ASTM D4040-10(2019)

Standard Test Method for Rheological Properties of Paste Printing and Vehicles by the Falling-Rod Viscometer

SIGNIFICANCE AND USE
5.1 Apparent viscosity at the relatively high shear rate of 2500 s−1 does not completely define the rheological properties of printing inks but is useful in the practical control of ink viscosity during production and the specification acceptance between supplier and purchaser.  
5.2 The slope of the power law plot is the preferred measure of non-Newtonianism. The yield value, which is obtained by extrapolation of high-shear measurements to a shear rate approaching zero, does not conform to the definition of the true yield stress (see 3.1.7). The yield value and other low shear parameters are also subject to a high degree of variability (see the precision table in Section 16).
SCOPE
1.1 This test method covers the procedure for determining the falling-rod viscosity and degree of non-Newtonian behavior of printing inks, vehicles, and similar liquids that are essentially nonvolatile and unreactive under ordinary room conditions.  
1.2 For printing inks, which are typically non-Newtonian, this test method is applicable in the apparent viscosity range from about 10 to 300 P at a shear rate of 2500 s−1. For Newtonian liquids, the applicable viscosity range is about 10 to 1000 P (1 P = 0.1 Pa·s).  
1.3 This test method uses a falling-rod viscometer in which shear conditions are altered by manually adding weight to the rod. A fully automatic instrument is described in Test Method D6606.  
1.4 This test method, as does Test Method D6606, bases calculations on the power law model of viscosity. ISO 12644 covers not only the power law but also the Casson and Bingham models.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this 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 to use. For specific hazard statements, see Section 8.  
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.

General Information

• Status: Published
• Publication Date: 31-Dec-2018
• ICS: 87.080 - Inks. Printing inks
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.56 - Printing Inks

Relations

• Replaces: ASTM D4040-10 - Standard Test Method for Rheological Properties of Paste Printing and Vehicles by the Falling-Rod Viscometer
• Effective Date: 01-Jan-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 D445-14 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 01-Jul-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 D445-12 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• Effective Date: 15-Apr-2012
• Refers: ASTM D6606-00(2010) - Standard Test Method for Viscosity and Yield of Vehicles and Varnishes by the Duke Viscometer
• Effective Date: 01-Dec-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 D6606-00(2005) - Standard Test Method for Viscosity and Yield of Vehicles and Varnishes by the Duke Viscometer
• Effective Date: 01-Sep-2005
• 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
• Refers: ASTM D445-04e2 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and the Calculation of Dynamic Viscosity)
• Effective Date: 01-Nov-2004
• Refers: ASTM D445-04 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and the Calculation of Dynamic Viscosity)
• Effective Date: 01-May-2004
• Refers: ASTM D445-03 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (the Calculation of Dynamic Viscosity)
• Effective Date: 10-Mar-2003
• Refers: ASTM D445-97 - Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (the Calculation of Dynamic Viscosity)
• Effective Date: 10-Jan-2001

Overview

ASTM D4040-10(2019) - "Standard Test Method for Rheological Properties of Paste Printing and Vehicles by the Falling-Rod Viscometer" - is an international standard developed by ASTM. It establishes a procedure to measure the viscosity and non-Newtonian behavior of printing inks, vehicles, and similar nonvolatile liquids using a falling-rod viscometer. This method provides critical quality control data, aids in product specification between suppliers and customers, and facilitates production consistency.

Key Topics

• Falling-Rod Viscometer: The main apparatus, where a weighted rod is allowed to fall through a liquid sample and the fall time is measured to determine viscosity.
• Apparent Viscosity: Measurement focuses on shear rate of 2500 s⁻¹, which is especially relevant for quality control of printing inks and vehicles.
• Non-Newtonianism: Inks usually deviate from Newtonian behavior. This method calculates the power law slope (N) from a log-log plot of shear stress vs. shear rate, providing a preferred metric of non-Newtonianism.
• Yield Value: The test uses extrapolation to estimate the pseudo yield value, a parameter useful for comparative characterization but not a true yield stress.
• Temperature Control: Viscosity can be temperature dependent; thus, strict temperature correction and monitoring are critical for repeatable results.
• Precision and Repeatability: The method provides guidance on repeatability and reproducibility, enabling quality lab practices and data comparison across production batches and labs.

