ASTM D4702-97(2003)
(Guide)Standard Guide for Inspecting Crosscut, Sweep-Arm, and Auger Mechanical Coal-Sampling Systems for Conformance with Current ASTM Standards
Standard Guide for Inspecting Crosscut, Sweep-Arm, and Auger Mechanical Coal-Sampling Systems for Conformance with Current ASTM Standards
SCOPE
1.1 This guide covers crosscut, sweep-arm, and auger sampling systems.
1.1.1 Crosscut and Sweep-Arm Samplers—A crosscut sampler collects an increment as the sampler traverses a freely falling stream of coal, such as coal falling in a chute or from the head pulley of a conveyor. A sweep-arm sampler collects an increment as the sampler traverses a bed of coal on a moving conveyor belt. Both crosscut and sweep-arm sampling are designated Condition B (Full-Stream Cut) as defined in Increment Collection Classification of Practice D 2234/D 2234M.
1.1.2 Auger Samplers—An auger sampler collects an increment of coal as the auger is inserted vertically into a stationary load of coal contained within a railcar, truck, or barge. Auger sampling is designated Condition D (Stationary Coal Sampling) as defined in Increment Collection Classification of Practice D 2234/D 2234M.
1.2 Spacing of increments pertains to the kind of interval between increments. Intervals can be defined in quantitative terms, such as units of time or mass, or in terms of position over the lot.
1.2.1 Spacing of Increments for Crosscut and Sweep-Arm Samplers—Crosscut- and sweep-arm-type mechanical sampling systems take increments based on time, either at fixed time intervals or at random times during a fixed time strata. Some crosscut samplers can take increments based on equal mass of coal sampled as determined by scales. The sections of this guide that pertain to crosscut and sweep-arm samplers describe procedures for only time-based sampling systems. This time-based inspection guideline will satisfy most criteria for mass-based or combination mass-based and time-based sampling systems. If there are items that are not covered, the inspector should refer to the manufacturer's literature.
1.2.2 Spacing of Increments for Auger Sampling—The spacing of increments collected by auger sampling systems is defined in terms of position over the lot.
1.3 It is essential that the inspector have the documentation listed in Section 2 of this guide when conducting an inspection.
1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
1.5 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 and health practices and determine the applicability of regulatory limitations prior to use. For a specific hazard statement, see Section 5.
General Information
Relations
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.
Designation: D 4702 – 97 (Reapproved 2003)
Standard Guide for
Inspecting Crosscut, Sweep-Arm, and Auger Mechanical
Coal-Sampling Systems for Conformance with Current
ASTM Standards
This standard is issued under the fixed designation D 4702; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope 1.3 It is essential that the inspector have the documentation
listed in Section 2 of this guide when conducting an inspection.
1.1 This guide covers crosscut, sweep-arm, and auger sam-
1.4 The values stated in SI units are to be regarded as the
pling systems.
standard. The values given in parentheses are for information
1.1.1 Crosscut and Sweep-Arm Samplers—A crosscut sam-
only.
pler collects an increment as the sampler traverses a freely
1.5 This standard does not purport to address all of the
falling stream of coal, such as coal falling in a chute or from
safety concerns, if any, associated with its use. It is the
theheadpulleyofaconveyor.Asweep-armsamplercollectsan
responsibility of the user of this standard to establish appro-
increment as the sampler traverses a bed of coal on a moving
priate safety and health practices and determine the applica-
conveyor belt. Both crosscut and sweep-arm sampling are
bility of regulatory limitations prior to use. For a specific
designated Condition B (Full-Stream Cut) as defined in Incre-
hazard statement, see Section 5.
ment Collection Classification of Practice D 2234/D 2234M.
1.1.2 Auger Samplers—An auger sampler collects an incre-
2. Referenced Documents
ment of coal as the auger is inserted vertically into a stationary
2.1 ASTM Standards:
load of coal contained within a railcar, truck, or barge. Auger
D 121 Terminology of Coal and Coke
sampling is designated Condition D (Stationary Coal Sam-
D 2013 Practice of Preparing Coal Samples for Analysis
pling) as defined in Increment Collection Classification of
D 2234/D 2234M Practice for Collection of a Gross Sample
Practice D 2234/D 2234M.
of Coal
1.2 Spacing of increments pertains to the kind of interval
D 4749 Test Method for Performing the Sieve Analysis of
between increments. Intervals can be defined in quantitative
Coal and Designating Coal Size
terms, such as units of time or mass, or in terms of position
D 4916 Practice for Mechanical Auger Sampling
over the lot.
1.2.1 Spacing of Increments for Crosscut and Sweep-Arm
3. Terminology
Samplers—Crosscut- and sweep-arm-type mechanical sam-
3.1 Definitions—Definitions applicable to this guide are
pling systems take increments based on time, either at fixed
listed in Terminology D 121, and Practices D 2234/D 2234M,
time intervals or at random times during a fixed time strata.
D 4916, and D 2013.
