everything that rotates
                        needs to be balanced


XYO Balancer Blog  RSS

Vibration Information for rotating machinery applications.


Imbalance in Overhung Machinery

Wednesday, June 13, 2012

An overhung machine is one where the fan or impeller lies outside of the bearings that support the shaft. Figure 1, below, shows an illustration of an overhung impeller. Read More

Types of Belt Drives

Friday, March 23, 2012

Belt drives are widely used in many industries for power transmission since they are cheap and easy to maintain. However they are often a source of vibration due to misalignments, belt resonance, and belt wear.  Read More

Acceptable Levels of Vibration

Friday, March 16, 2012

It is essential to design a device that has to meet a certain vibration level. Ideally, the desired vibration response must be clearly stated before a design can begin. Many different methods have been proposed to measure and describe acceptable levels of vibration in many different areas including building structures, power tools, cars. Vibration measurement should be established in terms of displacement, velocity, or acceleration, and how a device should be measured needs to be clarified. These measurement selections often depend on the specific application. It is generally accepted that the best indication of potential machinery damage is the amplitude of the machinery’s vibration velocity. Acceleration amplitude is the most perceptible by humans, for example acceptable level of vibration in angle grinders is 2.5m/s2 for 8 hour use. Some common ranges of vibration frequency and displacement are given in Table. Read More

Electric Motors: Dynamic/Online Testing

Friday, March 09, 2012

In a previous post I discussed electric motor testing, specifically static or offline testing. This week I would like to tackle the subject of dynamic or online testing of electric motors. Read More

Vibration Suppression: Active and Passive Systems

Thursday, March 01, 2012

Machines are expected to vibrate as little as possible to avoid component fatigue/failure and in some cases, reduce user comfort level, for example, violent vibration of an automobile can lead to mechanical failure and driver discomfort. There are ways to avoid violent vibration such as running the machine away from critical speeds and suppressing vibration using active system or passive system. The latter can be implemented during design stage. Vibration problems are often found late in the process after a product is designed, prototyped, and tested, thus design changes are often needed. Read More