Applications

This standard is widely applied in the printing ink and coatings industries, and is also relevant for other nonvolatile, unreactive liquids requiring controlled rheological properties. Key practical applications include:

• Quality Control in Production: Ensuring printing inks meet required viscosity specifications, preventing production issues such as poor print quality or equipment malfunction.
• Supplier-Buyer Specifications: Facilitating agreement on viscosity parameters between ink manufacturers and print operators or OEMs.
• Research and Development: Supporting the development of new inks and coating vehicles by providing reliable viscosity characterization across a relevant shear rate range.
• Inter-laboratory Comparisons: Enabling standardized viscosity data generation for benchmarking and compliance with rigorous product standards.

Typical materials tested: Offset lithographic inks, gravure inks, paste vehicles, and related nonvolatile liquid formulations.

Related Standards

Several other rheological test methods and standards are referenced in conjunction with ASTM D4040 to ensure comprehensive quality assessment:

• ASTM D445: Test Method for Kinematic Viscosity of Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity)
• ASTM D6606: Test Method for Viscosity and Yield of Vehicles and Varnishes by the Duke Viscometer (includes automatic instruments)
• ISO 12644: Graphic Technology-Determination of Rheological Properties of Paste Inks and Vehicles by the Falling Rod Viscometer (addresses additional models like Casson and Bingham)

These related documents provide complementary approaches for different materials, broader viscosity ranges, or automated testing options, ensuring ASTM D4040 users can adopt the right method for their specific needs.

---

By following ASTM D4040-10(2019), organizations benefit from reliable, practical control over the rheological properties of printing inks and vehicles, leading to enhanced product consistency, precise communication between parties, and strong compliance with international best practices in viscosity measurement. For those engaged in the manufacture, quality control, or use of printing inks and similar non-Newtonian liquids, this standard delivers essential value.

