NASA Contractor Report 3381 

Roller Skewing Measurements 

in Cylindrical Roller Bearings 

Lester J. Nypan 

GRANT NSG-3065 

JANUARY 1981 
NASA Contractor Report 3381 

Roller Skewing Measurements 

in Cylindrical Roller Bearings 

‘1 

Lester J. Nypan 

Ca Ziforrzia State University, Nortbridge 

Northridge, Califorizia 

Prepared for 

Lewis Research Center 

under Grant NSG-3065 

nmsn 

National Aeronautics 

and Space Administration 

Scientific and Technical 

Information Branch 

1981 

. ---- 

Table of Contents 

Summary 

Introduction 

Test Bearings 

Lubrication 

Method of Approach 

Film Measurement and Error Estimation 

Load and Bearing Misalignment 

Test Program and Data Organization 

Results and Discussion 

Conclusion 

References 

Page 

1 

2 

3 

3 

3 

5 

6 

7 

7 

12 

13 

iii 
Summary 

Measurements of,roller skewing ina 118 mm bore roller 

bearing operating at shaft speeds to 12000 rpm are reported. 

High speed motion pictures of a modified roller were 

taken through a derotation prism to record skewing as the 

roller moved through loaded and unloaded regions of the 

bearing. Subsequent frame by frame measurement of the 

photographic film provided information on roller skewing. 

Radial and tangential skew amplitudes of .4 to .5 degrees 

were observed with .5 degree misalignment. 
Introduction 

Rollers in roller bearings may misalign or skew as they 

roll between the raceways (l>l. This is controlled by small 

clearances between race shoulders and the roller which provide 

a restoring moment at the ends of the roller to restrain the 

roller from further skewing. In high speed turbine bearings 

the skewing and associated rubbing contact can lead to wear 

on the roller ends, increased skewing, and eventual failure (2). 

In some instances skewing and wear can be so severe that the 

roller turns and lodges within the separator pocket (3). 

This investigation was undertaken to gather experimental 

data for comparison with theoretical predictions of skewing 

magnitudes, and also for comparison of one roller bearing 

design with future improved designs. The investigation reports skewing behavior of a 1.15 length to diameter ratio 

roller in 118 mm bore roller bearings of 0.18 and 0.21 mm 

(0.0073 and 0.0083 in.) clearance operating with a 4450 N 

(1000 lb) radial load at shaft speeds of 4000, 8000, and 12000 

rpm with outer race misalignment of 0, 0.25, 0.5, -0.5 degree. 

----- 

1 Numbers in brackets designate References at end of paper. 

2 
Test Bearings 

Two test bearings were used in the investigation. They 

were representative of aircraft gas turbine engine roller 

bearings and had-PWA'541043D markings. The bearings' original 

Out-Of-POUnd outer rings were replaced ,with cylindrical rings having radial clearances of 0.18 and 0.21 & 

(0.0073 and 0.0083 in). These radial clearances were calculated as the difference between the average of the outer 

race measured maximum and minimum inner diameters and the 

inner race nominal raceway diameter plus two roller diameters. 

Table I gives dimensions of the bearings used. 

Lubrication 

While the inner race had grooves for under race cooling 

and drilled passages for cage and roller lubrication, these 

were not used. Oil was sprayed onto the rollers through two 

.jet pipes at a total flow rate of 1.8 x lo -3 m3/min (0 . 47 gpm) . 

The oil used was a 5-centistoke neopentylpolyol 

(tetra) ester. This is a type II oil which conforms to specification MIL-L-23699. Test bearing inlet oil was heated and 

controlled to 339OK (15OOF). 

Method of Approach 

Roller skewing was measured from photographs of a 

modified roller in a bearing operating at shaft speeds to 

12000 rpm. Figure la is a schematic of the test shaft 

assembly. A 16 mm Fastax WF4 camera was used with synchronized Xenon flash tube illumination to photograph a 32 x 24 mm 

(1.25 x .94 in) area of the bearing at up to 8000 frames per 

second. The derotation prism apparatus described in ref. 

(4-7) was used to maintain this area centered on the 

modified roller and to follow this roller as it orbited 

through 360 degrees within the bearing. The 

3 
32 x 24 mm (1.25 x -94 in) area photographed in 16 mm format 

included a segment of a fixed outer race protractor, a segment of-an inner race protractor, a segment of the rolle,r 

bearing separator, the modified roller and portions of adjacent rollers. Figure lb is an enlargement of a data photograph. At the 12000 rpm shaft speed photographs of the modified roller were obtained at 4 'to 5 degree intervals as observed on the outer race protractor. The inner race protractor permitted cage to shaft speed ratio determinations. 

Two to three hundred photographs could usually be obtained 

before the energy storage capacitors discharged. This permitted photographs of three to four revolutions of the separator and roller orbit to be obtained. 

Camera speeds of 6000 frames per second were often used 

for the 8000 and 4000 rpm bearing speeds with proportionate 

adjustments to photographic intervals within the bearing and 

number of separator revolutions available for analysis. 

The roller modification to permit frame by frame roller 

orientation measurements incorporated a 3.18 mm (0.125 in) . 

diameter x 1.59 mm (0.626 in) deep counterbore recess to 

help to identify the roller center in the photographs. A pin 

1.27 mm (0.050 in) in diameter by 6.35 mm (0.250 in) in length 

is extended out along the roller axis from the roller end. 

Fzlgure 2 is a photograph of a modified roller. 

In the data photographs, the end of the pin appeared 

superimposed on the image of the counterbore. By measuring 

radial and tangential distances from the counterbore image 

center to the pin image center and dividing by the pin 

length the tangents of the roller orientation angles are 

obtained. Measurements were made so that the roller orientation 

angles are radially outward from the bearing center and tangent 

to the roller path. As the camera axis was oriented along the 

bearing center line the pin image center is always offset 

radially on the counterbore image by the "camera angle". 

The radial roller skew angle appears superimposed on the 

constant camera angle. Radial and tangential roller skew 

4 
angles are thus obtained as a function of roller location 

within the bearing. 

Film Measurement and Error Estimation 

A Vanguard Instrument Corporation Motion Analyzer 

was used to project the films for frame by frame measurement. A template with concentric circles was used to align 

a Gerber Scientific Instruments measuring and digitizing 

instrument first on the image of the pin end, and then on the 

image of the counterbore. Four digit measurements of the tangential and radial coordinates of the circle centers were 

automatically punched on computer cards at each alignment. 

A computer program calculated differences, applied scale 

factors and prepared output to drive a Calcomp 936 plotter 

to graph the data. 

An estimate of the uncertainty and possible errors 

inherent in the measurement system was obtained by repeatedly 

measuring the same film frame. These measurements were 

then processed in the same manner as regular data measurements made on frames taken at 5 degree increments of roller 

orbit within the bearing. Figure 3 shows the apparent 

variation in skew angles due solely to the film measurement 

system. The test indicates that the maximum deviation 

from the mean of 72 readings was 0.42 degrees. The standard 

deviation from the mean was 0.028 degrees in radial skew 

and 0.037 degrees in tangential skew. When the test measurements were subjected to the Fourier analysis described under 

Results and Discussion, Figure 3F resulted. It may be observed that amplitudes of up too.12 degrees are.present. 

