DODGE
B20-2
ENGINEERING
Plummer Blocks
Sleeve Bearings
SLEEVOIL
Take-Up Frames
Engineering
Part Number Index
Keyword Index
Vibration Frequencies of DODGE Anti-Friction Mounted Bearings
More and more manufacturing facilities are getting
involved with plant-wide preventive maintenance
programs. By monitoring vibration levels of motors,
pumps, fans and compressors, maintenance supervisors
can predict imminent failures. Knowing that a piece of
equipment is showing signs of potential failure permits
scheduling of maintenance at an appropriate time and
avoids the consequences of catastrophic failures. Shown
in Tables 1 - 10 are vibration frequencies generated by
bearing components defects. All frequencies are based
on unity inner ring or cone rotation.
How to Use the Tables
If a 2-7/16 Type E pillow block is rotating at 1000 RPM,
the vibration due to a failed component will show up at
the following frequencies: (Table 3, Line 6)
Frequency
Cup Nick or Spall
= 1000 x 9.251
= 9251 RPM
Cone Nick or Spall
= 1000 x 11.749
= 11749 PM
*Roller Nick or Spall
2 = = 1000 x 4.011 x8022 RPM
Cage (Train) Frequency
(Inner Ring Rotation)
= 1000 x 0.441
= 441 RPM
Since all the values in Tables 1 - 10 are based on unity
inner ring or cone rotation, the vibration due to flaws will
show up at the frequencies obtained by multiplying the
RPM times the factors found on the appropriate table.
The resulting product will have units of RPM.
Table 1:
All Setscrew, Eccentric, D-LOK & GT Ball Bearing Parameters For Vibration Analysis (1-RPS)
Series
SC
Bore
SCM
Bore
#
Balls
Diameter
of Balls
Pitch
Diameter
Outer Ring
Frequency
Hz
Inner Ring
Frequency
Hz
* Ball Spin
Frequency
Hz
Cage
Frequency
Hz
203
1/2 - 5/8
8
17/64
1.151
3.078
4.923
2.050
0.385
204
1/2 - 3/4
8
5/16
1.325
3.057
4.943
2.002
0.382
205
7/8 - 1
9
5/16
1.533
3.582
5.418
2.350
0.398
206
1-1/6 - 1-1/4
1
9
3/8
1.823
3.575
5.426
2.328
0.397
207
1-1/4 - 1-7/16
1-3/16
9
7/16
2.136
3.579
5.422
2.339
0.398
208
1-1/2 - 1-5/8
1-7/16 - 1 - 1/2
9
1/2
2.387
3.558
5.443
2.283
0.395
209
1-11/16 - 1-3/4
1-1/2
9
13/25
2.559
3.586
5.414
2.360
0.398
210
1-15/16 - 2
1-11/16 - 1-3/4
10
1/2
2.765
4.056
5.904
2.674
0.410
211
2-2-1/4
1-15/16 - 2
10
9/16
3.092
4.090
5.910
2.657
0.410
212
2-1/4 - 2-7/16
2-3/16 - 2-1/4
10
5/8
3.385
4.077
5.923
2.616
0.408
214
2-11/16
2-7/16 - 2-1/2
10
11/16
3.775
4.089
5.911
2.654
0.409
215
2-15/16
2-11/16
11
11/16
4.085
4.574
6.456
2.887
0.416
216
2-15/16 - 3
11
3/4
4.330
4.547
6.453
2.800
0.413
218
3-7/16 - 3-1/2
11
27/32
4.920
4.557
6.443
2.830
0.414