ASTM D2170/D2170M-24

Standard Test Method for Kinematic Viscosity of Asphalts

SIGNIFICANCE AND USE
5.1 The kinematic viscosity characterizes flow behavior. The method is used to determine the consistency of liquid asphalt as one element in establishing the uniformity of shipments or sources of supply. The specifications are usually at temperatures of 60 and 135 °C.
Note 3: The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar acceptable guideline provides a means of evaluating and controlling some of those factors.
SCOPE
1.1 This test method covers procedures for the determination of kinematic viscosity of liquid asphalts, road oils, and distillation residues of liquid asphalts all at 60 °C [140 °F] and of liquid asphalt binders at 135 °C [275 °F] (see table notes, 11.1) in the range from 6 to 100 000 mm2/s [cSt].  
1.2 Results of this test method can be used to calculate viscosity when the density of the test material at the test temperature is known or can be determined. See Annex A1 for the method of calculation.  
Note 1: This test method is suitable for use at other temperatures and at lower kinematic viscosities, but the precision is based on determinations on liquid asphalts and road oils at 60 °C [140 °F] and on asphalt binders at 135 °C [275 °F] only in the viscosity range from 30 to 6000 mm2/s [cSt].
Note 2: Modified asphalt binders or asphalt binders that have been conditioned or recovered are typically non-Newtonian under the conditions of this test. The viscosity determined from this method is under the assumption that asphalt binders behave as Newtonian fluids under the conditions of this test. When the flow is non-Newtonian in a capillary tube, the shear rate determined by this method may be invalid. The presence of non-Newtonian behavior for the test conditions can be verified by measuring the viscosity with viscometers having different-sized capillary tubes. The defined precision limits in 11.1 may not be applicable to non-Newtonian asphalt binders.  
1.3 Warning—Mercury has been designated by the United States Environmental Protection Agency (EPA) and many state agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury, or its vapor, may be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Material Safety Data Sheet (MSDS) or Safety Data Sheet (SDS) for details and the EPA’s website—http://www.epa.gov/mercury/faq.htm—for additional information. Users should be aware that selling mercury, mercury-containing products, or both, in your state may be prohibited by state law.  
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the standard.  
1.5 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes (excluding those in tables and figures) shall not be considered as requirements of the standard.  
1.6 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 ...

General Information

• Status: Published
• Publication Date: 30-Apr-2024
• ICS: 91.100.50 - Binders. Sealing materials
• ICS: 93.080.20 - Road construction materials
• Technical Committee: D04 - Road and Paving Materials
• Drafting Committee: D04.44 - Rheological Tests

Overview

ASTM D2170/D2170M-24 is the standardized test method for determining the kinematic viscosity of liquid asphalts, road oils, and distillation residues of liquid asphalts at 60 °C [140 °F] and for liquid asphalt binders at 135 °C [275 °F]. Published by ASTM International, this standard is essential in characterizing the flow behavior and consistency of asphalt materials, supporting quality control and specification compliance in the manufacture and supply of asphalt products. The established viscosity range for this method spans from 6 to 100,000 mm²/s (centistokes, cSt).

Key Topics

• Kinematic Viscosity Definition: Kinematic viscosity is defined as the resistance of a liquid to flow under gravity, measured as the ratio of dynamic viscosity to density. It is a crucial indicator of the flowability and workability of asphalt products.
• Temperature Specificity: The method specifies testing temperatures of 60 °C and 135 °C, which are standard for asphalt applications to ensure consistent and comparable results.
• Newtonian vs. Non-Newtonian Fluids: The test presumes that the asphalt behaves as a Newtonian fluid at the test conditions, important for accurate results. Modified asphalts may show non-Newtonian behavior, potentially impacting the validity of the results.
• Equipment and Procedures: Testing requires calibrated glass capillary viscometers or automated viscometers that mirror the manual method’s principles. Proper calibration and maintenance of equipment, as per ASTM D3666, are critical for reliable results.
• Precision and Repeatability: The standard provides criteria for single-operator and multi-laboratory precision to ensure reliable and repeatable viscosity measurements.
• Unit System: Results can be reported in either SI units (mm²/s) or inch-pound units (cSt), but units should not be mixed in a single set of results.

Applications

• Quality Control: Kinematic viscosity measurements are fundamental in assessing the consistency and uniformity of asphalt products across different shipments or sources, reducing the risk of variability in pavement construction.
• Specification Compliance: Asphalt suppliers and users employ this method to demonstrate compliance with regulatory and industry standards for asphalt binder performance at specified temperatures.
• Mix Design and Pavement Performance: Viscosity data informs the selection and design of asphalt mixes, directly affecting properties like compaction, mixing temperature, and long-term pavement durability.
• Process Optimization: Refineries and asphalt producers use kinematic viscosity values to monitor production processes and make real-time adjustments for enhanced product uniformity.
• Research and Development: Materials scientists and engineers use viscosity measurements for developing new asphalt formulations, especially for innovative paving solutions.