The limitations of the measurement system should be considered in evaluating the tioller skew data presented in this 

report. 

5 
A 4450 N (1000 lb) load was used throughout most of the 

investigation. This was applied to the test bearing by acabie 

loop over the test beardng as may be seen in Fig. la. The outer 

race protractor was positioned so that 0 (360) degrees was 

centered under the cable loop. As the derotation prism and 

camera viewed the protractors and bearing the protractor degree 

scale increased in a clockwise direction, Due to bearing 

clearance rollers entered the loaded zone at about 3400 

and left it at about 20°. 

The misalignment of the outer race relative to the inner 

race was measured with a dial indicator on a bar bolted to the 

end of the test shaft. The bar was perpendicular to the 

shaft center line. Measurements were made by indicating 

on a machined surface of the test bearing housing. This 

machined surface of the housing was also perpendicular to the 

shaft center line when the zero misalignment cases were set 

up* What is referred to as positive misalignment in this 

report was produced by forcing the housing at 900 towards 

the prism and camera while simultaneously forcing thehousing at 270° away from the prism and camera by 

turning nuts on studs extending from the test machine frame. 

Back-up nuts were kept tight to keep the housing positively 

positioned. The shaft was turned over by hand and indicator 

readings writtencbwn at 45' intervals over a shaft revolution. 

Nuts forcing misalignment and back-up nuts were readjusted until 

the desired misalignment condition was attained. Negative 

misalignment was produced in a similar fashion by using the 

nuts and studs at 90° and 210' to force the 90' housing 

location away from the prism and camera while forcing the 

270° housing location towards the prism and camera. 

By adjusting the nuts constraining the housing at 90 

and 270 degrees the outer race was pivoted about an axis 

through 0 and 180 degrees on the outer race protractor. 

Misalignment was maximum at 90 and 270 degrees and minimum 

at 0 and 180 degrees. Rollers entered the loaded zone at 

6 
about 340 degrees with the misalignment decreasing, passed 

the most heavily loaded point at 0 degrees with the raceway 

surfaces most nearly parallel, and exited with roller to 

raceway contact force decreasing as the roller encountered 

increasingly non-parallel raceway surfaces. 

While it‘had originally been proposed to study misalignment of 0, 0.25 and 0.50 degrees, a reversed misalignment of -0.50 degrees was added to the test program 

to determine the effect of a reversal of misalignment on 

roller skewing behavior and the measurement system. 

Test Program and Data Organization 

The chronological sequence of tests may be followed 

through the dates and film sequence numbers identifying films 

and data obtained from the films. Testing began with the 

0.21 mm (0.0083 in.) clearance bearing with 0 degree misalignment with films being taken at 4000, 8000, and 12,000 

rpm under the 4,450 N (1,000 lb) load. TaIIe 2 lists data 

presented in the report, and summarizes the organization and 

figure identification system for the bearing clearance, 

misalignment, and speed cases studied. 

As indicated in Table 2, Figures 4 through‘7 are results 

obtained with the 0.18 mm (0.0073 in.) clearance bearing. 

Figures 4a, b, c are data at 0 degree misalignment and 

4000, 8000, and 12,000 rpm. Figures 5a, b, c; 6a, b, c; 

and 7a, b, c are results at 0.25, 0.50, and -0.50 misalignment. As more than one roller orbit or revolution of the 

roller‘through the bearing could sometimes be read from 

the film taken for each of these figures a further number is 

added as 5b-1, 5b-2, to identify the revolution or reading 

of the film. Figures 8 through 11 show similar information 

for the 0.21 mm (0.0083 in.) clearance bearing. 

Results and Discussion 

To plot radial and tangential roller skew angle simultaneously on the same axes without overlap, the camera angle 

7 
- I 

of about 4.7 degrees was plotted along with the radial 

skew angle. The camera angle appears in the data photographs because the roller center is radially distant 

from the bearing-camera center line by the bearing pitch radius. 

Radial roller skew motions are superimposed.on the camera angle. 

A fast Fourier transform (FFT) program was used to 

estimate the frequency components of the data. The FFT 

program requixs N equally spaced data points and N must be a power 

of 2. These data points were obtained by linearly interpolating 128 points over the 360 degrees of roller orbit 

measured in each film. Plots of tangential and radial skew 

angle amplitude absolute value (degrees) as a function of 

frequency are presented on pages facing the original data 

figures and are numbered with the original figure number 

followed by F. Phase (degrees) is also plotted. 

Output from the FFT program was manipulated so that the 

amplitudes are the square root of the sum of the squares of the 

ai and bi coefficients of the Fourier series sine and cosine 

terms for each frequency.The phase angles are the arc tangent 

of the ai/bi coefficients. Fourier analysis figures are 

plotted so the first amplitude is the average value of the 

data in the original figure, the second amplitude is the 

amplitude of a sine function of 360 degree roller orbit 

period, the third amplitude is the amplitude of a sinusoid 

of two cycles in the 360 degrees of roller orbit, etc. 

The average value of the radial skew data includes the 

camera angle. In order tcmake this point plot together 

with the other roller skew amplitudes of 0.4 degree or less, 

this first point was plotted at a tenth of its true value so 

that the first radial skew amplitude plotted at 0.47 degrees 

indicates an average radial skew plus camera angle of 4.7 

degrees. 

Figure 4a shows a result obtained with the 0.18 mm 

(0.0073 in.) clearance bearing at O" misalignment and 

4000 rpm. It was plotted from 202 frames taken every 

8 
1.8 degrees of roller position within its orbit. While 

any reading could be in error by as much as 0.4 degrees, 

the errors are probably of the order of 0.04 degrees as 

indicated in the paragraphs on Film Measurement and Error 

Bstimate. An average skew angle is evidently,present along 

with amplitudes associated with a number of frequencies. 

Figure 4a and 4aF together indicate a tangential skew, 

averaging -0.33O over the roller orbit, a one-cycle-perorbit skew amplitude of O.O5O, a 2-cycle-per-orbit skew 

amplitude of O.O2O, a 3-cycle-per-orbit skew amplitude of 

0.050, a 4-cycle-per-orbit skew amplitude of O.l3O, an 

8-cycle-per-orbit skew amplitude of 0.08', and a 12-cycle-perorbit skew amplitude of 0.28O. The radial skew plots indicate 

a camera angle plus.average radial skew angle of 10 times 

0.47 or 4.7O; 2, 3, 4, and 12-cycle-per-orbit amplitudes 

of 0.04, 0.03, 0.02, and 0.31'. In view of the 0.12O 

amplitude noted in repeated measurements on the same film 

frame described under Film Measurement and Error Estimation 

amplitudes less than 0.12 may not be significant. 

