Thursday, February 12, 2009

Vibration Measurement

Writen by Elizabeth Morgan

Vibration measurement is done to create the data that's necessary in drawing a meaningful and significant conclusion from the system being tested. The said data can be very helpful in reducing as well as eliminating the vibration. Among the devices used in a typical vibration measurement system are transducers, preamplifiers, and processing and display apparatus.

The transducers are generally used in vibration measurement and analyses since they are responsible for converting mechanical energy into electrical energy. They do this by generating an electrical signal, which is a role of mechanical vibration. The velocity pickups and accelerometers installed or connected to the vibrating structure are considered transducers.

Velocity pickups generate an electrical output signal that is proportional to the velocity of the vibrating device. Since the vibrating mechanism's velocity is naturally cyclical, the sensitivity of the velocity pickup is expressed in peak milli-volts/cm/s. It is, therefore, a magnitude of the voltage created at the stage of optimum velocity. The natural frequencies of the equipment are very low, and they are tuned to calculate the vibration frequencies that are more than the pickup?s natural frequency. These velocity pick ups are considered helpful transducers since they are sensitive but strong enough to resist intense industrial atmosphere.

The accelerometer is a device that produces an output signal. The size of this electrical signal is proportional to the acceleration of the vibrating mechanism. Accelerometers possess good sensitivity qualities and a wide, helpful frequency range. Though small in size and light in weight, accelerometers are capable of calculating the vibration at a certain point without generally loading the vibrating apparatus. Moreover, accelerometers can easily work with electronic integrating networks to achieve a voltage that's proportional to displacement or velocity.

The next apparatus that's useful in vibration measurement is the preamplifier. Consisting of one or more stages, this equipment has two very significant functions. One purpose is to amplify the vibration pickup signal that's generally weak, and the other is to serve as an isolation tool or impedance transformer between the processing and display apparatus and vibration pick up tool.

The equipment intended for processing and displaying the vibration data is normally some kind of spectrum analyzer. The said analyzer can be a simple device that provides the rms equivalent of the vibration displacement, or it can be the one that essentially gives an instant analysis of the whole vibration frequency range. These analyzers are perhaps the most important device in vibration measurement. Usually, they are either a constant-percentage-bandwidth or constant-bandwidth kind of tool. They typically feature some kind of graphical display to give comprehensive frequency information.

Vibration Testing provides detailed information on Random Vibration Testing, Shock And Vibration Testing, Vibration Analysis, Vibration Control and more. Vibration Testing is affiliated with Wire EDM Machines.

1 comment:

techrentals said...

Vibration measurements is indeed an important task to do. The equipment needed to carry out such task is now available via rental service.