ASTM D7681-11(2016)e1

Standard Test Method for Measuring Gradation of Glass Spheres Using a Flowing Stream Digital Image Analyzer

SIGNIFICANCE AND USE
5.1 The gradation (size distribution) of glass beads has a significant influence on the retroreflective efficiency of a pavement marking system.  
5.2 This test method is for the characterization of the gradation (size distribution) of glass beads for the purpose of compliance testing against standard specification for glass beads in pavement marking applications.  
5.3 While there are potential industrial applications for this test method beyond the measurement of gradation (size distribution) of glass beads for pavement markings, those are beyond the scope of this standard.
SCOPE
1.1 This test method covers the determination of the gradation (size distribution) of glass spheres used in pavement marking systems using a Flowing Stream Digital Analyzer. Typical gradations for pavement marking systems are defined in ranges from Type 0 through 5 in AASHTO M247-08.  
1.2 This test method provides for the presentation of the size data in a variety of formats to the requirements of the agency pavement marking material specification. For most specifications the standard format is to present the size data as “Percent Retained” or “Percent Passing” relative to a series of standard US sieve sizes.  
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4 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.  
1.5 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: Historical
• Publication Date: 31-Mar-2016
• ICS: 93.080.20 - Road construction materials
• Technical Committee: D01 - Paint and Related Coatings, Materials, and Applications
• Drafting Committee: D01.44 - Traffic Coatings

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
´1
Designation: D7681 − 11 (Reapproved 2016)
Standard Test Method for
Measuring Gradation of Glass Spheres Using a Flowing
Stream Digital Image Analyzer
This standard is issued under the fixed designation D7681; 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—Subsection 6.1.3 was editorially corrected in October 2019.
1. Scope E177 Practice for Use of the Terms Precision and Bias in
ASTM Test Methods
1.1 This test method covers the determination of the grada-
E691 Practice for Conducting an Interlaboratory Study to
tion (size distribution) of glass spheres used in pavement
Determine the Precision of a Test Method
marking systems using a Flowing Stream Digital Analyzer.
Typical gradations for pavement marking systems are defined
2.2 AASHTO Standards:
in ranges from Type 0 through 5 in AASHTO M247-08.
AASHTO M247-08 Standard Glass Beads Used in Traffic
Markings
1.2 Thistestmethodprovidesforthepresentationofthesize
data in a variety of formats to the requirements of the agency
pavement marking material specification. For most specifica- 3. Terminology
tions the standard format is to present the size data as “Percent
3.1 Definitions:
Retained” or “Percent Passing” relative to a series of standard
3.1.1 flowing stream digital image analyzer, n—a computer
US sieve sizes.
controlled particle size analyzer employing a high resolution
1.3 The values stated in SI units are to be regarded as
digital imaging device and computer image processing soft-
standard. No other units of measurement are included in this
ware to do photo optical single particle counting and particle
standard.
size analysis.
1.4 This standard does not purport to address all of the
3.1.2 gradation of glass beads, n—the measurement of the
safety concerns, if any, associated with its use. It is the
size(diameter)ofglassbeadsandtheirsubsequentpresentation
responsibility of the user of this standard to establish appro-
in ranges between ASTM standard sieve sizes and/or micron
priate safety, health, and environmental practices and deter-
designation starting with the largest to the smallest; the ranges
mine the applicability of regulatory limitations prior to use.
are listed as “percent passing” and “percent retained.”
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the 4. Summary of Test Method
Development of International Standards, Guides and Recom-
4.1 The glass particles are run through a flowing stream
mendations issued by the World Trade Organization Technical
digital image analyzer, a measuring system for determining the
Barriers to Trade (TBT) Committee.
gradation (size distribution) of dry, free flowing and harmless
bulk products. The total recommended measuring range is
2. Referenced Documents
between 100 µm and 2.36 mm. The operating test method uses
2.1 ASTM Standards:
photo optical single particle counting technology for the image
B215 Practices for Sampling Metal Powders
processing. The measurement time depends on the quantity of
material to be measured, the width of the metering feeder and
This test method is under the jurisdiction of ASTM Committee D01 on Paint the mean grain size. The quantity of material to be measured
and Related Coatings, Materials, andApplications and is the direct responsibility of
depends on the grain size and the width of the metering feeder.
Subcommittee D01.44 on Traffic Coatings.
Typical measuring times are approximately 2 to 10 min.
Current edition approved April 1, 2016. Published April 2016. Originally
approved in 2011. Last previous edition approved in 2011 as D7681 – 11. DOI:
10.1520/D7681–11R16E01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Available from American Association of State Highway and Transportation
Standards volume information, refer to the standard’s Document Summary page on Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001,
the ASTM website. http://www.transportation.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
D7681 − 11 (2016)
5. Significance and Use 8.2 In order to obtain representative samples when sam-
pling from packaged containers, blenders or storage tanks,
5.1 The gradation (size distribution) of glass beads has a
methods outlined in Practices B215 shall be followed.
significant influence on the retroreflective efficiency of a
pavement marking system.