The 12-cycle-per-roller-orbit frequency which appears 

strongly in all the data corresponds to the roller frequency as the ratio of outer raceway circumference to roller 

circumference is 12.42. This is the roller to cage speed 

ratio. This investigator has not been able to make use of 

information in the phase angle data. 

Figures 4b, and 4c show the effect of increasing speed 

at O" misalignment. The amplitude at 4 cycles per orbit 

continues to be evident in the tangential skew, and the 

sharp peak at 12 cycles that was evident in Figure 4a broadens 

to include 11 and 14 cycles. 

Figures 5a, 5b-1, 5b-2, 5c-1, and 5c-2 are results 

at 0.25O misalignment. A radial skew amplitude of about 

0.18O with a l-cycle-per-roller-orbit frequency is evident 

in all of these Figures. Figures 5b-1, 5b-2,,5c-1 and 5c-2 

show differences in consecutive revolutions. The amplitude 

associated with the roller frequency is up to 0.39O in 

9 
Figure 5a and extends from 11 to 15 cycles-per-roller-orbit 

with smaller amplitude in Fig. 5c-2. 

Figures 6a, 6b, 6b-2, 6c-1, 6c-2, and 6c-3 show results 

with the bearing misaligned by 0.5O. The radial skew 

amplitude is 0.33 to 0.430 at one cycle per orbit. The 

original data plots resemble a negative sine function. 

Radial and tangential skew amplitudes associated with the 

roller frequency again appear to broaden in frequency extent 

as speed increases. It was not possible to read data beyond 

3200 in the second roller orbit for Fig. 6b-2, and a Fourier 

analysis was not obtained for this figure. Some lower frequency components appear.consistently in the 3 roller orbits 

through the bearing that are followed through Figures 6c-1, 

-2, and -3. 

Figures 7a-1, 7a-2, 7b-1, 7b-2, 7c-1, and 7c-2 show the 

result of a reversed misalignment of 0.5O. Radial skew amplitude are typically 0.470 at one cycle per orbit, and the 

original data plots resemble a positive sine function of one 

period per orbit. Comparing this one cycle per orbit information with the one cycleperorbit radial skew information in 

Figures 5 and 6, it seems that the one cycle per orbit radial 

skew is the misalignment of the outer race which is being 

followed by the roller. A noticeable amplitude in both radial 

and tangential skew at 4 cycles per orbit is present in a 

number of these figures. It was possible to follow 2 orbits 

at each of the 8000 and 12,000 rpm speed cases. There appear 

to be differences in roller behavior from orbit to orbit. 

Successive revolutions in Figure i'a-1 and 7a-2 differ as the 

amplitude of one cycle per orbit radial skew is more apparent 

in Figure i'a-2. As the outer ring circumference is not an 

integer multiple of the roller circumference, the roller may 

not enter the loaded zone with the same skew angles on successive 

revolutions. 

Figure 8a, 8b, and 8c show results for the 0.21 mm 

(0.0083 in.) clearance bearing with Oo misalignment at 

the 4000, 8000, and 12,000 rpm speeds. There appears to be 

no significant amplitude at low frequencies, but a skewing 

amplitude of 0.19 to 0.26O at the 12 cycle per roller orbit 

frequency. 

10 
Figures 9a, 9b, and 9c show results for the larger 

clearance bearing with 0.25O misalignment. There is radial 

skew amplitude of 0.1 to 0.230 at one-cycle-per-roller 

orbit. Both tangential and radial skew amplitudes of 0.18 

to 0.26O are present at the 12 cycles-per-roller orbit 

frequency. Some broadening of the 12 cycle appears as 

speed increases. 

Figures lOa, lob-l, lob-2, lOc-1, lOc-2, lOc-3, and 

lOc-4 show the effect of 0.5O misalignment. A one-cycleper-orbit amplitude ranging from 0.18 to 0.45O is present 

in radial skew angle with the original data again resembling 

minus sine function. A 12-cycle-per-orbit amplitude ranging 

from 0.12 to 0.36O is present. The 4000 rpm speed case has 

the highest amplitude and most sharply defined 12 cycle 

frequency. As speed increases the 12 cycle amplitude seems 

to decrease, and broadens to extend to lower frequencies. 

Figures lob-1 and lob-2 at 8000 rpm show some variation in 

consecutive revolutions. Figures lOc-1, lOc-2, lOc-3,1Oc-4, 

lOc-5, and lOc-6 at 12,000 rpm further indicate differences 

from revolution to revolution. 

Figures Ila, lib-1, lib-2, Ilc-1, llc-2, and llc-3 show 

the result of a reversal of the 0.5O misalignment. Radial 

skew amplitudes of 0.39 to 0.55O appear at one-cycle-perroller orbit with the original data again resembling a 

positive sine function. Tangential and radial skew amplitudes of 0.12 to 0.32O appear to be associated with the roller 

frequency. Figure lla appears to indicate there may be a 

tangential and radial skew amplitude of 0.12O at 20-to 24- 

cycle-per-roller orbit frequency. This may be a 2 times 

a roller revolution skewing behavior that could be seen only 

in 4000 rpm speed studies as the camera frame rate gives 

data at about 2, 4, and 6 degrees of roller orbit at 4000, 

8000, and 12,000 rpm shaft speeds. This limits the frequencies 

11 
observable in the data. This frequency does not appear 

as prominently in other 4000 rpm speed cases. Data from 

consecutive revolutions again appears to differ slightly. 

Figures llc-2, and llc-3 show the effect of missing frames 

over 90 to 16D" of roller orbit. The film was not measureable 

over this sector of the bearing, but could provide information 

over the rest of the roller orbit. The missing frames are 

interpolated as a straight line in the FFT program which 

makes the frequency analysis information difficult to 

evaluate. 

Conclusion 

Radial skew amplitudes of 0.4 to 0.5O at the roller orbit 

frequency were observed with 0.5O bearing misalignment. Radial 

and tangential skew amplitudes of 0.4O associated with the 

roller frequency were observed. These generally decreased 

in amplitude and extended in frequency at higher speeds. 

The 0.21 mm (0.0083 in.) larger clearance bearing general1.y 

had slightly smaller roller skew amplitudes than the 

0.18 i (0.0073 in.) clearance bearing. Differences in roller 

skewing are apparent in successive orbits of the roller. 

Further work which should be undertaken is the investigation of roller skewing with misalignment oriented so that 

the loaded zone of the bearing includes raceway surfaces 

of maximum misalignment. 

12 
I - - 

References 

1. Savage, M. and Loewenthal, S.H., "Kinematic Stability 

of Roller Pairs in Free-Rolling Contact", NASA Technical 

Note ~-8146, 1976. 

2. Savage, M. andPinkston,B.H., "Roller Bearing Geometry 

Design", NASA CR-135082, October 1976. 

