Analysis of Deep Grooved Ball Bearing using Solid
works
EGR 503
Mayurkumar Solanki
709426
California Baptist University
Abstract
A
3D model of a deep grooved ball bearing was developed by using Solid Works. The operating surface
of non-round profiles for the races of ball bearings developed. By varied the parameters of the
profile, it's attainable to get the load distribution on
the contact zone. During this simulation
of bearing, the amendment is found within
the stress and strain, between the inner ring, outer ring,
rolling parts and cage
of the bearing. moreover, the SolidWorks simulation
results examine the impact of
static load and impact of torsion on the inner ring of
the bearing. In this simulation two different materials accustomed examine and comparison
of the result. Alloy steel and Chrome stainless steel are used as bearing
material. This simulation studies the static analysis with the load of 500N,
1000N and 2000 N. The last part of the
paper discussed the results from the analysis of the bearing.
1.Introduction
The essential purpose of
a bearing is to decrease friction and wear among rotating parts that are in
contact with one another in any machinery. The length of time a machine will
retain its original operational efficiency and precision will depend upon the proper
assortment of bearings, the care used while installing them, proper
lubrication, and proper maintenance provided during actual operation. Ball
bearings play a crucial role in numerous machine-driven systems. The load
distribution and stiffness characteristics of the bearing can govern
performance and vibration characteristics. Performance and operating life of
the ball bearing are resolute by their internal load distribution and
stiffness. “By varying the parameters of the profile, it is possible to obtain
the load distribution on the contact zone which is the most desirable for a unit
in question” (A. orlow,1991). The operating environments of bearings in recent
machinery and devices, as well as their necessities, very important. Meeting
these requirements at a time when the rate of operation and the power strain of
mechanical systems is continually increasing, and new branches of mechanical engineering
are evolving, is becoming more and more complex. In most cases, however, the
working capability of the assembly is determined mainly by one of the basic “performances
of the bearing-frictiona1 moment, i.e. the dynamic or static load-carrying capacity,
with all the others being within tolerance.” This indicates the necessity for a
more differentiated approach to designing bearings, considering their real work
conditions and their requirement.
1.1 Bearing Parts
1.1.1
Ball and Ring
The standard material
utilized in ball-bearing rings and balls may be a vacuum-processed Iron, Steel
or high-chromium steel. Material quality for balls and bearing rings is
maintained by multiple inspections at the steel mill and upon receipt at the
bearing manufacturing plants. “The bearing steel with standard heat treatment
can be operated satisfactorily at temperatures as high as 121°C. For higher
operating temperatures, a special heat treatment is required to give
dimensional stability to the bearing parts” (Bloch & Geitner, pp.371).
1.1.2 Ball Cages
Ball cages are constrained from low-carbon steel or
alloy steel. This similar material is used for bearing shields. Molded nylon
cages are now presented for many bearing sizes. The machined cages normally provided
in super precision ball bearings are made from coated cotton fabric impregnated
with a phenolic resin. This kind of cage material has an upper-temperature
limit of 107°C with grease and 121°C with oil for extended service. (Bloch & Geitner, pp.372)
1.1.3 Lubricant
Lubricated bearings are filled with an initial
quantity of high-quality grease that is accomplished of lubricating the bearing
for years under certain working conditions. Overall, typical greases will yield
suitable performance at temperatures up to 79°C, as much as appropriate
lubrication intervals and lube quantities are distinguished. Special greases
are available for service at higher temperatures. Assessment of grease life at
high temperatures involves a complex relationship of grease type, bearing size,
speed, and load. (Bloch &
Geitner, pp.372)
2.
History of Bearing
The
precision rolling element bearing is a product of the twentieth century. It is
very simple and used for reducing friction and wear in the mechanical
equipment. The remarkable development of abundant forms of rolling element
bearings in the twentieth century but it is probable to trace the origins and
progress of these machine elements (D.
Dowson, pp.2). The basic principle of a ball bearing is if the loads are
transmitted to surface in relative motion in a mechanism the rolling elements
are interrupted between sliding members. The friction will come across by
sliding then is changed by a small amount of resistance related with rolling. (D.
Dowson, pp.3)
3. The basic steps
in the ball bearing solid works analysis
Normally basic steps in deep grooved ball bearing solid
works simulation steps involves:
1.
Define the problem
2.
Create a 3D solid
geometry model
3.
Define the
surfaces for an assembly model
4.
Define the
materials
5.
Set up elements
and boundary conditions
6.
Define and control
(fixed) the geometry
7.
Define the loads
8.
Solve problems
9.
Analyze the
results
3.1 Build finite
element model
Using solid works simulation, in theory, it is viable
that model parameters change such as material property, and applied load. This
ball bearing consists of main parts such as inner ring, outer ring, balls and,
cage. Due to different application bearing has a different kind of cages such
as seals, shield, etc. Taking the simple structure of deep groove ball bearing
into the consideration and radial loads on the inner ring of the bearing. In
this simulation two materials alloy steel and chrome stainless steel are used
as a ball bearing material. The below tables show the properties of the given
materials, and the dimensions of the ball bearing. During simulation torque of
500N, 1000N and 2000N applied to the ball bearing and finally analyze the
results.
