ASTM D341-20e1

Standard Practice for Viscosity-Temperature Equations and Charts for Liquid Petroleum or Hydrocarbon Products

ABSTRACT
This test method details the standard procedure for plotting viscosity-temperature charts that ascertain the kinematic viscosity of a petroleum oil or liquid hydrocarbon at any temperature within a limited range, provided that the kinematic viscosities at two temperatures are known.
SCOPE
1.1 This practice covers kinematic viscosity-temperature equations and charts (see Figs. 1-3), which are a convenient means to ascertain the kinematic viscosity of a petroleum oil or liquid hydrocarbon at any temperature within a limited range, provided that the kinematic viscosities at two temperatures are known.
FIG. 1 Facsimile of Kinematic Viscosity-Temperature Chart I High Range (Temperature in degrees Celsius)  
FIG. 2 Facsimile of Kinematic Viscosity-Temperature Chart I Medium Range (Temperature in degrees Celsius)  
FIG. 3 Facsimile of Kinematic Viscosity-Temperature Chart I Low Range (Temperature in degrees Celsius)  
1.2 The charts are designed to permit petroleum oil kinematic viscosity-temperature data to plot as a straight line. The charts have been derived from the equations shown in Section 5. The charts here presented provide a significant improvement in linearity over the charts previously available under Method D341 – 03. This increases the reliability of extrapolation to higher temperatures.  
1.3 The values provided in SI units are to be regarded as standard.  
1.3.1 Exception—The values given in parentheses are provided for information only.  
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: 30-Apr-2020
• ICS: 75.080 - Petroleum products in general
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.07 - Flow Properties

Relations

• Replaces: ASTM D341-20 - Standard Practice for Viscosity-Temperature Equations and Charts for Liquid Petroleum or Hydrocarbon Products
• Effective Date: 01-May-2020
• Refers: ASTM D445-24 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 01-Apr-2024
• Refers: ASTM D445-23 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 01-Nov-2023
• Refers: ASTM D445-16 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 15-Dec-2016
• Refers: ASTM D7279-14a - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids by Automated Houillon Viscometer
• Effective Date: 01-Oct-2014
• Refers: ASTM D445-14e1 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 01-Jul-2014
• Refers: ASTM D445-14 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 01-Jul-2014
• Refers: ASTM D7042-14 - Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity)
• Effective Date: 01-May-2014
• Refers: ASTM D7279-14 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids by Automated Houillon Viscometer
• Effective Date: 01-May-2014
• Refers: ASTM D7042-12a - Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity)
• Effective Date: 01-Nov-2012
• Refers: ASTM D445-12 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 15-Apr-2012
• Refers: ASTM D7042-12 - Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity)
• Effective Date: 15-Apr-2012
• Refers: ASTM D7042-12e1 - Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity)
• Effective Date: 15-Apr-2012
• Refers: ASTM D7042-11a - Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity)
• Effective Date: 01-Oct-2011
• Refers: ASTM D7042-10 - Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity)
• Effective Date: 01-Oct-2010

Overview

ASTM D341-20e1: Standard Practice for Viscosity-Temperature Equations and Charts for Liquid Petroleum or Hydrocarbon Products provides a standardized approach for determining the kinematic viscosity of petroleum oils and liquid hydrocarbons at various temperatures. By utilizing viscosity-temperature charts and equations, this practice enables professionals to predict fluid properties at any temperature within a defined range if kinematic viscosities at two known temperatures are available. This increases the reliability and ease of extrapolating viscosity data for quality control, product development, and process optimization in petroleum and chemical industries.

Key Topics

• Kinematic Viscosity-Temperature Relationship: The standard defines methods to plot and calculate kinematic viscosity as a function of temperature, typically using straight-line charts for specified liquid hydrocarbon ranges.
• Temperature Ranges: The provided charts (high, medium, and low ranges) cover kinematic viscosities from as low as 0.18 cSt up to 20,000,000 cSt, and temperatures from –70 °C to 370 °C, supporting diverse petroleum products.
• Standardized Equations: The document incorporates equations derived by MacCoull for robust characterization and linear plotting of viscosity-temperature data, enhancing accuracy in extrapolation and interpolation.
• Scope Limitations: The charts are intended for homogeneous hydrocarbon and petroleum-based liquids within the defined range - from the cloud point to the initial boiling point. Use with non-hydrocarbons or outside these limits can compromise accuracy.
• International Relevance: The standard is recognized worldwide, developed with strict adherence to international standardization principles, in line with WTO Technical Barriers to Trade (TBT) requirements.

Applications

ASTM D341-20e1 is widely applied across industries where prediction and control of fluid properties are critical, such as:

• Petroleum Refining and Blending: Enables operators to estimate viscosity changes due to temperature variations during refining or formulation of fuels, lubricants, and base oils.
• Quality Control: Supports laboratories in monitoring product consistency and compliance by allowing routine estimation of viscosity at any process-relevant temperature.
• Process and Equipment Design: Assists engineers in sizing pumps, pipelines, and heaters, ensuring fluid movement and handling are reliable under varying temperature conditions.
• Research and Product Development: Provides a basis for comparative studies and performance evaluation of new hydrocarbon formulations under simulated or real conditions.
• Regulatory Compliance: Facilitates reporting and certification processes by providing a recognized and reliable methodology for viscosity determination in petroleum and petrochemical sectors.

