ASTM D6203-22

Standard Test Method for Thermal Stability of Way Lubricants

SIGNIFICANCE AND USE
5.1 Thermal stability characterizes physical and chemical property changes which may adversely affect an oil's lubricating performance. This test method evaluates the thermal stability of a way lubricant in the presence of copper and steel rods at 100 °C. Deposits and rod colors are the evaluation criteria. No correlation of the test to field service has been made.  
5.2 This test method is intended for use in qualifying a way lubricant, rather than for quality control or condition monitoring purposes.
SCOPE
1.1 This test method covers the evaluation of the thermal stability of hydrocarbon-based way lubricants, although oxidation may occur during the test.  
1.2 The values stated in SI units are to be regarded as standard.  
1.2.1 Exception—The values given in parentheses 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
1.4 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

• Status: Published
• Publication Date: 31-Oct-2022
• ICS: 75.100 - Lubricants, industrial oils and related products
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.L0.01 - Metal Removal Fluids and Lubricants

Relations

• Refers: ASTM D4175-23a - Standard Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
• Effective Date: 15-Dec-2023
• Refers: ASTM D4175-23e1 - Standard Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
• Effective Date: 01-Jul-2023
• Refers: ASTM D4057-06(2011) - Standard Practice for Manual Sampling of Petroleum and Petroleum Products
• Effective Date: 01-Jun-2011
• Refers: ASTM D4057-95(2000) - Standard Practice for Manual Sampling of Petroleum and Petroleum Products
• Effective Date: 10-Apr-2000

Overview

ASTM D6203-22 is the internationally recognized Standard Test Method for Thermal Stability of Way Lubricants, published by ASTM International. This standard outlines a laboratory procedure for evaluating the thermal stability of hydrocarbon-based way lubricants when exposed to elevated temperatures in contact with copper and steel. The method assists manufacturers and users in qualifying new or reformulated way lubricants, providing critical information on the oil’s resistance to physical and chemical changes, such as deposit formation and metal discoloration, which could affect lubricating performance in industrial machinery.

This standardized procedure contributes to better lubricant performance by identifying products less likely to degrade under thermal stress, supporting reliability in machine operation and longevity of both lubricants and machine components.

Key Topics

• Thermal Stability Evaluation: The method assesses how hydrocarbon-based way lubricants maintain their properties at 100°C for a fixed period while in contact with copper and steel rods.
• Test Apparatus and Procedure:
  • A gravity convection oven maintains the temperature for 24 hours.
  • Copper (UNS C11000) and steel (AISI W1 1% carbon) rods are immersed in the lubricant sample.
  • After aging, rods and the beaker are evaluated for deposit formation and discoloration.
• Visual Assessment:
  • Discoloration of copper and steel rods is compared to a standardized color chart.
  • Deposits and etching are recorded to indicate signs of lubricant degradation.
• Use of Standardized Materials: The procedure utilizes specific grades of copper and steel, along with standardized cleaning and handling practices, ensuring reproducibility and comparability of results.

Applications

• Qualification of Way Lubricants: This test method is specifically intended for use in the initial qualification of new way lubricant formulations. It helps manufacturers demonstrate a lubricant’s ability to withstand high operating temperatures common in sliding surfaces of machine tools (ways and slides).
• Equipment Reliability: By identifying lubricants that exhibit minimum deposit formation and metal discoloration under heat, this standard supports better machinery performance and reduces the risk of failure due to lubricant breakdown.
• Research and Development: Laboratories use ASTM D6203-22 to benchmark new formulations and validate improvements in thermal stability, providing a critical tool for product development within the lubricants industry.
• Purchasing Specifications: Industrial users may reference this standard in procurement documents to ensure the lubricants they purchase meet an internationally recognized measure of thermal stability.

Related Standards

• ASTM D4057 - Practice for Manual Sampling of Petroleum and Petroleum Products: Supports representative sample collection for testing.
• ASTM D4175 - Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants: Supplies the precise terminology used in the test method.
• UNS C11000 Electrolytic Tough Pitch Copper and AISI W1 1% Carbon Steel: Material specifications referenced for the test specimens.
• Other ASTM Lubricant Standards:
  • ASTM D2272 - Test Method for Oxidation Stability of Steam Turbine Oils
  • ASTM D943 - Oxidation Characteristics of Inhibited Mineral Oils
  • ASTM D665 - Rust-Preventing Characteristics of Inhibited Mineral Oil

Keywords: ASTM D6203, way lubricants, thermal stability test, lubricant qualification, copper corrosion, steel corrosion, deposit formation, oil sludging, industrial lubricants, slideway lubricants

By adhering to ASTM D6203-22, lubricant manufacturers, equipment suppliers, and industrial users ensure consistency, reliability, and performance from their way lubricants in demanding applications, supporting operational efficiency and reducing maintenance costs.

