1、Designation: C1075 10C1075 17Standard Practices forSampling Uranium-Ore Concentrate1This standard is issued under the fixed designation C1075; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in p
2、arentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These practices are intended to provide the nuclear industry with procedures for obtaining representative bulk samples fromuranium-ore concentrate
3、s (UOC) (see Specification C967).1.2 These practices also provide for obtaining a series of representative secondary samples from the original bulk sample forthe determination of moisture and other test purposes, and for the preparation of pulverized analytical samples (see Test MethodsC1022 and C18
4、43).1.3 These practices consist of a number of alternative procedures for sampling and sample preparation which have been shownto be satisfactory through long experience in the nuclear industry. These procedures are described in the following order.Stage Procedure SectionPrimary Sampling One-stage f
5、alling stream 4Primary Sampling One-stage falling stream 5Two-stage falling stream 5Two-stage falling stream 6Auger 6Auger 7Secondary Sampling Straight-path (reciprocating) 7Secondary Sampling Straight-path (reciprocating) 8Rotating (Vezin) 8, 9Rotating (Vezin) 9, 10Sample Preparation 10Concurrent-d
6、rying 11 13Natural moisture 14 16Calcination 17, 18Sample Packaging 19Wax sealing 20Vacuum sealing 211.3.1 The primary and secondary sampling stages can be organized in the following way:1.3.2 It is possible to combine the various elements of these stages in different ways to give satisfactory resul
7、ts depending onthe agreed requirements of the contracting parties. For a given stage, however, each procedure must be regarded as a whole. It ishighly inadvisable to mix elements belonging to different procedures.1.4 These procedures do not include requirements for health, safety, and accountability
8、. The observance of these practices doesnot relieve the user of the obligation to be aware of and to conform to all applicable international, federal, state, and localregulations pertaining to processing, shipping, or using uranium-ore concentrates. (Guidance is provided in CFR 10, Chapter 1.)1.5 Th
9、e values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1 These practices are under the jurisdiction ofASTM Committee C26 on Nuclear Fuel Cycle and are the direct responsibility of Subcommittee C26.02 on Fuel and FertileMaterial Specif
10、ications.Current edition approved Jan. 1, 2010Nov. 1, 2017. Published February 2010November 2017. Originally approved in 1986. Last previous edition approved in 20042010as C1075 93 (2004).C1075 10. DOI: 10.1520/C1075-10.10.1520/C1075-17.This document is not an ASTM standard and is intended only to p
11、rovide 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 only the current versionof t
12、he 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 States11.6 This standard does not purport to address all of the safety problems, if any, associated with its use. It i
13、s the responsibilityof the user of this standard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized princip
14、les 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 Standards:2C859 Terminology Relating to Nuclear
15、 MaterialsC967 Specification for Uranium Ore ConcentrateC1022 Test Methods for Chemical and Atomic Absorption Analysis of Uranium-Ore ConcentrateC1843 Test Method for Determining Moisture Content in Uranium-Ore Concentrate2.2 Other Document:CFR 10 Nuclear Materials Licensing Code of Federal Regulati
16、ons, Chapter 133. Terminology3.1 Except as otherwise defined herein, definitions of terms are as given in Terminology C859.4. General Requirements4.1 Material Requirements:4.1.1 The uranium-ore concentrates shall be free-flowing and of a particle size not to exceed 6 mm (0.25 in.) or such other limi
17、tagreed upon between contracting parties.4.1.2 The average moisture content shall not exceed 5.0 % weight of the uranium-ore concentrates.4.1.3 The material shall be shipped to the sampling plant in 200-L (55-gal) standard steel drums that are fitted with steel lidsand equipped with suitable gasket,
18、 sealing rings, and sealing bungs (if applicable) to ensure weatherproofing. The drums shall beconstructed so that the top of the drum is fully open when the lid is removed.4.1.4 The number of drums in a sampling lot shall not exceed 90 and the gross weight shall not exceed 45 metric tons (100 000lb
19、).4.1.5 A minimum number of drums in a sampling lot may be established depending upon the sampling procedure used.4.2 Sampling Equipment Requirements:4.2.1 Care shall be taken in the design and operation of the sampling and all associated equipment to minimize the exchangesof air between the atmosph
