ASTM C1075-93(1997)
(Practice)Standard Practices for Sampling Uranium-Ore Concentrate
Standard Practices for Sampling Uranium-Ore Concentrate
SCOPE
1.1 These practices are intended to provide the nuclear industry with procedures for obtaining representative bulk samples from uranium-ore concentrates (UOC) (see Specification C967).
1.2 These practices also provide for obtaining a series of representative secondary samples from the original bulk sample for the determination of moisture and other test purposes, and for the preparation of pulverized analytical samples (see Test Methods C1022).
1.3 These practices consist of a number of alternative procedures for sampling and sample preparation which have been shown to be satisfactory through long experience in the nuclear industry. These procedures are described in the following order. Stage Procedure Section Primary Sampling One-stage falling stream 4 Two-stage falling stream 5 Auger 6 Secondary Sampling Straight-path (reciprocating) 7 Rotating (Vezin) 8, 9 Sample Preparation 10 Concurrent-drying 11 to 13 Natural moisture 14 to 16 Calcination 17, 18 Sample Packaging 19 Wax sealing 20 Vacuum sealing 21
1.3.1 The primary and secondary sampling stages can be organized in the following way: PRIMARY SAMPLING (sections 4 to 6) ------------------------------------
General Information
Relations
Standards Content (Sample)
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Designation: C 1075 – 93 (Reapproved 1997)
Standard Practices for
Sampling Uranium-Ore Concentrate
This standard is issued under the fixed designation C 1075; 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 given stage, however, each procedure must be regarded as a
whole. It is highly inadvisable to mix elements belonging to
1.1 These practices are intended to provide the nuclear
different procedures.
industry with procedures for obtaining representative bulk
1.4 These procedures do not include requirements for
samples from uranium-ore concentrates (UOC) (see Specifica-
health, safety, and accountability. The observance of these
tion C 967).
practices does not relieve the user of the obligation to be aware
1.2 These practices also provide for obtaeining a series of
of and to conform to all applicable international, federal, state,
representative secondary samples from the original bulk
and local regulations pertaining to processing, shipping, or
sample for the determination of moisture and other test
using uranium-ore concentrates. (Guidance is provided in CFR,
purposes, and for the preparation of pulverized analytical
10, Chapter 1.)
samples (see Test Methods C 1022).
1.5 The values stated in SI units are to be regarded as the
1.3 These practices consist of a number of alternative
standard. The values given in parentheses are for information
procedures for sampling and sample preparation which have
only.
been shown to be satisfactory through long experience in the
1.6 This standard does not purport to address all of the
nuclear industry. These procedures are described in the follow-
safety problems, if any, associated with its use. It is the
ing order.
responsibility of the user of this standard to establish appro-
Stage Procedure Section
priate safety and health practices and determine the applica-
Primary Sampling One-stage falling stream 4
bility of regulatory limitations prior to use.
Two-stage falling stream 5
Auger 6
2. Referenced Documents
Secondary Sampling Straight-path (reciprocating) 7
Rotating (Vezin) 8, 9
2.1 ASTM Standards:
Sample Preparation 10
C 967 Specification for Uranium Ore Concentrate
Concurrent-drying 11-13
C 1022 Test Methods for Chemical and Atomic Absorption
Natural moisture 14-16
Calcination 17, 18
Analysis of Uranium-Ore Concentrate
Sample Packaging 19
2.2 Other Document:
Wax sealing 20
CFR 10 Nuclear Materials Licensing Code of Federal Regu-
Vacuum sealing 21
lations, Chapter 1
1.3.1 The primary and secondary sampling stages can be
organized in the following way:
3. General Requirements
3.1 Material Requirements:
3.1.1 The uranium-ore concentrates shall be free-flowing
and of a particle size not to exceed 6 mm (0.25 in.) or such
other limit agreed upon between contracting parties.
3.1.2 The average moisture content shall not exceed 5.0 %
weight of the uranium-ore concentrates.
3.1.3 The material shall be shipped to the sampling plant in
1.3.2 It is possible to combine the various elements of these
200-L (55-gal) standard steel drums that are fitted with steel
stages in different ways to give satisfactory results depending
lids and equipped with suitable gasket and sealing rings to
on the agreed requirements of the contracting parties. For a
ensure weatherproofing. The drums shall be constructed so that
the top of the drum is fully open when the lid is removed.
These practices are under the jurisdiction of ASTM Committee C26 on Nuclear
Fuel Cycle and are the direct responsibility of Subcommittee C26.02 on Fuel and
Fertile Material Specifications. Annual Book of ASTM Standards, Vol 12.01.
Current edition approved April 15, 1993. Published June 1993. Originally Available from Superintendent of Documents, U.S. Government Printing
published as C 1075 – 86. Last previous edition C 1075 – 86. Office, Washington, DC 20402.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
C 1075
3.1.4 The number of drums in a sampling lot shall not freely at a uniform, controlled rate. All of the material in a lot
exceed 90 and the gross weight shall not exceed 45 metric tons passes through the system and is subject to incremental
(100 000 lb).
sampling.
