![Jis M 8109 1996 For Nickel [PDF]](https://pdfs.asia/img/200x200/jis-m-8109-1996-for-nickel.jpg)
16 0 802 KB
Metode Sampling dan Metode Penentuan Kadar Air dari Bijih Nikel Garnierit
JIS M-8109-1996
Versi Inggris oleh Japanese Industrial Standard prepared by OMIC (H. Kanazawa = Privat e Translation)
August, 1996
JIS M 8109-1996
Bijih Nikel Garnierite – Metode Sampling, Preparasi Sampel dan Penetuan Kadar Air
Sekop Spesifikasi metode JIS berikut bertujuan untuk menetukan kadar rata-rata
dan
kandungan
kelembapan
air
dari
bijih
nikel
grnierite,yang selanjutnya disebut “ore”. (1) Metode Pengambilan Sampel (2) Metode preparasi sampel untuk tes kelembapan sample dan kadar
sampel (3) Metode kadar kandungan kelembapan (4) Metode pengukuran kadar kelembapan dan massa kering dari lot
Keterangan : 1. Standar ini, sesuai peraturan, mengacu pada JIS M 8100 2. Metode yang relevan dengan standar ini ditetapkan standar berikut :
dalam
JIS M 8100, JIS M 8126, JIS Z 8401, JIS Z 8801
Standar yang berlaku : JIS M 8100 – Aturan Umum untuk Metode Sampling Material Ruah dari Produk Tambang JIS M 8126 – Metode Penentuan Nikel pada Bijih JIS M 8129 – Metode Penentuan Kobalt pada Bijih JIS Z 8401 – Aturan Untuk Pembulatan Nilai Numerik JIS Z 8801 – Saringan Untuk Keperluan Pengujian
1
JIS M 8109-1996
DEFINISI ISTILAH Definisi beberapa istilah yang digunakan dalam standar ini adalah sebagai berikut: (1)
Lot A quantity of ore agreed upon between the parties concerned for the purpose of determining the average of the ore. The quantity of ore constituting a lot is called the size of the lot. Banyaknya jumlah bijih yang disepakati antara pihak-pihak yang bersangkutan untuk tujuan menentukan rata-rata bijih. Jumlah bijih yang terdapat di lot disebut ukuran dari lot.
(2)
Sub-lot The average of the ore consisting of part of lot as divided, when required, into appropriate quantities.
Rata-rata dari bijih terdiri dari bagian dari lot yang terbagi, bila diperlukan, dalam jumlah yang sesuai.
(3)
Increment A quantities of ore taken by a sampling device, as a rule in a single motion, from lot or sub-lot. A unit quantity of ore taken from a sample by the increment reducing method is also call an increment. The weight of a increment is called the size of the increment. Sebuah
jumlah
bijih
yang
diambil
oleh
perangkat
sampling,
sebagai aturan dalam gerakan tunggal, dari lot atau sub-lot. Sebuah unit kuantitas bijih yang diambil dari sampel dengan kenaikan mengurangi metode ini juga panggilan kenaikan. Berat selisih ini disebut ukuran selisih tersebut. (4)
Partial Sample The sample collecting on some increments, whet required, after preparation of each increment is taken is called the partial sample. Teknik
pengambilan
sampel
pada 2
beberapa
kenaikan,
mengasah
JIS M 8109-1996 diperlukan, setelah persiapan setiap kenaikan diambil disebut sampel parsial.
(5)
Belt Sampling When the lot is being moved by a belt conveyor the increment shall be taken from a surface of belt and from the discharged outlet of conveyor. Ketika banyak sedang dipindahkan oleh conveyor belt kenaikan tersebut harus diambil dari permukaan sabuk dan dari outlet habis conveyor.
(6)
Truck Sampling W h e n t h e lot is being handled by truck or wagon. Increment shall be taken from inside of truck or wagon.
Ketika banyak sedang ditangani oleh truk atau gerobak. Kenaikan harus diambil dari dalam truk atau gerobak.