Related Standards

Several ASTM standards complement or support the use of ASTM D2170/D2170M-24:

• ASTM D445: Test Method for Kinematic Viscosity of Transparent and Opaque Liquids
• ASTM D446: Specifications and Operating Instructions for Glass Capillary Kinematic Viscometers
• ASTM D2493/D2493M: Viscosity-Temperature Chart for Asphalt Binders
• ASTM D3666: Minimum Requirements for Agencies Testing and Inspecting Road and Paving Materials
• ASTM D8055: Guide for Selecting an Appropriate Electronic Thermometer for Road and Paving Standards
• ASTM D341: Viscosity-Temperature Equations and Charts for Liquid Petroleum or Hydrocarbon Products

Keywords: kinematic viscosity, asphalt, ASTM D2170/D2170M, road oil, capillary viscometer, asphalt binder, viscosity test, quality control, pavement materials, asphalt consistency

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: D2170/D2170M − 24
Designation: 319/84 (89)
Standard Test Method for
Kinematic Viscosity of Asphalts
This standard is issued under the fixed designation D2170/D2170M; 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 that selling mercury, mercury-containing products, or both, in
your state may be prohibited by state law.
1.1 This test method covers procedures for the determina-
1.4 The values stated in either SI units or inch-pound units
tion of kinematic viscosity of liquid asphalts, road oils, and
are to be regarded separately as standard. The values stated in
distillation residues of liquid asphalts all at 60 °C [140 °F] and
each system may not be exact equivalents; therefore, each
of liquid asphalt binders at 135 °C [275 °F] (see table notes,
system shall be used independently of the other. Combining
11.1) in the range from 6 to 100 000 mm /s [cSt].
values from the two systems may result in nonconformance
1.2 Results of this test method can be used to calculate
with the standard.
viscosity when the density of the test material at the test
1.5 The text of this standard references notes and footnotes
temperature is known or can be determined. See Annex A1 for
that provide explanatory material. These notes and footnotes
the method of calculation.
(excluding those in tables and figures) shall not be considered
NOTE 1—This test method is suitable for use at other temperatures and
as requirements of the standard.
at lower kinematic viscosities, but the precision is based on determinations
1.6 This standard does not purport to address all of the
on liquid asphalts and road oils at 60 °C [140 °F] and on asphalt binders
at 135 °C [275 °F] only in the viscosity range from 30 to 6000 mm /s safety concerns, if any, associated with its use. It is the
[cSt].
responsibility of the user of this standard to establish appro-
NOTE 2—Modified asphalt binders or asphalt binders that have been
priate safety, health, and environmental practices and deter-
conditioned or recovered are typically non-Newtonian under the condi-
mine the applicability of regulatory limitations prior to use.
tions of this test. The viscosity determined from this method is under the
1.7 This international standard was developed in accor-
assumption that asphalt binders behave as Newtonian fluids under the
conditions of this test. When the flow is non-Newtonian in a capillary dance with internationally recognized principles on standard-
tube, the shear rate determined by this method may be invalid. The
ization established in the Decision on Principles for the
presence of non-Newtonian behavior for the test conditions can be verified
Development of International Standards, Guides and Recom-
by measuring the viscosity with viscometers having different-sized cap-
mendations issued by the World Trade Organization Technical
illary tubes. The defined precision limits in 11.1 may not be applicable to
Barriers to Trade (TBT) Committee.
non-Newtonian asphalt binders.
1.3 Warning—Mercury has been designated by the United
2. Referenced Documents
States Environmental Protection Agency (EPA) and many state
2.1 ASTM Standards:
agencies as a hazardous material that can cause central nervous
C670 Practice for Preparing Precision and Bias Statements
system, kidney, and liver damage. Mercury, or its vapor, may
for Test Methods for Construction Materials
be hazardous to health and corrosive to materials. Caution
D8 Terminology Relating to Materials for Roads and Pave-
should be taken when handling mercury and mercury-
ments
containing products. See the applicable product Material
D92 Test Method for Flash and Fire Points by Cleveland
Safety Data Sheet (MSDS) or Safety Data Sheet (SDS) for
Open Cup Tester
details and the EPA’s website—http://www.epa.gov/mercury/
D341 Practice for Viscosity-Temperature Equations and
faq.htm—for additional information. Users should be aware
Charts for Liquid Petroleum or Hydrocarbon Products
D445 Test Method for Kinematic Viscosity of Transparent
and Opaque Liquids (and Calculation of Dynamic Viscos-
This test method is under the jurisdiction of ASTM Committee D04 on Road
ity)
and Paving Materials and is the direct responsibility of Subcommittee D04.44 on
Rheological Tests. In the IP this test method is under the jurisdiction of the
Standardization Committee. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Current edition approved May 1, 2024. Published May 2024. Originally contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
approved in 1963. Last previous edition approved in 2022 as D2170/D2170M – 22. Standards volume information, refer to the standard’s Document Summary page on