3. Greby, D.F., "What Turbine Technology Is Teaching Us 

About High-Speed Roller Bearings", Machine Design, 

April 30, 1970, pp 229-234. 

4. Signer, H.R., "Experimental Ball Bearing Dynamics Study", 

NASA CR-134528, October 1973. 

5. Nypan, L.J., "Ball to Separator Contact Forces in Angular 

Contact Ball Bearings Under Thrust and Radial Loads", 

NASA CR-2976, April 1978. 

6. Nypan, L.J., "Roller to Separator Contact Forces and Cage 

to Shaft Speed Ratios in Roller Bearings", NASA (X-3048, 

September 1978. 

7. Nypan, L.J., "Measurement of Separator Contact Forces 

in Ball Bearings Using a Derotation Prism", Journal of 

Lubrication Technology, Trans. ASME, Series F, Vol. 101, 

No. 2, April 1979, pp. 180-189. 

13 

- 
Lube Oil Jets ---- -' 

Radial Load 

Thin Section Guide Bearing -I Test Bearing 

Figure la Schematic of Shaft Assembly 
- 

Outer ring 

- and protractor 

Modified 

roller - 

- Cage 

--Inner ring 

Figure lb Enlargement of Data Photograph 

Figure 2 Modified Roller 

15 
.._.. -..~ -_I_- 

Figure 3 Variability in Skew Angle 

Due to Film Measurement 
, 1: 

Figure 3F Fast Fourier Transform of 

Data in Figure 3 

17 
- I 

iZl RADIAL SKEW 

0 TANGENTIAL SKEW 

4055 RPM 4/19/79 

0.18 Mu to.0073 IN) CLEARANCE 

REV 2 RDG 2 

0.4537 CAGE/S?AFT SPEED RAT!0 

0 DEGREES M!SALIGNMENT 

Figure 4a Roller Skeg, 0.18.mm Clearance 

Bearing, 0 Misalignment 

18 

___. ._. - . . 
Figure 4aF Fast Fourier Transform of 

Data in Figure 4a 

19 

-- 
Figure 4b Roller Skew, 0.18 mm Clearance 

Bearing 0' Misalignment 

20 
- 

Figure 4bF Fast Fourier Transform of 

Data in Figure 4b 

21 
2 ?I RAD!AL SKEW 

ro)_ I 0 'TANGENTIAL SKEW 

12161 RPM 4/30/79 

0.1s MM (0 0073 Ih) CLFARANCE 

z 

REV*2 RDG*l 

oI 0,4433 CAGE/S?AFT SPEED RAT!0 

0.00 DEGREES M!SALIGNMENT 

z 

'l?'_ 

I 

Figure 4c Roller Skew, 0.18 mm Clearance 

Bearing, O" Misalignment 

22 
I - .- 

Figure 4cF Fast Fourier Transform of 

Data in Figure 4c 

23 
2; C RADIAL SKEW 

. 

'7: 0 IANGENT!AL SKEW 

4!35 :iPY 6/l/79-2 

oi 5.16 '.iM to,0073 I:.) CLFAR,ANCE 

rj' 

REV*1 STRT 057 

71 

0.4523 CACE/SdAFi ?FEFD ?ATl@ 

Figure 5a Roller Skew, 0.18 mn Clearance 

Bearing, 0.25' Misalignment 

24 
Figure 5aF Fast Fourier Transform of 

Data in Figure 5a 

25 
z Zl RADIAL SKEW 

rJ)_ 1 0 TANGENTIAL SKEW 

6169 RPM 5/31/75 

z 

0.16 MU (O.C@73 IN1 CLEARANCE 

REV*! STRT 012 -PI 

0.4531 CAGE/SfiAFT SPEED RAT'0 

0.25 DEGREES U!SALIGNMENl 

z 

Figure 5b-1 Roller Skew, 0.18 n-m Clearance 

Bearing, 0.25' Misalignment 

26 
‘. i 

Figure 5b-1F Fast Fourier Transform of 

Data in Figure 5b-1 

27 
A __-. - --..-- . -.- 4 . 

Figure 5b-2 Roller Sk&y, 0.18 mm Cl&rance 

. . 'B'earitig, 0.25O Misalignment 

28 
I 

FREPCENC’? 

F%g$+ 5b-iF .F&st.F&i&r TranSdti of 

Data in Figure 5b-2 

29 

-- - --- - 
A_ ---- -- ‘-_A__ -_-- .-._ 

;3 RADIAL SKEW 

0 TANGENTIAL SKEW 

12346 R!'U 6/l/73 

0.16 MM fO.0073) CLEARANCE 

REV 1 RDC 1 

0.454! CACFiS3AFT SPEED 9ATI@ 

0.2s DEGREES M!SALICNMENT 

Figure 5c-1 Roller Skew, 0.18 mm Clearance 

Bearing, 0.25O Misalignment 

30 

_-. .~ 

----- - --7 .-_~- ~-. --. .~ _ - 

,. _ . . :. 
Figure 5c-1F Fast Fourier Transform of 

Data in Figure 5c-1 

31 

- -- -. 
r-L> 

cs 22 RADIAL SYEW 

Ic)- I 3 TANCENT'AL SYEd 

12345 fl"U 5/c:i7"-2 _I 

:: 

3.16 YU tD.\??73 Ih: CLFARANCF: 

REVOLUT'bN 2 

c-- 

I 

3.4536 CAC-E/'S-lAFT SPCFD TAT'? 

Figure 5c-2 Roller Skew, 0.18 mm Clearance 

Bearing, 0.25' Misalignment 

32 
FREPUENC.Y FREPUENCY 

Figure 5c-2F Fast Fourier Transform of 

Data in Figure 5c-2 

33 
G ‘5 

I.1 

PI RADIAL SYEW 

Iv? 0 TANGENT'AL SKEW 

4020 RrU 6/&/7'3 

0.16 MM (0.0073 Ih) CLFARANCE c) 

I=, 

REVI RSf 1 

-- 

I 0.45:; CAGE/SrlAFT S"EFD r(AT'O 

0.50 DEC-REFS M'SAL!EKUENT 

cl 

3 

Figure 6a Roller Skew, 0.18 mm Clearance 

Bearing, 0.50' Misalignment 

34 
FREOUENC'f 

FREQUENCY CREPUENiY '- 

Figure 6aF Fast Fourier Transform of 

Data in Figure 6a 

35 
ZJ RADIAL SKEW 

0 rANGEbT'AL SKEW 

E13i RPM 06/06/79-Z 

0.18 10.0073 IN1 CLEARANCE 0 

w -1 REV sr 193 

I 

0.4545 CAGE/S?AFT SPEED RATIO 

0.5 DEGREF M!SALIGNMENT 

Figure 6b-1 Roller $kew,.8.18 mu.Clearance 

Bearing, 0.50 Misalignment 

36 
Figure 6b-1F Fast Fourier,Transform of 

Data in Figure 6b-1 

37 

- 
3 :: 

