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Vibration Diagnostics
In general about machine vibration:
Like every working equipment, rotors also constitute a vibrating system, so vibration and resonance deriving from the
movement of mechanical objects goes together with their operation. Vibration can be defined as the cyclic or oscillating
movement of a machine or of one of its parts compared to the standstill position.
The degree respectively the character of these phenomena determines the condition of a machine, so it is self-evident that
we associate the condition of the machines with their vibration level. We measure the vibration level in RMS (Root Mean Square)
scale. This is the effective value of vibration speed, a square average which we obtain from the square root of the integrated
square average of the vibration speed.
Obviously it is also normal, that the machines vibrate. Even if the equipments are in their best operating condition,
they have a bit of vibration because of small insignificant deficiencies. This is why every machine has a certain vibration
level that we can regard as normal. The growth of the machines' vibration is usually caused by some kind of mechanical defect.
Without meaning to be comprehensive, these defects can be the following:
- The attrition of some of the components, first of all the bearing's wear-related fatigue
- As a result of wrong alignment the machine is steadily amortizing itself
- The component degradation deriving from the non optimal operation of the equipment.
- Rigidity or flexibility problems caused by deficient construction or foundation
As expected, all mechanical vibrations are the strongest where they emerge. The vibration's energy transfer in any
kind of material takes place with a more or less strong damping. The higher frequency the vibration is the stronger
is its damping. Consequently we can observe low frequency vibrations even from a bigger distance, but the observation
of high frequency vibrations (i.e. bearing vibrations) is quite limited.
Causes of machin vibration:
What can vibration diagnostics provide?
- It reveals the problems of deficient components or bearings in time.
- It detects the wrong alignment and it defines the misaligned element.
- It defines the proper operational parameters, detects the resultant damages.
- With the aid of the equipment's takeover analysis the inadequate construction can be excluded.
- Reflecting on the detected irregularities it shows how long can the equipment operate.
What can vibration diagnostics offer?
- Fewer unexpected defects or breakdowns (~75-95%)
- Fewer production interruption (~10-20%)
- Limited loss of components (~10-30%)
- Increasing productivity (~5-15%)
- Increasing profit (~5-10%)
- Increased maintenance efficiency (~30-50%)
The adaptability of vibration diagnostics
- Electric motors
- Air-blowers
- Pumps
- Generators
- Turbines
- Drives
- Mills
- Crushing plants
- Bruising mills
- Mixers
- Assembly lines
- Machine tools
Special application:
- Rotor balancing
- Resonance analysis
- Vibration analysis
- Accessories' detuning from their self-frequency
The usage of vibration diagnostics
- Trouble shooting analyses
- Regular, continuous sounding of the machines' condition
- Fault detecting analyses before preventive maintenance
- Control analyses after preventive maintenance
- Acceptance analysis before commissioning
The advantages of regular machine condition survey:
- Maintenance time can be increased
- The preventive maintenance is designable
- Repairs are determined by the real condition of the machine
- The condition of the equipment fleet improves
- The condition of the equipment fleet improves
Our company carries out vibration diagnostics with high performance Brüel & Kjaer 2526, Schenck Vibroport 41, és Morgan VB 2000 data collector analyzers
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