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: D6203 − 22
Standard Test Method for
Thermal Stability of Way Lubricants
This standard is issued under the fixed designation D6203; 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. Terminology
1.1 This test method covers the evaluation of the thermal 3.1 Definitions:
stability of hydrocarbon-based way lubricants, although oxida-
3.1.1 For definitions of terms used in this test method, refer
tion may occur during the test.
to Terminology D4175.
1.2 The values stated in SI units are to be regarded as
4. Summary of Test Method
standard.
1.2.1 Exception—The values given in parentheses are for
4.1 Abeaker containing test oil and copper and steel rods is
information only.
placed in a gravity convection electric oven for 24 h at a test
1.3 This standard does not purport to address all of the
temperatureof100 °C.Atthecompletionofthetest,thecopper
safety concerns, if any, associated with its use. It is the
and steel rods are visually rated for discoloration and the
responsibility of the user of this standard to establish appro-
beaker is visually evaluated for deposits.
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
5. Significance and Use
1.4 This international standard was developed in accor-
5.1 Thermal stability characterizes physical and chemical
dance with internationally recognized principles on standard-
property changes which may adversely affect an oil’s lubricat-
ization established in the Decision on Principles for the
ing performance. This test method evaluates the thermal
Development of International Standards, Guides and Recom-
stability of a way lubricant in the presence of copper and steel
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee. rods at 100 °C. Deposits and rod colors are the evaluation
criteria. No correlation of the test to field service has been
made.
2. Referenced Documents
2.1 ASTM Standards:
5.2 This test method is intended for use in qualifying a way
D4057 Practice for Manual Sampling of Petroleum and
lubricant, rather than for quality control or condition monitor-
Petroleum Products
ing purposes.
D4175 Terminology Relating to Petroleum Products, Liquid
Fuels, and Lubricants
6. Apparatus
2.2 Other Standards:
6.1 Gravity Convection Electric Oven, capable of maintain-
UNS C11000 Electrolytic Tough Pitch Copper
ing the samples at a test temperature of 100 °C 6 2 °C.
AISI W1 1% Carbon Tool Steel
6.2 Calibrated Temperature Indicator, suitable for measur-
ing and controlling the oven temperature.
This test method is under the jurisdiction of ASTM Committee D02 on
6.3 Griffın Beakers, borosilicate glass, 100 mL.
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of
Subcommittee D02.L0.01 on Metal Removal Fluids and Lubricants.
6.4 Copper Test Specimens, in accordance with
Current edition approved Nov. 1, 2022. Published November 2022. Originally
UNS C11000, 99.9 % pure electrolytic tough pitch copper,
approved in 1997. Last previous edition approved in 2017 as D6203 – 17. DOI:
6.4 mm in diameter by 7.6 cm in length (0.25 in. by 3.0 in.).
10.1520/D6203-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
6.5 Steel Test Specimens, in accordance with AISI W1 1 %
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
carbon steel, 6.4 mm in diameter by 7.6 cm in length (0.25 in.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
by 3.0 in.).
Available from Copper Development Assoc., 2 Greenwich Office Park, Box
1840, Greenwich, CT 06836. 6.6 Silicon Carbide Abrasive, 320 grit with cloth backing.
Available from American Iron and Steel Institute (AISI), 1140 Connecticut
Ave., NW, Suite 705, Washington, DC 20036, http://www.steel.org. 6.7 Crocus Cloth.
*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
D6203 − 22
TABLE 1 Results of Interlaboratory Testing
Copper Rod Rating Steel Rod Rating Deposits (Y/N)
Cooperator: 3 4 5 6 3 4 5 6 3 4 5 6
Waylube:
A 1 221 11 11 N N N N
1 221 11 11 N N N N
B 5 535 11 11 N N N N
5 545 11 11 N N N N
C 3 342 11 11Y N N N
3 342 11 11Y N N N
D 3 352 11 11 N N N N
3 352 11 11 N N N N
6.8 Fives Cincinnati Color Chart. 9.5 Keep the oven doors closed during the entire test period.
6.9 Facial Tissue. 9.6 At the completion of 24 h, remove the beakers from the
oven and allow to cool to room temperature before proceeding.
7. Reagents
Continue within 2 h. Individually remove the rods from the oil
sample. Inspect for deposits clinging to the r
...