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: D4040 − 10 (Reapproved 2019)
Standard Test Method for
Rheological Properties of Paste Printing and Vehicles by the
Falling-Rod Viscometer
This standard is issued under the fixed designation D4040; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 2. Referenced Documents
1.1 This test method covers the procedure for determining
2.1 ASTM Standards:
the falling-rod viscosity and degree of non-Newtonian behav- D445Test Method for Kinematic Viscosity of Transparent
ior of printing inks, vehicles, and similar liquids that are
and Opaque Liquids (and Calculation of DynamicViscos-
essentially nonvolatile and unreactive under ordinary room ity)
conditions.
D6606Test Method for Viscosity and Yield of Vehicles and
Varnishes by the Duke Viscometer
1.2 For printing inks, which are typically non-Newtonian,
this test method is applicable in the apparent viscosity range
2.2 Other Standards:
−1
from about 10 to 300 P at a shear rate of 2500 s . For ISO 12644Graphic Technology—Determination of rheo-
Newtonianliquids,theapplicableviscosityrangeisabout10to
logical properties of paste inks and vehicles by the falling
1000 P (1 P=0.1 Pa·s). rod viscometer
1.3 This test method uses a falling-rod viscometer in which
3. Terminology
shear conditions are altered by manually adding weight to the
rod. A fully automatic instrument is described in Test Method
3.1 Definitions:
D6606.
3.1.1 apparent viscosity, V ,n—the viscosity of a non-
D
Newtonian fluid at a particular shear rate D.
1.4 This test method, as does Test Method D6606, bases
−1
3.1.1.1 Discussion—Ashearrateof2500s hasbeenfound
calculations on the power law model of viscosity. ISO 12644
useful for printing inks and is specified in this test method.
covers not only the power law but also the Casson and
Bingham models.
3.1.2 Newtonian, adj—refers to a liquid whose viscosity is
constant at all shear rates.
1.5 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
3.1.3 non-Newtonian, adj—refers to a liquid whose viscos-
standard.
ity varies with shear rate.
3.1.3.1 Discussion—Non-Newtonain liquids may be either
1.6 This standard does not purport to address all of the
shear-thinning (pseudoplastic) or shear-thickening (dilatant).
safety concerns, if any, associated with its use. It is the
Most printing inks are shear-thinning.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
3.1.4 shear rate, D, n—velocity gradient through the
−1
mine the applicability of regulatory limitations prior to use.
stressed liquid; the unit is 1/s or 1 s .
For specific hazard statements, see Section 8.
3.1.4.1 Discussion—Inthefalling-rodviscometer,shearrate
1.7 This international standard was developed in accor-
is inversely proportional to fall time F per unit distance L over
dance with internationally recognized principles on standard-
which a unit thickness x of the liquid is stressed: D= L/xF.
ization established in the Decision on Principles for the
3.1.5 shear stress, S, n—shearing force per unit area; the
Development of International Standards, Guides and Recom-
2 2
unit is 1 g/cm·s (1 dyne/cm ).
mendations issued by the World Trade Organization Technical
3.1.5.1 Discussion—In the falling-rod viscometer, shear
Barriers to Trade (TBT) Committee.
1 2
This test method is under the jurisdiction of ASTM Committee D01 on Paint For referenced ASTM standards, visit the ASTM website, www.astm.org, or
and Related Coatings, Materials, andApplicationsand is the direct responsibility of contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Subcommittee D01.56 on Printing Inks. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved Jan. 1, 2019. Published January 2019. Originally the ASTM website.
approved in 1981. Last previous edition approved in 2010 as D4040–10. DOI: Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
10.1520/D4040-10R19. 4th Floor, New York, NY 10036, http://www.ansi.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D4040 − 10 (2019)
−1
stressisproportionaltototalweightWperunitofshearingarea V = apparent viscosity at 2500 s ,P.
A times the gravitational constant g, in accordance with the W = total weight, g.
equation: S= Wg/A. W = added weight, g.
A
W = weight of rod, g.
R
3.1.6 viscosity, V, n—the ratio of shear stress to shear rate.
−1
W = weight required to obtain a shear rate of 2500 s ,
3.1.6.1 Discussion—The viscosity of a liquid is a measure
g.
of the internal friction of the liquid in motion. The cgs unit of
viscosity is 1 g/cm·s (1 dyne·s/cm ) and is called a poise. The
