| Present Technology of Rolling-Element Bearings, |
JAN 1983 |
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| Authors:
Richard J. Parker; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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 | The specification of rolling-element bearings has progressed significantly beyond the selection of ball or roller bearings from a manufacture's catalog. Applications are becoming more commonplace where novel materials, unique lubrication techniques, and sophisticated computer analysis are required to satisfy difficult environmental and operating conditions. Primary motivation for advancements in the state of technology of rolling-element bearings has come from aerospace requirements. In particular, the aircraft gas-turbine engine has provided the ... |
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| Large-Bore Tapered-Roller Bearing Performance and Endurance to 2.4 Million DN, |
JAN 1983 |
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| Authors:
Richard J. Parker; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| The performance and endurance life of 120.65-mm (4.75-in.) bore tapered-roller bearings of two designs were investigated under heavy combined radial and thrust loads. Performance tests were run up to 15 000 rpm with the modified standard design bearing and to 20 000 rpm with the computer optimized design bearing. Temperature distribution and bearing heat generation were determined as functions of shaft speed, radial and thrust loads, lubricant flow rate, and ... |
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| Rolling-Element Fatigue Life of AISI M-50 and 18-4-1 Balls |
APR 78 |
20 pages |
| Authors:
Richard J. Parker; Erwin V. Zaretsky; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CEN TER
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 | Rolling-element fatigue studies were conducted with VIM-VAR AISI M- 50, EFR 18-4-1, and VAR 18-4-1. Groups of 12.7-mm (1/2-in.) diameter balls of each material were tested in the five-ball fatigue tester. Test conditions included a load of 1540 N (347 lbf) giving a maximum Hertz stress of 5520 MPa (800 000 psi), a shaft speed of 10 700 rpm, and a contact angle of 30 deg. Tests were run at ... |
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| rolling-element fatigue lives of four m-series steels and aisi 52100 at150 degrees f |
FEB 71 |
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| Authors:
Richard J. Parker; Erwin V. Zaretsky; marshall w. dietrich; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OHIO LEWIS RESEARCH CENTER
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| rolling-element fatigue studies were performed with 1/2-inch-(12.7- min-) diameter balls of aisi m-1, m-2, m-10, m-50, and 52100. tests were run in five-ball fatigue testers at 800 000 psi (5.52 x 10 to the 9th power n/m squared) and at a temperature of 150 degrees f(340 k). care was taken to maintain constant all the variables known to affect rolling-element fatigue life. the longest lives were obtained ... |
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| Bearing Life and Failure Distribution as Affected by Actual Component Differential Hardness |
NOV 1965 |
22 pages |
| Authors:
Erwin V. Zaretsky; Richard J. Parker; William J. Anderson; David W. Reichard; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| Rolling-contact fatigue tests were performed on SAE 52100 207-size deep-groove ball bearing determine the relation between bearing fatigue life and actual bearing component hardness differences and the effect of actual component hardness differences on bearing fatigue life scatter. The 207-size bearings with inner and outer races from the same heat of SAE 52100 material and with nominal Rockwell C hardnesses of 63 were assembled with SAE 52100 balls from the ... |
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| Apparatus for Studying Ball Spinning Friction |
MAY 1965 |
14 pages |
| Authors:
Steven T. Miller; Richard J. Parker; Erwin V. Zaretsky; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| An experimental apparatus was designed and constructed at the NASA lewis Research Center to study one aspect of spinning friction based on interfacial slip over the entire ball-race contact area. The apparatus is capable of measuring spinning moments of less than 0. Ol inch-pound at maximum Hertz contact stresses to over 400 000 psi, speeds to 3500 rpm, and under varying contact configurations and conditions. From the torque measurement, a ... |
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| Effect of Component Differential Hardness on Residual Stress and Rolling-Contact Fatigue |
MAR 1965 |
17 pages |
| Authors:
Erwin V. Zaretsky; Richard J. Parker; William J. Anderson; Steven T. Miller; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| Residual stress measurements were made in the zone of resolved shearing stress on five SAE 52100 upper test ball specimens with an average Rockwell C hardness of 63.2. These upper test ball specimens were run against lower test balls of nominal Rockwell C hardnesses of 60, 62, 63, 65, and 66 until either ft conditions included an or both components failed because of fatigue. Test conditions included an average race ... |
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| Effect of Component Differential Hardnesses on Rolling-Contact Fatigue and Load Capacity |
MAR 1965 |
24 pages |
| Authors:
Erwin V. Zaretsky; Richard J. Parker; William J. Anderson; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| The five-ball fatigue tester was used to study the effect of component hardness combinations on the fatigue life of rolling elements subjected to repeated stresses applied in rolling contact. SAE521OO steel balls from the same heat of material were tempered to a range of Rockwell C hardnesses from 59.7 to 66.4. Groups of balls having average Rockwell C hardnesses of 60.5, 63.2, and 65.2 were used as upper test balls ... |
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| Surface Failure of Titanium Carbide Cermet and Silicon Carbide Balls in Rolling Contact at Temperatures to 2000 degrees F |
AUG 1964 |
26 pages |
| Authors:
Richard J. Parker; Salvatore J. Grisaffe; Erwin V. Zaretsky; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| The five-ball fatigue tester was used to study the behavior of nickel- bonded titanium carbide cermet and self-bonded silicon carbide balls under repeated stresses applied in rolling contact. Test conditions were 800 and 700 F, a contact angle of 200, and a shaft speed of 950 rpm with a mineral oil lubricant. The nickel-bonded titanium carbide - cermet balls were tested at maximum Hertz stresses from 400,000 to 550,000 psi, ... |
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| Surface Failure of Alumina Balls Due to Repeated Stresses Applied in Rolling Contact at Temperatures to 2000 degree F |
MAY 1964 |
18 pages |
| Authors:
Richard J. Parker; Salvatore J. Grisaffe; Erwin V. Zaretsky; NATIONAL AERONAUTICS AND SPACE ADMINISTRATION CLEVELAND OH LEWIS RESEARCH CENTER
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| The five-ball fatigue tester was used to study the behavior of alumina balls under repeated stresses applied in rolling contact. Hot-pressed and cold-pressed-and-sintered 1/2-inch alumina balls were tested at 800 and 7000 F, maximum Hertz stresses of 250,000 to 850,000 psi, a contact angle of 200, and a shaft speed of 950 rpm with a mineral oil lubricant. Failure appearance in alumina was unlike fatigue pits found in bearing steels ... |
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