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: D6203 − 17 D6203 − 22
Standard Test Method for
Thermal Stability of Way Lubricants
This standard is issued under the fixed designation D6203; 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 evaluation of the thermal stability of hydrocarbon-based way lubricants, although oxidation may
occur during the test.
1.2 The values stated in SI units are to be regarded as standard.
1.2.1 Exception—The values given in parentheses 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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.4 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
2.1 ASTM Standards:
D4057 Practice for Manual Sampling of Petroleum and Petroleum Products
D4175 Terminology Relating to Petroleum Products, Liquid Fuels, and Lubricants
2.2 Other Standards:
UNS C11000 Electrolytic Tough Pitch Copper
AISI W1 1% Carbon Tool Steel
3. Terminology
3.1 Definitions:
3.1.1 For definitions of terms used in this test method, refer to Terminology D4175.
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.L0.01 on Metal Removal Fluids and Lubricants.
Current edition approved Dec. 1, 2017Nov. 1, 2022. Published March 2018November 2022. Originally approved in 1997. Last previous edition approved in 20122017
as D6203 – 06 (2012).D6203 – 17. DOI: 10.1520/D6203-17.10.1520/D6203-22.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from Copper Development Assoc., 2 Greenwich Office Park, Box 1840, Greenwich, CT 06836.
Available from American Iron and Steel Institute (AISI), 1140 Connecticut Ave., NW, Suite 705, Washington, DC 20036, http://www.steel.org.
*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
D6203 − 22
4. Summary of Test Method
4.1 A beaker containing test oil and copper and steel rods is placed in a gravity convection electric oven for 24 h at a test
temperature of 100 °C. At the completion of the test, the copper and steel rods are visually rated for discoloration and the beaker
is visually evaluated for deposits.
5. Significance and Use
5.1 Thermal stability characterizes physical and chemical property changes which may adversely affect an oil’s lubricating
performance. This test method evaluates the thermal stability of a way lubricant in the presence of copper and steel rods at 100 °C.
Deposits and rod colors are the evaluation criteria. No correlation of the test to field service has been made.
5.2 This test method is intended for use in qualifying a way lubricant, rather than for quality control or condition monitoring
purposes.
6. Apparatus
6.1 Gravity Convection Electric Oven, capable of maintaining the samples at a test temperature of 100 °C 6 2 °C.
6.2 Calibrated Temperature Indicator, suitable for measuring and controlling the oven temperature.
6.3 Griffın Beakers, borosilicate glass, 100 mL.
6.4 Copper Test Specimens, in accordance with UNS C11000, 99.9 % pure electrolytic tough pitch copper, 6.4 mm in diameter by
7.6 cm in length (0.25 in. by 3.0 in.).
6.5 Steel Test Specimens, in accordance with AISI W1 1 % carbon steel, 6.4 mm in diameter by 7.6 cm in length (0.25 in. by
3.0 in.).
6.6 Silicon Carbide Abrasive, 320 grit with cloth backing.
6.7 Crocus Cloth.
6.8 Fives Cincinnati Color Chart.
6.9 Facial Tissue.
7. Reagents
7.1 Reagent Grade Acetone. (Warning—Flammable, health hazard.)
7.2 Reagent Grade Heptane. (Warning—Flammable, health hazard.)
8. Preparation of Metal Rods
8.1 Handle the rods at all times using forceps, facial tissue, or suitable gloves.
8.2 Clean the iron and copper catalyst rods, whether new or previously used, prior to use. Clean the rods with the 320 grit silicon
carbide abrasive cloth while rotating the rods in a drill chuck at 1700 rev ⁄min to 1800 rev ⁄min. Clean the surface until it has a
bright copper or steel appearance. Discard rods when diameter is less than 6.2 mm.
The sole source of supply of the apparat
...