2 4. Summary of Test Method
SI unit is 1 N·s/cm and is equal to 10 P.
4.1 This test method is based on measurements of the time
3.1.7 yield stress, S,n—the minimum shear stress required
o
required for a weighted rod to fall through an aperture
to initiate motion in a non-Newtonian liquid.
containing the test specimen.
3.2 Definitions of Terms Specific to This Standard:
4.2 Fall times are corrected to a reference temperature of
3.2.1 Lehman yield value, n—calculated yield stress based
25°C (or other mutually agreed-upon temperature). The test
on the Lehman chart.
method specifies precise measurement of actual specimen
3.2.2 power law, n—a mathematical model that presumes
temperature in order to detect fluctuations due to cooling by
that the viscosity of a liquid varies with shear rate in accor-
metal, heat of friction during shearing, and body heat of the
dance with a power function as follows:
operator.
S
4.3 Each specific instrument must be calibrated in order to
k 5 (1)
N
D
establish the fall time that is equivalent to a shear rate of 2500
−1
s .
where:
k = a constant related to the viscosity of the liquid and 4.4 Fall times as a function of weight are extrapolated to
−1
N = a constant describing the rate at which shear stress 2500 s by means of the power law (logarithmic) relationship
varies with shear rate.
betweenshearstressandshearrate.Apparentviscosityat2500
−1
s and the degree of non-Newtonianism are determined by
3.2.2.1 Discussion—The value of N is precisely 1.0 for a
calculation or graphically.The calculation of several low shear
Newtonian fluid, less than 1.0 for a shear-thinning liquid, and
parameters is also covered.
greater than 1.0 for a shear-thickening liquid.
3.2.3 power law plot, n—a logarithmic plot of shear stress 5. Significance and Use
versusshearratebasedontheexpandedformofthepowerlaw
5.1 Apparent viscosity at the relatively high shear rate of
equation: −1
2500 s does not completely define the rheological properties
lnS 5 lnk1NlnD (2)
of printing inks but is useful in the practical control of ink
3.2.3.1 Discussion—For liquids conforming to the power
viscosity during production and the specification acceptance
law, the logarithmic plot of S versus D is linear over the shear
between supplier and purchaser.
rate range of interest. The slope of the line is the power law
5.2 Theslopeofthepowerlawplotisthepreferredmeasure
constant N.
of non-Newtonianism. The yield value, which is obtained by
3.2.4 pseudo yield value, n—calculated yield stress devel-
extrapolation of high-shear measurements to a shear rate
oped for use with the power law.
approachingzero,doesnotconformtothedefinitionofthetrue
yield stress (see 3.1.7). The yield value and other low shear
3.2.5 shortness, n—the property of a non-Newtonian fluid
parameters are also subject to a high degree of variability (see
that prevents it from being drawn into a filament.
the precision table in Section 16).
3.2.6 shortness factor (also called shortness ratio), n—ratio
of yield value to viscosity.
6. Apparatus
3.3 Symbols:
6.1 Fall-Time Runs:
3.3.1 (for Power-Law Calculations):
6.1.1 Falling-Rod Viscometer, equipped with a swinging
B = intercept of a straight line. 4
platform and automatic timing device accurate to at least 0.1
F = measured fall time, s.
s, preferably 0.01 s. A special lightweight rod is useful for
F = corrected fall time, s.
c
liquids in the 10-P range.
−1
F = fall time equivalent to a shear rate of 2500 s ,s.
6.1.2 Set of Tapped or Slotted Weights—Weights of 50 or
−1 −1 −1
K = apparent viscosity constant at 2500 s ,cm s .
100 to 500 g are usually provided with the instrument. Extra
N = slope of the power law plot, a measure of non-
500-g weights, approximately 4, totaling about 2000 g are
Newtonianism, cm /dyne·s.
requiredtohandlefluidsattheupperendofthepracticalrange.
−1
SF = shortness factor, s .
A 25-g weight is useful for liquids in the 10-P range.
S' = pseudo yield value, dyne/cm .
o
L 2
S = Lehman yield value, dyne/cm .
o
T = measured specimen temperature,°C.
Platform and timing device are standard on newer viscometer models. For
T = reference temperature, °C.
R equipping older models, see Bassemir, R, “Evaluation of the Laray Visocmeter,”
−1
V = apparent viscosity at 2.5 s ,P. American Ink Maker, Vol 39, No. 4, April 1961, pp. 24–26 and 60.
2.5
D4040 − 10 (2019)
6.1.3 A Thermostatically Controlled Cabinet or a Special 8.2.2 Weight loads in excess of 3000 g may cause bending
Collar, through which water is circulated from a constant- of the rod.
