ASTM D5192-99(2004)

Standard Practice for Collection of Coal Samples from Core

SCOPE
1.1 This practice describes procedures for collecting and handling a coal sample from a core recovered from a borehole.
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.
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.

General Information

• Status: Historical
• Publication Date: 31-Mar-2004
• Technical Committee: D05 - Coal and Coke

Relations

• Replaces: ASTM D5192-99 - Standard Practice for Collection of Coal Samples from Core
• Effective Date: 01-Apr-2004
• Replaced By: ASTM D5192-99(2004)e1 - Standard Practice for Collection of Coal Samples from Core
• Effective Date: 01-Apr-2004
• Referred By: ASTM D3176-15 - Standard Practice for Ultimate Analysis of Coal and Coke
• Effective Date: 01-Apr-2004
• Referred By: ASTM D6796-21e1 - Standard Practice for Production of Coal, Coke and Coal Combustion Samples for Interlaboratory Studies
• Effective Date: 01-Apr-2004
• Referred By: ASTM D3172-13(2021)e1 - Standard Practice for Proximate Analysis of Coal and Coke
• Effective Date: 01-Apr-2004
• Referred By: ASTM D7569/D7569M-10(2015)e1 - Standard Practice for Determination of Gas Content of Coal—Direct Desorption Method
• Effective Date: 01-Apr-2004
• Referred By: ASTM D121-15 - Standard Terminology of Coal and Coke
• Effective Date: 01-Apr-2004
• Referred By: ASTM D5671-20 - Standard Practice for Polishing and Etching Coal Samples for Microscopical Analysis by Reflected Light
• Effective Date: 01-Apr-2004
• Referred By: ASTM D388-23 - Standard Classification of Coals by Rank
• Effective Date: 01-Apr-2004
• Referred By: ASTM D4596-22 - Standard Practice for Collection of Channel Samples of Coal in a Mine
• Effective Date: 01-Apr-2004