20、ere and the sampling system. For obvious safety reasons dust-carrying internal air must be preventedfrom escaping the system. This is achieved by means of dust collectors. The latter, however, shall be designed and operated in sucha way that a minimum amount of external air shall be allowed into the
21、 system. The purpose of this is (1) to limit the exchangesof moisture between the atmosphere and the UOC and (2) to prevent a size-selective dusting. In any case, the amount of dustescaping the sampling operations must be kept to a minimum.4.2.2 The scales for the gross and tare weights of the drums
22、 shall be capable of reading to the nearest 0.2 kg (0.5 lb) and shallbe fitted with a print-out or data processing system, or both. They shall have a capacity of 600 kg (1300 lb). The weigh scale shallbe calibrated and adjusted if required, at the beginning, middle, and end of each lot weighed. Test
23、 weights shall be certified by astatutory authority and shall be traceable to national or state standards.4.2.3 All sampling containers shall be clean and dry before usage.5. Primary Sampling, Falling Stream1 % In One Stage5.1 ScopeThe falling-stream procedure provides for removing a large number of
24、 increments of the material as it falls freelyat a uniform, controlled rate. All of the material in a lot passes through the system and is subject to incremental sampling.5.2 Sampling Equipment Requirements:5.2.1 Aschematic diagram of a typical falling-stream sampling facility is shown in Fig. 1. Su
25、bsequent procedures are describedby reference to this equipment.5.2.2 The flow of material through the falling-stream system shall be controlled by a rotary valve discharging to the hopper orpan of the first stage vibrating feeder. The rate of flow should not exceed 4.5 102m3 (1.6 ft3)/min and also
26、should be controlledso that the cutter obtains from the falling stream at least 1 cut/2.8 102m3 (1.0 ft3) of material.2 For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Sevice at serviceastm.org. For Annual Book of ASTMStandardsvolume information, refer t
27、o the standards Document Summary page on the ASTM website.3 Available from U.S. Government Printing Office Superintendent of Documents, 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http:/www.access.gpo.gov.C1075 1725.2.3 The first stage vibrating feeder should be adjusted so that th
28、e depth of the material in the trough (pan) does not exceed50 mm (2.0 in.), and that the entire vertical cross section of the falling stream is totally intercepted by the cutter head.5.2.4 The samplers should be designed and constructed as follows:5.2.4.1 Approximately 1 % of the falling stream shal
29、l be diverted by the cutter. With small lots (for example, less than 10 tons),however, a larger percentage may be implemented in order to fulfill the requirements of the secondary sampling stage.5.2.4.2 The horizontal linear speed of cutter heads shall not exceed 15 cm (6 in.)/s.5.2.4.3 The width of
30、 the cutter head shall be no less than 30 mm (1.25 in.), that is, a minimum of five times the allowable particlesize.5.2.4.4 It is recommended that the cutter heads be constructed of stainless steel to improve their durability and reliability.5.2.4.5 The top edges of the cutter heads shall be bevele
31、d to form knife edges.5.3 Procedure for Obtaining the Primary Sample:5.3.1 Clean and dry the tops of the drums if necessary, transfer them by means of a roller conveyor to the weigh scale, and recordthe gross weight to 60.2 kg (60.5 lb).5.3.2 After the gross weights of the drums in a lot have been o
32、btained, dump the contents of each drum into an elevated bin.5.3.3 Equip the dumper with a vibrator and a dust collector designed and operated in accordance with 3.2.14.2.1.5.3.4 After the drum is emptied, tare weigh the empty drum, lid, drum ring, and bolt.5.3.5 Equip the bin into which the drums a
33、re dumped such as to facilitate the flow control and the transfer of material from thebin. The bin should have a conical bottom with a discharge opening or a size that will provide the desired flow.5.3.6 The rotary valve discharge is received on an elongated vibrating feeder that stabilizes a consis
34、tent flow rate.5.3.7 Remove a portion of the falling stream and receive it in a convenient surge bin mounted on a weighing system.5.3.8 The contents of the surge bin are then fed to the secondary sampling system (see Sections 78 910).5.3.9 Let the material not diverted by the cutter fall freely into