3
JIS M 8109-1996
(7) Hatch Sampling
Increment shall be taken from inside handling implements when the let is being handled by such implements as grabs, buckets, sling tees, or freshly exposed surface of the ore in a lighter. Kenaikan penanganan
harus
diambil
ketika
mari
dari
sedang
dalam ditangani
mengimplementasikan oleh
alat
seperti
diperebutkan, ember, tee sling, atau baru terkena permukaan bijih dalam ringan. (8)
Composition Sample The general term of samples taken from lot or sub-lot for the purpose of determining the average grade of the composition. A sample taken from a prepared sample of a composition analysis sample. Istilah umum sampel yang diambil dari banyak atau sub-banyak untuk
tujuan
menentukan
nilai
rata-rata
komposisi.
Sampel
diambil dari sampel disiapkan sampel analisis komposisi. (9)
Moisture Sample A general term of samples taken from a lot or sub-lot for the purpose of decerminir4 the average moisture content. A sample taken for determining moisture content,
prepared by crashing and
reduction, and subject to measurement is called a moisture measurement sample. Sebuah istilah umum sampel yang diambil dari banyak atau subbanyak untuk tujuan decerminir4 kadar air rata-rata. Sampel diambil untuk menentukan kadar air, disiapkan oleh menabrak dan pengurangan,
dan tunduk pada
pengukuran disebut sampel
pengukuran kelembaban.
(10) Split-Used Sample
The split-use a sample signifies that the sample is divided into parts
and
employed
for
the
characteristics. 4
measurement
of
two
or
more
JIS M 8109-1996 Perpecahan-menggunakan sampel menandakan bahwa sampel dibagi menjadi beberapa
bagian dan digunakan untuk pengukuran dua
atau lebih karakteristik.
(11) Multiple-Used Sample
The multiple-use a sample signifies that the entire sample is employed in the determination of one characteristic, and thereafter, the same sample in the entirety or part is employed for the determination of another characteristic. The multi-menggunakan sampel menandakan bahwa seluruh sampel yang digunakan dalam penentuan satu karakteristik, dan setelah itu, sampel yang sama di keseluruhan atau sebagian digunakan untuk penentuan karakteristik lain.
(12) Maximum Particle Size
The size of the mesh of a sieve corresponding to a sieve having a 5% oversize residual factor for the sample. The sieve of this standard shall, as a rule, conform with JIS Z 8801. Ukuran mesh saringan sesuai dengan ayakan dengan faktor sisa kebesaran 5% untuk sampel. Saringan dari standar ini harus, sebagai suatu peraturan, sesuai dengan JIS Z 8801.
5
JIS M 8109-1996
A SYMBOL This standard is employed following the symbol.
Standar ini digunakan mengikuti simbol N
:
N
: Ukuran lot atau berat lot
n
:
n
: Jumlah yang diambil sampel dari satu lot
𝜎
:
Σ
Size of the lot or lot weight Number of the taken sample from one lot Precision indicated by the standard deviation
: Presisi diindikasikan dengan standar deviasi
𝜎𝑏 :
Dispersion among primary sampling units or among strata
e xpressed by the standard deviation 𝜎𝑤
: Dispersion among the increments in the primary sampling units or in the stratum expressed by the standard deviation
𝜎𝑠 :
Sampling precision expressed by the standard deviation
𝜎𝑝 :
Preparation precision expressed by the standard deviation
:
Including preparation and analysis or measurement precision expressed by the standard deviation
:
Including sampling, preparation, analysis or measurement precision expressed by the standard deviation (Composite precision)
4.
GENERAL ITEMS
4.1
A Summary of Sampling and Sample Preparation A Summary of sampling and sample preparation are as follows (Fig. 1) (1)
The size of lot shall be decided, thereafter meet the size of lot number of sub-lot shall be decided.
(2)
The meet of maximum particle size and the quality variation of characteristic shall be decided on method of sampling and number of increment. 6
JIS M 8109-1996 (3)
Be taken increment, thereafter increments be collected and co re partial sample.
(4)
This partial sample are crushed, reduced then shall be made composition analysis sample and moisture measurement sample.
7
JIS M 8109-1996
Fig. 1 Summary of Sampling and Sample Preparation (An Example)
4.2
The Handling of Samples Throughout the handling, preparation, and measurement of the sample, attention shall be paid to prevent change in quality or loss
of the sample
and all apparatus shall be kept
scrupulously clean to prevent foreign substances mixing with the sample. (1) Sample container: Sample Container shall be as follow: a) Container to be employed for the purpose of transporting or storing various sample shall be hold the entire quantity of the sample, be clean and strong, and shall be capable of being closed or sealed. b) In particular, it is necessary that the container for moisture samples shall be airtight and made of non-hygroscopic material, and also the interior of the container shall not be corroded. Remark: straw and jute bags are not suitable as containers for moisture sample.
