Vibration related consultation, analysis & machine diagnostics, as well as comprehensive testing of vibration measurement systems


  • Examination of the running system, consideration of vibration problems, revision recommendations, testing of spare parts
  • At the beginning of revision: static and dynamic testing of the complete loop, exchange of defect components, report on diagnostic findings
  • Conversion to reverse mount probes in kmo probe holders
  • Renewal of discontinued monitor systems
  • Replacement of discontinued monitors by transmitter solutions
  • Quick repair of probe cable (particularly damaged plug connections)
  • Toward the end of revision: Installation and setting of the probes, loop checks, start-up of the monitoring system
  • Final report with characteristic curves, determinations, recommendations
  • Realization of permanent vibration analyses
  • Professional support for machine diagnostics

Operational faults announce themselves!

Problems with the bearings, with the alignment, with the balancing condition, with the sealing, … almost every operating problem announces itself as soon as it develops; at the earliest and most distinctly through a change in the vibration behavior. The rotor vibration is the most important monitoring criterion for an effectively preventive maintenance of turbomachinery. Hence, those responsible for operations are well-advised to ensure that the monitoring system is subject to regular checks and servicing.

Better check your vibration measurement systems!

Temperature-, pressure- and flow measurement circuits are checked at regular intervals, at the latest during each revision. Shaft vibration measurements (non-contact displacement measurement according to the eddy current principle) are particularly failure-prone, but experience has shown that they are hardly ever subject to servicing. Most operators are content with simply setting the GAP signal at 9 V. Neither loop sensitivity, limit values nor indicators are usually subject to checks, although correct vibration values present an extremely high level of information content; whereas false indications can quite easily lead to disastrous misinterpretations.

That it is not sufficient to merely set the GAP distance at 9 V is clearly shown by the fact that regardless from the manufacturer from approx. 400 loops that were initially correctly set, almost 20% demonstrated deficiencies during tests.

We have compiled a list showing a selection of the determined deficiencies, some of which have produced disastrous effects (read on …)

General recommendations:

  • Keep a sufficient amount of spare parts at hand! Determined deficiencies (e.g. due to incorrect operation) cannot be remedied immediately if exchange components are not available.
  • The vibration measuring device should be checked and a comprehensive report should be compiled both as soon as new commissioning is performed and regularly thereafter, at least before and after each revision!
  • Carry out regular frequency analyses and file the results. The major information content for the diagnosis is not found in the absolute values, but in the actual changes.
  • Extensive vibration analyses performed with sophisticated diagnostic systems sometimes fail due to the fact that a sufficiently intensified raw signal is not provided. In the case of transmitter systems, 2-wire transmitters are often used; in addition to numerous advantages, these also present the disadvantage that the buffered output is not sufficiently intensified, i.e. the cable length between the analyzer and the oscillator is not allowed to exceed a maximum of 3 meters, which means that the use of multi-channel diagnostic systems is only possible to a limited extent. With the aid of the module PT375, we are able to remedy this problem and intensify the signal so that a cable length of up to 300 meters is possible.