 Fourth Edition also has 11 procedures that can be used in
conducting pulsation studies. These are referred to as M.1 through M.11:
- M.1 Analytical Study: This is the same as Design Approach 1.
- M.2 Acoustical Analysis (Acoustical Simulation Study): Part of Design Approaches 2 and 3.
- M.3 Performance Analysis (Pulsation and Pressure Drop Effects): Part of Design Approaches 2 and 3.
- M.4 Mechanical Piping System Analysis: Part of Design Approaches 2 and 3.
- M.5 Compressor Manifold System Vibration and Dynamic Stress Analysis: Part of Design Approach 3.
- M.6 Compressor Manifold System Vibration and Dynamic Stress Analysis: Part of Design Approach 3.
- M.7 Piping System Dynamic Stress Analysis: Part of Design Approach 3.
- M.8 Calculation of Dynamic and Static Stresses on Pulsation Suppressor Internals: Part of Design Approach 3.
- M.9 Compressor Valve Dynamic Response Study: Part of Design Approach 3.
- M.10 Pulsation Suppression Device Low Cycle Fatigue Analysis: Part of Design Approach 3.
- M.11 Piping System Flexibility: Part of Design Approach 3.
For most systems, it is sufficient to perform procedures M.2-M.5. Depending on
the installation, procedure M.11 (thermal flexibility analysis) may also be
required. If the design procedures involved in M.2-M.5 are carried out
properly, it is EDI's experience that the additional analyses (M.6-M.10) are not
necessary. Proper application of procedures M.2-M.5 results in robust
pulsation and vibration control.