8
JIS M 8109-1996
(2) Packing and marking of prepared composition analysis sample Prepared samples shall be sealed in container which shall be coated with aluminum foil or Poly-ethylene bag and these shall be sealed in paper bag and forwarded, distributed, or stored. The package shal1, as a rule, be the following items. a) Name of the Commodity (Brand) b) Name of the lot (Ship's name) and size c) Number of sub-lot d) Date of sampling and preparation e) Name of factory of sampling and preparation f) Name of in charge of sample preparation g) Other necessary information (3) Storing of samples Storing of the samples shall be as follows: (a) Prepared sample in accordance with (2) shall be stored as a rule, for 6 months (b) When storing samples, to prevent any change in quality, sample shall be sealed in a container and attention paid to the place of stage to exclude any effects of temperature, direct sunlight and moisture (4) Forwarding of sample Sample other than the composition sample shall not, as a rule, be forwarded, provided that, when forwarding can not be avoided, the forwarding method shall be decided by consultation between the parties concerned.
4.3
Determination of Average Quality For the nickel content, analysis shall be performed on each sub-lot accordance with JIS M 8126, and mean valve of this analysis shall be taken as the average quality of the sub-lot. The average quality of the lot is determined by calculating the weighted average value
9
JIS M 8109-1996
of the sub-lot down to three decimal places and rounding off the result to two decimal places. For moisture content, the value obtained from the method specified in 5. Method of determination moisture content shall be taken as the value for the lot.
4.4
Rounding off of Numerical Value Numerical value shall be rounded off is accordance with JIS Z. 8401.
4.5
Other Item Other item shall be performed as follows: (1) The necessary item shall be not specified on this standard. This item shall be decided by consultation between the parties concerted. (2) In case it is considered difficult to apply a part of specification of this standard. The method based on the agreement between parties concerned may be used in place of this specification. (3) Check experiment of the sampling method shall, as a rule, be performed according to Appendixes V, VI and VII. Examination shall be made to determined whether the specified accuracy is being maintained with change in handling process of lot, or whether there is any bias of contents.
5.
KIND OF SAMPLING
5.1
The Size of lot and Sub-lot As a rule, the size of one lot shall be the quantity of one shipment of ore that is contracted, although maximum size of sub-lot shall be within 5,000 tons.
10
JIS M 8109-1996
5.2
Characteristics and Accuracy
5.2.1 Characteristics The characteristics having accuracy specified shall be, as a rule, the nickel and moisture contents. 5.2.2 Overall accuracy The value of overall accuracy shall be expressed Table 1. Table 1 Overall Accuracy (2 )
Characteristics
30,000 More 45,000 Less
Size of lot (t) 20,000 More 10,000 More 30,000 Less 20,000 Less
10,000 Less
Ni-Contents %
0.025
0.030
0.040
0.050
H2O Contents %
0.5
0.6
0.8
1.0
5.2.3 Sampling accuracy The value of sampling accuracy shall be expressed Table 2. Table 2 Sampling Accuracy (2 )
Characteristics
30,000 More 45,000 Less
Size of lot (t) 20,000 More 10,000 More 30,000 Less 20,000 Less
10,000 Less
Ni-Contents %
0.020
0.024
0.032
0.040
H2O Contents %
0.48
0.58
0.76
0.94
11
JIS M 8109-1996
5.3
Classification of the Magnitude Variation The magnitude of the grade variation of ore shall be classified as shown in Table 3 for nickel content and shown in Table 4 for moisture content.
Table 3 Classification of Magnitude of Variation (Nickel Contents) Unit: % Classification
𝜎𝑤
𝜎𝑏
Large
0.25 or More
0.15 or More
Medium
0.15 More 0.25 Less 0.05 More 0.15 Less
Small
0.15 Less
0.05 Less
Table 4 Classification of Magnitude of Valuation (Moisture Contents) Unit: % Classification
𝜎𝑤
𝜎𝑏
Large
5 or More
3 or More
Medium
3 More
Small
5 Less
1 More
3 Less
3 Less
1 Less
Remarks: 1. The magnitude of grade variation shall be determined according to Appendix Ⅲ and Ⅳ of JIS M 8100. 2. When the magnitude of ore is unknown, as a rule, the subject shall be treated as having a “large” grade variation until identified.