temperature bath (both are optional if room conditioning is not
8.2.3 To minimize heat buildup from body temperature
available). during a run, avoid contacting the viscometer block with bare
6.1.4 Thermistor, spanning the specified test temperature
hands. When instructions call for holding the block steady,
(usually 25°C), accurate to 0.01°C, and equipped with a probe wear a glove or place a small cloth in the palm of the hand.
having a response time of 3 to 6 s.
8.2.4 When making fall-time measurements, work quickly
6.1.5 Ring Stand and Clamp,orotherdeviceforholdingthe
and without interruption so that the entire run is completed
thermistor probe in a suitable position.
within 5 to 10 min.
6.1.6 SmallPlasticSpatula—Metalspatulasarenotsuitable.
NOTE 1—Many modern printing inks and vehicles contain some
6.1.7 Plastic Scraper, consisting of a piece of flexible
solvent,andvolatilelossduringaruncanseriouslybiastestresultsunless
plastic, approximately 30 by 70 mm, having a semicircle cut
rigorous control of exposure time is exercised. Volatile loss can be
out at one end; semicircle should fit the rod.
detected if successive drops of the rod with the same weight result in
increasingly longer fall times.
6.2 Instrument Calibration:
6.2.1 Balance, weighing to 0.1 g.
9. Preparation of Apparatus
6.2.2 Metric Rule or Scale, at least 100 mm in length.
9.1 Set the viscometer on a sturdy bench located in an area
6.2.3 Vernier Caliper, accurate to 0.01 mm, having a capac-
ity of at least 30 mm. free of direct drafts, direct sunlight, and other sources of heat.
Level the viscometer, using the adjustable feet.
6.3 Graphical Solutions:
6.3.1 Chart Paper, logarithmic 2×2 to 2×3 cycles. 9.2 Pass a hand over the upper and lower photocells to
6.3.2 Triangle,45°,withahypotenuselengthofatleast100 assure that the timer is activated and deactivated.
mm (approximately 8 in.).
9.3 Attach the clamp to the ring stand and place next to or
6.3.3 Protractor.
behind the viscometer. Drape the thermistor probe over the
clamp; reset the clamp so that the probe end falls close to the
7. Materials
viscometer block.
7.1 ASTM Standard Viscosity Oils, a minimum of two,
9.4 Clean the block and rod thoroughly with tissues wetted
preferablythree,spanningthepracticalrangeofthefalling-rod
with naphtha. Remove residual solvent with clean dry tissue.
viscometer (used for calibration purposes only).
Roll the clean dry rod over a flat surface to check for
7.2 Lithographic Varnishorsimilarvehiclehavingaviscos-
straightness.Ifrodisbent,discardandobtainanewrod/orifice
ity of about 200 P (for use in 12.3, if needed).
set.
7.3 Lint-and-Metal-Free Rags or Tissues.
9.5 Examine the markings at the ends of the rod. Select one
7.4 Naphthaorotherlow-boilingsolventinawashbottleor marking as an indication of the “proper” end to be always
closed metal container.
inserted into the aperture first.
8. Hazards
10. Calibration
8.1 SafetyPrecautions—Sincesolventsmaybehazardousto
10.1 Determineinstrumentconstantsinaccordancewiththe
theskinandeyes,inadditiontootherprecautions,wearrubber
procedure given in Annex A1.
gloves and safety glasses during cleanup to avoid solvent
10.2 Optional—Ifagraphicalmethodistobeusedfordirect
contact with skin and eyes. In case of contact, wash skin with
conversion of test results to viscosity, prepare Master Sliding
water; flush eyes for 15 min with water and call a physician.
Scale Calibration Graph as in Annex A2.
See supplier’s Safety Data Sheets for further information on
each solvent used.
10.3 Periodically check calibration as in A1.2.
8.2 Instrument Cautions:
11. Sample Preparation
8.2.1 Avoid any operation that will scratch the rod. Do not
use a metal spatula. Never drop the rod through an empty
11.1 Transport the sample to the test area and preserve in a
aperture.
closed container. Skin paper should be used for oxidative
drying inks.
11.1.1 Ink samples should be uniform dispersions. If pig-
Collars are available as accessories from the respective manufacturers of
falling-rod viscometers. ment settling is suspected, insert a spatula in the container and
The sole source of supply of the certified standard viscosity oil known to the
gently stir. Be careful not to introduce air bubbles.
committee at this time is Cannon Instrument Company, P.O. Box 16, State College,
11.1.2 Prior to the run, a portion of the sample may be
PA16801. If you are aware of alternative suppliers, please provide this information
transferred to a slab and gently spread out in order to remove
to ASTM International Headquarters. Your comments will receive careful consid-
