1、INTERNATIONAL STANDARD IS0 10277 First edition 1995-03-l 5 Aluminium ores - Experimental methods for checking the precision of sampling Minerais alumineux - Mbthodes expkrimentales de contr6le de la fide/it6 d j = 1 and 2, stands for final samples A, B, and A, B, respectively. c) Calculate the mean
2、and the range for each pair of duplicate samples: I;, = + (Tjl, + Xi2.) . . (3) R, = 13, - q2,1 . . (4) d) Calculate the mean and the range for each pair of gross samples, A and B: x=+ g1 ,+g2., . . (5) = R, = 6. -+.I . . (6) e) Calculate the overall mean and the mean of ranges (El, -5 single measur
3、ement of a final sample A, prepared from a gross sample A; X,1 single measurement of a final sample B prepared from gross sample B. b) Calculate the mean and the range for each pair of duplicate measurements: 5=+x1 +x2) . . . (16) 4 = crl - 21 (17) c) Calculate the mean and the range for each selec-
4、 ted pair of measurements, x1 and x3, or 2 and xs, selected at random: i=+(x,+nj)or +(x2+x4 R2 = Crl - sl or 1x2 - %I . (18) . . (19) d) Calculate the mean and the range for each pair of gross samples, A and B, selected at random: T = + (x1 + x4), + (+ + x4) or (20) (21) e) Calculate the overall mea
5、n and the mean of ranges ( + A2 = (R minimum 7 000 t; maximum 13 000 t Sampling details Maximum particle size of lots: 110 mm Type of increment: Unit mass of ore on belt conveyor; for its full cross-section over a certain length of flow Nominal mass of increment: 25 kg Number of increments: Stop bel
6、t conveyor at specified tonnage intervals of ore discharge, and collect all ore with a shovel on the belt at the specified location to obtain a 25 kg increment Preparation of samples Method of constituting gross samples: Place alternately individual increments taken successively in containers A and
7、B, and constitute gross samples A and B, each comprising 50 increments. Mass of gross samples: Mean 1 250 kg; minimum 1 220 kg; maximum 1 285 kg Type of dividing of gross samples: Division-testing type 1 (duplicate samples) Mesurements of AI,O, % (m/m) Statistic Experimental results Commercial deter
8、mination Found at loading point Mean 51,lO - - Minimum 49,90 - - Maximum 53,02 - - Estimated precision of sampling % (m/m) of Al,O, : d 0-l U-J ON 0 d ” d 6 d m 2 d E 7 0 II cba s d 8 d E d II 11 Copyright International Organization for Standardization Provided by IHS under license with ISONot for R
9、esaleNo reproduction or networking permitted without license from IHS-,-,-IS0 10277:1995(E) Q IS0 52 51 50 4! ijf!Lb l “i J - - “% - _- 2- - - - - - - ;- UCL=S1,67 l . E X 51 l . . l . . CL = 51.1 . . . -v- LCL:50,53 0 D 50 0 R3 1 - UCL=O,991 I 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 LotNo.
10、(order of arrival) E x and R3 charts Key Data outside the control limits UCL Upper control limit CL Central line LCL Lower control limit Figure 5 - Example of control charts for mean and range (Graphical presentation of data in sheet 2) 12 Copyright International Organization for Standardization Pro
11、vided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Q IS0 IS0 10277:1995(E) Annex A (normative) Alternative method for analysis of experimental data When the data do not contain rogue values (see 7.1 .I) this alternative method may be
12、 used for ana- lysing the experimental data in place of the method specified in clause 6. A.1 Division-testing type 1 The estimated values of approximately 95 % prob- ability standard deviation (hereinafter referred to sim- ply as standard deviation) of sampling, division and measurement should be c
13、alculated in accordance with the procedure given below: a) Denote the pair of four measurements (such as AI,O, as a percentage by mass) of a pair of two duplicate samples, prepared from the two gross samples A and 8, as xlll, xl12, x121, x122 and +11, x212r -921, $22. b) Calculate the mean and the r
14、ange for each pair of duplicate measurements: T, = - ; k,l + 4,2) . (A.11 4 = I-Q - +I * . . (A4 where i = 1 and 2, stands for A and B respec- tively; j = 1 and 2, stands for final samples, A, B, and A, B, respectively. c) Calculate the mean and the range for each pair of duplicate samples: = x1 = +