5.4
Timing of Execution of Sampling The time for taking increments shall be as follow: (1) When the lot is being delivered and/or moved (2) In a period immediately before or after weighing the lot as possible
12
JIS M 8109-1996
5.5
Kind of Sampling The kind of sampling shall be the following three. (1) Belt sampling (2) Truck sampling (3) Hatch sampling
5.6
Increment
5.6.1 Size of increment The size of increment shall be the mass specified in Table 5, according to the maximum particle size of the increment. Remarks: When sampling, the increment of approximately uniform size shall he taken. Approximately uniform signifies that the dispersion of the increment size, aim expressed. As a coefficient of variation, is less than 20%. 5.6.2 Increment sampling devices (1)
Increment sampling scoop As a rule, increment-sampling scoops of the dimensions specified in Table 5 shall be used, according to the maximum particle size of the lot.
13
JIS M 8109-1996
Table 5 Scoop for Increment Taking & Sample Reduction Max. Scoop Particle Size number
Dimensions
Capacity b/c
a
b
c
d
e
f
(Approximately)
g thick
150
150
450 190 450 380 170
3
0.42
35,000
125
125
380 160 380 320 150
3
0.42
21,000
100
100
300 130 300 260 120
3
0.43
11,000
70
71
200 100 200 170 80
2
0.50
3,700
50
50
150 75 150 130 65
2
0.50
1,600
40
40
110 65 110 95
2
0.59
730
30
31.5
90
50
90
80
40
2
0.56
380
20
22.4
80
45
80
70
35
2
0.56
270
15
16
70
40
70
60
30
2
0.57
180
10
10
60
35
60
50
25
1
0.58
120
5
5
50
30
50
40
20
1
0.60
70
3
2.8
40
25
40
30
15
0.5
0.62
35
1
1
30
20
30
25
12
0.5
0.67
16
0.25D
0.25
15
10
15
12
8
0.3
0.67
2
Suitable
Suitable
50
Remark: 1. When use these scoop for the increment reduction, use the scoop without triangular edge (e=0) and append D at the right side of scoop number. 2. The scoop number 0.25D shall be used only for reduction of increment. (2)
14
JIS M 8109-1996
Mechanical Sampling devices (a) Installation of equipment The mechanical sampler shall be installed at a point where the entire quantity of a lot shall pass when lot is moved. Remark: For example, the sampler shall be installed at the discharged outlet of the main belt conveyor and there is a sampler of cutter type. (b) Sampler The opening of sampler shall be of a dimensional size (as a rule, 3 or more time the maximum particle size of a lot) capable of easily taking particles of the maximum particle size of a lot. Furthermore, the sampler shall be of a structure preventing the overflowing of the sample from container, and clogging of the chute. (c) Sampling interval It is desirable chat the sampler shall be capable of varying the sample interval. (d) Safety Sufficient cares shall be taken on the safety of workers in designing and installing the mechanical sampling apparatus. (e) Maintenance and monitoring The mechanical sampler apparatus should preferably be so constructed that the maintenance and cleaning are easy throughout all the system such as sampler, conveyor, hopper, crusher, etc. and its material are corrosion proof. Further, each function should preferably he easily monitored during operation.
15
JIS M 8109-1996
(f) Check of bias After installing the mechanical sampling apparatus, it is necessary for the mechanical sampling to confirm as soon as possible that the sample taken by this apparatus are free from bias. Remark: Check experiment of the sampling shall, as a rule, be performed according to the Appendix 6 of JIS M 8100. (g) Check of overall precision The mechanical sampling apparatus should preferably be so constructed that the check experiment of overall precision can be carried out easily. Remark: As a rule, Appendix 5 of JIS M 8100 (3)
Other sampling devices (a) The increment shall be free from bias, (b) The capacity shall be not less than that of Table 5.
5.6.3 Number of taking increment The minimum required number of increments taken from lot shall be specified according to kind of sampling 5.9.2, 5.10.2 and 5.11.2. 5.6.4 Method of taking increment Use the sampling devices specified in 5.6.2. (1) Take the increment at random by one working action so that the size of increment shall become nearly uniform. however when it is difficult to take by one working action, the increment may be taken by several action from one place selected at random and these samples may be combined to constitute one increment. (2) Take the increment, as a rule, from the lot during handling.
