International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 07 Issue: 03 | Mar 2020 www.irjet.net p-ISSN: 2395-0072
© 2020, IRJET | Impact Factor value: 7.34 | ISO 9001:2008 Certified Journal | Page 5164
Vibration Analysis Technique for the Diagnosis of Bearing Housing
Vibrations with Different Housing Materials
Tirthak Shah
1
, Ankit Darji
2
, Divyang H Pandya
3
1
PG scholar, Dept. of Mechanical Engineering, LDRP-ITR College, Gujarat, INDIA
2
Assistant Professor, Dept. of Mechanical Engineering, LDRP-ITR College, Gujarat, INDIA
3
Professor, Dept. of Mechanical Engineering, LDRP-ITR College, Gujarat, INDIA
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Abstract - Rolling element bearings are the most common
component in all rotating machineries. There are different
types of materials are used for bearing component
manufacturing as well as bearing housing manufacturing.
This research is undertaken to study the vibrations at bearing
housing due to rotation of bearing. In this research two
different materials are taken to study the vibrations on
housing. For this research, Mild steel and Bakelite Hylam sheet
are used as housing material. This study is done at different
speeds of bearing. For this study FFT analyzer is used and
30205 healthy taper roller bearing is used. The resulting
vibration signals from FFT analyzer are processed by vibration
based techniques.
Key Words: Taper roller bearing, Vibration signature
analysis, Varying Compliance (VC), Fundamental Train
Frequency (FTF)
1. INTRODUCTION
Bearing is used to reduce the mechanical friction between
two rotating parts. There are different types of materials are
used for bearings e.g. Ceramics, Chrome steel, Plastics,
stainless steel etc. As well as, grey cast iron, cast steel,
spheroidal graphite cast iron are used for housing materials.
There are total four elements in bearing construction. 1)
Outer ring, 2) Inner ring, 3) Rolling elements, 4) cage. Outer
ring fits tightly inside bearing housing and it is not moving
part. Inner ring fits tightly on shaft, which rotates with shaft.
Rolling elements fill the gap between outer and inner ring,
which may be ball shape, needle shape, cylindrical shape
according to the type of the bearing. Cage is used to hold the
rolling elements between outer ring and inner ring and
allowing them to rotate freely. As shaft rotates, the inner ring
rotates with the shaft and the outer ring is fixed. So, the balls
start spinning inside the cage and the relative motion
between inner and outer ring is done. The contact area is
very less.
Tuncay Karacay presented a paper on Experimental
diagnostics of ball bearings using statistical and spectral
methods. In this research, brand new bearing is installed and
run throughout its lifespan under constant speed. Vibration
signatures are produced and recorded. Vibration spectra are
obtained and analyzed for defects. When the defect size
increases, vibration magnitude increases. There is no general
correlation between vibration magnitude and vibration
amplitude. (1)
Manoranjan Mahanta presented a paper on Vibration
Signature Analysis & condition monitoring of Tapered Roller
Bearing. There is a variation in the signature of the Natural
frequencies of the roller bearing with a rise in depth of
defects. By this signal, the fault frequencies can be matched
with the healthy bearing frequencies and initial faults can be
avoided by taking necessary actions before it becomes a
major defect. (2)
P.D. McFadden and J.D. Smith presented a paper on Vibration
monitoring of rolling element bearings by the high frequency
resonance technique. It is usually not useful calculating the
bearing race and structural resonant frequencies, as
calculations of the frequencies can give no level of the
relative magnitudes of the resonances which are likely to be
observed in practice. It is not possible even to be sure which
frequencies correspond to which mode of vibration. (3)
M. F. While presented a paper on Rolling Element Bearing
Vibration Transfer Characteristics: Effect of Stiffness. Roller
bearing stiffness is very nonlinear when the applied load is
small and a slight increase in load will produce a large
change in stiffness. At higher loads, the effect of the
nonlinearity is less than that for ball bearings. For a typical
configuration of bearing with relatively small clearance the
number of rolling elements present in the load zone at any
instant has an insignificant effect on the bearing nonlinear
stiffness characteristics. (4)
N. Tandon and A. Choudhary presented a paper on analytical
model for the prediction of the vibration response of rolling
element bearings due to a localized defect. The model
predicts a frequency spectrum having peaks at characteristic
defect frequencies with modulation in the case of a rolling
element defect and an inner race defect under a radial load.
The amplitudes at these frequencies are also expected for
different defect locations. The amplitude for the outer race
defect is found to be quite high with compare to the inner
race defect and the rolling element defect. The amplitude
level is also found to increase with an increase in load; and it
is affected by the shapes of the generated pulses. (5)