15、 (31. + $2.) . . . (A.31 R, = 13, - q2.j . (A.4) d) Calculate the mean and the range for each pair of gross samples, A and B: x = + (-; +X2,.) . (A.51 R, = I:,. - ;I I VW e) Calculate the overall mean and the variance in ac- cordance with the sum of squares of the ranges: p 1 c E x=- x k . ix R: = I
16、T, - $,212 . . . (A.71 (A.81 Ix R; = I%, - q212 . (A.9) 1 g = - 8k c 4 (A.1 1) . . . 1 6; = - c 2 2k R3 where k is the number of lots. (A. 10) (A. I 2) (A.13) f) Calculate the estimated values of the variance of measurement (c,), preparation (G,) and sampling (g): A2 UM = 2: . . (A.14) g) Calculate
17、the estimated values of standard devi- ation of measurement (GM), preparation (GP) and sampling Gs). h) Compare the value of Gs thus obtained with the desired standard deviation of sampling (as) as given in IS0 8685. 13 Copyright International Organization for Standardization Provided by IHS under l
18、icense with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-IS0 10277:1995(E) 0 IS0 A.2 Division-testing type 2 The estimated values of standard deviation should be calculated in accordance with the procedure given below: a) Denote the four measurements as follo
19、ws: x1, -9: pair of duplicate measurements of a final sample A, prepared from gross sample A; single measurement of a final sample A2 prepared from gross sample A; single measurement of a final sample B prepared from gross sample B. b) Calculate the mean and the range for each pair of duplicate meas
20、urements: n = + (x, + .I$ . * . (A. 17) R, = 1x1 -x21 . . (A. 18) c) Calculate the mean and the range for each selec- ted pair of measurements, x1 and x, or x, and x, selected at random: F=+(x,+.Jor +($+xa) . (A.19) R2 = Ix1 - sl or 1% - -4 . (A.20) d) Calculate the mean and the range for each pair
21、of gross samples, A and B selected at random: F = + (x, + .x4), + (x2 + x4) or + 3+x4) . . . (A.21) R, = Ix, - x41, h -x41 or h - x,1 . . (A.22) e) Calculate the overall mean and the variances in accordance with the sum of squares of the ranges: p x=- ; 1 k c . . . 1 g = - 2k R c . . . 1 +- R; 2k c
22、. . . A2 1 u3 = 2k Ix R; . . . (A.23) (A.24) (A.25) (A-26) where k is the number of lots. f) Calculate the estimated values of the variance of measurement ): A2 A2 CTM = u, . . . (A.27) $2, = ; - $h . . (A.28) g = ; - ; . . . (A.29) g) Calculate the estimated values of standard devi- ation of measur
23、ement (GM), preparation (GP) and sampling Gs). h) Compare the value of L& thus obtained with the desired standard deviation of sampling (crs) as given in IS0 8685. A.3 Division-testing type 3 In this case, the estimated values of standard devi- ation of sampling, preparation and measurement are not
24、obtainable separately. Type 3 testing gives the overall standard deviation (GSPM): The estimated value of overall standard deviation shall be calculated in accordance with the procedure given below: a) Calculate the mean and the range for each pair of measurements: 2=$x, +A$ . . (A.31) R = Ix, - 21
25、. (A.32) where x, 2 are the measurements of final sam- ples A and B, respectively. b) Calculate the overall mean and the estimated value of overall variance in accordance with the sum of squares of the ranges: = 1 x=- k c . A2 1 ds, = - k c R2 . . where k is the number of lots. (A.33) (A.34) c) Calc
26、ulate the estimated value of overall standard deviation ($sPM). 14 Copyright International Organization for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Q IS0 ISO 10277:1995(E) Annex B (informative) Bibliogra
27、phy I PEARSON, ES. The application of Statistical Methods to Industrial Standardization and Qua/- ity Control. British Standards Institution (I 935). 2 ASTM Manual on Quality Control of Materials. American Society for Testing and Materials (I 951). 3 IS0 9033:1989, Aluminium ores - Determi- nation o
28、f the moisture content of bulk material. 4 IS0 10226:1991, Aluminium ores - Exper- imental methods for checking the bias of sam- pling. 15 Copyright International Organization for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without lice
29、nse from IHS-,-,-IS0 10277:1995(E) ICS 73.060 Descriptors: minerals and ores, alumlnlum ores, sampling, accuracy, statlstlcal analysis, experimental data Copyright International Organization for Standardization Provided by IHS under license with ISONot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