DOI: 10.1520/D2170_D2170M-24. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D2170/D2170M − 24
D446 Specifications and Operating Instructions for Glass resistance to flow of a liquid. It is commonly called the
Capillary Kinematic Viscometers viscosity of the liquid. The cgs unit of viscosity is 1 g/cm·s
D2162 Practice for Basic Calibration of Master Viscometers (1 dyne·s ⁄cm ) and is called a poise (P). The SI unit of
and Viscosity Oil Standards viscosity is 1 Pa·s (1 N·s/m ) and is called a Pascal-second.
D2493/D2493M Practice for Viscosity-Temperature Chart One Pa·s is equivalent to 10 P.
for Asphalt Binders
3.2 For definitions of other terms used in this standard, refer
D3666 Specification for Minimum Requirements for Agen-
to Terminology D8.
cies Testing and Inspecting Road and Paving Materials
4. Summary of Test Method
D8055 Guide for Selecting an Appropriate Electronic Ther-
mometer for Replacing Mercury Thermometers in D04
4.1 The time is measured for a fixed volume of the liquid to
Road and Paving Standards
flow through the capillary of a calibrated glass capillary
E1 Specification for ASTM Liquid-in-Glass Thermometers
viscometer under an accurately reproducible head and at a
E77 Test Method for Inspection and Verification of Ther-
closely controlled temperature. The kinematic viscosity is then
mometers
calculated by multiplying the efflux time in seconds by the
E691 Practice for Conducting an Interlaboratory Study to
viscometer calibration factor.
Determine the Precision of a Test Method
5. Significance and Use
E879 Specification for Thermistor Sensors for General Pur-
pose and Laboratory Temperature Measurements
5.1 The kinematic viscosity characterizes flow behavior.
E1137/E1137M Specification for Industrial Platinum Resis-
The method is used to determine the consistency of liquid
tance Thermometers
asphalt as one element in establishing the uniformity of
shipments or sources of supply. The specifications are usually
3. Terminology
at temperatures of 60 and 135 °C.
3.1 Definitions of Terms Specific to This Standard:
NOTE 3—The quality of the results produced by this standard are
3.1.1 automated viscometer, n—apparatus which, in part or dependent on the competence of the personnel performing the procedure
and the capability, calibration, and maintenance of the equipment used.
in whole, has mechanized one or more of the procedural steps
Agencies that meet the criteria of Specification D3666 are generally
indicated in Section 8 without changing the principle or
considered capable of competent and objective testing, sampling,
technique of the basic manual apparatus.
inspection, etc. Users of this standard are cautioned that compliance with
3.1.1.1 Discussion—The essential elements of the apparatus
Specification D3666 alone does not completely ensure reliable results.
in respect to dimensions, design, or operational characteristics Reliable results depend on many factors; following the suggestions of
Specification D3666 or some similar acceptable guideline provides a
are the same as those of the manual method. Apparatus which
means of evaluating and controlling some of those factors.
determine kinematic viscosity by physical techniques that are
different than those used in this test method are not considered
6. Apparatus
to be automated viscometers.
6.1 Viscometers, capillary-type, made of borosilicate glass,
3.1.1.2 Discussion—Automated viscometers do not need to
annealed, suitable for this test are described in Annex A2 and
be reverse-flow type provided that the sensors (thermal, NIR,
include the following:
capacitive, other) used for sensing the meniscus of the sample
6.1.1 Cannon-Fenske viscometer for opaque liquids.
can accurately detect an opaque sample.
6.1.2 Zeitfuchs Cross-Arm viscometer.
3.1.2 density, n—the mass per unit volume of liquid. The SI
6.1.3 Lantz-Zeitfuchs viscometer.
3 3
unit of density is 1 kg/m . The cgs unit of density is 1 g/cm .
6.1.4 BS U-Tube modified reverse-flow viscometer.
6.1.5 Calibrated viscometers are available from commercial
3.1.3 kinematic viscosity, n—the ratio of the viscosity to the
suppliers. Details regarding calibration of viscometers are
density of a liquid, measured as the resistance to flow of a
given in Annex A3.
liquid under gravity.
6.1.6 Automated Viscometers—Automated apparatus may
3.1.3.1 Discussion—The SI unit of kinematic viscosity is
2 2
be used if they duplicate the physical conditions, operations, or
m /s; for practical use, a submultiple (mm /s) is more conve-
processes of the manual apparatus. Any viscometer, tempera-
nient. The cgs unit of kinematic viscosity is 1 cm /s and is
−2
ture measuring device, temperature control, and temperature-
called a stoke (symbol St). The centistoke (1 cSt = 10 St) is
controlled bath or timing device incorporated in the automated
1 mm /s and is often used.
apparatus shall conform to the specification for these compo-
3.1.4 Newtonian viscosity, n—the viscosity of a liquid that is
nents as stated in Section 6 of this test method. Flow times of
shear-rate independent in which the rate of shear is linearly
less than 200 s are permitted; however, a kinetic energy
proportional to the shearing stress.
correction shall be calculated and applied in accordance with
3.1.5 non-Newtonian viscosity, n—the viscosity of a liquid
Section 7 on Kinematic Viscosity Calculation of Specification
that is shear-rate dependent in which the rate of shear is not
D446. The kinetic energy correction shall not exceed 3.0 % of
linearly proportional to the shearing stress.