9. Preparation of Apparatus
5.2 This test method is for the characterization of the
9.1 Follow the manufacturer’s instructions for the particle
gradation (size distribution) of glass beads for the purpose of
analyzer being used.
compliance testing against standard specification for glass
beads in pavement marking applications.
10. Calibration and Standardization
5.3 While there are potential industrial applications for this
10.1 The particle analyzer, in most cases, will be calibrated
test method beyond the measurement of gradation (size distri-
by the manufacturer prior to shipping. Re-calibration might
bution) of glass beads for pavement markings, those are
become necessary occasionally, for example, after the trans-
beyond the scope of this standard.
portation of the instrument or if required by quality manage-
mentregulations.Inthiscase,followthecalibrationprocedures
6. Apparatus
as outlined in the manufacturer’s instruction manual.
6.1 Typical Instrument Operating Conditions (Fig. 1):
6.1.1 Environmental temperature — 10°C.40°C.
11. Conditioning
6.1.2 Air Humidity — 80 % maximum relative humidity at
11.1 Sample Preparation:
temperatures up to 30°C, linear decrease to 50 % maximum
11.1.1 Use a sample splitter, if necessary, to reduce the
relative humidity at a temperature of 40°C.
amount of sample to the appropriate size.
6.1.3 Height of installation and operation — maximum
11.1.2 Pour entire glass bead sample into the glass beaker or
3000 m above sea level.
suitable container.
6.1.4 Installation location — place the particle analyzer on
11.1.3 Assure glass beads are moisture free and free flow-
a firm, horizontal, vibration free surface.
ing.
6.1.5 Light conditions — avoid strong direct external light
NOTE 1—Check with instrument manufacturer for suggestions on how
on the particle measurement shaft or on the cameras.
tobestsetupanysoftwarethatcomeswiththeirinstrument.Settingupthe
6.1.6 This test method is designed for indoor or outdoor use
instrument software properly will speed up any glass sphere gradation
as prescribed by the manufacturer’s design and instructions.
measurements and allow for meaningful reports.
7. Hazards
12. Procedure
7.1 General Safety Information:
12.1 Load the sample into the feeder of the flowing stream
7.1.1 Operate the instrument in accordance with the manu-
digitalimageanalyzer.Theanalyzersoftwareallowstheuserto
facturer’s recommendations following all required safety pre-
carry out his measurements quickly and without error. All
cautions.
measuring and analysis parameters are determined initially and
set into the computer program. Different task files are created
8. Sampling, Test Specimens, and Test Units
for different specifications.
NOTE 2—When assigning sieve ranges to be used in a task file, the user
8.1 Obtain a minimum of approximately 50 6 5 g specimen
must use the ASTM mesh sieve choice, not the W. S. Tyler mesh. The
of the glass beads to be tested for gradation (size distribution).
quantity of the material to be measured has to be placed into the funnel of
For larger sizes of glass spheres, such as Type III and larger,
the metering feeder. The material handling mechanisms must not restrict
whose gradation is defined inAASHTO M247-08, 75 to 125 g
or segregate product flow in any way that allows for a non-representative
samples shall be used. flow of product through the measurement zone.
FIG. 1 Typical Apparatus
´1
D7681 − 11 (2016)
12.2 After the task file has been defined only a minimal 14.1.2 Repeatability Limit (r)—Two test results obtained
number of operative steps are required for carrying out a within one laboratory shall be judged not equivalent if they
measurement. They are: (a) filling a quantity of the material to differ by more than the “r” value for that material; “r”isthe
be measured into the funnel to the metering feeder, (b) calling interval representing the critical difference between two test
the measurement and choosing the task file, (c) confirming the results for the same material, obtained by the same operator
suggested comments or entering new comments, (d) starting using the same equipment on the same day in the same
the measurement, and (e) reading the result or printing a laboratory.
record. The measured result is available a few mo
...

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.
´1
Designation: D7681 − 11 (Reapproved 2016) D7681 − 11 (Reapproved 2016)
Standard Test Method for
Measuring Gradation of Glass Spheres Using a Flowing
Stream Digital Image Analyzer
This standard is issued under the fixed designation D7681; 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—Subsection 6.1.3 was editorially corrected in October 2019.
1. Scope
1.1 This test method covers the determination of the gradation (size distribution) of glass spheres used in pavement marking
systems using a Flowing Stream Digital Analyzer. Typical gradations for pavement marking systems are defined in ranges from
Type 0 through 5 in AASHTO M247-08.
1.2 This test method provides for the presentation of the size data in a variety of formats to the requirements of the agency
pavement marking material specification. For most specifications the standard format is to present the size data as “Percent
Retained” or “Percent Passing” relative to a series of standard US sieve sizes.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
1.5 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:
B215 Practices for Sampling Metal Powders
E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 AASHTO Standards:
AASHTO M247-08 Standard Glass Beads Used in Traffic Markings
3. Terminology
3.1 Definitions:
3.1.1 flowing stream digital image analyzer, n—a computer controlled particle size analyzer employing a high resolution digital
imaging device and computer image processing software to do photo optical single particle counting and particle size analysis.