Some crosscut samplers can take increments based on equal
mass of coal sampled as determined by scales. The sections of
4. Significance and Use
this guide that pertain to crosscut and sweep-arm samplers
4.1 This guide addresses the quality assurance criteria for
describe procedures for only time-based sampling systems.
operation of a mechanical coal-sampling system in accordance
This time-based inspection guideline will satisfy most criteria
with Practices D 2234/D 2234M, D 2013, and D 4916. This
for mass-based or combination mass-based and time-based
guide serves as a reference for inspecting mechanical coal-
sampling systems. If there are items that are not covered, the
sampling systems for conformance with applicable ASTM
inspector should refer to the manufacturer’s literature.
standards. It describes step-by-step procedures for such inspec-
1.2.2 Spacing of Increments for Auger Sampling—The
tions, with specific ASTM references for each step.
spacing of increments collected by auger sampling systems is
defined in terms of position over the lot.
5. Hazards
5.1 Precautions—In addition to other precautions, person-
nel visiting facilities for observation of mechanical sampling
This guide is under the jurisdiction of ASTM Committee D05 on Coal and
Coke and is the direct responsibility of Subcommittee D05.23 on Sampling.
Current edition approved June 10, 2003. Published August 2003. Originally
approved in 1987. Last previous edition approved in 1997 as D 4702 – 97. Annual Book of ASTM Standards, Vol 05.06.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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.
D 4702 – 97 (2003)
system performance should, immediately upon arrival, report 7. General Observations of Coal Stream Variability as
to the facility management to inform them of their presence Related to Primary Increment Collection by Crosscut
and the purpose of their visit. The inspector should ask for and Sweep-Arm Samplers
drawings, specifications, and instructions on the applicable
7.1 The entire coal-handling system up to the crosscut or
safety practices and regulations to be followed on the site.
sweep-arm mechanical sampler should be examined to deter-
mine if any unloading, storage, or reclaiming procedures
6. Assessing the Organization and Planning of Sampling
produce a cyclical pattern which could cause the increment
Operations
collection to get in phase with the sequence of coal variability.
Variations in the physical characteristics, such as particle-size
6.1 It is recommended that inspection personnel meet with
distribution,surfacemoisture,extraneousmatter,andoversized
the appropriate personnel responsible for the mechanical sam-
material, can become cyclical and could even be in phase with
pling system, on all visits, to discuss the organization and
the time-based increment collection. When such cyclical varia-
planning of sampling operations. ASTM standards provide for
tions occur in the coal stream, the source of the variations
the use of various options. Examples and references are given
should be investigated to determine the practicability of
in 6.1.1 and 6.1.2 as follows:
eliminating the variations. If there is no practical way to
6.1.1 Crosscut and Sweep-Arm Samplers—The number of
eliminate the variations, then either the number of primary
primary increments for the gross sample collected by crosscut
increments or the primary cutter velocity, or both, shall be
or sweep-arm systems can be determined from the Sampling of
varied.
Coals Based on Size and Condition of Preparation or the
NOTE 1—The number of primary increments should be varied by
Sampling of Coals Based on Known Sampling Characteristics
adjusting the time interval between primary cuts so that the period of
of Practice D 2234/D 2234M.
cyclic variation is not evenly divisible by the number of primary cuts per
6.1.2 Auger Sampling—Considerations for the number of period or by using a method of random collection of primary increments.
auger increments per lot and per vehicle are discussed in the
8. General Observations of Auger Placement
ConsiderationforNumberofAugerIncrementssection(6.2)of
Practice D 4916. 8.1 At a minimum, the inspector should examine the fol-
lowing two aspects of the placement of the auger over the
6.2 Inspection personnel should refer to the sections of
surface of the coal being sampled: (1) human discretion in
Practice D 2234/D 2234M and Practice D 4916 referenced in
placement of the auger over the surface of the coal in the
6.2.1 and 6.2.2 of this guide when assessing the conformance
vehicle(s) and (2) the pattern of auger placement from vehicle
of the organization and planning of crosscut, sweep-arm, and
to vehicle for lots comprised of more than one vehicle load of
auger sampling operations as follows:
coal.
6.2.1 Planning of Crosscut or Sweep-Arm Sampling
8.1.1 Human Discretion—To the extent possible, human
Operations—When assessing the conformance of the organi-
discretion should be minimized with respect to auger place-
zation and planning of sampling operations for a specific
ment over the surface of the coal in the vehicle(s). The
crosscut or sweep-arm mechanical sampling system, the in-
inspector should examine the placement of the auger over the
spector should use Section 7, Organization and Planning of
surface of the coal in at least one vehicle to determine that
Sampling Operations, of Practice D 2234/D 2234M which
human discretion is minimized in positioning the auger.
covers the items that would be used in evaluating the sampling
8.1.2 Auger Placement Patterns—The inspector should re-
plan. Items covered are: Precautions, Selection of Appropriate
fer to the Considerations for Auger Placement Patterns and
Sampling Procedure, Number and Weight of Increments,
Increment Collections section (6.4) of Practice D 4916 in
Increment Collection Method to be Used, Distribution of
regard to considerations for auger placement patterns and
Increments, Dimensions of Sampling Device, Movement of
increment collections.