3.1.5 A minimum number of drums in a sampling lot may be
4.2 Sampling Equipment Requirements:
established depending upon the sampling procedure used.
4.2.1 A schematic diagram of a typical falling-stream sam-
3.2 Sampling Equipment Requirements:
pling facility is shown in Fig. 1. Subsequent procedures are
3.2.1 Care shall be taken in the design and operation of the
described by reference to this equipment.
sampling and all associated equipment to minimize the ex-
4.2.2 The flow of material through the falling-stream system
changes of air between the atmosphere and the sampling
shall be controlled by a rotary valve discharging to the hopper
system. For obvious safety reasons dust-carrying internal air
or pan of the first stage vibrating feeder. The rate of flow should
must be prevented from escaping the system. This is achieved
−2 3 3
not exceed 4.5 3 10 ·m (1.6 ft )/min and also should be
by means of dust collectors. The latter, however, shall be
controlled so that the cutter obtains from the falling stream at
designed and operated in such a way that a minimum amount
−2 3 3
least 1 cut/2.8 3 10 ·m (1.0 ft ) of material.
of external air shall be allowed into the system. The purpose of
this is (1) to limit the exchanges of moisture between the
4.2.3 The first stage vibrating feeder should be adjusted so
atmosphere and the UOC and (2) to prevent a size-selective
that the depth of the material in the trough (pan) does not
dedusting. In any case, the amount of dust escaping the
exceed 50 mm (2.0 in.), and that the entire vertical cross
sampling operations must be kept to a minimum.
section of the falling stream is totally intercepted by the cutter
3.2.2 The scales for the gross and tare weighings of the
head.
drums shall be capable of reading to the nearest 0.2 kg (0.5 lb)
4.2.4 The samplers should be designed and constructed as
and shall be fitted with a print-out or data processing system, or
follows:
both. They shall have a capacity of 600 kg (1300 lb). The
4.2.4.1 Approximately 1 % of the falling stream shall be
weigh scale shall be calibrated and adjusted if required, at the
diverted by the cutter. With small lots (for example, less than
beginning, middle, and end of each lot weighed. Test weights
10 tonnes), however, a larger percentage may be implemented
shall be certified by a statutory authority and shall be traceable
in order to fulfill the requirements of the secondary sampling
to national or state standards.
stage.
3.2.3 All sampling containers shall be clean and dry before
usage. 4.2.4.2 The horizontal linear speed of cutter heads shall not
exceed 15 cm (6 in.)/s.
4. Primary Sampling, Falling Stream—1 % In One Stage
4.2.4.3 The width of the cutter head shall be no less than 30
4.1 Scope—The falling-stream procedure provides for re- mm (1.25 in.), that is, a minimum of five times the allowable
moving a large number of increments of the material as it falls particle size.
FIG. 1 Schematic Diagram of Falling-Stream Primary Sampler In One Stage
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
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C 1075
4.2.4.4 It is recommended that the cutter heads be con- 5. Primary Sampling, Falling Stream—1 % In Two
structed of stainless steel to improve their durability and Stages
reliability.
5.1 Scope—The falling-stream procedure provides for re-
4.2.4.5 The top edges of the cutter heads shall be beveled to
moving a large number of increments of the material as it falls
form knife edges.
freely at a uniform, controlled rate. All of the material in a lot
4.3 Procedure for Obtaining the Primary Sample:
passes through the system and is subject to incremental
sampling.
4.3.1 Clean and dry the tops of the drums if necessary,
transfer them by means of a roller conveyor to the weigh scale,
5.2 Special Sampling Equipment Requirements:
and record the gross weight to 60.2 kg (60.5 lb).
5.2.1 A schematic diagram of a typical falling-stream sam-
4.3.2 After the gross weights of the drums in a lot have been
pling facility is shown in Fig. 2. Subsequent procedures are
obtained, dump the contents of each drum into an elevated bin.
described by reference to this equipment.
4.3.3 Equip the dumper with a vibrator and a dust collector
5.2.2 The flow of material through the falling-stream system
designed and operated in accordance with 3.2.1.
shall be controlled by a rotary valve discharging to the hopper
4.3.4 After the drum is emptied, tare weigh the empty drum,
or pan of the first stage vibrating feeder. The rate of flow should
−2 3 3
lid, drum ring, and bolt.
not exceed 4.5 3 10 ·m (1.6 ft )/min and also should be
controlled so that the cutter obtains from the falling stream at
4.3.5 Equip the bin into which the drums are dumped such
−2 3 3
least 10 cuts/2.8 3 10 ·m (1.0 ft ) of material.
as to facilitate the flow control and the transfer of material from
the bin. The bin should have a conical bottom with a discharge
5.2.3 The first stage vibrating feeder should be adjusted so
opening or a size that will provide the desired flow.
that the depth of the material in the trough (pan) does not
exceed 50 mm (2.0 in.), and that the entire vertical cross
4.3.6 The rotary valve discharge is received on an elongated
section of the falling stream is totally intercepted by the cutter
vibrating feeder that uniformizes the flow rate.
head.
