A jaguar (SKF) bearing
The main purpose of this experiment was to develop a practical application in which the ‘health’ of SKF Jaguar bearings was tested using vibration condition monitoring (VCM). When bearing is not in healthy condition, loud noise, high temperature, vibration and harshness (NVH) on bearing housing will appear. So, the measurement and monitoring of vibration or harsh noise in machinery can be used to detect faults and assess the condition of moving or rotating components. The main interest was to evaluate the effectiveness of VCM techniques in analysing bearing faults in SKF Jaguar hub assemblies.
Aim and Objective
The aims of this experiment were:
* To investigate spectrum analysis methods to analysis vibration in SKF Jaguar bearing.
* To carry out test to identify the sources of noise, vibration and harshness in SKF Jaguar bearing.
The objectives of this experiment were:
* To complete test to acquire a practical knowledge of new and used bearing performance and method of condition monitoring of bearing to predict failure.
* To analyses the health level of a bearing in rotating machinery through noise (dB level) vibration monitoring methods.
* To give recommendation for improve test equipments and procedures for identifying specified in SKF Jaguar bearing.
The motor drove the SKF Jaguar bearing which was installed in the fabricated hub, and using the inverter to control and adjust the rotational running speed of the electric motor. Consequently, spectrum analysis was performed using the accelerometer to place on the hub and measure the driveshaft rotational frequency, as depicted in figure 1.
First of all, the machine was run at frequency of 20 Hz with the accelerometer which placed on the top of the hub. However, the readings which point with various measurements on the spectrum analyser, and the running frequency were then decreased to 18 Hz due to slippage. For further testing, the sine wave indicator using a stress wave instrument to check for faults on the SKF Jaguar bearing. Last but not least, the sound level meter was used at 1m to measure A-weighted background and target noise levels during SKF Jaguar hub unit tests. This can be seen in figure 2 and figure 3.
Figure 2: The frequencies reading are monitored on the spectrum analyser.
From the graph above shows that the peaks which are present after the test are main three, the rolling element defect frequencies, outer race frequencies and inner race frequencies. The further testing which check the distress reading using the stress wave instrument to check for faults on the bearing hub. The tests was performed at 20 Hz running frequencies and get the noise overall result around 77dB-78.7dB. The dynamic condition result obtained from the test is within limits of 85dB.
Figure 3: Take a noise measurement using octave band analysis at 1m.
According to the figure 3, the noise levels test using octave band analysis was performed and the overall of the noise levels was 82.4dBA. The overall result shows that the noise compliance with the standard limits which is below 85dBA.
The tests on the SKF Jaguar bearing have been performed and the results are obtained. From the result it is evident that the noise compliance with the standard limits which is below 85dB. While achieving the result the frequency spectrum analysis technique was learned. This method accurately measure the vibration produced on the SKF Jaguar bearing.