the measured viscosity. The automated apparatus shall be
3.1.6 viscosity (coeffıcient of), n—the ratio between the
capable of determining kinematic viscosity of a viscosity oil
applied shear stress and rate of shear is called the coefficient of standard (see A3.2.1) within the limits stated in Table 1. The
viscosity.
precision shall be of statistical equivalence to or better (has less
3.1.6.1 Discussion—This coefficient is a measure of the variability) than the manual apparatus.
D2170/D2170M − 24
point is determined in accordance with Test Method D92.
6.2 Thermometers—Calibrated thermometers with suitable
range and estimated measurement uncertainty of 0.02 °C
6.4 Timer—A stopwatch or other timing device, graduated
[0.04 °F] or less at 95 % confidence interval listed on the
in divisions of 0.1 s or less and accurate to within 0.05 % when
calibration certificate and is one of the following:
tested over intervals of not less than 15 min. Timing devices for
6.2.1 A liquid-in-glass thermometer that is calibrated annu-
this test method must be standardized at least every twelve
ally. The calibration shall be verified at the ice point in
months.
accordance with Appendix X1. ASTM Kinematic Viscosity
6.4.1 Electrical Timing Devices may be used only on
Thermometers 47C and 47F conforming to Specification E1,
electrical circuits, the frequencies of which are controlled to an
and IP 35C and 35F are suitable for use at 60 °C [140 °F], and
accuracy of 0.05 % or better.
ASTM Kinematic Viscosity Thermometers 110C and 110F are
6.4.1.1 Alternating currents, the frequencies of which are
suitable for use at 135 °C [275 °F].
intermittently and not continuously controlled, as provided by
some public power systems, can cause large errors, particularly
NOTE 4—The specified thermometers in 6.2.1 are standardized as “total
over short timing intervals, when used to actuate electrical
immersion” thermometers, which are designed to indicate temperatures
correctly when just that portion of the thermometer containing the liquid
timing devices.
is exposed to the temperature being measured and the remainder of the
stem and expansion chamber at the top of the thermometer exposed to the
7. Preparation of Sample
room temperature. The practice of completely submerging the thermom-
eter is not recommended. When a “total immersion” thermometer is
7.1 To minimize loss of volatile constituents and to obtain
completely submerged, corrections for each individual thermometer based
reproducible results, proceed as follows:
on calibration under conditions of complete submergence should be
7.1.1 Procedure for Liquid Asphalts, Distillation Residues,
determined and applied. If the thermometer is completely submerged in
and Road Oil:
the bath during use, the pressure of the gas in the expansion chamber will
7.1.1.1 Allow sealed samples, as received, to reach room
be higher or lower than during standardization and may cause high or low
readings on the thermometer.
temperature.
7.1.1.2 Open the sample container and mix the sample
6.2.2 A platinum resistance thermometer (PRT) with a
thoroughly by stirring for 30 s, taking care to avoid the
sensor which conforms to the requirements of Specification
entrapment of air. If the sample is too viscous for such stirring,
E1137/E1137M. The thermometer shall be calibrated annually
place the sample in the tightly sealed container in a bath or
as a single unit and have a three- or four-wire connection
oven maintained at 63 6 3 °C [145 6 5 °F] until it becomes
configuration. The sensing element shall be immersed to the
sufficiently liquid for stirring.
depth specified by the manufacturer adjacent to the capillary
7.1.1.3 Immediately charge the viscometer, or, if the test is
tube.
to be made at a later time, pour approximately 20 mL into one
NOTE 5—A minimum of 50 mm [2 in.] of the thermometer sheath
or more clean, dry containers having a capacity of approxi-
(wire-connecting side) should not be subjected to the bath medium unless
mately 30 mL and immediately seal with an airtight closure.
otherwise specified by the manufacturer.
7.1.1.4 For materials with kinematic viscosities at 60 °C
6.2.3 A thermistor thermometer with sensor, which con- 2
[140 °F] above 800 mm /s [cSt], heat the 20 mL sample in the
forms to the requirements of Specification E879, calibrated
sealed container in an oven or bath maintained at 63 6 3 °C
annually as a single unit. The sensing element of the thermistor
[145 6 5 °F] until it is sufficiently liquid for a convenient
shall be completely immersed in the bath adjacent to the
transfer into the viscometer. Such heating should not exceed
capillary tube.
30 min.
6.2.3.1 Thermistor thermometers used with testing tempera-
7.1.2 Procedure for Liquid Asphalts and Distillation Resi-
tures greater than 100 °C shall be standardized as a single unit
dues in the Range from 6 to 100 000 mm /s [cSt]:
every three months.
7.1.2.1 Heat the sample with care to prevent local overheat-
ing until it has become sufficiently fluid to pour, occasionally
NOTE 6—The use of the thermometric devices specified in 6.2.2 and
stirring the sample to aid heat transfer and to ensure uniformity.
6.2.3 are understood to introduce bias in the precision in this method.
Also, see Guide D8055 for further guidance for appropriate sensor types.
7.1.2.2 Transfer a minimum of 20 mL into a suitable
container and heat to 135 6 5.5 °C [275 6 10 °F], stirring
6.3 Bath—A bath suitable for immersion of the viscometer
occasionally to prevent local overheating and taking care to