16
JIS M 8109-1996
(3) Don’t change the sampling interval during sampling work of cue lot. Even when the taking specified number of increments has been finished, the increment shall be continuously taken at the specified interval without discontinuing the taking of increment as long as the material handling of lot is carried out continuously.
5.7
Collection of Increment Every quantity
(about 100-500t)
shall be collected each
increment thereafter it become a partially sample and moisture and composition sample shall be prepared from these.
5.8
Split-use and Multiple-use of Sample The sample cm be used in split and, or' multiple for particle sample, for moisture content and for constituent, as required, when the sample is used in split for these purpose, the sample meeting the characteristics of largest number of increment shall be used, and when sample use for multiple be satisfied with follows. (1) After measuring of moisture sample is flied away easily. There are apparatus of prevention of flied away at crushing and reduction. (2) By check of experiment of sample, moisture and nickel content is not changed is confirmed.
5.9
Belt Sampling
5.9.1 Taking place of increment When the lot is moved by a belt conveyor, the increment shall be taken from the specified place on the belt or its chute.
17
JIS M 8109-1996
5.9.2 Number of Increment The minimum required number of increments taken from one lot shall be determined in accordance with Table 6. Table 6 Minimum Required Number of Increment Variation
Size of Lot (t) 10,000 Less
Large
Medium
Small
225
100
40
10,000 More
20,000 Less
360
160
65
20,000 More
30,000 Less
670
300
115
30,000 More
45,000 Less
900
400
160
5.9.3 Taking method of increment The taking method of increment shall be as follows: (1) Carry out the systematic sampling by the random start The sampling interval of increment shall be determined by dividing the size of lot N (for example, tonnage (t)) by number of increments n to be taken by round off the figures below decimal point. (2) When taking increment after the stopping belt conveyor, take the increment of quantity of not less than the specified size at the specified place of conveyor. In this case, cake the whole quantity along the moving direction of belt ranging over the full flow width of belt, which is not less than three times the maximum particle size as one increment. Remark: The full flow width signifies a cross section possessing a certain length (width) to, and approximately at right able to, the direction of movement of conveyor, or the direction of full at the chute when ore is being moved by belt conveyor.
18
JIS M 8109-1996
(3) When increments are taken from the belt conveyor is operating, a quantity equal or larger than the specified increment shall be taken covering the full flow width at chute of conveyor by sampler. Remark: When taking in the full flow width is impossible, after confirming that it is free from bias, selected a place at random is the full flow width at every tine when the increment be taken on the belt conveyor or its chute and take the increment by the specified sampler.
5.10
Truck sampling
5.10.1 Place take of increment Place take the increment from the truck and freight car under a lot handling 5.10.2 The Number of drawn truck on minimum required increment The first stage, the number of truck shal1 be drawn from Table 7. The second stage, two increments shall be taken from each drawn truck. Table 7 Minimum Required Number of Truck Between Size of Lot (t)
Large
Medium
Small
Within(𝜎𝑤 )
Within(𝜎𝑤 )
Within(𝜎𝑤 )
L
L
M
S
L
M
S
75
45
115
55
25
10,000 More 20,000 Less
340 240 195 220 120
75
185
85
35
20,000 More 30,000 Less
630 445 355 410 225 135 340 155 65
30,000 More 45,000 Less
850 600 480 550 300 180 460 210 85
10,000 Less
M
S
215 150 120 140
19
JIS M 8109-1996
5.10.3 Method of taking increments The method of taking increments shall be as follows: (1) The truck from which increments shall be taken shall be selected as the first stage of two-stage sampling. The method of selection shall be systematic sampling. (2) The interval of extracted trucks for raking increments shall be determined by dividing the size of lot with number of required truck and to be taken by round off figure below decimal point. (3) For taking increments from inside of truck, the places of sampling shall be selected at random and the increments shall be taken from surface of the cargo freshly exposed by handling. When the increment is taken from surface of the cargo when it is loaded on the truck, it shall be confirmed by check experiments that the increment is free from bias.