T, RA9'AL :Yt'N 

C TANCENT'AL :'(rW 

E’S, F;PW SiE./73-2 

0.!6 44'4 t$.CC!73 Ih! CLFA~ANCF: 

REV : 'lr'c- 1 

0 4>A7 iACF;S-IA=: EpEF3 '(AT'3 

5 DECREFS M'SAL!6tGU'KT 

Figure 6b-2 Roller Skew, 0.18 mm Clearance 

Bearing, 0.50' 'Misalignment 

38 
Fourier Plot not possible as data 

does not cover 360° 

Figure 6b-2F 

39 
PI RADIAL SKEW 

0 TANGENTIAL SKEW 

12236 R"M 6/6/79-3 

0.16 MM (0.0073 IN) CLEARANCE 

REVOLUTION 1 

0.4557 CAGE/SilAFT SPEED RATIO 

0.5 DEGREFS MISALIGNMENT 

Figure 6c-1 Roller Skew, 0.18 mm Clearance 

Bearing, 0.50° Misalignment 

40 
F 

Figure 6c-1F Fast Fourier Transform of 

Data in Figure 6c-1 

41 
z Fl RADIAL SKEW 

P-J)_ I 0 TANGENTIAL SKEW 

12236 Q"Y 6/6/79-J 

z 

0.16 MM CO.0073 IN1 CLEARANCE 

REV 2 RDG I b- I 

0.4557 CAGE/SdAFT SPEFD RATIO 

0.5 DEEREFS U!SALINGMENT 

z 

Figure 6c-2 Roller Skew, 0.18 mm Clearance 

Bearing, 0.50' Misalignment 

42 

1~111111111111111 WIIII II I 111111 Ill Ill1 ~111111 Ill I II Ill II I Ill1 II I Ill 1111IIIIImIII~III ImimlTIIR-llIIml1l1 111111~111 I 1111 I 
.’ 

” 

:; 

K. 

‘1 

Figure 6c-2F Fast Fourier Transform of 

Data in Figure 6c-2 

43 
Figure ,6c-3 Roller Skew, 0.18 mm Clearance 

Bearing, Ov500 Misalignment 

44 
Figure 6c-3F Fast-,Fourier Transform of 

Data in Figure 6c-3 

45 
1 

1 

Z RA3'AL SKEW 

0 TANGENTIAL SKEW 

4247 RrM Fj1'11/73-2 

3.16 MS4 to.0073 Ihl CLFASANCE 

REVOLIIi'ON 1 

0.4541 c'AGE/S?AFT :PEFD RAT"? 

-.5 DECREFS M'SALIEhMENT 

Figure 7a-1 Roller Skew, 0.18 mm Clearance 

Bearing, -0.50 Misalignment 

46 
Figure 7a-1F Fast Fourier Transform of 

Data in Figure 7a-1 

47 
z Zl RAD!AL SKEW 

me 

I 0 TANGENTIAL SKEW 

4247 RPM 6/11/73-Z 

z 

0.16 MU (0.0073 Ik) CLEARANCE 

b- REV2 RDGI 

I 

0.4541 CAGE/S?AFT SPEFD RATI@ 

-.5 DEGREES M'SALIGtiMENT 

z 

'n 

Figure 7a-2 Roller Skew, 0.18 mm Clearance 

Bearing, -0.50 Misalignment 

48 
-,---I32 !6 ‘. - ” ?? 

Figure 7a-2F Fast Fourier Transform of 

Data in Figure 7a-2 

54 ?? 

49 
z 

,,I 

3 RADIAL SYEW 

.CI 0 TANGENTIAL SYEW 

6323 Rrrvl &/5/73-2 

01 3 '6 MV, tD.L7373 IN1 CLFASANCE 

3 45,'s CACE;SaAFT SFEFD 9AT'@ 

[ -.j DEGREfS M~S~LICNUENT 

Figure 7b-1 Roller Skew, 0.18 mm Clearance 

Bearing, -0.50 Misalignment 

50 

I 

._ --..- . . . . ..--.I 

,,.__-_.__ _--. . . ., ____._ . . I ,...... .----. .- . .._. .m. ma , . 

~-. 
FREQUENCY 

.03 

03 ‘5.03 lz.02 Ai.?? 

FREQUENCY 

Figure 7b-1F Fast Fourier Transform of 

Data in Figure 7b-1 

51 
a RAD!AL SKEW 

0 rANGENT'AL SKEW 

6330 RPM S/G/7,3-2 

0.16 UM (0.0073 Ihl CLFARANCE 

REV2 RDGI 

O.d545 CAGE/S?AFT SCEFD RATIO 

-.5 DEGREFS MlSALlCNUENT 

Figure 7b-2 Roller Skew, 0.18 mm Clearance 

Bearing, -0.50 Misalignment 

52 
03 

FREOLIENCY 

b 

23 ‘8 03 Yi.32 rt. 23 04 .o.* 

EREIIIJENCY 

Figure 7b-2F Fast Fourier Transform of 

Data in Figure 7b-2 

53 

-- 
z [II RADIAL SKEW 

13.. I 0 rANGENT[AL SKEW 

12151 RPM e/11/73-4 

z 

0.16 MU (0.0073 IN1 CLFARANCE 

REVo' STRT'44 w- I 

0.4547 CAGE/S;-IAFT SPEFD RAT'0 

-0.5 DEGREFS MISALIGNMENT 

0 0 

Figure 7c-1 Roller Skew, 0.18 mm Clearance 

Bearing, -0.50 Misalignment 

54 
0 n 

\ ,. 

t 

Figure 7c-l.F Fast Fourier Transform of 

Data in Figure 7c-1 

55 
z RADIAL SYE# 

3 TANGFNT'AL SYEB 

'2'6' F;pw b/11/73-4 

Figure 7c-2 Roller Skew, 0.18 mm Clearance 

Bearing, -0.50 Misalignment 

56 
II -- -- 

FRCOUENCY FREOIIENC’! 