35、 a second bin from which the drums may be refilled if so desired.6. Primary Sampling, Falling Stream1 % In Two Stages6.1 ScopeThe falling-stream procedure provides for removing a large number of increments of the material as it falls freelyat a uniform, controlled rate. All of the material in a lot
36、passes through the system and is subject to incremental sampling.6.2 Special Sampling Equipment Requirements:6.2.1 Aschematic diagram of a typical falling-stream sampling facility is shown in Fig. 2. Subsequent procedures are describedby reference to this equipment.6.2.2 The flow of material through
37、 the falling-stream system shall be controlled by a rotary valve discharging to the hopper orpan of the first stage vibrating feeder. The rate of flow should not exceed 4.5 102m3 (1.6 ft3)/min and also should be controlledso that the cutter obtains from the falling stream at least 10 cuts/2.8 102m3
38、(1.0 ft3) of material.FIG. 1 Schematic Diagram of Falling-Stream Primary Sampler In One StageC1075 1736.2.3 The first stage vibrating feeder should be adjusted so that the depth of the material in the trough (pan) does not exceed50 mm (2.0 in.), and that the entire vertical cross section of the fall
39、ing stream is totally intercepted by the cutter head.6.2.4 The samplers should be designed and constructed as follows:6.2.4.1 Approximately 10 % of each falling stream shall be diverted by each cutter.6.2.4.2 The horizontal linear speed of cutter heads shall not exceed 15 cm (6 in.)/s.6.2.4.3 The wi
40、dth of the cutter head shall be no less than 30 mm (1.25 in.), that is, a minimum of five times the allowable particlesize.6.2.5 It is recommended that the cutter heads be constructed of stainless steel to improve their durability and reliability.6.2.6 The top edges of the cutter heads shall be beve
41、led to form knife edges.6.3 Obtaining the Primary Sample Procedure:6.3.1 Clean and dry the tops of the drums if necessary, transfer them by means of a roller conveyor to the weigh scale, and recordthe gross weight to 60.2 kg (60.5 lb).6.3.2 After the gross weights of the drums in a lot have been obt
42、ained, dump the contents of each drum into an elevated bin.6.3.3 Equip the dumper with a vibrator and a dust collection designed and operated in accordance with the conditions of3.2.14.2.1.6.3.4 After the drum is emptied, tare weigh the empty drum, lid, drum ring, and bolt.6.3.5 Equip the bin into w
43、hich the drums are dumped such as to facilitate the flow control and the transfer of material from thebin. The bin should have a conical bottom with a discharge opening of a size that will provide the desired flow.6.3.6 Set the rotary valve to deliver approximately 4.2 to 4.5 102m3/min (1.5 to 1.6 f
44、t3/min). This rate should not vary duringthe course of sampling of the entire lot.6.3.7 Remove a portion of the falling stream and divert it to a second vibrating elongated feeder and cutter of similar designwith a reciprocating cutter.6.3.8 Direct the material diverted by the second stage cutter to
45、 a tared primary sample container, and close with a suitable liddepending on the secondary sampling procedure to be used (see Sections 78 910).6.3.9 Let the material not diverted by the first- and second-stage cutters fall freely into a second bin from which the drums maybe refilled if so desired.6.
46、3.10 Since approximately 10 % of each falling stream is diverted, the primary sample container will contain approximately1 % of the entire lot. In no instance shall the total sample weight vary more than6 5 %than 65 % of the calculated value for theequipment employed.FIG. 2 Schematic Diagram of Fall
47、ing StreamC1075 1747. Primary SamplingAuger Sampling Procedure7.1 ScopeThe auger-sampling procedure provides for the removal of a core sample of the material from each drum by meansof a tube that contains a rotating auger. Each drum of material passes through the system and is subject to individual
48、sampling.7.2 Special Equipment Requirements:7.2.1 The auger sampler shall be designed and constructed so that approximately 0.5 % weight of the ore concentrate iswithdrawn from each drum. Experience with a variety of uranium-ore concentrates show that a range from 0.3 to 0.7 % can beexpected. A sche
49、matic diagram of a typical auger-sampling facility is shown in Fig. 3. Subsequent procedures are described byreference to this equipment.7.2.2 A tumbler shall be provided that is capable of rotating the sample drum about its axis at approximately 25 r/min. Beforethe tumbling operation, the sample drum shall be closed with either of the following:7.2.2.1 A conical top fitted with a flow-control valve if the reciprocating cutter procedure is to be used for secondary sampling,or7.2.2.2 A plain lid fixed by a metal band and bolt closure if the