Related Standards

Several complementary ASTM standards are referenced and often used alongside ASTM D341-20e1 for comprehensive analysis of petroleum and hydrocarbon products:

• ASTM D445: Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• ASTM D7042: Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity)
• ASTM D7279: Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids by Automated Houillon Viscometer

These related standards cover sample measurements that can be used as the basis for plotting on viscosity-temperature charts as described in ASTM D341.

Practical Value

By following ASTM D341-20e1, laboratories and process engineers benefit from improved reliability in viscosity-temperature extrapolation, leading to better informed operational decisions, efficient process control, and enhanced product performance across a spectrum of hydrocarbon-based industries.

Keywords: viscosity-temperature charts, kinematic viscosity, petroleum products, hydrocarbon fluids, ASTM D341, viscosity prediction, process optimization, quality control.

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.
´1
Designation: D341 − 20
Standard Practice for
Viscosity-Temperature Equations and Charts for Liquid
Petroleum or Hydrocarbon Products
This standard is issued under the fixed designation D341; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
ε NOTE—Editorially removed adjunct information in August 2020.
multiple temperatures is applicable to D341. Some examples are given
1. Scope*
below.
1.1 This practice covers kinematic viscosity-temperature
D445 Test Method for Kinematic Viscosity of Transparent
equations and charts (see Figs. 1-3), which are a convenient
and Opaque Liquids (and Calculation of Dynamic Viscos-
means to ascertain the kinematic viscosity of a petroleum oil or
ity)
liquid hydrocarbon at any temperature within a limited range,
D7042 Test Method for Dynamic Viscosity and Density of
provided that the kinematic viscosities at two temperatures are
Liquids by Stabinger Viscometer (and the Calculation of
known.
Kinematic Viscosity)
1.2 The charts are designed to permit petroleum oil kine- D7279 Test Method for Kinematic Viscosity of Transparent
and Opaque Liquids by Automated Houillon Viscometer
matic viscosity-temperature data to plot as a straight line. The
charts have been derived from the equations shown in Section
3. Method Limitations
5.The charts here presented provide a significant improvement
in linearity over the charts previously available under Method
3.1 Warning—The charts should be used only in that range
D341 – 03. This increases the reliability of extrapolation to
inwhichthehydrocarbonorpetroleumfluidsarehomogeneous
higher temperatures.
liquids. The suggested range is thus between the cloud point at
low temperatures and the initial boiling point at higher tem-
1.3 The values provided in SI units are to be regarded as
peratures. The charts provide improved linearity in both low
standard.
kinematic viscosity and at temperatures up to 340 °C (approxi-
1.3.1 Exception—The values given in parentheses are pro-
mately 650 °F) or higher. Some high-boiling point materials
vided for information only.
can show a small deviation from a straight line as low as
1.4 This international standard was developed in accor-
280 °C (approximately 550 °F), depending on the individual
dance with internationally recognized principles on standard-
sample or accuracy of the data. Reliable data can be usefully
ization established in the Decision on Principles for the
plotted in the high temperature region even if it does exhibit
Development of International Standards, Guides and Recom-
some curvature. Extrapolations into such regions from lower
mendations issued by the World Trade Organization Technical
temperatures will lack accuracy, however. Experimental data
Barriers to Trade (TBT) Committee.
taken below the cloud point or temperature of crystal growth
will generally not be of reliable repeatability for interpolation
2. Referenced Documents
or extrapolation on the charts. It should also be emphasized
2.1 ASTM Standards:
that fluids other than hydrocarbons will usually not plot as a
straight line on these charts.
NOTE 1—Any ASTM standard that measures kinematic viscosity at
3.2 These charts are derived from the equations shown in
Section 5 and are applicable over the following ranges:
This practice is under the jurisdiction of ASTM Committee D02 on Petroleum
Fig. 1 0.30 cSt to 20 000 000 cSt and –70 °C to 370 °C
Products, Liquid Fuels, and Lubricants and are the direct responsibility of
Fig. 2 1.50 cSt to 200 000 cSt and –40 °C to 150 °C
Subcommittee D02.07 on Flow Properties.
Fig. 3 0.18 cSt to 7.0 cSt and –70 °C to 370 °C
Current edition approved May 1, 2020. Published June 2020. Originally
approved in 1932. Last previous edition approved in 2017 as D341 – 17. DOI:
4. Procedure for Use of the Charts
10.1520/D0341-20E01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
4.1 Plot two known kinematic viscosity-temperature points
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
onthechart.Drawasharplydefinedstraightlinethroughthem.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. A point on this line, within the range defined in Section 3,
*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
D341 − 20
FIG. 1 Facsimile of Kinematic Viscosity-Temperature Chart I High Range (Temperature in degrees Celsius)
´1
D341 − 20
FIG. 2 Facsimile of Kinematic Viscosity-Temperature Chart I Medium Range (Temperature in degrees Celsius)
´1
D341 − 20
FIG. 3 Facsimile of Kinematic Viscosity-Temperature Chart I Low Range (Temperature in degrees Celsius)
´1
D341 − 20
shows the kinematic viscosity at the corresponding desired 5.1.1 Inserting Eq 2 into Eq 1 will permit solving for the
temperature and vice versa. constants A and B. Once A and B are known, Z can be
calculated at any specified temperat
...