ASTM D2502-14(2019)e1

Standard Test Method for Estimation of Mean Relative Molecular Mass of Petroleum Oils from Viscosity Measurements

SIGNIFICANCE AND USE
4.1 This test method provides a means of calculating the mean relative molecular mass of petroleum oils from another physical measurement.  
4.2 Mean relative molecular mass is a fundamental physical constant that can be used in conjunction with other physical properties to characterize hydrocarbon mixtures.
SCOPE
1.1 This test method covers the estimation of the mean relative molecular mass of petroleum oils from kinematic viscosity measurements at 100 °F and 210 °F (37.78 °C and 98.89 °C).2 It is applicable to samples with mean relative molecular masses in the range from 250 to 700 and is intended for use with average petroleum fractions. It should not be applied indiscriminately to oils that represent extremes of composition or possess an exceptionally narrow mean relative molecular mass range.  
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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.  
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-2019
• ICS: 75.040 - Crude petroleum
• Technical Committee: D02 - Petroleum Products, Liquid Fuels, and Lubricants
• Drafting Committee: D02.04.0K - Correlative Methods

Relations

• Replaces: ASTM D2502-14(2019) - Standard Test Method for Estimation of Mean Relative Molecular Mass of Petroleum Oils from Viscosity Measurements
• Effective Date: 01-May-2019
• 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 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 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 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 D7042-12 - 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 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 D7042-11a - 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
• Refers: ASTM D445-06 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 15-May-2006
• Refers: ASTM D445-04e1 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and the Calculation of Dynamic Viscosity)
• Effective Date: 01-Nov-2004

Overview

ASTM D2502-14(2019)e1 – Standard Test Method for Estimation of Mean Relative Molecular Mass of Petroleum Oils from Viscosity Measurements provides standardized guidance for estimating the mean relative molecular mass (often called molar mass) of petroleum oils using kinematic viscosity measurements. Developed by ASTM International, this test method is widely recognized in the petroleum industry for its practicality and correlation with other essential petroleum characterizations. The applicability covers average petroleum fractions with mean molecular masses ranging from 250 to 700.

By determining the mean relative molecular mass, laboratories and refineries gain valuable information for product classification, quality control, and specification development. This standard aligns with internationally recognized principles set by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

Key Topics

• Kinematic Viscosity Measurement: The method requires measuring the kinematic viscosity of petroleum oil samples at two specified temperatures: 100 °F (37.78 °C) and 210 °F (98.89 °C), utilizing established procedures.
• H Function Calculation: A function, denoted as "H," is determined from the 100 °F viscosity value using tabulated data to facilitate the estimation process.
• Correlation Chart Use: The H value along with the 210 °F viscosity are plotted on a correlation chart, from which the mean relative molecular mass can be read directly.
• Applicable Range: Suitable for petroleum oil samples with average molecular masses between 250 and 700. The method is not recommended for materials with extreme or unusually narrow molecular mass distributions.
• Precision Statements: Details are provided on repeatability and reproducibility, ensuring reliability under typical laboratory conditions.
• Units: Measurements should be performed using inch-pound units, while SI units are included for reference.

Applications

The ASTM D2502-14(2019)e1 standard is vital for various sectors in the petroleum industry:

• Quality Control: Calculation of mean molecular mass assists in verifying product quality and consistency for lubricants and base oils.
• Product Characterization: Provides essential data when characterizing hydrocarbon mixtures, aiding formulators in understanding and differentiating between petroleum fractions.
• Specification Compliance: Ensures that products meet internal or regulatory specifications by providing a quick estimation method based on widely accessible viscosity tests.
• Laboratory Efficiency: Offers a practical alternative to more complex and expensive molecular mass determination methods, thus streamlining laboratory workflows.
• Blending and Formulation Guidance: Supports rational blending of oils by enabling the prediction of properties based on molecular mass information.

Related Standards

Organizations working with petroleum product analysis may find the following ASTM standards closely related and commonly referenced alongside ASTM D2502-14(2019)e1:

• ASTM D445 – Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity): The primary method for measuring kinematic viscosity, which is essential for D2502.
• ASTM D7042 – Standard Test Method for Dynamic Viscosity and Density of Liquids by Stabinger Viscometer (and the Calculation of Kinematic Viscosity): An alternative approach for precise viscosity measurement.
• ASTM Adjunct ADJD2502-E-PDF – Supporting material such as correlation charts for molecular mass estimation.
• Other Hydrocarbon Characterization Standards: Procedures related to density, boiling range distribution, and chemical composition analysis.

Keywords: mean relative molecular mass, kinematic viscosity, petroleum oils, ASTM D2502, viscosity measurement, hydrocarbon characterization, petroleum product specification.

