Sucess Case: Motor Unbalance

A new sucess case. Dynamox develops an innovative solution for industrial maintenance: a wireless vibration and temperature meter, with Application, Web Platform and Gateway (automatic collector), with the objective of monitoring the health of critical equipment.

Following in our series of success cases, the company AAM, manufacturer of parts for the automotive sector, recently identified an unbalance in a motor that feeds the fan of one of the heat treatment furnaces in the plant of Curitiba – PR.

The meter allows data collection with frequency from 1 to 60 minutes, allowing adjustment according to the criticality of the equipment.

In this case, samples of global levels of vibration and temperature are acquired every 20 minutes, a choice made by the AAM maintenance team. The following table shows the configurations of the meter in use.

Monitoring configurations of the sensor used at the measuring point

With the aid of spectral analysis, which the Dynamox meter itself carries out, it was detected that the motor already presented unbalance when the device was installed, as can be seen in the figure below, taken from our Web Platform:

Spectral analysis in terms of speed in the horizontal direction during unbalancing.

The figure shows a high level of vibration at the machine’s rotational frequency (3600 RPM or 60Hz) in the horizontal direction, especially when the spectrum is analysed in the speed parameter. These are precisely characteristics of axis unbalance.

After the identification of this problem, an attempt of balancing in loco without disassembling the motor was performed, however, as will be visible in the global vibration levels graph below, the intervention did not present the expected result and even caused a substantial increase in vibration levels:

RMS continuous speed monitoring graph evidencing elevation in vibration levels after unsuccessful balancing attempt.

The next operation consisted in the removal of the fan motor for revision and balancing in laboratory / workshop, period in which, naturally, the sensor measured practically null levels of vibration:

RMS continuous speed monitoring chart evidencing zero vibration levels after engine shutdown

After the proper balancing of the engine, the sensor started measuring vibration levels around 5 times lower, proving precisely the good maintenance work done on the equipment.

Continuous RMS speed monitoring chart showing vibration levels reduction after proper balancing

This can be seen not only in the continuous monitoring, but also in the spectral analysis, where it can be observed a drop of approximately 80% in the vibration amplitude in the motor operation frequency (1X):

Spectral analysis in terms of speed in the horizontal direction after well-executed balancing

This success story shows the many facets of the solution, which allows:

Detect faults in a predictive manner, avoiding the high costs of corrective maintenance and machine downtime;

Perform maintenance interventions at opportune moments, when the machine actually presents problems, even allowing scheduling shutdowns, if necessary;

Check the maintenance work done, pointing out if the problem was really solved;

Perform a record of occurrences at the monitored point using our “timeline” tool, which allows annotations to be made on graphs, thus creating a detailed history of events.

Bring this assertiveness and control to your company’s maintenance. Learn more about the product on our website.