What are reasons for vibration in induction motor?
What are reasons for vibration in induction motor?
Vibration can be caused by one or more factors at any given time, the most common being imbalance, misalignment, wear and looseness. Imbalance – A “heavy spot” in a rotating component will cause vibration when the unbalanced weight rotates around the machine’s axis, creating a centrifugal force.
What is the allowable vibration limits for motor?
More stringent specifications regarding motor vibration call for maximum velocity levels of 0.1 in./sec on the housing and 1.5 mils of displacement vibration on the shaft.
What is motor vibration analysis?
Vibration analysis is a process of looking for anomalies and monitoring change from the established vibration signature of a system. The vibration of any object in motion is characterized by variations of amplitude, intensity, and frequency.
What is excessive vibration?
Vibration can cause changes in tendons, muscles, bones and joints, and can affect the nervous system. Collectively, these effects are known as Hand-Arm Vibration Syndrome (HAVS). Workers affected by HAVS commonly report: attacks of whitening (blanching) of one or more fingers when exposed to cold.
What causes vibration in physics?
Vibration, periodic back-and-forth motion of the particles of an elastic body or medium, commonly resulting when almost any physical system is displaced from its equilibrium condition and allowed to respond to the forces that tend to restore equilibrium. …
What is 1X 2X 3X vibration?
A 1X and 2X vibration signal predominant in the axial direction is generally the indicator of a misalignment between two coupled shafts. The spectrum shows high axial vibration at 1X plus some 2X and 3X with 180° phase difference across the coupling in the axial direction.
What does 1X vibration mean?
Free vibration occurs when a bell is rung or a guitar string is plucked. The most common vibration frequency is directly caused by this spinning shaft is dubbed fundamental shaft speed or running speed and is denoted as “1X vibration.”
How often should vibration analysis be done?
every month
To fulfill the data, vibration analysis should be done every month, or it may be done more frequently if the machine fails. Management allows the data collection frequencies based upon the importance, resources available at the moment, and the criticality of the issue generated.
How do you stop motor vibration?
An easy method to reduce vibration is to install a clean damper on the rear shaft of the motor. Clean dampers are basically hermetically sealed plastic cases with an inertia body packed with silicon gel. The extra inertia and silicon gel help absorb the vibration and provides a stable damping effect.
What is 1X 2X 3X in vibration?
Where to place the vibration sensor in an electric induction motor?
Figure 2: Main components of an electric induction motor with squirrel cage rotor. As we have already discussed in a general way in our article, “Where to place the vibration sensor”, in an electrical motor, the measurement points for vibrations must correspond to the centerline of the shaft, on the bearing housing.
What causes resonance in an electric induction motor?
In electric motors, resonance is usually cause by any of the following causes: 1 Operate near a critical speed or natural frequency of the system. 2 Changes in structural stiffness. 3 Speed changes that bring the motor closer to a critical speed (variable speed motors).
What causes a vibration in an electric motor?
In electric motors, bearing problems are usually caused by one of the following causes: Bad assembly, excessive preload or wear of bearing housing. Failures in the lubrication procedure, excess or deficiency of lubricant. Lubricant of poor quality or incompatible with the application. Contaminated lubricant. Excessive vibration during operation.
How is an accelerometer attached to an induction motor?
In some applications, accessories are mounted for sampling vibrations; they are devices that are attached using glue or bolts, creating a fixed and firm to place an accelerometer.