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: D2502 − 14 (Reapproved 2019)
Standard Test Method for
Estimation of Mean Relative Molecular Mass of Petroleum
Oils from Viscosity Measurements
This standard is issued under the fixed designation D2502; 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.
ε NOTE—Editorially updated Footnote 4 in May 2020.
1. Scope D445 Test Method for Kinematic Viscosity of Transparent
and Opaque Liquids (and Calculation of Dynamic Viscos-
1.1 This test method covers the estimation of the mean
ity)
relative molecular mass of petroleum oils from kinematic
D7042 Test Method for Dynamic Viscosity and Density of
viscosity measurements at 100 °F and 210 °F (37.78 °C and
2 Liquids by Stabinger Viscometer (and the Calculation of
98.89 °C). It is applicable to samples with mean relative
Kinematic Viscosity)
molecular masses in the range from 250 to 700 and is intended
2.2 ASTM Adjuncts:
for use with average petroleum fractions. It should not be
Mean Relative Molecular Mass of Petroleum Oils from
applied indiscriminately to oils that represent extremes of
Viscosity Measurements
composition or possess an exceptionally narrow mean relative
molecular mass range.
3. Summary of Test Method
1.2 The values stated in inch-pound units are to be regarded
3.1 The kinematic viscosity of the oil is determined at
as standard. The values given in parentheses are mathematical
100 °F and 210 °F (37.78 °C and 98.89 °C).Afunction “H”of
conversions to SI units that are provided for information only
the 100 °F viscosity is established by reference to a tabulation
and are not considered standard.
of H function versus 100 °F viscosity. The H value and the
1.3 This standard does not purport to address all of the
210 °F viscosity are then used to estimate the mean relative
safety concerns, if any, associated with its use. It is the
molecular mass from a correlation chart.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
4. Significance and Use
mine the applicability of regulatory limitations prior to use.
4.1 This test method provides a means of calculating the
1.4 This international standard was developed in accor-
mean relative molecular mass of petroleum oils from another
dance with internationally recognized principles on standard-
physical measurement.
ization established in the Decision on Principles for the
4.2 Mean relative molecular mass is a fundamental physical
Development of International Standards, Guides and Recom-
constant that can be used in conjunction with other physical
mendations issued by the World Trade Organization Technical
properties to characterize hydrocarbon mixtures.
Barriers to Trade (TBT) Committee.
5. Procedure
2. Referenced Documents
5.1 Determine the kinematic viscosity of the oil at 100 °F
2.1 ASTM Standards:
and 210 °F (37.78 °C and 98.89 °C) as described in Test
Method D445 or Test Method D7042.
5.2 LookinTable1for100 °F(37.78 °C)viscosityandread
This test method is under the jurisdiction of ASTM Committee D02 on
Petroleum Products, Liquid Fuels, and Lubricants and is the direct responsibility of the value of H that corresponds to the measured viscosity.
Subcommittee D02.04.0K on Correlative Methods.
Linear interpolation between adjacent columns may be re-
Current edition approved May 1, 2019. Published June 2019. Originally
quired.
approved in 1966. Last previous edition approved in 2014 as D2502 – 14. DOI:
10.1520/D2502-14R19E01.
5.3 Read the viscosity-mean relative molecular mass chart
Hirschler, A. E., Journal of the Institute of Petroleum, JIPEA, Vol 32, 1946, p.
for H and 210 °F (98.89 °C) viscosity. A simplified version of
133.
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 Available from ASTM International Headquarters. Order Adjunct No.
the ASTM website. ADJD2502-E-PDF.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
D2502 − 14 (2019)
TABLE 1 Tabulation ofH Function
Kinematic
Viscosity,
H
cSt at 100 °F
(37.78 °C)
0 0.2 0.4 0.6 0.8
2 −178 −151 −126 −104 −85
3 −67 −52 −38 −25 −13
4 −1 9 19 28 36
544 52 59 66 73
6 79 85 90 96 101
7 106 111 116 120 124
8 128 132 136 140 144
9 147 151 154 157 160
10 163 166 169 172 175
11 178 180 183 185 188
12 190 192 195 197 199
13 201 203 206 208 210
14 211 213 215 217 219
15 221 222 224 226 227
16 229 231 232 234 235
17 237 238 240 241 243
18 244 245 247 248 249
19 251 252 253 255 256
20 257 258 259 261 262
21 263 264 265 266 267
22 269 270 271 272 273
23 274 275 276 277 278
24 279 280 281 281 282
25 283 284 285 286 287
26 288 289 289 290 291
27 292 293 294 294 295
28 296 297 298 298 299
29 300 301 301 302 303
30 304 304 305 306 306
31 307 308 308 309 310
32 310 311 312 312 313
33 314 314 315 316 316
34 317 317 318 319 319
35 320 320 321 322 322
36 323 323 324 325 325
37 326 326 327 327 328
38 328 329 329 330 331
39 331 332 332 333 333
H
0 1 2 3 4 5 678 9
40 334 336 339 341 343 345 347 349 352 354
50 355 357 359 361 363 364 366 368 369 371
60 372 374
...