Table 1 Material Properties
|
Bearing Parts
|
Material
|
Modulus of Elasticity (N/mm2)
|
Density(kg/m3)
|
Poisson’s Ratio
|
|
Inner Ring
|
Alloy Steel
|
2.1000
|
7700
|
0.28
|
|
Outer Ring
|
Alloy Steel
|
2.1000
|
7700
|
0.28
|
|
Rolling Element
|
Alloy Steel
|
2.1000
|
7700
|
0.28
|
Table 2 Material Properties
|
Bearing Parts
|
Material
|
Modulus of Elasticity (N/mm2)
|
Density(kg/m3)
|
Poisson’s Ratio
|
|
Inner Ring
|
Chrome stainless steel
|
2e+11
|
7800
|
0.28
|
|
Outer Ring
|
Chrome stainless steel
|
2e+11
|
7800
|
0.28
|
|
Rolling Element
|
Chrome stainless steel
|
2e+11
|
7800
|
0.28
|
Table 3 Bearing parameter
|
Parameter
|
Value (mm)
|
Modulus of Elasticity (N/mm2)
|
Value (mm)
|
Parameter name
|
Value
|
|
Bearing outside diameter
|
61
|
Rib diameter of inner ring
|
25
|
Number of balls
|
8
|
|
Rib diameter of outer ring
|
53
|
Bearing width
|
31
|
Torque
|
500 Nm
1000Nm
2000 Nm
|
|
Bearing bore diameter
|
12
|
Ball diameter
|
24
|
|
|
Figure 1 shows the finite element model of the ball
bearing. Bearing parts such as inner ring, outer ring, balls, cage and rolling
element developed using solid works and creating mesh in the geometry selecting
coarse meshing option as default. Total nodes are 14651 and elements are 8065.
Figure 1 finite element model of a deep grooved ball bearing
4. Set boundary conditions and apply load
After building a finite element model the next step is
to set up the boundary conditions and applying load to the geometry. This
analysis is going to the stress, strain and little displacement by setting up
the load. The outer surface of the bearing is fixed using a fixed geometry
option in solid works. The load is applied to the inner ring of the ball
bearing. In the first analysis, alloy steel is used as a defined material of
the bearing parts and 500 Nm torque is applied to the inner ring of the
bearing. To understand the simulation results this study analysis by applying a
different load of 1000 Nm and 2000 Nm simultaneously on the same material. This
simulation also runs using another material chrome stainless steel with the same
boundary conditions and applying the same load to the ball bearing.
5. Analyze the
results
Employing simulation, such as contact stress, stain
and displacement among the inner ring and outer ring and balls. Figure 2 shows result
of analysis with 500 Nm von Mises total stress. The biggest stress mainly
concentrated on the lower part of the inner ring. The ball and the outer ring
and rolling element experienced small amount of stress compared to inner ring. The inner ring has largest displacement which
were consistent in 500 Nm, 1000Nm and 2000Nm respectively. The biggest stress
experienced at the contact point of the inner ring and correspond to the radial
force or torsion loads. The following figures shows the all results and
comparison of the results gain from the simulation of the ball bearing.
Figure 2 von Mises stress and strain at 500Nm on inner ring (Alloy
steel)
Figure 3 von Mises stress and strain at 1000Nm on inner ring (Alloy
steel)
Figure 4 von Mises stress and strain at 2000Nm on inner ring (Alloy
steel)
Figure 5 von Mises stress and strain at 500Nm on inner ring (Chrome
stainless steel)
Figure 6 von Mises stress and strain at 1000Nm on inner ring
(Chrome stainless steel)
Figure 7 von Mises stress and strain at 1000Nm on inner ring
(Chrome stainless steel)
6. Conclusion
By means of solid works to numerically simulate and
analysis on strain and stress through deep grooved ball bearing contacts the
finite element solutions were got, which had good consistency with the Hertzian
contact stress theory. Load with 500 Nm, 1000Nm and 2000Nm examined on two
materials alloy steel and chrome stainless steel. After analyzing the results,
we can conclude that it meets all the requirements of the ball bearing design
and sustain the load with the factor of safety with 2.2. minimum yield strength
of the alloy steel material is 1.723× 108 beyond there is a chance
of the failure.
Reference
1.
Bloch &
Geitner. Machinery Component Maintenance and Repair (Fourth
Edition), 2019, pp371-447
2.
Dowson D., History
of ball bearing, vol.1 (1981)
3.
Orlow V.,
Improvement of the ball bearing wear, 48 (1991) 295-304
4.
Tang Z & Sun
J., The Contact Analysis for Deep Groove Ball Bearing Based on ANSYS, 23 (2011)
423 – 428
