Vibration Measurements & Analysis
Vibration Measurements & Analyses
When severe compressor or piping line vibrations or, more drastically, piping fatigue failure or piping support unsealing occur, a vibration check is needed to assess the situation and solve the issue.
We can either provide engineers in the field, who specialize in measuring vibrations, or investigate vibration measurements made by the maintenance operators.
As a first approach to the severity of the vibrations, the measured vibrations are compared to the allowable vibration level guideline published by the EFRC (European Forum for Reciprocating Compressors) group. An assessment is carried out for each individual part of the system i.e. compressor foundation; compressor frame; cylinders; pulsation dampeners and piping lines.
When one or more parts of the compressor system are identified as unsafe for medium or long-term operation, further investigations are carried out using FFT analysis, to identify the vibrating frequencies and quantify each frequency component. When needed, bump test measurements can be performed to identify the offending mechanical natural frequencies.
Appropriate countermeasures can often be recommended immediately after these investigations. In the event that a better understanding of the vibration is needed, further calculation and investigation methods, such as pulsation and/or mechanical response analyses are used before countermeasures can be recommended.
Vibration measurement at commissioning
Vibration measurements are carried out with our light weight electronic devices including a FFT spectrum analyser and a magnetically positioned piezo-electric accelerometer. Total RMS measured vibrations are compared to the allowable vibration level guidelines published by the EFRC (European Forum for Reciprocating Compressors) group or others to be specified by client.
According to the EFRC Guidelines for “Field Survey & Commissioning”, an assessment is carried out for each individual part of the system i.e. compressor foundation; compressor frame; cylinders; pulsation dampers and piping lines.