Excessive motion by the discharge piping of a petrochemical ammonia reciprocating compressor startled the operators.  MSI was tasked with finding the root cause and suggesting a fix.


  • Problem Statement (Challenge)
    • What (type of machine): Petrochemical Ammonia Reciprocating Compressor
    • Where (State/ Country): New Jersey
    • Why (problem/reason): Operators started to notice large amounts of swaying in the discharge piping and wanted the problem investigated to prevent a potential ammonia leak.
  • Work Performed
  • Results/ Solution
    • Findings: Resonance was identified with the compressor operating speed. This was due to a discharge piping structural natural frequency.
    • Impact: The findings suggested the installation of piping supports were necessary along the length of the discharge pipe to shift the natural frequency away from the running speed. A Finite Element Analysis calibrated to the data collected on site to develop a solution with a greater chance of success upon implementation was recommended to the customer.


Locations for suggested pipe supports.



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