1、Designation: D6883 04 (Reapproved 2012)D6883 17Standard Practice forManual Sampling of Stationary Coal from Railroad Cars,Barges, Trucks, or Stockpiles1This standard is issued under the fixed designation D6883; the number immediately following the designation indicates the year oforiginal adoption o
2、r, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers procedures for obtaining a manual gross sample from benea
3、th the surface of coal in railroad cars,barges, trucks, or stockpiles. These procedures are to be used to provide gross samples for estimating the quality of the coal. Thegross samples are to be crushed, divided, and further prepared for analysis in accordance with Practice D2013.1.2 This practice p
4、rovides instruction for sampling beneath the exposed surface coal to a depth of approximately 61 cm (24 in.).Collect samples at this depth to get below the surface of the material, since drying and oxidation may have occurred at, or nearthe surface. Changes in moisture, in particle size, and in othe
5、r properties continue to occur deeper in the coal and, although notas drastic as near the surface, will cause the method to be biased. The user should review the conditions of the coal (weatherconditions, prior transport, settling time, and so forth, see 8.1) so that the interested parties can agree
6、 that potential biases are notoverly great or that some adjustment in specifications is warranted. Sample increments collected from the surface layer(s) of coalin railroad cars, barges, or stockpiles are classified condition “D” (see Practice D2234/D2234M, Increment CollectionClassification). It is
7、a good practice to require that “details of sampling procedure shall be agreed upon in advance by all partiesconcerned” whenever collection of sample increments falls under condition “D.” This practice offers a sampling procedure thatparties may use to meet requirements of Practice D2234/D2234M for
8、condition “D.” The practice does not produce samples thatsatisfy precision requirements of Practice D2234/D2234M general-purpose sampling, or Practice D2234/D2234M special-purposesampling.1.3 The user is cautioned that samples of this type do not satisfy the minimum requirements for probability samp
9、ling and assuch cannot be used to draw statistical inferences such as precision, standard error, or bias.1.4 This sampling method is intended for use only when sampling by more reliable methods that provide a probability sampleis not possible.1.5 The quantities stated in either acceptable SI units o
10、r in inch-pound units are regarded separately as standard. The quantitiesstated in each system may not be exact equivalents; therefore, each system must be used independently of the other, withoutcombining quantities in any way.1.6 This standard does not purport to address all of the safety concerns
11、, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and healthsafety, health, environmental practices and determine theapplicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance
12、with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standard
13、s:2D121 Terminology of Coal and CokeD2013 Practice for Preparing Coal Samples for AnalysisD2234/D2234M Practice for Collection of a Gross Sample of CoalD4749 Test Method for Performing the Sieve Analysis of Coal and Designating Coal Size1 This practice is under the jurisdiction of ASTM Committee D05
14、 on Coal and Coke and is the direct responsibility of Subcommittee D05.23 on Sampling.Current edition approved Nov. 1, 2012Oct. 15, 2017. Published December 2012October 2017. OrginallyOriginally approved in 2003. Last previous edition approved in20042012 as D688304.D688304(2012). DOI: 10.1520/D6883-
15、04R12.10.1520/D6883-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard
16、and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases onl
17、y the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D4916 Practice for Mechanical Auger Sampling (Withdrawn 2008)3E105 Practice for Probab
18、ility Sampling of MaterialsE177 Practice for Use of the Terms Precision and Bias in ASTM Test MethodsE456 Terminology Relating to Quality and Statistics3. Terminology3.1 Definitions:3.1.1 consignment, na discrete amount of coal, such as a shipment, a carload, a unit train, or a days production. Acon
19、signment may include more than one lot of coal and may correspond to a specific period of time such as sampling period orbilling period.3.1.2 particle segregation, nthe segregation of sized particles to specific areas as a result of the particles rolling, falling, orsliding down the sides of a pile
20、or a result of the peculiarities of a coal handling system used to build the pile. Particle segregationis a process of separation, not exclusively by size, but by size, shape, and density.3.1.3 stockpile, nmaterial stored or reserved in a stacked pile or heap.4. Summary of Practice4.1 Use of this pr
21、actice is limited to manual collection of sample increments from beneath the surface layer(s) of stationary coalfrom railroad cars, barges, trucks, or stockpiles for the purpose of acquiring a gross sample.5. Significance and Use5.1 These guidelines provide procedures for manually collecting gross s
22、amples from beneath the exposed surface of coal inrailroad cars, barges, trucks, or stockpiles taking into account the wide variety of conditions that may be encountered. The samplesare further processed for the laboratory to provide estimations of the coal quality. The use of this practice is condi
23、tional uponagreement among all interested parties concerning all relevant details of sample collection before sampling begins. These include,but are not limited to: lot size; number and mass of increments; the size, shape, and manipulation of the increment collectiondevices; location of increment co
24、llection site or sites; circumstances under which increments are not to be collected or suspended;and safety precautions. It is preferable that such agreements be in writing. The user is cautioned that samples so obtained do notrepresent material below the point of penetration.6. Hazards6.1 WarningS
25、tockpile sampling involves exposure to hazardous operations, conditions, and equipment. Awareness topersonnel safety cannot be overemphasized. Personnel may require approved federal and/or state safety training before taking partin field sampling. Site-specific safety regulations must be observed. T
26、his includes personnel wearing all specified personalprotection equipment. The general safety precautions necessary when working around moving equipment must be observed.Sampling technicians must never work in coal that is piled or in railroad cars over hoppers and/or feeders or where there is thepo
27、ssibility of the coal being eroded from beneath them. Sampling should never be performed near a face of a stockpile where theface extends upward at an angle greater than the angle of repose of the coal.7. Procedure7.1 ObservationsBefore sampling a lot of coal using this method, perform a visual insp
28、ection for particle distribution andpossible particle segregation within the stockpile. Notes should be made on the sampling log to reflect these observations. Thesenotes could be useful in understanding differences of analytical test results or in identifying changes in stockpiling characteristics.
