Standard Test Method for Fretting Wear Protection by Lubricating Greases

SCOPE
1.1 This test method evaluates the fretting wear protection provided by lubricating greases.  
1.2 The values stated in SI units are to be regarded as the standard. Other units are for information only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, See Notes 3, 4, and 6.

General Information

Status
Historical
Publication Date
31-Dec-1996
Current Stage
Ref Project

Relations

Buy Standard

Standard
ASTM D4170-97 - Standard Test Method for Fretting Wear Protection by Lubricating Greases
English language
5 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn. Contact
ASTM International (www.astm.org) for the latest information.
Designation: D 4170 – 97
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Test Method for
1
Fretting Wear Protection by Lubricating Greases
This standard is issued under the fixed designation D 4170; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope rolling elements of a bearing vibrate or oscillate with small
amplitude while pressed against the bearing race. The mecha-
1.1 This test method evaluates the fretting wear protection
nism proceeds in stages: 1) asperities weld, are torn apart, and
provided by lubricating greases.
form wear debris that is subsequently oxidized; 2) due to the
1.2 The values stated in SI units are to be regarded as the
small-amplitude motion, the oxidized detritus cannot readily
standard. Other units are for information only.
escape, and being abrasive, the oxidized wear debris acceler-
1.3 This standard does not purport to address all of the
ates the wear. As a result, wear depressions are formed in the
safety concerns, if any, associated with its use. It is the
bearing race. These depressions appear similar to the Brinell
responsibility of the user of this standard to establish appro-
depressions obtained with static overloading. Although false
priate safety and health practices and determine the applica-
brinelling can occur in this test, it is not characterized as such,
bility of regulatory limitations prior to use. For specific hazard
and instead, it is included in the determination of fretting wear.
statements, See Note 2, Note 3, and Note 5.
4. Summary of Test Method
2. Referenced Documents
4.1 The tester is operated with two ball thrust bearings,
2.1 ASTM Standards:
lubricated with the test grease, oscillated through an arc of 0.21
Test Methods for Rating Motor, Diesel, and Aviation Fuels;
rad (12°), at a frequency of 30.0 Hz (1800 cpm), under a load
Motor Fuels (Section I), Reference Materials and Blend-
of 2450 N (550 lbf), for 22 h at room temperature (Note 1).
ing Accessories (Annex 2), Reference Fuels (A2.7.3.3),
2
Fretting wear is determined by measuring the mass loss of the
and Table 32 (Specification for n-Heptane Motor Fuel)
3 bearing races.
2.2 Military Standard:
MIL-S-22473D Sealing, Locking and Retaining Com-
NOTE 1—Arc, frequency, and load are factory-set operating conditions
pounds, Single-Component
and should not be altered. The load spring constant may change over an
extended time period. Spring calibration should be checked periodically
3. Terminology
and, if necessary, a suitable shim should be fabricated to obtain the
required load (63 %) at the assembled length of the spring.
3.1 Definitions:
3.1.1 fretting wear, n—a form of attritive wear caused by
5. Significance and Use
vibratory or oscillatory motion of limited amplitude character-
5.1 This test method is used to evaluate the property of
ized by the removal of finely-divided particles from the
4 lubricating greases to protect oscillating bearings from fretting
rubbing surfaces.
wear. This method, used for specification purposes, differenti-
3.1.1.1 Discussion—Air can cause immediate local oxida-
ates among greases allowing low, medium, and high amounts
tion of the wear particles produced by fretting wear. In
of fretting wear under the prescribed test conditions. The test
addition, environmental moisture or humidity can hydrate the
has been used to predict the fretting performance of greases in
oxidation product. In the case of ferrous metals, the oxidized
5
wheel bearings of passenger cars shipped long distances. Test
wear debris is abrasive iron oxide (Fe O ) having the appear-
2 3
results do not necessarily correlate with results from other
ance of rust, which gives rise to the nearly synonymous terms,
types of service. It is the responsibility of the user to determine
fretting corrosion and friction oxidation. A related, but some-
whether test results correlate with other types of service.
what different phenomenon often accompanies fretting wear.
False brinelling is localized fretting wear that occurs when the
6. Apparatus
,
6 7
6.1 Falex Fretting Wear Tester, Model F-1581, as pur-
1
This test method is under the jurisdiction of ASTM Committee D-2 on
chased and illustrated in Figs. 1 and 2.
Petroleum Products and Lubricantsand is the direct responsibility of Subcommittee
D02.Gon Lubricating Grease.
Current edition approved June 10, 1997. Published December 1997. Originally
5
published as D 4170 – 82. Last previous edition D 4170 – 93. Verdura, T. M., “Development of a S
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.