5.11
Hatch Sampling
5.11.1 Pace for taking increments Increments shall be taken from inside handling implements when the lot is being handled by such implements as grabs, buckets, sling net etc, or from a freshly exposed surface by handling of the cargo in a lighter. Instead of taking increment from inside the handling. implements sampling may be made after transferring to the ore of the implement to a flat place. Provided that, in this case, it shall be ascertained by check experiments that the sample is free from bias. 5.11.2 Number of increment taking The minimum required number of increments to be taken from one lot shall be as specified in Table 6. Provided that, when the number of increments taken from a single handling implement is two in 5.10.2. In case this, replace between number of truck and number of grab and from extracted grab shall be taken two increments.
20
JIS M 8109-1996
5.11.3 Method of taking increments Shall be as follows: (1) Carried out the systematic sampling by random start The sampling interval of increments shall be determined by dividing the size of lot with the number of required increments and to he taken by round off the figure below decimal point. (2) In case of taking increment from inside of hatch of freshly surface of cargo by handling, the place of taking increments shall be determined by at random.
6.
METHOD OF SAMPLE PREPARATION
6.1
The Sample Preparation The sample preparation are as follows: (1) Samples shall prepared by crushing and reducing partial sample as they pie (2) For composition samples, when necessary further drying shall be performed (3) For moisture content samples shall he prepared by further dividing partial sample into small sample quantities, and subjecting to increment reduction par sample taken from each of these small quantities. (4) When the composition sample and moisture sample are subjected to split or multiple uses, the preparation of the moisture sample shall conform to (3). (5) The reduction of sample shall be applied proper reduction method in accordance with in 6.5.6.
21
JIS M 8109-1996
(6) Care shall be taken so that during sample preparation a part of sample cannot be dispersed and dusts from surroundings and other foreign material cannot be mixed.
6.2
Accuracy of preparation Accuracy of preparation is as follows in Table 8. Table 8 Accuracy of Preparation ( )
Characteristics
Ni-Content
%
H2O Contents %
30,000 More 45,000 Less
Size of lot (t) 20,000 More 10,000 More 30,000 Less 20,000 Less
10,000 Less
0.011
0.013
0.017
0.021
0.11
0.16
0.22
0.32
Remarks: In regards to moisture, the accuracy of approximately 95%, probability is expressed by double the reduction analysis accuracy
6.3
Preliminary Drying Composition Sample When taken samples are more wet and to screen, crush and divide are very difficult. Samples may be solar-dried or dried in an oven at temperature 100℃ or less to an extert will not impede the use of the crusher or reducing devices.
6.4
Crushing of sample Crush the whole quantity of sample by an appropriate crusher up to the particle size that allows the whole quantity of sample to pass through the specified sieve. (1) Selection of crusher Select the crusher having the type and capacity suited for the particle size of sample to be ground, particle size of sample after crashing and physical properties (Note) of sample. 22
JIS M 8109-1996
Note
The physical properties are defined as hardness, rigidity, specific gravity, water content, stickiness, and others.
(2) Cleaning The inside of crusher shall be cleaned before the sample is supplied. (3) Preliminary cleaning When crushing the different sample from the sample which has been crushed at the last time, it should be preferable to pass as appropriate quantity of particulate materials taken from the lot previously through. (4) Taking of sample Take care to take out the whole sample remaining in the crusher. (5) Prevention of deterioration Take care to avoid the determination of sample due to the type of crusher or the heat generated by the long hours continuous operation and the like.
6.5
Reduction of Sample
6.5.1 Classification of redaction method (1) The reduction method shall be classified in to the following 4 methods shall be applied one method or this method in parallel. (a) Increment reduction method (b)
Method of riffle sampler
(c)
Method of toting and quartering
(d)
method using a reducer
(2) Reduction shall be performed on sample hiving at passage particle size of 22.4 mm or less.