29、The approximate top size of the coal on the surface layer should be estimated in this step.7.2 Lot SizeAll interested parties should agree to the size of the lot to be represented by one gross sample before samplingbegins.7.3 Weight of IncrementsIncrement weights are to be equal to, or in excess of,
30、 those contained in Table 2 of PracticeD2234/D2234M. All increments should be of approximately equal mass.7.4 Number of IncrementsMeaningful levels of precision cannot be obtained with the methods described herein. Determinethe number of increments to be collected for one gross sample using Eq 1. Fe
31、wer increments are permissible if agreed upon inadvance. Since meaningful levels of precision cannot be obtained for these samples, any multiplier can be considered valid in placeof the number 35 in Eq 1 if agreed upon by the parties concerned.N 535total lot size Mg or tons!908 Mg or 1000 tons (1)3
32、The last approved version of this historical standard is referenced on www.astm.org.D6883 172where:N = number of increments.7.5 Increment CollectionCollect increments from a depth of approximately 61 cm (24 in.), on top of conveyances, around thebase of the stockpile, and up the slopes of the pile.
33、The angles of the sides of the holes should be less than the angle of repose.Place the coal that is removed from the holes away from the sampling area. Remove the increment from the bottom of the holeand place it into the container. Avoid any spillage.7.5.1 The pattern of increment placement can be
34、dependent upon the size and number of conveyances or height and shape ofthe stockpile. Space the increments over the surface of the coal so that each increment will represent equally sized areas. This willrequire different spacing of increments as the size and number of conveyances or the profile of
35、 the pile changes. The Appendixcontains a discussion of pattern selection for collection of increments from coal in conveyances.7.5.2 As increments are collected, protect them from contamination and moisture change. Place the increments in plastic-linedcanvas bags, metal drums with plastic liners, p
36、lastic buckets with airtight lids, or other moisture impervious containers. Eachsample must be clearly identified. Place a moisture-proof identification tag inside the sample container and attach another securelyon the outside of the sample container. Sample identification shall include the sampling
37、 technicians initials, the date, the location,weather conditions, the number of increments, and the sampling method used. This information will become part of the analyticalreport. Other notes or pertinent information can be recorded in the sampling log (see Section 8). This information may or may n
38、otbe in the report, but it shall be retained as a part of the laboratory record.7.6 Collection DevicesThe estimated top size of the coal ascertained in 7.1 should be used to determine the opening size ofthe increment collection device. It should be a minimum of two and one half 3 times the top size
39、of the coal. Types and dimensionsof sampling implements should be agreed upon by all interested parties before commencement of sampling.Acommon flat, squareshovel with the two sides and the back built up with metal plates which are at least 10 cm (4 in.) high is a device that is commonlyused to obta
40、in manual samples See Fig. 1.7.6.1 There are occasions when the use of an unloading device can expose multiple faces and increase the access to materialfor sampling. One example is to use heavy equipment, such as an end loader, to remove outside material of a stockpile thusallowing increments to be
41、taken from a freshly exposed face. A second example is to have the end loader bucket remove primaryincrements from a stockpile and then manually subsample each increment with a manual sampling implement (see Fig. 1). A thirdexample is to have a clamshell bucket remove primary increments from a barge
42、 and then manually subsample each increment.7.6.2 Use of mechanical equipment such as auger samplers and core drill rigs are not in the scope of this procedure and areaddressed by other guides (Practice D4916) or working papers.FIG. 1 Commonly Used Manual Sampling ImplementsD6883 1737.7 In extremely
43、 cold weather, coal can become frozen on the surface as well as inside the stockpiles. It is preferable not tocollect increments manually from frozen coal. Wait until it thaws. If sampling is necessary while coal is frozen, make note of thecoals condition when it was sampled. It will be extremely di
44、fficult or even impossible to collect increments properly.8. Sampling Log8.1 Sampling technicians should keep a written log. A sampling log contains sample identification and also notations ofconditions encountered during increment collection. Entries to be noted include, but are not limited to: siz
45、e of stockpile, numberof railroad cars, barges, trucks or size segregation patterns, general configuration of stockpile, compaction of stockpile, perimeterconditions of pile, degree of contamination, the visual appearance of the material, date, and weather conditions.8.2 Any modifications to a sampl
46、ing plan should be discussed with the interested parties, if possible.Any changes to the agreedupon sampling plan are to be documented on the sampling log. If it is not possible or feasible to discuss modifications, both thefact that discussion was not possible, and the actual modifications that wer
47、e made, are to be documented on the sampling log.9. Personnel9.1 Sampling technicians using this practice should be instructed in the particular manual sampling practice agreed upon.9.2 Field situations often dictate on-site modifications of sampling plans. Modifications of a sampling plan should be
48、 made onlyby personnel with an understanding of and a sense of responsibility for the potential effects that the deviations will have on thesample being taken.10. Precision and Bias10.1 The samples obtained using this practice are non-probability samples and as such they cannot be used to calculatem
49、eaningful statistical inferences such as the levels of precision and bias. The user of this practice is referred to Practice E105 forfurther information concerning probability sampling of materials.11. Keywords11.1 barges; manual sampling; rail cars; railroad cars; stockpilesAPPENDIXES(Nonmandatory Information)X1. SAMPLING PATTERN SELECTIONX1.1 Increment PositionsX1.1.1 Sampling pattern and increment placement should be agreed upon by all concerned parties. To determine potentialpositions of increments, use of one of the following options is recommended:X1.1.2 Opt
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