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D5192–99(Reapproved 2004)
Standard Practice for
Collection of Coal Samples from Core
This standard is issued under the fixed designation D 5192; 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 and which erode or abrade the sidewall of the borehole by the
action of the drilling. These zones can affect the accuracy of
1.1 This practice describes procedures for collecting and
certain geophysical logs (especially density). Corrections to
handling a coal sample from a core recovered from a borehole.
other geophysical logs can be made if a caliper log is available.
1.2 The values stated in SI units are to be regarded as the
The most common causes of caves or washouts include soft or
standard. The values given in parentheses are for information
fractured lithologies, the presence of water-producing zones,
only.
and the downhole pressure of the drilling medium (fluid or air)
1.3 This standard does not purport to address all of the
thatoftencausesdifferentialerosionofvariousstratawithinthe
safety concerns, if any, associated with its use. It is the
borehole.
responsibility of the user of this standard to establish appro-
3.1.3 concretion, n—in a geological sense, a mass of min-
priate safety and health practices and determine the applica-
eral matter found in rock of a composition different from its
bility of regulatory limitations prior to use.
own and produced by deposition from aqueous solution in the
2. Referenced Documents
rock.
3.1.4 core,n—indrilling,acylindricalsectionofrock(coal)
2.1 ASTM Standards:
that is usually 5 to 10 cm in diameter, taken as part of the
D 121 Terminology of Coal and Coke
interval penetrated by a core bit and brought to the surface for
D 388 Classification of Coals by Rank
geologic examination, representative sampling, and laboratory
D 1412 Test Method for Equilibrium Moisture of Coal at 96
analyses.
to 97 Percent Relative Humidity and 30°C
3.1.5 core barrels, n—two nested tubes above the bit of a
D 2013 Practice of Preparing Coal Samples for Analysis
coredrill,theouterrotatingwiththebit,theinnerreceivingand
D 2796 Terminology Relating to Megascopic Description
preserving a continuous section or core of the material pen-
of Coal and Coal Seams and Microscopical Description
etrated.Thefollowingtwotypesofinnerbarrelsarecommonly
and Analysis of Coal
used.
D 4371 Test Method for Determining the Washability Char-
3.1.5.1 split-tubebarrel,n—atypeofinnerbarrelconsisting
acteristics of Coal
oftwolongitudinalhalvesofpipeboundtogetherbyreinforced
D 4596 Practice for Collection of Channel Samples of Coal
tape at intervals along the barrel length that allows easy access
in a Mine
to a relatively intact core (but cutting the tape). (This is the
3. Terminology
preferred barrel type for coal exploration, when available.)
3.1.5.2 solid-tube barrel, n—a type of inner barrel consist-
3.1 Definitions—For additional definitions of terms, refer to
ing of a single solid-walled length of pipe in which removal of
Terminology D 121.
the core is accomplished by mechanical or hydraulic pressure
3.1.1 borehole, n—the circular hole through soil and rock
at one end of the pipe thus extruding the core onto a core tray.
strata made by boring.
(Thecoreislikelytobelessintactthanwhenasplit-tubebarrel
3.1.2 caves or washouts, n—zones of increased hole diam-
is used.)
eter caused by rock fragments that fall from the walls of a
3.1.6 core sample, n—that part of a core of rock or coal
borehole and can block the hole or contaminate the cuttings
obtained so as to accurately represent a thickness of a unit
penetrating by drilling.
This practice is under the jurisdiction of ASTM Committee D05 on Coal and
3.1.7 geophysical log, n—a graphic record of the measured
Coke and is the direct responsibility of Subcommittee D05.18 on Classification of
or computed physical characteristics of the rock section en-
Coals.
countered in a borehole, plotted as a continuous function of
Current edition approved April 1, 2004. Published May 2004. Originally
approved in 1991. Last previous edition approved in 1999 as D 5192 – 99. depth. Measurements are made by a sonde, which contains the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
detectors, as it is withdrawn from the borehole by a wire line.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Several measurements are usually made simultaneously, and
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
Withdrawn.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D5192–99 (2004)
the resulting curves are displayed side by side on the common minimized. From this core, coal and roof and floor material of
depth scale. A common suite of logs used in coal exploration interest are collected for analysis and testing.
include caliper, density (gamma-gamma), natural gamma, and
resistivity. 5. Significance and Use
3.1.7.1 caliper log, n—a continuous mechanical measure-
5.1 A properly collected sample that includes the total coal
ment of the diameter and thus the rugosity of the borehole.The
bed interval provides a sample that is a representative cross
tool identifies zones where swelling or cavings (washouts)
section of the coal bed at the point of sampling. Core samples
have occurred during drilling. The tool’s value is in allowing
are taken for subsequent testing needed for evaluation of coal
qualitative or quantitative corrections to be made to other
quality and characterization for commercial evaluations, for
geophysical logs which are affected by borehole size (espe-
planning of mining operations to maintain coal quality, for the
cially density).
determination of coal rank in accordance with Classification
3.1.7.2 density log (gamma-gamma log), n—measures elec-
D 388, and for geologic coal resource studies.
tron density within lithologic units which is related to their
NOTE 1—Because of the potential for lateral variability, a sample may
bulk density. The wireline tool records the intensity of gamma
not represent the quality of the coal bed at another sample point. The
radiation (in counts per second) from a nuclear source within
reliability of the data generated from core samples is dependent on the
the tool after it has been attenuated and backscattered by
number and spacing of the sample points and the variability of the coal
lithologies within the borehole. Due to the distinctly low
characteristics in a given area.
density of coals, the density log is essential in coal exploration
6. Apparatus
for identifying coal seams and coal-seam partings. The bias/
6.1 Steel Measuring Tape, not less than 10 m (30 ft) long.
resolution of density logs can be affected by source-detector
spacing(closerspacingincreasesresolution),boreholesizeand 6.2 Rock Hammer, Chisel, or Pick, with file for sharpening.
6.3 Water Source, to provide fresh, clean water for rinsing
irregularities (see caves or washouts), and the presence of
casing and logging speed. drilling mud from cut surface of the core.
6.4 Waterproof Marking Pencils that are visible on coal,
3.1.7.3 natural gamma-ray log, n—a record of the natural
such as a yellow lumber crayon.
radioactivity of the lithologies encountered in the borehole
