ASTM D7546-24
(Test Method)Standard Test Method for Determination of Moisture in New and In-Service Lubricating Oils and Additives by Relative Humidity Sensor
Standard Test Method for Determination of Moisture in New and In-Service Lubricating Oils and Additives by Relative Humidity Sensor
SIGNIFICANCE AND USE
5.1 Knowledge of the water content of lubricating oils, additives, and similar products is important in the manufacture, purchase, sale, transfer, or use of such petroleum products to help in predicting their quality and performance characteristics.
5.2 For lubricating oils, the presence of water can lead to premature corrosion and wear, an increase in the debris load resulting in diminished lubrication and premature plugging of filters, impedance to the effect of additives, and undesirable support of deleterious bacterial growth.
SCOPE
1.1 This test method covers the quantitative determination of water in new and in-service lubricating oils and additives in the range of 10 mg/kg to 100 000 mg/kg (0.001 wt./wt. to 10 % wt./wt.) using a relative humidity (RH) sensor. Methanol, acetonitrile, and other compounds are known to interfere with this test method.
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 Warning—Samples tested in this test method can be flammable, explosive, and toxic. Use caution when handling them before and after testing.
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.
1.5 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
Relations
Buy Standard
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: D7546 − 24
Standard Test Method for
Determination of Moisture in New and In-Service Lubricating
1
Oils and Additives by Relative Humidity Sensor
This standard is issued under the fixed designation D7546; 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* 3.1.1 For definitions of terms used in this test method, refer
to Terminology D4175.
1.1 This test method covers the quantitative determination
of water in new and in-service lubricating oils and additives in
4. Summary of Test Method
the range of 10 mg/kg to 100 000 mg ⁄kg (0.001 wt. ⁄wt. to
4.1 An aliquot of sample is heated to a temperature between
10 % wt./wt.) using a relative humidity (RH) sensor. Methanol,
25 °C to 200 °C with 1 °C resolution. The sample is maintained
acetonitrile, and other compounds are known to interfere with
at a constant temperature for the duration of the test. Dry inert
this test method.
gas flows over the heated sample and carries the thermally
1.2 The values stated in SI units are to be regarded as
evolved moisture past a relative humidity sensor. The sensor
standard. No other units of measurement are included in this
signal is integrated over time to provide a measurement of total
standard.
mass of water in the sample.
1.3 Warning—Samples tested in this test method can be
4.2 The sample injection may be done either by mass or by
flammable, explosive, and toxic. Use caution when handling
volume.
them before and after testing.
4.3 This test method utilizes anhydrous compressed gas or
1.4 This standard does not purport to address all of the
ambient air passed through a desiccant to prevent contamina-
safety concerns, if any, associated with its use. It is the
tion from moisture present in the atmosphere.
responsibility of the user of this standard to establish appro-
4.4 Viscous samples can be analyzed by preheating them to
priate safety, health, and environmental practices and deter-
place them in a more fluid state allowing them to be drawn into
mine the applicability of regulatory limitations prior to use.
a syringe, or by dissolving them in a compatible anhydrous
1.5 This international standard was developed in accor-
solvent. Care should be taken to minimize time spent preheat-
dance with internationally recognized principles on standard-
ing samples to prevent moisture loss.
ization established in the Decision on Principles for the
Development of International Standards, Guides and Recom-
5. Significance and Use
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
5.1 Knowledge of the water content of lubricating oils,
additives, and similar products is important in the manufacture,
2. Referenced Documents
purchase, sale, transfer, or use of such petroleum products to
2
2.1 ASTM Standards: help in predicting their quality and performance characteristics.
D4175 Terminology Relating to Petroleum Products, Liquid
5.2 For lubricating oils, the presence of water can lead to
Fuels, and Lubricants
premature corrosion and wear, an increase in the debris load
resulting in diminished lubrication and premature plugging of
3. Terminology
filters, impedance to the effect of additives, and undesirable
3.1 Definitions:
support of deleterious bacterial growth.
6. Interferences
1
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
6.1 Methanol and acetonitrile are known to interfere with
Subcommittee D02.96.02 on Chemistry for the Evaluation of In-Service Lubricants.
the determination of moisture by this test method. These
Current edition approved Feb. 1, 2024. Published February 2024. Originally
substances contribute to a high bias in the final results. More
approved in 2009. Last previous edition approved in 2015 as D7546 – 15. DOI:
10.1520/D7546-24.
generally, some short-chained polar molecules mimic the effect
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
of water at the RH sensor resulting in a positive interference.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Strong polar solvents, such as n-methyl-pyrrolidone, can se-
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. verely damage the RH sensor.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Driv
...
This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D7546 − 15 D7546 − 24
Standard Test Method for
Determination of Moisture in New and In-Service Lubricating
1
Oils and Additives by Relative Humidity Sensor
This standard is issued under the fixed designation D7546; 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*
1.1 This test method covers the quantitative determination of water in new and in-service lubricating oils and additives in the range
of 10 mg/kg to 100 000 mg ⁄kg (0.001 wt. ⁄wt. to 10 % wt./wt.) using a relative humidity (RH) sensor. Methanol, acetonitrile, and
other compounds are known to interfere with this test method.
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 Warning—Samples tested in this test method can be flammable, explosive, and toxic. Use caution when handling them before
and after testing.
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 and healthsafety, health, and environmental practices and determine
the applicability of regulatory limitations prior to use.
1.5 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.
2. Referenced Documents
2
2.1 ASTM Standards:
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
3. Terminology
3.1 For definitions of terms used in this test method, refer to Terminology D4175.
3.1 Definitions:
3.1.1 For definitions of terms used in this test method, refer to Terminology D4175.
4. Summary of Test Method
4.1 An aliquot of sample is heated to a temperature between 25 °C to 200 °C with 1 °C resolution. The sample is maintained at
1
This test method is under the jurisdiction of ASTM Committee D02 on Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of Subcommittee
D02.96.02 on Chemistry for the Evaluation of In-Service Lubricants.
Current edition approved April 1, 2015Feb. 1, 2024. Published June 2015February 2024. Originally approved in 2009. Last previous edition approved in 20092015 as
D7546 – 09.D7546 – 15. DOI: 10.1520/D7546-15.10.1520/D7546-24.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1
---------------------- Page: 1 ----------------------
D7546 − 24
a constant temperature for the duration of the test. Dry inert gas flows over the heated sample and carries the thermally evolved
moisture past a relative humidity sensor. The sensor signal is integrated over time to provide a measurement of total mass of water
in the sample.
4.2 The sample injection may be done either by mass or by volume.
4.3 This test method utilizes anhydrous compressed gas or ambient air passed through a desiccant to prevent contamination from
moisture present in the atmosphere.
4.4 Viscous samples can be analyzed by preheating them to place them in a more fluid state allowing them to be drawn into a
syringe, or by dissolving them in a compatible anhydrous solvent. Care should be taken to minimize time spent preheating samples
to prevent moisture loss.
5. Significance and Use
5.1 Knowledge of the water content of lubricating oils, additives, and similar products is important in the manufacture, purchase,
sale, transfer, or use of such petroleum products to help in predicting their quality and performance characteristics.
5.2 For lubricating oils, the presence of water can lead to premature corrosion and wear, an increase in the debris load resulting
in diminished lubrication and premature plugging of filters, impedance to the effect of additives, and undesirable support of
deleterious bacterial growth.
6. In
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.