Sampling Device, Preservation of Moisture, Contamination,
Mechanical System Features, Personnel, Criteria of Satisfac-
9. Inspection of the Primary Sampler in Time-Based
tory Performance, and Relative Location of Sampling and
Crosscut or Sweep-Arm Sampling Systems
Weighing.
9.1 It is suggested that the inspector start at the primary
6.2.2 Planning of Auger Sampling Operations—When as-
crosscut or sweep-arm sampler and follow through the system
sessing the conformance of the organization and planning of
to the final online sample collection point. The inspection
sampling operations for a specific auger sampling system, the
should be made with and without coal running through the
inspector should use Section 6, Organization and Planning of
system.
Sampling Operations, of Practice D 4916, which covers the
9.2 The following items should be checked for the primary
following items: Precautions, Consideration of Top Size, Con-
sampler:
sideration for Number ofAuger Increments, Considerations for
9.2.1 Check the crosscut or sweep-arm cutter opening to
Auger Placement Patterns and Increment Collections, Preser-
determine that it complies with the Dimensions of Sampling
vation of Moisture, Contamination, Mechanical System Fea- Device of Practice D 2234/D 2234M.
tures, Personnel, Relative Location of Sampling andWeighing, 9.2.2 Sufficient inspection doors shall be available to ob-
and Reduction and Mechanical Division of the Auger Incre-
servethattheprimarycrosscutorsweep-armcuttercutsthefull
ments. stream of coal.
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.
D 4702 – 97 (2003)
9.2.3 Observe, or if necessary, measure, the movement of 11.3.1 The feeder shall be enclosed to minimize moisture
the primary crosscut or sweep-arm cutter to verify uniform change and designed to prevent spillage.
speed while in the coal stream.
11.3.2 A primary belt feeder or conveyor, or both, shall be
9.2.4 Determine the velocity of the crosscut or sweep-arm
provided with an effective wiper designed to discharge the
cutter by dividing the distance the cutter travels while in the
wipings into the next unit of the mechanical sampling system,
coal stream by the time required for traveling that distance.
thus avoiding loss of sample.
Make the velocity check for both directions if applicable. See
11.4 If the primary feeder discharges the primary increment
the Movement of Sampling Device section of Practice D 2234/
directly into a secondary sampler without intermediate crush-
D 2234M for recommendations. These recommendations are
ing, the inspector should check the following items:
not applicable to sweep-arm cutters.
11.4.1 A minimum of six secondary increments shall be
9.2.5 For crosscut or sweep-arm systems, it should be
collected from each uncrushed primary increment as specified
determined that the proper number of primary increments are
in Practice D 2234/D 2234M and 6.10.1.1 on Increments of
taken to satisfy the requirements of the Sampling of Coals
Practice D 4916. The six or more secondary increments should
Based on Size and Condition of Preparation or the Sampling of
be equally spaced throughout the entire flow of the primary
CoalsBasedonKnownSamplingCharacteristics(8.1)sections
increment.
of Practice D 2234/D 2234M. It should be determined that the
time interval between primary cuts is correct to ensure that the 11.4.2 Each secondary increment must conform to the
minimumnumberofincrementsarecollectedforthelotofcoal minimum increment weight specified in Table 2 of Practice
being sampled during the inspection based on maximum D 2234/D 2234M for nominal top size.
attainable feed rates.
11.4.3 Secondary cutter velocity must be uniform across the
9.2.6 The inspector shall determine that the crosscut sample
entire coal stream and conform to the recommendations of the
cutter is parked out of the stream of coal in the at rest position
Increment Collection Method to be Used and the Movement of
and that no coal is entering the cutter opening. There shall be
Sampling Device sections of Practice D 2234/D 2234M, and
no holes in the baffle plate, dust doors, or seals that may cause
the Speed of Sampling Device section (6.10.1.3) of Practice
leaking of the sample into the primary sample hopper.
D 4916.
9.2.7 For crosscut and sweep-arm systems, the minimum
NOTE 2—The use of a stopwatch may not provide sufficient accuracy
weight of the primary sample increment shall be as specified in
for short travel.
Table 2 of Practice D 2234/D 2234M.
11.4.4 Cutter opening shall conform to the recommenda-
10. Inspection of Augers
tionsoftheDimensionsofSamplingDevicesectionofPractice
10.1 The following items should be checked for the auger: D 2234/D 2234M, and the Opening of Sampling Device sec-
tion (6.10.1.2) of Practice D 4916.
10.1.1 Check the auger assembly to determine that it com-
plies with the Consideration of Top Size section (6.2) of
11.4.5 The secondary cutter is out of the coal stream when
Practice D 4916.
in the at rest position. See 9.2.6 of this guide for precautions
10.1.2 Check the auger to determine that it extracts a
against leakage.
vertical increment of coal extending from the surface to as
11.5 The sample crusher is fed from either the primary or
close as practicable to the bottom of the transport vehicle.
secondary sampler by a feeder. The requirements and criteria
10.1.3 For auger sampling systems, it should be determined
for the secondary feeder are the same as for the primary feeder
that the pro
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