6.5 Polyethylene Bags, Tubing, or Sheets, 0.1 mm (4 mil) or
environment. During recording of geophysical logs, the
thicker.
amount of natural radiation is recorded and presented in either
6.6 Core Tray, constructed of wood, plastic, or metal, onto
counts per second (CPS) or American Petroleum Institute
which to extrude the core from the core barrel.
(API) units. Unlike many other log types, a representative
6.7 Boxes for Core Storage, constructed of wood, plastic, or
natural gamma log can be obtained where borehole or fluid
coated cardboard or if the core is to remain stratigraphically
conditions, or both, are not optimal or where casing is present.
oriented, use containers such as poly(vinyl chloride) (PVC)
The natural gamma log is most often used in the coal
pipe.
environment for identifying classic lithologies and differenti-
6.8 Tags and Waterproof Marking Pens, for sample identi-
ating coal seams and coal-seam partings.
fication and for marking depths, orientation, and so forth, on
3.1.7.4 resistivity log, n—a measure of the voltage differen-
the plastic sheeting.
tial of strata along the walls of a borehole when electrical
6.9 NotebookandPencil,orothermeansforrecordkeeping.
current is passed through the strata. The resistivity log requires
6.10 Waterproof Container, to hold sample tag.
a fluid-filled hole to constantly provide a conductive medium
6.11 Geophysical Logging Unit (optional), consisting of
between electrodes on the tool. The spacing between the
recording equipment and sondes for high-resolution density
electrodes determines the precision of the bed boundary
and caliper logs and possibly gamma and resistivity logs.
relationships in much the same manner as with the density log.
The resistivity log is useful primarily in conjunction with other
7. Planning for Sampling
log types. The logs are affected by casing, logging speed,
electrode spacing, formation porosity, and resistivity changes 7.1 Obtain information such as geologic, topographic, and
in the borehole fluid.
land ownership for locating suitable sites for drilling. Choose
3.1.8 floor, n—the rock material immediately underlying a sites that will best satisfy the purpose of sampling.
coal bed. 7.2 A core approximately 47 mm (1.87 in.) in diameter
yields a sufficient sample for most purposes. Minimum sample
3.1.9 roof, n—the rock material immediately overlying a
coal bed. mass requirements for analytical tests, such as washability
testing, may dictate a sample mass that can only be obtained
3.1.10 sonde, n—an elongate cylindrical tool assembly used
from larger diameter cores or multiple separate cores.
in a borehole to acquire a geophysical log.
NOTE 2—The diameter and length of the core (or number of separate
4. Summary of Practice
cores) required to obtain a desired mass of sample may be estimated from
the density of coal, approximately 1.3 to 1.35 g/cm . The selected
4.1 Atselectedsitesinadepositofcoal,aboreholeisdrilled
diameter of the core can have an effect on the representativeness of
and the core containing the coal and surrounding strata of rock
subsamples obtained from the core sample for various types of testing.As
is recovered.
an example in washability testing, the diameter of the core should be at
4.2 The coal core is cleaned of drilling fluid, if necessary,
least three times the largest dimension of the top size of any subsamples
properly described, and packaged so that loss of moisture is to be obtained from the core sample. For information on determining the
D5192–99 (2004)
washability characteristics of coal, seeTest Method D 4371 and the report
seam is not possible on every core under even the best of field
by Wizzard.
conditions. However, useful information such as apparent rank
A larger diameter core can also be necessary to obtain a more
can many times be obtained from cores where less than 100 %
representative sample if the quality of the coal varies greatly from layer to
of the seam has been recovered. When portions of the interval
layer in the seam.
have been lost, the following information should be recorded:
7.3 Increment Sampling—Where differences of coal quality
(1) the percent recovery and (2) the estimated location and
parameters exist among different layers or benches in the same
thickness of the lost intervals. Use of data from cores that
coal seam or where the seam is thick, it is best to sample and
represent less than 100 % of the total seam thickness shall be
analyze the seam in vertical increments.
identified as such and used with caution.
7.3.1 Compositing —Data obtained from the separate
8.2 Determining Recovery From Comparison of Geophysi-
analyses of the vertical core increments can be composited by
cal Logs and Core —The most reliable measurement of coal
calculation,preferablybysamplemassifsufficientinformation
seam thickness can be obtained from deflections on the
such as core length and density has been measured for each
high-resolution density log and the caliper log. If the roof and
increment.Alternatively,acompositesampleoftheentireseam
floor lithologies are other than sandstone, the resistivity and
can be produced by combining representative splits of the
natural gamma can also be used, especially if caves or
increments by increment thickness for the determination of
washouts have caused material to be lost during coring.
whole core characteristics. The use of an ash/density relation-
Generally, the midpoint (the point at one half the deflection
ship for the specific geographic area and seam being studied
between the lithologic-density lines) on the log trace is used to
can be helpful in validating direct density measurements.
determine bed boundaries. However, for certain geophysical
Extreme care and cross-checking should be exercised when
toolsitmaybenecessarytouseothercriteria,suchasone-third
combiningasamplecompositeforanalysisorwhencalculating
deflection, initial deflection, and so forth. Geophysical tool
a composite analysis from the analysis of increments. Some
manufacturers or service companies have specific instructions
coal quality parameters are not additive in a linear fashion and
forthecalibrationandinterpretationoftheirlogsandshouldbe
cannot be accurately determined by calculated compositing.
consulted by the user.
Fusion temperatures of ash and Hardgrove grindability and
8.3 Regardless of the method used to determine thickness,
Gieseler fluidity indices are examples of physical properties
check the estimated thickness from the geophysical log(s)
that are nonadditive and best determined on whole samples.
against measured coal-core sections for final determination.
7.4 Sampling Plans for Different Purposes:
This is particularly critical in cases of gradational contacts or
7.4.1 Variations in the purpose of sampling and in condi-
thin, dense partings for which thicknesses are commonly
tions encountered in the field may preclude the establishment
overexaggerated by the response of the geophysical tool.
of rigid procedures covering every sampling situation. There-
Generally, thicknesses can be determined from geophysical
fore, formulate a plan taking into account the conditions of
tools within 630 mm (0.1 ft
...