Figure 7c-2F Fast Fourier Transform of 

Data in Figure 7c-2 

57 
2 ?I RADIAL SYEW 

IFI I 0 TANGENTIAL SYEW 

4000 RPU 1/23/73-l 

2 

0.2! MU (0.0063 IH) CLFARANCE 

REV: RDGi -t . I 

0.453; CAGE/SdAFT Sf-'EFD 9AT!@ 

0 DEGREFS MISALIGNWENT 

c) 

a 

Figure 8a Roller Skew, 0.21 mm Clearance 

Bearing, 0' Misalignment 

58 
Figure 8aF Fast Fourier Transform of 

Data in Figure 8a 

59 
?J RADIAL SKEW 

0 TANGENTIAL SKEW 

6136 RPM J/27/79-2 

0.21 MU 10.0063 iFi1 CLFARANCE 

REVOLUT'ON 2 

0.4521 CAGF/SYAFT SPEED RATIO 

0 DECREE M'SALlfKMENT 

Figure 8b Roller Skeg, 0.21 mm Clearance 

Bearing, 0 Misalignment 

60 
FREPLlENCY 

Figure 8bF Fast Fourier Transform of 

Data in Figure 8b 

61 
C!I RADIAL S!CEW 

0 'TANGENTIAL SKEW 

12113 RPM l/23/79-3 

0.21 MM (0.0083 IN) CLFARANCE 

REV.1 RDG.2 

014524 C.AGE/SdAFi SFEFD RAT'@ 

0 DEEREFS M'SALIENMENT 

Figure 8c Roller Skew, 0.21 rm Clearance 

Bearing, 0' Misalignment 

62 
Figure 8cF Fast Fourier Transform of 

Data in Figure 8c 

63 
CJ 

G C!l RADIAL :L(EB 

'-- 1 0 rAkGEF;T'AL :YE'U 

4529 '?PW '/23/73-l 

CJ 0.21 MU tO.S?lj Ih! CLFARANCF: 

'3 

RE'JOLUT'ON 2 

oI 

O.d54J CAC-F/SrlAFT :rEFD TAT'@ 

Figure 9a Roller Skew, 0.21 mm Clearance 

Bearing, 0.25O Misalignment 

64 
Figure 9aF Fast Fourier Transform of 

Data Ln Figure 9a 

65 
=: Zl RADIAL SKEW 

*- 0 TANCENT'AL SYEW I 

6119 5ru !/25/75-2 

0.21 MM (0.0263 Ihl CLFARANCE 

=: 

REVill RDFa! 

wI 0.4517 CAGEIS+AFT SPEED RATIO 

0.25 DEGREE M'SALIGNMENT 

23 

Figure 9b Roller Skew, 0.21 mm Clearance 

Bearing, 0.25' Misalignment 

66 
I 

; 

1.: 

Figure 9bF Fast Fourier Transform of 

Data in Figure 9b 

67 
Figure 9c Roller Skew, 0.21 mm Clearance 

Bearing, 0.25O Misalignment 

68 
.DO 

FREQUENCY FREQUENCY 

00 16.00 32.00 46.00 

I 

44. 

FREQUENCY 

00 

I2127 WN 1128173-I 

0.29 UN IO.0013 Ill) CLEARANCE 

REV.1 me.2 

O.+S25 CAOEISHA~T WEED RATIO 

.21 DECREE3 NISALIONNENT 

.OO 

FREPUENCY 

Figure 9cF Fast Fourier Transform of 

Data in Figure 9c 

69 
a RAD!AL SKEW 

0 TANGENTIAL SKEW 

A062 R"M 2/7/79 

0.21 MM (0.0063 IFi) CLEARANCF 

REV@lUT'(IN 2 

0.4545 CAGE/S?AFT SPEED SATlO 

0.5 DEGREES YISALIE~GMENT 

Figure 10a Roller Skew, 0.21 mm Clearance 

Bearing, 0.50' Misalignment 

70 
FRt0UENC.f 

Figure 1OaF Fast Fourier Transform of 

Data in Figure 10a 

71 

---- -- -- -- - 

., 1. 

--.:‘..-.*-~,~. -. ---. ._-. _-.-- 

,,, .,,. “.; ..’ ‘_ ‘. __;--- 

.‘.,..’ I ,?. :‘;> : e , .J .,:..I .’ . ..‘. ,_ ,‘,.2.’ 
Figure lob-1 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50° Misalignment 

72 
FREOUENCY 

, 

a 

c 1 

!5 08 3z.37 dG.!?? 54.x -, 

FREQUENCY ~ 

Figure lob-1F Fast Fourier Transform of 

Data in Figure lob-1 

73 

I 

- --_-. _ - -- -- .l-_LI____---- __-__ -- 

,j 
z Cl RADIAL SKEW 

+ - 0 TAN6ENTlAL SKEW 

8290 RPM 2/7/79-2 

z 

0.21 MY (0.0083 IN) CLEARANCE 

. 

f 

REV*2 RDWI 

0.4544 CAOE/SHAFT SPEED RATIO 

0.5 DEBREES YISALI6NYENT 

0 

0 

. 

P4 

Figure lob-2 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50° Misalignment 

74 

- -7.. 

..‘, ,; 1. : > _, 

--- --, _ - 

.-. - .‘i 

--- - ;~-.-.I 

..: : I 

._ .., 

;. : : .-,* , .” m. . 
Figure lob-2F Fast Fourier Transform of 

Data in Figure lob-2 

75 
cd 

G E RAD!AL SKEW 

!3- 

I 0 TANfEKT!AL SKEW 

'2273 RPM 3/6i73-1 

0.21 MU tO.@CE3 itvl CLEARANCE 

z 

REVOLUT!@N 2 w‘_ 

I 0.4550 CAGE/S!fAFT SPEED RAT!@ 

0.5 DEGREFS M'SAL!ENMENT 

0 0 

in, 

I 

Figure lOc-1 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50' Misalignment 

76 
FREQUENCY FREPUENCY 

Figure 10c-1F Fast Fourier Transform of 

Data in Figure lOc-1 

77 
0.00 

Zl RADIAL :L(EW 

0 TANfENT!AL SKEW 

12273 RPW 3/6i73-1 

0.2! Mw to.Dc?E3 iti) CLEARANC 

REVDLUT!llN 3 

0.4550 CAC-E/S?AFT SPEFD RAT'@ 

0.5 DECREFS MISALICNUENT 

Figure lOc-2 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50' Misalignment 

78 
Figure lOc-2F Fast Fourier Transform of 

Data in Figure lOc-2 

79 

- .- 
CJ 

G ;? RADIAL 5YEw 

13- 0 TANGEKT'AL SYEW , 

12273 RPW 3/6/79-l 

z 

0.2! MU (O.SGE3 ih1 CLEARANCE 

REv@LL':!@N d wO,dl):O CAC-E,'Z-IAFr SPEFD TAT'@ 

0.5 DECREF:, M'SAL!E~GUEKT 

0 

0 

n- I 

Figure lOc-3 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50° Misalignment 

80 
03 

FRECIUENCY 

3;. I? lS.?l 

cRE3UENCY 

Figure lOc-3F Fast Fourier Transform of 

Data in Figure lOc-3 

81 
D G C RADIAL SKEW 

*- 1 0 TANGENTIAL S1(EW 

12273 RPM 3/6/79-l 

," 

0.21 MM (0.0063 Ihr CLFARANCE 

REV 5 RDG 1 -TI 

0.4550 CAGE/S;IAFT SPEED RATIO 

I 5 DEGREES U'SALIGNMENT 

Figure lOc-4 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50' Misalignment 

82 
3: 

c!t: CUENC':' 

Figure lOc-4F Fast Fourier Transform of 

Data in Figure lOc-4 

83 

- ..- 
0 

0 Cl RADIAL SKEW 

. 