23
JIS M 8109-1996
(3) Standard for reduction shall comply with 6.5.6. (4) The apparatus using for reduction shall be cleaned enough, when reduction of sample which is instead before reduction one, other samples taken from lot shall be had ready beforehand shall be used for cleaning. (5) During reduction of sample take care to avoid the deterioration, scattering and foreign material of sample. 6.5.2 increment reduction method (1) The size of shovel for the increment reduction and the thickness of the spread sample shall be as given in Table 9 according to the particle size of the sample. Remark
The pipe, etc can be used instead of increment reduction scoop. However, the inner diameter of pipe, according to the particle size of sample, in shown Table 5a. Samples shall be spread fit for pipe reading at bottom and taken sample; no fallen
Table 9 Particle Size of Sample and Scoop Size for Increment Reduction
Number of Scoop
Thickness of Sample Spread out ()
22.4 Less
20D
35~45
16.0 Less
15D
30~40
10.0 Less
10D
25~35
5.00 Less
5D
20~30
2.80 Less
3D
15~30
1.00 Less
1D
10~20
0.25D
5~10
Particle Size for Total Passage of Sample
250 𝜇 Less
24
JIS M 8109-1996
(2) The number of increments per sub-lot shall be 100 or more. provided that, when the total passage particle size of the sample is 10 mm or less and the sample is sufficiently dried to be thoroughly mixed, the number of increments per sub-lot shall be 20 or more. (3) When manually performing increment reduction of small samples, Attached Fig. I shall followed. (stage 1) The sample shall be spread uniform on a plain place in a rectangular with shown Table 9. (stage 2) The 2.ength shall he divided 4 and width 5. (stage 3) one increment shall be taken from each division, (in each division place be selected at random). Total 20 increment shall be taken which is be after reduction sample. When taking samples, the scoop shall be put into bottom of sample. Remarks 1. When a quantity of samples larger than the quantity of samples taken by the above method is required after reduction, the size of the increments shall be made larger, or the number of increments shall be increased. When increasing the number of increments, the number of divisions shall be increased or the number of increments taken from a single division shall be increased, but, the number of increments taken from each division shall be uniform. 2. When performing increment reduction, it is desirable that the increments be taken with the use of a backing plate. 6.5.3 Method using riffle sampler (1) According to the particle size of the sample, ate rule, a riffle sampler shown in Table 10 shall be used. 25
JIS M 8109-1996
Table 10 Particle Size and Types of Riffle Samplers Passage Particular Size ()
Riffle Sampler
Slot Width ()
Over
Under
16.0
22.4
50
50±1
10.0
16.0
30
30±1
5.00
10.0
20
20±1
2.80
5.00
10
10±0.5
2.80
6
6±0.5
(2) The riffle sampler shall be as follows: (a) An example of the structure and dimensions of various types of riffle samplers is shown in Attached Fig. 2. (b) The upright angle (e) included between the two sloping surfaces shall be 60 degrees or less. (c) The slots shall be of an even number and, as a rule, 16 or more. Provided that the number of slots of Nos. 50 and 30 types shall be 12 or more. (d) The sample receivers shall fit perfectly the outlets of the riffle sampler, and shall be of a structure preventing scattering of finely powdered ore. (e) The inner surfaces of the riffle sampler shall be smooth, and samplers with corroded surfaces shall not be used. (3) The samples and dropped to halve the at random to
shall be mixed, put into the container, uniformly down the main body of the sampler samples. One of the halves shall be selected be the reduced sample.
Remark: When using a riffle sampler, care must be taken to prevent clogging of the slots.
26
JIS M 8109-1996
(4) Me standards for reduction shall be as specified in 6.5.6. 6.5.4 Method of corning and quartering According to JIS M 8100 6.5.4. 6.5.5 Method using of reducer It shall be ascertained that the reducer has adequate accuracy and in free from bias. Standard of reduction shall be as specified in 6.5.6. Remark: The reducer shall be cleaned enough, when reduction of sample which is instead before reduction one, other samples taken from lot shall be had ready beforehand shall be used for cleaning. 6.5.6 Reduction standard The relationship between the particle size for total passage of sample and the weight of the sample after reduction shall be, as a rule, as given in Table 11. Provided that, in the case of increment reduction, 6.5.2 shall be follows. Table 11 Particle Size and Reduction Standard Weight of Sample Passage Particular Size after Reduction (kg) 22.4 Under
140 Min.
16.0 Under
70 Min.
10.0 Under
35 Min.
5.00 Under
8 Min.
2.80
Under
2 Min.
1.00
Under
0.5 Min.
420 𝜇 Under
0.1 Min.
250 𝜇 Under
0.05 Min.
Remarks: 1. This table be shown bulk density of sample is one. 27
JIS M 8109-1996
6.6
Preparation of Samples (for Composition) The preparation of samples (for composition) shall be as follows: (1) Partial samples shall be crushed finely to 150 or less and mixed well. From this the required number of 100g or more in weight samples shall be prepared, employing the increment reduction method or a reducer. (2) The above sample, placed in a polyethylene bag and sealed and further in a specified paper bag and sealed, shall be taken as prepared sample. (3) As a rule, composition sample shall be prepared four samples for shipper; buyer, umpire and reserve.