so that the liquid reservoir or the top of the capillary, whichever
avoid the entrapment of air.
is uppermost, is at least 20 mm below the upper bath level, and
with provisions for visibility of the viscometer and the ther-
8. Procedure
mometer. Firm supports for the viscometer shall be provided,
or the viscometer may be an integral part of the bath. The
8.1 The specific details of operation vary somewhat for the
efficiency of the stirring and the balance between heat losses
various types of viscometers. See the detailed descriptions of
and heat input must be such that the temperature of the bath
viscometers in Annex A2 for instructions for using the type of
medium does not vary by more than 60.03 °C [60.05 °F] over
viscometer selected. In all cases, however, follow the general
the length of the viscometer, or from viscometer to viscometer
procedure described in 8.2 – 8.8.
in the various bath positions at 60 °C [140 °F].
8.1.1 The specific details of operation for automated vis-
cometers will vary from the manual procedure described in 8.4,
NOTE 7—Distilled water is a suitable bath liquid for determinations at
8.6, and 8.8. Refer to the operating instructions provided by the
60 °C [140 °F]. USP White Oil with a flash point above 215 °C [420 °F]
has been found suitable for determinations at 135 °C [275 °F]. The flash automated viscometer manufacturer.
D2170/D2170M − 24
8.2 Maintain the bath at the test temperature within 10. Report
60.01 °C [60.02 °F]. Apply the necessary corrections, if any,
10.1 Always report the test temperature with the result, for
to all thermometer readings.
example:
8.3 Select a clean, dry viscometer which will give an efflux
Kinematic viscosity at 60 °C 5 75.6 mm /s cSt (2)
@ #
time greater than 60 s and preheat to test temperature.
11. Precision and Bias
8.4 Charge the viscometer in the manner dictated by the
11.1 Criteria for judging the acceptability of viscosity test
design of the instrument, as prescribed in Annex A2.
results obtained by this method are given in Tables 1 and 2.
8.5 Allow the charged viscometer to remain in the bath long
enough to reach the test temperature, as prescribed in Annex
TABLE 1 Acceptability of Test Results for Kinematic Viscosity for
A
A2.
Liquid Asphalts at 60 °C
NOTE 1—The values given in Column 2 are the coefficients of variation
8.6 Start the flow of asphalt in the viscometer as prescribed
that have been found to be appropriate for the materials and conditions of
in Annex A2.
test described in Column 1. The values given in Column 3 are the limits
that should not be exceeded by the difference between the results of two
8.7 Measure to within 0.1 s the time required for the leading
properly conducted tests.
edge of the meniscus to pass from the first timing mark to the
Acceptable
second. If this efflux time is less than 60 s, select a viscometer
Coefficient of
Range of
Material and Type Index Variation
of smaller capillary diameter and repeat the operation.
Two Results
B
(% of mean)
B
(% of mean)
8.8 Upon completion of the test, clean the viscometer
Single-operator precision:
thoroughly by several rinsings with an appropriate solvent
Liquid asphalts at 60 °C [140 °F]:
completely miscible with the sample, followed by a completely
below 3000 mm /s [cSt] 0.53 1.5
3000 to 6000 mm /s [cSt] 0.71 2.0
volatile solvent. Dry the tube by passing a slow stream of
6000 mm /s [cSt] and above 3.2 8.9
filtered dried air through the capillary for 2 min, or until the last
Multilaboratory precision:
trace of solvent is removed. Alternatively, the viscometer may Liquid asphalts at 60 °C [140 °F]:
below 3000 mm /s [cSt] 1.06 3.0
be cleaned in a glass cleaning oven at a temperature not to
2 C
3000 to 6000 mm /s [cSt] 3.11 9.0
exceed 500 °C [932 °F], followed by rinses with distilled or 2 C
above 6000 mm /s [cSt] 3.6 10.0
deionized water, residue-free acetone, and filtered dry air.
A
Supporting data and information for determining these estimates can be found in
Periodically, if deposits are observed, clean the instrument with
Manning, R. E., “Comments on Vacuum Viscometers for Measuring the Viscosity
of Asphalt Cements,” Symposium on Fundamental Viscosity of Bituminous
a strong acid cleaning solution to remove organic deposits,
Materials, ASTM STP 328, ASTM International, 1963, pp. 44–47.
rinse thoroughly with distilled water and residue-free acetone,
B
These numbers represent, respectively, the (1s %) and (d2s %) limits as
and dry with filtered dry air.
described in Practice C670.
C
Based on less than 30 degrees of freedom.
NOTE 8—The cleaning oven may burn off the glue that connects the
viscometer tube to the holder.
TABLE 2 Acceptability of Test Results for Kinematic Viscosity for
8.8.1 Chromic acid cleaning solution may be prepared by
Liquid Asphalts at 135 °C
adding, with the usual precautions, 800 mL of concentrated
NOTE 1—The values given in Column 2 are the coefficients of variation
sulphuric acid to a solution of 92 g of sodium dichromate in
that have been found to be appropriate for the materials and conditions of
458 mL of water. The use of similar commercially available
test described in Column 1. The values given in Column 3 are the limits
sulphuric acid cleaning solutions is acceptable. Nonchromium-
that should not be exceeded by the difference between the results of two
containing, strongly oxidizing acid cleaning solutions may be
properly conducted tests.
substituted so as to avoid the disposal problems of chromium-
Acceptable
Coefficient of
containing solutions.
...