7 - 0 TANGENTIAL SKEW 

12273 RPU 3/6/79-l 

0 

0.21 MM (0.0083 IN1 CLEARANCE 

0 

. REV6 RDGl *- I 0.4550 CAGE/SHAFT SPEED RATtO 

,5 DEGREES MISALIGNMENT 

0 

0 

. 

“: a 

Figure lOc-5 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50° Misalignment 

84 
.33 

FREQUENCY 

lZZT3 RPY 3/5ir!3-I 

0.21 MY IO.0063 IN1 CLFARANCE 

REV5 11051 

0,4SSO CACC;SklAFT SPEED IATl(r 

5 DECSEFS Y!SALIGNMEt~T 

FREOUENCY 

Figure lOc-5F Fast Fourier Transform of 

Data in Figure lOc-5 

85 
-I [fl RADIAL SKEW -. 7 0 TANGENTIAL SKEW 

12273 RPM 3/6/79-l 

z 

0.21 MU (0.0083 IN1 CLEARANCE 

. REV7 RC61 Q I 0.4550 CAGE/SHAFT SPEED RAT16 

.5 DEGREES MISALIGNMENT 

Figure lOc-6 Roller Skew, 0.21 mm Clearance 

Bearing, 0.50° Misalignment 

86 
z ‘0.03 !5 00 32.03 ,_, 46 "3 5.4 00 

FREQUENCY 

122n RPY 3/5,79-t 

0 21 YY IO.0363 Ik’ CrFlRANCE 

REVI RilEI 

33 

FREQUENCY 

FREOUENCY 

Figure lOc-6F Fast Fourier Transform of 

Data in Figure lOc-6 

87 
z q RADIAL SKEW 

P-Jt 0 'TANGENTIAL SKEW 

4064 RPM 4/2/79-2 

0.21 MM (0.0063 IN) CLFARANCE 

z 

REVOLUT!ON 2 

-rI 0.4532 CAGE/SiiAFT SPEED RATIO 

-0.5 DEGREFS MISALIGNMENT 

z 

10& I 

Figure lla Roller Skew, 0.21 mn Clearance 

Bearing, -0.50° Misalignment 

88 
Figure 1laF Fast Fourier Transform of 

Data in Figure lla 

89 
=I 13 RAD!AL SKEW 

*- 

I 0 TANGENT!AL SYEW 

6267 RPW 4/J/79-2 

0 0.21 MU to.0063 Ihl CLEARANCE 

c) 

REV@LL'Tl@N 2 -I-- 

1 

0.4535 CAGE/S;IAFT SPEED RAT'@ 

-0.5 DEGREES U~SALIGMIENT 

," 

in, 

, 

Figure lib-1 Roller Skew, 0.21 mm Clearance 

Bearing, -0.50° Misalignment 

90 
Figure lib-1F Fast Fourier Transform of 

Data in Figure lib-1 

91 
z Z RADIAL SKEW 

roe I 0 TANGENTIAL SYCW 

6267 r(rtd 413179-1 

c 

0.21 MM tO.O?EJ Il\r) CLFARANCF 

c3 

REV3 RDGl CT- ! 

.4535 CAGE/SiJAFT :rEFD FAT'@ 

-.5 DEGREFS M'SALIGNUENI 

z 

n- I 

Figure lib-2 Roller Skew, 0.21 mm Clearance 

Bearing, -0.50° Misalignment 

92 
Figure lib-2F Fast Fourier Transform of 

.Data in Figure lib-1 

93 
1 

3 RADIAL SKEW 

0 TANGENTIAL SKEW 

1iiiE RF!,4 d/Z/i?-1 

0 i! MM IO 3063 IN: CLF~~~NGE 

REVCLlil'CN 2 

O.fi55L C.AGE;S+AFi SP:kD 94i'O 

-0.5 DEGREFS M'SALIGNMENT 

Figure llc-1 Roller Skew, 0.21 mm Clearance 

Bearing, -0.50' Misalignment 

94 
P 

FREQGENCY 

!5.13 32 

FREPU 

7 

Gi.93 54.32 

Y 

33 !6.13 3; cl? 

FREQUENCY 

Figure llc-1F Fast Fourier Transform of 

Data in Figure llc-1 

95 

- -- 
2 'c RADIAL SKEW 

lo- I 0 TANGENTIAL SL(EW 

12226 RPM 413173-2 

0.21 MM (O.OSE3 Ih) CLEARANC.E 

z REVS3 RDGt! CT- I 0.4552 CAGE/SdAFT SPEFD '(AT'O 

-0.5 DEGREES M!SALIGNMENT 

0 0 

Figure llc-2 Roller Skew, 0.21 mm Clearance 

Bearing, -0.50° Misalignment 

96 
FREQUENCY FREQUENCY 

Figure llc-2F Fast Fourier Transform of 

Data in Figure llc-2 

97 
Z RADIAL SYEW 

0 TANGENTIAL SKEW 

12225 ZrM A/3/73-2 

0.2! MIO (O,Oc763 Ih) CLFARANCE 

REVs4 SDGn' 

0.4552 CAGE/SdAFT :f'EFD 'XAT'O 

-0.5 DEGZEE5 U!SALIC~~UENT 

Figure llc-3 Roller Skew, 0.21 mm Clearance 

Bearing, -0.50° Misalignment 

98 
.oo 

FREQUENCY 

.oo 

FREQUENCY 

FREQUENCY 

12226 RPU 413/13-2 

0.21 MY 10.0363 IN1 CLEMANCE 

REVI ROC1! 

0.4552 CACF/SRAFT WEED qAT!6 

-0.5 DEClEES YISALICNYENT 

z 

‘ol.03 # 10.00 32.00 46.03 64.03 

FREQUENCY 

Figure llc-3F Fast Fourier Transform of 

Data in Figure llc-3 

99 
Table I 

Roller Bearing Specifications 

Inner Race 

Bore Dia. mm (in) 

Raceway Dia. mm (in) 

Flange Dia. mm (in> 

Width mm (in> 

Groove Width mm (in) 

Flange Angle 

Outer Race 

Outer Dia. mm (in> 

Raceway Dia. mm (in) 

Width mm (in) 

Rollers 

Diameter m (in> 

Length - overall mm (in> 

effective mm tin> 

flat mm (in> 

Crown Radius mm (in> 

End Radius mm (in> 

Number 

118 (4.6457) 

131.66 (5.1834) 

137.47 (5.4122) 

26.92 (1.060) 

14.59 ( -5746) 

0 degree 

164.49 (6.4760) 

157.08 (6.1842) 

23.9 ( .942) 

12.65 ( -4979) 

14.56 ( -5733) 

13.04 ( .5133) 

8.40 ( 03307) 

622.3 (24.5) 

inf. 

28 

Cage 

Land Dia. 