3.1.2 gradation of glass beads, n—the measurement of the size (diameter) of glass beads and their subsequent presentation in
ranges between ASTM standard sieve sizes and/or micron designation starting with the largest to the smallest; the ranges are listed
as “percent passing” and “percent retained.”
4. Summary of Test Method
4.1 The glass particles are run through a flowing stream digital image analyzer, a measuring system for determining the
gradation (size distribution) of dry, free flowing and harmless bulk products. The total recommended measuring range is between
This test method is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and is the direct responsibility of
Subcommittee D01.44 on Traffic Coatings.
Current edition approved April 1, 2016. Published April 2016. Originally approved in 2011. Last previous edition approved in 2011 as D7681 – 11. DOI:
10.1520/D7681–11R16.10.1520/D7681–11R16E01.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American Association of State Highway and Transportation Officials (AASHTO), 444 N. Capitol St., NW, Suite 249, Washington, DC 20001,
http://www.transportation.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
´1
D7681 − 11 (2016)
100 μm and 2.36 mm. The operating test method uses photo optical single particle counting technology for the image processing.
The measurement time depends on the quantity of material to be measured, the width of the metering feeder and the mean grain
size. The quantity of material to be measured depends on the grain size and the width of the metering feeder. Typical measuring
times are approximately 2 to 10 min.
5. Significance and Use
5.1 The gradation (size distribution) of glass beads has a significant influence on the retroreflective efficiency of a pavement
marking system.
5.2 This test method is for the characterization of the gradation (size distribution) of glass beads for the purpose of compliance
testing against standard specification for glass beads in pavement marking applications.
5.3 While there are potential industrial applications for this test method beyond the measurement of gradation (size distribution)
of glass beads for pavement markings, those are beyond the scope of this standard.
6. Apparatus
6.1 Typical Instrument Operating Conditions (Fig. 1):
6.1.1 Environmental temperature — 10°C.40°C.
6.1.2 Air Humidity — 80 % maximum relative humidity at temperatures up to 30°C, linear decrease to 50 % maximum relative
humidity at a temperature of 40°C.
6.1.3 Height of installation and operation — maximum 3003000 m above sea level.
6.1.4 Installation location — place the particle analyzer on a firm, horizontal, vibration free surface.
6.1.5 Light conditions — avoid strong direct external light on the particle measurement shaft or on the cameras.
6.1.6 This test method is designed for indoor or outdoor use as prescribed by the manufacturer’s design and instructions.
7. Hazards
7.1 General Safety Information:
7.1.1 Operate the instrument in accordance with the manufacturer’s recommendations following all required safety precautions.
8. Sampling, Test Specimens, and Test Units
8.1 Obtain a minimum of approximately 50 6 5 g specimen of the glass beads to be tested for gradation (size distribution). For
larger sizes of glass spheres, such as Type III and larger, whose gradation is defined in AASHTO M247-08, 75 to 125 g samples
shall be used.
8.2 In order to obtain representative samples when sampling from packaged containers, blenders or storage tanks, methods
outlined in Practices B215 shall be followed.
9. Preparation of Apparatus
9.1 Follow the manufacturer’s instructions for the particle analyzer being used.
10. Calibration and Standardization
10.1 The particle analyzer, in most cases, will be calibrated by the manufacturer prior to shipping. Re-calibration might become
necessary occasionally, for example, after the transportation of the instrument or if required by quality management regulations.
In this case, follow the calibration procedures as outlined in the manufacturer’s instruction manual.
FIG. 1 Typical Apparatus
´1
D7681 − 11 (2016)
11. Conditioning
11.1 Sample Preparation:
11.1.1 Use a sample splitter, if necessary, to reduce the amount of sample to the appropriate size.
11.1.2 Pour entire glass bead sample into the glass beaker or suitable container.
11.1.3 Assure glass beads are moisture free and free flowing.
NOTE 1—Check with instrument manufacturer for suggestions on how to best set up any software that comes with their instrument. Setting up the
instrument software properly will speed up any glass sphere gradation measurements and allow for meaningful reports.
12. Procedure
12.1 Load the sample into the feeder of the flowing stream digital image analyzer. The analyzer software allows the user to carry
out his measurements quickly and without error. All measuring and analysis parameters are determined initially and set into the
computer program. Different task files are created for different specifications.
NOTE 2—When assigning sieve ranges to be used in a task file, the user must use the ASTM mesh sieve choice, not the W. S. Tyler mesh. The quantity
of the material to be measured has to be placed into the funnel of the metering feeder. The material handling mechanisms must not restrict or segregate
product flow in any way that allows for a non-representative flow of product through the measurement zone.
12.2 After the task file has been defined only a minimal number of operative steps are required for carrying out a measurement.
They are: (a) filling a quantity of the material to be measured into the funnel to the metering feeder, (b) calling the measurement
and choosing the task file, (c) confirming the suggested comments or entering new comments, (d) starting the measurement, and
(e) reading the result or printing a record. The measured result is available a few moments after the measurement is completed and
can be displayed in many forms, and be printed and saved with the help of the PC.
13. Report
13.1 Report the percentage of particles in each size cla
...