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: D2170/D2170M − 22 D2170/D2170M − 24
Designation: 319/84 (89)
Standard Test Method for
Kinematic Viscosity of Asphalts
This standard is issued under the fixed designation D2170/D2170M; 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 procedures for the determination of kinematic viscosity of liquid asphalts, road oils, and distillation
residues of liquid asphalts all at 60 °C [140 °F] and of liquid asphalt binders at 135 °C [275 °F] (see table notes, 11.1) in the range
from 6 to 100 000 mm /s [cSt].
1.2 Results of this test method can be used to calculate viscosity when the density of the test material at the test temperature is
known or can be determined. See Annex A1 for the method of calculation.
NOTE 1—This test method is suitable for use at other temperatures and at lower kinematic viscosities, but the precision is based on determinations on
liquid asphalts and road oils at 60 °C [140 °F] and on asphalt binders at 135 °C [275 °F] only in the viscosity range from 30 to 6000 mm /s [cSt].
NOTE 2—Modified asphalt binders or asphalt binders that have been conditioned or recovered are typically non-Newtonian under the conditions of this
test. The viscosity determined from this method is under the assumption that asphalt binders behave as Newtonian fluids under the conditions of this test.
When the flow is non-Newtonian in a capillary tube, the shear rate determined by this method may be invalid. The presence of non-Newtonian behavior
for the test conditions can be verified by measuring the viscosity with viscometers having different-sized capillary tubes. The defined precision limits in
11.1 may not be applicable to non-Newtonian asphalt binders.
1.3 Warning—Mercury has been designated by the United States Environmental Protection Agency (EPA) and many state
agencies as a hazardous material that can cause central nervous system, kidney, and liver damage. Mercury, or its vapor, may be
hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products.
See the applicable product Material Safety Data Sheet (MSDS) or Safety Data Sheet (SDS) for details and the EPA’s
website—http://www.epa.gov/mercury/faq.htm—for additional information. Users should be aware that selling mercury, mercury-
containing products, or both, in your state may be prohibited by state law.
1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in nonconformance with the standard.
1.5 The text of this standard references notes and footnotes that provide explanatory material. These notes and footnotes
(excluding those in tables and figures) shall not be considered as requirements of the standard.
This test method is under the jurisdiction of ASTM Committee D04 on Road and Paving Materials and is the direct responsibility of Subcommittee D04.44 on Rheological
Tests. In the IP this test method is under the jurisdiction of the Standardization Committee.
Current edition approved Nov. 1, 2022May 1, 2024. Published November 2022May 2024. Originally approved in 1963. Last previous edition approved in 20182022 as
D2170/D2170M – 18.D2170/D2170M – 22. DOI: 10.1520/D2170_D2170M-22.10.1520/D2170_D2170M-24.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D2170/D2170M − 24
1.6 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.
1.7 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:
C670 Practice for Preparing Precision and Bias Statements for Test Methods for Construction Materials
D8 Terminology Relating to Materials for Roads and Pavements
D92 Test Method for Flash and Fire Points by Cleveland Open Cup Tester
D341 Practice for Viscosity-Temperature Equations and Charts for Liquid Petroleum or Hydrocarbon Products
D445 Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
D446 Specifications and Operating Instructions for Glass Capillary Kinematic Viscometers
D2162 Practice for Basic Calibration of Master Viscometers and Viscosity Oil Standards
D2493/D2493M Practice for Viscosity-Temperature Chart for Asphalt Binders
D3666 Specification for Minimum Requirements for Agencies Testing and Inspecting Road and Paving Materials
D8055 Guide for Selecting an Appropriate Electronic Thermometer for Replacing Mercury Thermometers in D04 Road and
Paving Standards
E1 Specification for ASTM Liquid-in-Glass Thermometers
E77 Test Method for Inspection and Verification of Thermometers
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E879 Specification for Thermistor Sensors for General Purpose and Laboratory Temperature Measurements
E1137/E1137M Specification for Industrial Platinum Resistance Thermometers
3. Terminology
3.1 Definitions of Terms Specific to This Standard:
3.1.1 automated viscometer, n—apparatus which, in part or in whole, has mechanized one or more of the procedural steps indicated
in Section 8 without changing the principle or technique of the basic manual apparatus.
3.1.1.1 Discussion—
The essential elements of the apparatus in respect to dimensions, design, or operational characteristics are the same as those of the
manual method. Apparatus which determine kinematic viscosity by physical techniques that are different than those used in this
test method are not considered to be automated viscometers.
3.1.1.2 Discussion—
Automated viscometers do not need to be reverse-flow type provided that the sensors (thermal, NIR, capacitive, other) used for
sensing the meniscus of the sample can accurately detect an opaque sample.
3 3
3.1.2 density, n—the mass per unit volume of liquid. The SI unit of density is 1 kg/m . The cgs unit of density is 1 g/cm .
3.1.3 kinematic viscosity, n—the ratio of the viscosity to the density of a liquid, measured as the resistance to flow of a liquid under
gravity.
3.1.3.1 Discussion—
2 2
The SI unit of kinematic viscosity is m /s; for practical use, a submultiple (mm /s) is more convenient. The cgs unit of kinematic
2 −2 2
viscosity is 1 cm /s and is called a stoke (symbol St). The centistoke (1 cSt = 10 St) is 1 mm /s and is often used.
3.1.4 Newtonian viscosity, n—the viscosity of a liquid that is shear-rate independent in which the rate of shear is linearly
proportional to the shearing stress.
3.1.5 non-Newtonian viscosity, n—the viscosity of a liquid that is shear-rate dependent in which the rate of shear is not linearly
proportional to the shearing stress.
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.
D2170/D2170M − 24
3.1.5 road oil, n—a slow-curing, petroleum-derived liquid used to control dust or act as a waterproofing sealant.
3.1.6 viscosity (coeffıcient of), n—the ratio between the applied shear stress and rate of shear is called the coefficient of viscosity.
3.1.6.1 Discussion—
This coefficient is a measure of the resistance to flow of a liquid. It is commonly called the viscosity of the liquid. The cgs unit