Axial Pocket Clearance 

; ii", 137.95 (5.4312) 

.020 ( .0008) 

Tangential Pocket Clearance mm (in) .221 ( .0087) 

Single Rail Width mm (in) 4.6 C .18) 

Clearance 

Serial No. A2284 mm (In) 0.18 (0.0073) 

Serial No. A2279 mm (in) 0.21 (0.0083) 

100 
Misalignment Speed Case 

Degrees RPM 

0 4000 

0 8000 

0 12000 

0.25 4000 

0.25 8000 

0.25 12000 

0.5 4000 

0.5 8000 

0’ 

w 0.5 

-0.5 

-0.5 

-0.5 

12000 

4000 

8000 

12000 

Table 2. - Summary of Test Conditions and Data 

[PWA 5410433 

(a) Serial No. A2284 - 0.18 mm (0.0073 in.) Clearance 

Figure 

4a 

4b 

4c 

5a 

5b-1 

5b-2 

5c-1 

5c-2 

6a 

6b-1 

6b-2 

6c-1 

6c-2 

6c-3 

7a-1 

7a-2 

7b-1 

7b-2 

7c-1 

7c-2 

Exact Speed Date, Film 

RPM Set 

4 055 4/19/79-l 

8 229 4/30/79-l 

12 161 4/30/79-2 

4 135 6/l/79-2 

8 169 5/31/79-l 

8 169 5/31/79-l 

12 346 6/l/79-2 

12 346 6/1/79-l 

4 020 6/8/79-l 

8 137 6/a/79-2 

8 137 6/8/79-2 

12 238 6/E/79-3 

12 238 6/a/79-3 

12 238 6/a/79-3 

4 247 6/11/79-2 

4 247 6/11/79-2 

a 390 a/6/79-2 

8 390 a/6/79-2 

12 181 6/H/79-4 

12 181 6/11/79-4 

Cage to Shaft 

Speed Ratio 

0.4537 

0.4545 

0.4493 

0.4529 

0.4531 

0.4531 

0.4538 

0.4541 

0.4545 

0.4545 

0.4557 

0.4557 

0.4541 

0.4541 

0.4541 

0.4545 

0.4545 

0.4547 

0.4547 

% 

slip 

0.6 Rev 2 Rdg 2 

0.4 Rev 1 

1.5 Rdg 3 

0.7 Rev 1 Starts 57O 

0.7 Rev 1 Starts 12O 

0.7 Rev 2 Rdg 2 

0.5 Rev 1 Rdg 1 

0.5 Rev 2 

Rev 1 Rdg 1 

0.4 Rev Starts 193O 

0.4 Rev Starts 00, inc. 

0.1 Rev 1 

0.1 Rev 2 Rdg 1 

0.5 Rev 3 Rdg 1 

0.5 Rev 1 

0.5 Rev 2 Rdg 1 

0.4 Rev 1 Rdg 1 

0.4 Rev 2 Rdg 1 

0.3 Rev 1 Starts 114O 

0.3 Rev 2 Rdg 1 
Misalignment 

0 

0.25 

0.25 

0.25 

0.5 

0.5 

z: h, 0.5 

-0.5 4000 

-0.5 8000 

-0.5 

Speed Case 

RPM 

4000 

8000 

12000 

4000 

8000 

12000 

4000 

8000 

12000 

Table 2. - Summary of Test Conditions and Data 

[PWA 5410433 

(b) Serial No. A2279 - 0.21 rmn (0.0083 in.) Clearance 

12000 

Figure 

8a 

8b 

Exact Speed Date, Film Cage to Shaft % 

RPM Set Speed Ratio slip 

4 000 1/23/79-l 0.4537 0.6 

8 136 3/27/79-2 0.4521 0.9 

8c 12 113 l/23/79-3 0.4524 0.8 

9a 4 029 1/29/79-l 0.4540 0.5 

9b 8 119 l/25/79-2 0.4517 1.0 

9c 12 127 1/26/79-l 0.4525 0.8 

10a 4 082 2/7/79-l 0.4545 0.4 

lob-1 8 290 2/7/79-2 0.4544 0.4 

lob-2 8 290 2/7/79-2 0.4544 0.4 

lOc-1 12 273 3/6/79-l 0.4550 0.3 

lOc-2 12 273 3/6/79-l 0.4550 0.3 

lOc-3 12 273 3/6/79-l 0.4550 0.3 

lOc-4 12 273 3/6/79-2 0.4549 0.3 

lOc-5 12 273 3/6/79-2 0.4549 0.3 

lOc-6 12 273 3/6/79-2 0.4549 0.3 

lla 4 084 4/2/79-2 0.4532 0.7 

lib-1 8 267 4/3/79-2 0.4535 0.8 

llb-2 8 267 4/3/79-2 0.4535 0.8 

llC-1 12 228 4/3/79-l 0.4552 0.2 

llc-2 12 228 4/3/79-l 0.4552 0.2 

llc-3 12 228 4/3/79-l 0.4552 0.2 

Rev 2 Rdg 2 

Rev 2 After 

0.5 misaligned 

Rev 1 Rdg 2 

Rev 2 

Rev 1 Rdg 1 

Rev 2 Rdg 2 

Rev 2 

Rev 1 

Rev 2 Rdg 1 

Rev 2 

Rev 3 

Rev 4 

Rev 5 

Rev 6 

Rev 7 

Rev 2 

Rev 2 

Rev 3 

Rev 2 

Rev 3 

Rev 4 
1. Report No. 

NASA CR-3381 

4. Title and Subtitle 

2. Government Accession No. 3. Recipient’s Catalog No. 

ROLLER SKEWING MEASUREMENTS 

ROLLER BEARINGS 

7. Author(s) 

Lester J. Nypan 

10. Work Unit No. 

9. Performing Organization Name and Address 

California State University, Northridge 

Northridge, California 91330 

11, Contract or Grant No. 

12. Sponsoring Agency Name and Address 

National Aeronautics and Space Administration 

Washington, D. C. 20546 

15. Supplementary Notes 

Lewis Technical Monitor: Harold H. Coe 

Final Report 

16. Abstract 

Measurements of roller skewing in a 118 mm bore roller bearing operating at shaft speeds to 

12,000 rpm are reported. High speed motion pictures of a modified roller were taken through a 

derotation prism to record skewing as the roller moved through loaded and unloaded regions of 

the bearing. Subsequent frame by frame measurement of the photographic film provided information on roller skewing. Radial and tangential skew amplitudes of 0. 4 to 0. 5 degrees were 

observed with 0.5 degree misalignment. 

7. Key Words (Suggested by Author(s)) 

Roller bearings; Roller skewing; 

Misalignment; Skew angle; Cylindrical 

18. Distribution Statement 

Unclassified - unlimited 

19. Security Classif. (of this report) 

Unclassified 

20. Security Classif. (of this page) 

Unclassified 

Subject Category 37 

21. No. of Pages 22. Price’ 

104 A06 

* For sale by the National Technical Information Service, Sprrnefleld. Vlrglnla 22161 

NASA-Langley, 1981