6.7
Preparation of Moisture Measurement Sample The moisture measurement sample shall be prepared as follows: (1) As a rule, 1 moisture measurement sample of 1 to 5 kg shall be prepared by the increment reduction method from partial samples for moisture content made by further subdividing the sub-lot and crushing separately to 22.4 mm or less. (2) Small samples for moisture content shall, as a rule, be reduced by the increment reduction method. In this case the number of increments shall comply with 6.3.2; and, if the specified quantity for a moisture measurement sample is satisfied, a scoop smaller by cue step compared to the grain size shown in. Table 5 may be used for the increment size. Remarks: Moisture measurement sample prepared by a reduction method employing a scoop 1 step smaller
shall
not
composition samples.
28
he
multiple-used
as
JIS M 8109-1996
7.
METHOD OF DETERMINATION OF MOISTURE CONTENT
7.1
Summary The moisture measurement sample prepared according to 6.7 is dried at a specified temperature until it becomes constant weight and the decrease in weight is determined, then the percentage
moisture
content
to
the
sample
weight
is
calculated.
7.2
Sample A moisture measurement sample prepared according to 6.7 is to be employed.
7.3
Apparatus The apparatus shall be as follows: (1) Drying container: The container shall be such that the thickness of the sample should be 30 mm of less. (2) Dry: The dryer shall be capable of maintaining the drying temperature of the sample at 105±5℃. (3) Scales: The scales shall have a reciprocal sensitivity of 1 five-thousandth or less of the sample weight.
7.4
Operation Operation shall conform to the following procedure.
29
JIS M 8109-1996
7.6
Decisive Value As to the moisture content of a sub-lot, to two, the weighted mean value according to the number of increments of the moisture content of the small samples for moisture which were determined in 7.5 should be calculated and rounded off to two decimal places. The weighted mean value according to the size of the sub-lots, rounded off to one decimal place, of the moisture content (%) of the sub-lots shall be the decisive value of the moisture content of the lot.
8.
METHOD OF DETERMINING THE DRY MASS The dry mass of a sub-lot shall be calculated from the following formula. Dry mass of sub~lot t = Weight of sub~lot t × 1−
Moisture content of sub~lot determined by 7.6 % 100
The decisive value of the dry mass of a lot is determined by, adding together the dry masses of the sub-lots of 1 lot and, as a rule, rounding off to four significant figures.
30
JIS M 8109-1996
Type No. 50
No. 30
No. 20
No. 10
No. 6
12
12
16
16
16
A
50±1()
30±1()
20±1()
10±0.5()
6±0.5()
B
630
380
346
171
112
C
250
170
105
55
40
D
500
340
210
110
80
E
300
200
135
75
60
F
50
30
30
20
20
G
340
340
210
110
80
H
200
140
85
45
30
I
640
390
360
184
120
J
220
220
140
65
55
K
220
220
140
65
55
L
340
300
210
110
80
M
250
170
105
55
40
N
75
55
35
20
15
O
340
300
210
110
80
P
630
380
346
171
112
Q
400
300
200
120
80
R
265
200
135
70
45
S
200
150
105
50
35
Symbol
No. of slots
Remarks: 1. No. 50 and No. 30 shall have 12 or more slots and No. 20, No. 10 and No. 6, not less than 16. A shows the specified dimensions of the slots. 2. The dimensions from B to S are shown only as examples.
31
JIS M 8109-1996
Attached Fig.1.
Increment Reduction Method (When Performed Manually) ( E xam pl e o f di vi d in g b y 2 0)
The crushed large sample is spread out rectangular to the thickness of Table 10 in this text.
The scoop is t hrust into the bottom and a scoopful of ore is taken from a division at random from t h e 2 0 e q u a l p a r t s . These are collected to form the sample.
32
JIS M 8109-1996 This is divided into 20 equal p a r t s . F o r e x a mp l e , i n t o 5 equal parts on the long side a n d 4 e q u a l p ar t s o n t h e short side.
③ Method of sampling using a backing plate.
33
JIS M 8109-1996
34