2 2
of viscosity is 1 g/cm·s (1 dyne·s ⁄cm ) and is called a poise (P). The SI unit of viscosity is 1 Pa·s (1 N·s/m ) and is called a
Pascal-second. One Pa·s is equivalent to 10 P.
3.2 For definitions of other terms used in this standard, refer to Terminology D8.
4. Summary of Test Method
4.1 The time is measured for a fixed volume of the liquid to flow through the capillary of a calibrated glass capillary viscometer
under an accurately reproducible head and at a closely controlled temperature. The kinematic viscosity is then calculated by
multiplying the efflux time in seconds by the viscometer calibration factor.
5. Significance and Use
5.1 The kinematic viscosity characterizes flow behavior. The method is used to determine the consistency of liquid asphalt as one
element in establishing the uniformity of shipments or sources of supply. The specifications are usually at temperatures of 60 and
135 °C.
NOTE 3—The quality of the results produced by this standard are dependent on the competence of the personnel performing the procedure and the
capability, calibration, and maintenance of the equipment used. Agencies that meet the criteria of Specification D3666 are generally considered capable
of competent and objective testing, sampling, inspection, etc. Users of this standard are cautioned that compliance with Specification D3666 alone does
not completely ensure reliable results. Reliable results depend on many factors; following the suggestions of Specification D3666 or some similar
acceptable guideline provides a means of evaluating and controlling some of those factors.
6. Apparatus
6.1 Viscometers, capillary-type, made of borosilicate glass, annealed, suitable for this test are described in Annex A2 and include
the following:
6.1.1 Cannon-Fenske viscometer for opaque liquids.
6.1.2 Zeitfuchs Cross-Arm viscometer.
6.1.3 Lantz-Zeitfuchs viscometer.
6.1.4 BS U-Tube modified reverse-flow viscometer.
6.1.5 Calibrated viscometers are available from commercial suppliers. Details regarding calibration of viscometers are given in
Annex A3.
6.1.6 Automated Viscometers—Automated apparatus may be used if they duplicate the physical conditions, operations, or
processes of the manual apparatus. Any viscometer, temperature measuring device, temperature control, and temperature-
controlled bath or timing device incorporated in the automated apparatus shall conform to the specification for these components
as stated in Section 6 of this test method. Flow times of less than 200 s are permitted; however, a kinetic energy correction shall
be calculated and applied in accordance with Section 7 on Kinematic Viscosity Calculation of Specification D446. The kinetic
energy correction shall not exceed 3.0 % of the measured viscosity. The automated apparatus shall be capable of determining
kinematic viscosity of a viscosity oil standard (see A3.2.1) within the limits stated in Table 1. The precision shall be of statistical
equivalence to or better (has less variability) than the manual apparatus.
6.2 Thermometers—Calibrated thermometers with suitable range and estimated measurement uncertainty of 0.02 °C [0.04 °F] or
less at 95 % confidence interval listed on the calibration certificate and is one of the following:
6.2.1 A liquid-in-glass thermometer that is calibrated annually. The calibration shall be verified at the ice point in accordance with
D2170/D2170M − 24
Appendix X1. ASTM Kinematic Viscosity Thermometers 47C and 47F conforming to Specification E1, and IP 35C and 35F are
suitable for use at 60 °C [140 °F], and ASTM Kinematic Viscosity Thermometers 110C and 110F are suitable for use at 135 °C
[275 °F].
NOTE 4—The specified thermometers in 6.2.1 are standardized as “total immersion” thermometers, which are designed to indicate temperatures correctly
when just that portion of the thermometer containing the liquid is exposed to the temperature being measured and the remainder of the stem and expansion
chamber at the top of the thermometer exposed to the room temperature. The practice of completely submerging the thermometer is not recommended.
When a “total immersion” thermometer is completely submerged, corrections for each individual thermometer based on calibration under conditions of
complete submergence mustshould be determined and applied. If the thermometer is completely submerged in the bath during use, the pressure of the
gas in the expansion chamber will be higher or lower than during standardization,standardization and may cause high or low readings on the thermometer.
6.2.2 A platinum resistance thermometer (PRT) with a sensor which conforms to the requirements of Specification E1137/
E1137M. The thermometer shall be calibrated annually as a single unit and have a three- or four-wire connection configuration.
The sensing element shall be immersed to the depth specified by the manufacturer adjacent to the capillary tube.
NOTE 5—A minimum of 50 mm [2 in.] of the thermometer sheath (wire-connecting side) shallshould not be subjected to the bath medium unless otherwise
specified by the manufacturer.
6.2.3 A thermistor thermometer with sensor, which conforms to the requirements of Specification E879, calibrated annually as a
single unit. The sensing element of the thermistor shall be completely immersed in the bath adjacent to the capillary tube.
6.2.3.1 Thermistor thermometers used with testing temperatures greater than 100 °C shall be standardized as a single unit every
three months.
NOTE 6—The use of the thermometric devices specified in 6.2.2 and 6.2.3 are understood to introduce bias in the precision in this method. Also, see Guide
D8055 for further guidance for appropriate sensor types.
6.3 Bath—A bath suitable for immersion of the viscometer so that the liquid reservoir or the top of the capillary, whichever is
uppermost, is at least 20 mm below the upper bath level, and with provisions for visibility of the viscometer and the thermometer.
Firm supports for the viscometer shall be provided, or the viscometer may be an integral part of the bath. The efficiency of the
stirring and the balance between heat losses and heat input must be such that the temperature of the bath medium does not vary
by more than 60.03 °C [60.05 °F] over the length of the viscometer, or from viscometer to viscometer in the various bath
positions at 60 °C [140 °F].
NOTE 7—Distilled water is a suitable bath liquid for determinations at 60 °C [140 °F]. USP White Oil with a flash point above 215 °C [420 °F] has been
found suitable for determinations at 135 °C [275 °F]. The flash point is determined in accordance with Test Method D92.
6.4 Timer—A stopwatch or other timing device, graduated in divisions of 0.1 s or less and accurate to within 0.05 % when tested