4.3.7 Remove a portion of the falling stream and receive it
in a convenient surge bin mounted on a weighing system. 5.2.4 The samplers should be designed and constructed as
follows:
4.3.8 The contents of the surge bin are then fed to the
secondary sampling system (see Sections 7-9). 5.2.4.1 Approximately 10 % of each falling stream shall be
diverted by each cutter.
4.3.9 Let the material not diverted by the cutter fall freely
into a second bin from which the drums may be refilled if so 5.2.4.2 The horizontal linear speed of cutter heads shall not
desired. exceed 15 cm (6 in.)/s.
FIG. 2 Schematic Diagram of Falling Stream
NOTICE: This standard has either been superceded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
C 1075
5.2.4.3 The width of the cutter head shall be no less than 30 6.2.2.1 A conical top fitted with a flow-control valve if the
mm (1.25 in.), that is, a minimum of five times the allowable reciprocating cutter procedure is to be used for secondary
particle size. sampling, or
5.2.5 It is recommended that the cutter heads be constructed 6.2.2.2 A plain lid fixed by a metal band and bolt closure if
of stainless steel to improve their durability and reliability. the Vezin procedure is to be used for secondary sampling.
5.2.6 The top edges of the cutter heads shall be beveled to 6.2.3 In order to achieve the operating limits required for the
form knife edges. auger-sampling system the following design parameters are
5.3 Obtaining the Primary Sample Procedure: recommended:
5.3.1 Clean and dry the tops of the drums if necessary, 6.2.3.1 The auger shall be constructed of suitable material
transfer them by means of a roller conveyor to the weigh scale, (for example, tool or stainless steel) and shall have the
and record the gross weight to 60.2 kg (60.5 lb). following dimensions:
5.3.2 After the gross weights of the drums in a lot have been (1) Auger Tube—The outside diameter shall be 50 to 60 mm
obtained, dump the contents of each drum into an elevated bin. (1.968 to 2.375 in.) and the inside diameter shall be 43 mm
5.3.3 Equip the dumper with a vibrator and a dust collection (2.375 to 1.687 in.).
designed and operated in accordance with the conditions of (2) Length of Auger Helix Within the Auger Tube, shall be
3.2.1.
approximately 1400 mm (55 in.).
5.3.4 After the drum is emptied, tare weigh the empty drum,
(3) Pitch of Helix, shall be approximately 25 mm (1 in.)
lid, drum ring, and bolt.
apart.
5.3.5 Equip the bin into which the drums are dumped such
(4) In operation, the end of the auger should protrude 6 to 25
as to facilitate the flow control and the transfer of material from
mm (0.25 to 1.0 in.) below the auger tube.
the bin. The bin should have a conical bottom with a discharge
6.2.3.2 The auger shall be made to have a minimum
opening of a size that will provide the desired flow.
clearance allowing free rotation within the auger tube. The
5.3.6 Set the rotary valve to deliver approximately 4.2 to
auger shall be capable of being rotated electrically and, when
−2
3 3
4.5 3 10 ·m /min (1.5 to 1.6 ft /min). This rate should not
operating, shall turn at approximately 240 r/min.
vary during the course of sampling of the entire lot.
6.2.4 The auger sampling system may be used as a single or
5.3.7 Remove a portion of the falling stream and divert it to
double facility depending on design. In the latter case, two
a second vibrating elongated feeder and cutter of similar design
drums are sampled simultaneously with the two augers feeding
with a reciprocating cutter.
a common hopper that discharges by means of a 75-mm (3-in.)
5.3.8 Direct the material diverted by the second stage cutter
flexible tube into a single sample drum of 200-L (55-gal)
to a tared primary sample container, and close with a suitable
capacity.
lid depending on the secondary sampling procedure to be used
6.3 Obtaining the Primary Sample Procedure:
(see Sections 7-9).
6.3.1 Clean and dry the tops of the drums if necessary,
5.3.9 Let the material not diverted by the first- and second-
transfer them by means of a roller conveyor to the weigh scale,
stage cutters fall freely into a second bin from which the drums
and record the gross weight to 60.2 kg (60.5 lb). Pass the
may be refilled if so desired.
drums to the auger cabinet which shall be fitted with dust
5.3.10 Since approximately 10 % of each falling stream is
extraction and filtration equipment.
diverted, the primary sample container will contain approxi-
6.3.2 Remove the bolt and band from the drum, followed by
mately 1 % of the en
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