erationatameetingoftheresponsibletechnicalcommittee, whichyoumayattend.
bubbles, skin, or other debris. (Warning—Do not work the
The Certified Viscosity Reference Standards table in Test Method D445 shows
sample vigorously;thispracticecausesasignificantincreasein
satisfactoryoilsincludingS-600(16Pat25°C),S-2000(56P),S-8000(230P),and
sampletemperature.Besuretoclosethecontainerimmediately
S-30000(810P).Viscosityatvarioustemperaturesisindicatedonthelabelofeach
container. after removing the desired portion.)
D4040 − 10 (2019)
12. Conditioning 13.6 Using experience or the information in Table 1 as a
guide,selectaweightloadthatwillproduceafalltimeasclose
12.1 The temperature of the room (cabinet or collar) should
to1or2sasis practical.
be set at 23 6 1°C (or 2°C below the reference temperature).
NOTE 3—For comparison of non-Newtonian liquids, runs must not be
NOTE 2—In accordance with Note 7, the allowable range for specimen
made at pre-specified rod weights. Rather, weights should be adjusted to
temperatureis 62°Cfromthereferencetemperature.However,duringthe
obtain pre-specified fall times, the first of which corresponds as closely to
course of testing, heat of shearing and body heat of the operator both
−1
a shear rate of 2500 s as is practical.
contribute to continuous temperature rises in test specimens, notwith-
13.7 Hold the block level and steady with one hand (see
standing room, cabinet, or collar conditions. To allow for inevitable
temperature rises, temperature controls are set at the lower end of the
8.2.3).Withtheotherhand,carefullyplacetheselectedweights
allowable range.
on top of the rod. If weights are slotted, evenly distribute the
12.2 Equilibration of test samples is not necessary. Speci-
slotsaroundthecircumferenceoftherod.Makecertainthatthe
mensizesaresmall(lessthan2mL);whenspreadoutonaslab rod is vertical. (If weights tend to make the viscometer
and applied to the viscometer, both hot and cold samples
unsteady, retain the hand on the block so that the rod falls
quickly reach the temperature of the metal. smoothly in 13.8.)
12.3 If the viscometer has been idle for more than an hour, 13.8 Setthetimer.Releasetheplatformandallowtherodto
it may be necessary to bring it into equilibrium with the fall naturally. If the fall time is within the desired range (for
conditioning temperature (23°C or other specified in 12.1). example, 1 to 2 s for the first weight, etc.), record the added
Make preparations for an exploratory run (13.2 – 13.5) using a weight W , fall time F, and specimen temperature T on
A
varnish if the test specimen contains volatiles. Read specimen worksheet.
temperature; if too low (a possibility considering that metal
13.9 Remove the weights from the rod. Pull the rod up
servesasaheatsink),adda1000-gweighttotherodandmake
slowly with the fingertips of one hand while holding the
a few drops (13.7 – 13.9 but without recording time) until the
viscometer block firmly with the other hand. Rest the rod on
specimen temperature reaches that of conditioning. Continue
the swinging platform. Using the plastic scraper, scrape the
the run or, if a varnish was used, clean up.
“collar” of specimen from the top to the bottom of the rod
where it enters the block. Gently rotate the rod in the well to
13. Procedure for Fall-Time Runs
redistribute the specimen.
13.1 Ifrequired,prepare,level,andconditiontheinstrument
13.10 Repeat the drop (13.7 – 13.9) with the same or
as described in 9.1 and 12.3.
adjusted weights until two fall times with a specific set of
13.2 Withtheproperendofthecleanroddown,holdtherod
weightsagreewithin2%(0.04sata2-sfalltime,0.2ata10-s
vertically over the clean aperture and gently lower until it rests
fall time, etc.).
on the swinging platform.
13.11 Make additional measurements (13.7 – 13.10) with
13.3 Transfer a uniform specimen to the tip of a clean succeedingly lighter sets of weights, each approximately 50%
plasticspatula.Thespecimensizeshouldbesufficienttofillthe
of the previous set, but do not exceed a fall time of 20 s.
well of the viscometer.
NOTE 4—Newtonian liquids may be run with only one or two sets of
weights. Non-Newtonian liquids require at least four or five.
13.4 Hold the rod with the fingertips and carefully raise
about20mm.Transferthespecimenfromthespatulatotherod 13.12 If the specimen is deplenished during the run, clean
as close as possible to the bottom of the well. Rotate the rod
upandstartoverfrom13.1,preferablyusinginkfreshfromthe
slowlytodistributethespecimenaroundthewell,ensuringthat
...