over intervals of not less than 15 min. Timing devices for this test method must be standardized at least every twelve months.
6.4.1 Electrical Timing Devices may be used only on electrical circuits, the frequencies of which are controlled to an accuracy of
0.05 % or better.
6.4.1.1 Alternating currents, the frequencies of which are intermittently and not continuously controlled, as provided by some
public power systems, can cause large errors, particularly over short timing intervals, when used to actuate electrical timing
devices.
7. Preparation of Sample
7.1 To minimize loss of volatile constituents and to obtain reproducible results, proceed as follows:
7.1.1 Procedure for Liquid Asphalts, Distillation Residues, and Road Oil:
7.1.1.1 Allow sealed samples, as received, to reach room temperature.
7.1.1.2 Open the sample container and mix the sample thoroughly by stirring for 30 s, taking care to avoid the entrapment of air.
If the sample is too viscous for such stirring, place the sample in the tightly sealed container in a bath or oven maintained at 63
6 3 °C [145 6 5 °F] until it becomes sufficiently liquid for stirring.
D2170/D2170M − 24
7.1.1.3 Immediately charge the viscometer, or, if the test is to be made at a later time, pour approximately 20 mL into one or more
clean, dry containers having a capacity of approximately 30 mL and immediately seal with an airtight closure.
7.1.1.4 For materials with kinematic viscosities at 60 °C [140 °F] above 800 mm /s [cSt], heat the 20 mL sample in the sealed
container in an oven or bath maintained at 63 6 3 °C [145 6 5 °F] until it is sufficiently liquid for a convenient transfer into the
viscometer. Such heating should not exceed 30 min.
7.1.2 Procedure for Liquid Asphalts and Distillation Residues in the Range from 6 to 100 000 mm /s [cSt]:
7.1.2.1 Heat the sample with care to prevent local overheating until it has become sufficiently fluid to pour, occasionally stirring
the sample to aid heat transfer and to ensure uniformity.
7.1.2.2 Transfer a minimum of 20 mL into a suitable container and heat to 135 6 5.5 °C [275 6 10 °F], stirring occasionally to
prevent local overheating and taking care to avoid the entrapment of air.
8. Procedure
8.1 The specific details of operation vary somewhat for the various types of viscometers. See the detailed descriptions of
viscometers in Annex A2 for instructions for using the type of viscometer selected. In all cases, however, follow the general
procedure described in 8.2 – 8.8.
8.1.1 The specific details of operation for automated viscometers will vary from the manual procedure described in 8.4, 8.6, and
8.8. Refer to the operating instructions provided by the automated viscometer manufacturer.
8.2 Maintain the bath at the test temperature within 60.01 °C [60.02 °F]. Apply the necessary corrections, if any, to all
thermometer readings.
8.3 Select a clean, dry viscometer which will give an efflux time greater than 60 s and preheat to test temperature.
8.4 Charge the viscometer in the manner dictated by the design of the instrument, as prescribed in Annex A2.
8.5 Allow the charged viscometer to remain in the bath long enough to reach the test temperature, as prescribed in Annex A2.
8.6 Start the flow of asphalt in the viscometer as prescribed in Annex A2.
8.7 Measure to within 0.1 s the time required for the leading edge of the meniscus to pass from the first timing mark to the second.
If this efflux time is less than 60 s, select a viscometer of smaller capillary diameter and repeat the operation.
8.8 Upon completion of the test, clean the viscometer thoroughly by several rinsings with an appropriate solvent completely
miscible with the sample, followed by a completely volatile solvent. Dry the tube by passing a slow stream of filtered dried air
through the capillary for 2 min, or until the last trace of solvent is removed. Alternatively, the viscometer may be cleaned in a glass
cleaning oven at a temperature not to exceed 500 °C [932 °F], followed by rinses with distilled or deionized water, residue-free
acetone, and filtered dry air. Periodically, if deposits are observed, clean the instrument with a strong acid cleaning solution to
remove organic deposits, rinse thoroughly with distilled water and residue-free acetone, and dry with filtered dry air.
NOTE 8—The cleaning oven may burn off the glue that connects the viscometer tube to the holder.
8.8.1 Chromic acid cleaning solution may be prepared by adding, with the usual precautions, 800 mL of concentrated sulphuric
acid to a solution of 92 g of sodium dichromate in 458 mL of water. The use of similar commercially available sulphuric acid
cleaning solutions is acceptable. Nonchromium-containing, strongly oxidizing acid cleaning solutions may be substituted so as to
avoid the disposal problems of chromium-containing solutions.
8.8.2 Use of alkaline glass-cleaning solutions may result in a change of viscometer calibration, and is not recommended.
D2170/D2170M − 24
9. Calculation
9.1 Calculate the kinematic viscosity to three significant figures using the following equation:
Kinematic viscosity, mm /s @cSt# 5 Ct (1)
where:
2 2
C = calibration constant of the viscometer, mm /s [cSt/s], and
t = efflux time, s.
NOTE 9—Other ASTM publications on viscosity that may be used in conjunction with results determined in accordance with this test method are Test
Method D445, Practices D2493/D2493M and D341, and Specification D446.
10. Report
10.1 Always report the test temperature with the result, for example:
Kinematic viscosity at 60°C5 75.6 mm /s @cSt# (2)
11. Precision and Bias
11.1 Criteria for judging the acceptability of viscosity test results obtained by this method are given in Tables 1 and 2.
TABLE 1 Acceptability of Test Results for Kinematic Viscosity for
A
Liquid Asphalts at 60 °C
NOTE 1—The values given in Column 2 are the coefficients of variation
that have been found to be appropriate for the materials and conditions of
test described in Column 1. The values given in Column 3 are the limits
that should not be exceeded by the difference between the results of two
properly conducted tests.
Acceptable
Coefficient of
Range of
Material and Type Index Variation
Two Results
B
(% of mean)
B
(% of mean)
Single-operator precision:
Liquid asphalts at 60 °C [140 °F]:
below 3000 mm /s [cSt] 0.53 1.5
3000 to 6000 mm /s [cSt] 0.71 2.0
6000 mm /s [cSt] and above 3.2 8.9
Multilaboratory precision:
Liquid asphalts at 60 °C [140 °F]:
below 3000 mm /s [cSt] 1.06 3.0
2 C
3000 to 6000 mm /s [cSt] 3.11 9.0
2 C
above 6000 mm /s [cSt] 3.6 10.0
A
Supporting data and information for determining these estimates can be found in
Manning, R. E., “Comments on Vacuum Viscometers for Measuring the Viscosity
of
...