ASTM C808-75(2021)
(Guide)Standard Guide for Reporting Friction and Wear Test Results of Manufactured Carbon and Graphite Bearing and Seal Materials
Standard Guide for Reporting Friction and Wear Test Results of Manufactured Carbon and Graphite Bearing and Seal Materials
SIGNIFICANCE AND USE
2.1 The purpose of this guide is twofold. First, it is a research tool that will aid in the analysis and correlation of test results obtained on various test devices by different investigators. Second, it serves to identify important considerations that must be made in testing to make the results easily understood and comparable with the results of other investigators.
SCOPE
1.1 This guide covers the following areas for reporting friction and wear test results of manufactured carbon and graphite bearing and seal materials:
1.1.1 Description of test device and techniques (Table 1 and Table 2.)
1.1.2 Description of carbon and graphite material test specimen (Table 3).
1.1.3 Description of mating member test specimen (Table 4).
1.1.4 Report of friction and wear test results (Table 5).
1.2 Many types of equipment and techniques will yield consistent data characterizing the friction and wear of carbon and graphite materials. However, the ranking of the materials by the various test methods used is not necessarily the same. This guide is an initial effort to promote more complete description of the test methods, whatever they may be. It is the eventual intent to identify one or more specific standard test methods when sufficient information becomes available.
1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: C808 − 75 (Reapproved 2021)
Standard Guide for
Reporting Friction and Wear Test Results of Manufactured
1
Carbon and Graphite Bearing and Seal Materials
This standard is issued under the fixed designation C808; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope This guide is an initial effort to promote more complete
description of the test methods, whatever they may be. It is the
1.1 This guide covers the following areas for reporting
eventual intent to identify one or more specific standard test
friction and wear test results of manufactured carbon and
methods when sufficient information becomes available.
graphite bearing and seal materials:
1.3 This international standard was developed in accor-
1.1.1 Description of test device and techniques (Table 1 and
dance with internationally recognized principles on standard-
Table 2.)
ization established in the Decision on Principles for the
1.1.2 Description of carbon and graphite material test speci-
Development of International Standards, Guides and Recom-
men (Table 3).
mendations issued by the World Trade Organization Technical
1.1.3 Description of mating member test specimen (Table
Barriers to Trade (TBT) Committee.
4).
1.1.4 Report of friction and wear test results (Table 5).
2. Significance and Use
1.2 Many types of equipment and techniques will yield
2.1 The purpose of this guide is twofold. First, it is a
consistent data characterizing the friction and wear of carbon
research tool that will aid in the analysis and correlation of test
and graphite materials. However, the ranking of the materials
results obtained on various test devices by different investiga-
by the various test methods used is not necessarily the same.
tors. Second, it serves to identify important considerations that
must be made in testing to make the results easily understood
1
This guide is under the jurisdiction of ASTM Committee D02 on Petroleum
and comparable with the results of other investigators.
Products, Liquid Fuels, and Lubricants and is the direct responsibil
...
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1.1 This specification covers electronic instruments intended for intermittent measuring and monitoring of patient temperatures by means of detecting the intensity of thermal radiation between the subject of measurement and the sensor.
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1.2 These procedures are not applicable to coatings that will be readily deformed under the load of the measuring gages/probes, as the gage probe must be placed directly on the coating surface to obtain a reading. Provisions for measuring on soft or tacky coatings are described in 5.7.
1.3 Coating thickness can be measured using a variety of gages. These gages are categorized as “magnetic pull-off” and “electronic.” They use a sensing probe or magnet to measure the gap (distance) between the base metal and the probe. This measured distance is displayed as coating thickness by the gages.
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SIGNIFICANCE AND USE
5.1 The Miller Number5 is an index of the relative abrasivity of slurries. Its primary purpose is to rank the abrasivity of slurries in terms of the wear of a standard reference material. The wear damage on the standard wear block is worse as the Miller Number gets higher.
5.2 The SAR Number is an index of the relative abrasion response of materials as tested in any particular slurry of interest. The SAR Number is a generalized form of the Miller Number applicable to materials other than the reference material used for the Miller Number determination. A major purpose is to rank construction materials for use in a system for pumping and fluid handling equipment for a particular slurry. It can also be used to rank the abrasivity of various slurries against any selected construction material other than the reference material specified for a Miller Number determination. The slurry damage on the specimen of material being tested is worse as the SAR Number gets higher.
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1.1 This test method covers a single laboratory procedure that can be used to develop data from which either the relative abrasivity of any slurry (Miller Number) or the response of different materials to the abrasivity of different slurries (SAR Number), can be determined.
1.2 The test data obtained by this procedure is used to calculate either a number related to the rate of mass loss of duplicate standard-shaped 27 % chromium iron wear blocks when run for a period of time in the slurry of interest (Miller Number), or to calculate a number related to the rate of mass loss (converted to volume loss) of duplicate standard-shaped wear specimens of any material of interest when run for a period of time in any slurry of interest (SAR Number).
1.3 The requirement for a finished flat wearing surface on the test specimen for a SAR Number test may preclude application of the procedure where thin (0.051 mm to 0.127 mm), hard, wear-resistant coatings will not allow for surface finishing. The 6 h total duration of the SAR Number Test may not allow establishment of a consistent rate-of-mass-loss of the unfinished surface.
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
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SIGNIFICANCE AND USE
5.1 The severity of abrasive wear in any system will depend upon the abrasive particle size, shape, and hardness, the magnitude of the stress imposed by the particle, and the frequency of contact of the abrasive particle. In this practice these conditions are standardized to develop a uniform condition of wear which has been referred to as scratching abrasion (1 and 3). The value of the practice lies in predicting the relative ranking of various materials of construction in an abrasive environment. Since the practice does not attempt to duplicate all of the process conditions (abrasive size, shape, pressure, impact, or corrosive elements), it should not be used to predict the exact resistance of a given material in a specific environment. Its value lies in predicting the ranking of materials in a similar relative order of merit as would occur in an abrasive environment. Volume loss data obtained from test materials whose lives are unknown in a specific abrasive environment may, however, be compared with test data obtained from a material whose life is known in the same environment. The comparison will provide a general indication of the worth of the unknown materials if abrasion is the predominant factor causing deterioration of the materials.
SCOPE
1.1 This test method covers laboratory procedures for determining the resistance of metallic materials to scratching abrasion by means of the dry sand/rubber wheel test. It is the intent of this test method to produce data that will reproducibly rank materials in their resistance to scratching abrasion under a specified set of conditions.
1.2 Abrasion test results are reported as volume loss in cubic millimetres for the particular test procedure specified. Materials of higher abrasion resistance will have a lower volume loss.
Note 1: In order to attain uniformity among laboratories, it is the intent of this test method to require that volume loss due to abrasion be reported only in the metric system as cubic millimetres. 1 mm3 = 6.102 × 10−5 in.3.
1.3 This test method covers five recommended procedures which are appropriate for specific degrees of wear resistance or thicknesses of the test material.
1.3.1 Procedure A—This is a relatively severe test which will rank metallic materials on a wide volume loss scale from low to extreme abrasion resistance. It is particularly useful in ranking materials of medium to extreme abrasion resistance.
1.3.2 Procedure B—A short-term variation of Procedure A. It may be used for highly abrasive resistant materials but is particularly useful in the ranking of medium- and low-abrasive-resistant materials. Procedure B should be used when the volume–loss values developed by Procedure A exceeds 100 mm3.
1.3.3 Procedure C—A short-term variation of Procedure A for use on thin coatings.
1.3.4 Procedure D—This is a lighter load variation of Procedure A which is particularly useful in ranking materials of low-abrasion resistance. It is also used in ranking materials of a specific generic type or materials which would be very close in the volume loss rates as developed by Procedure A.
1.3.5 Procedure E—A short-term variation of Procedure B that is useful in the ranking of materials with medium- or low-abrasion resistance.
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
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SIGNIFICANCE AND USE
4.1 This test method is useful for the direct measurement of the thicknesses of metallic coatings and of individual layers of composite coatings, particularly for layers thinner than normally measured with the light microscope.
4.2 This test method is suitable for acceptance testing.
4.3 This test method is for the measurement of the thickness of the coating over a very small area and not of the average or minimum thickness per se.
4.4 Accurate measurements by this test method generally require very careful sample preparation, especially at the greater magnifications.
4.5 The coating thickness is an important factor in the performance of a coating in service.
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1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
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