«Key comparisons in the field of multiples and submultiples of the kilogram»

Transcription

1 FINAL REPORT: СООМЕТ.М.М-К5 «Key comparsons n the feld of multples and submultples of the klogram» (CООМЕТ 258/RU/2) V.S. Snegov, VNIIM, St.-Petersburg December Introducton Ths report summarzes the results of a comparson of Mass Standards conducted between four partcpatng members of Euro-Asan Cooperaton of Natonal metrologcal Insttutes (COOMET). The COOMET key comparsons are usually carred out on those schemes that was proposed and mplemented by the Consultatve Commttee for Mass and Related Quanttes of the CIPM. Measurement comparsons brng the laboratores a confdence n the measurement standards and lead to the nternatonal acceptance of the measurement standards. Ths comparson was arose from dscussons at the 9 th meetng of TC 1.6 "Mass and related quanttes on Aprl, 24, SMU, Slovaka. The comparson s nternally dentfed as CООМЕТ 258/RU/2 and KCDB dentfer has been attrbuted by the BIPM as COOMET M.M-K5. The purpose of the key comparson COOMET.M.M-K5 "Comparsons n the feld of multples and submultples of the klogram" s n comparng the results of measurements obtaned by the partcpants. Two weghts sets wth fve nomnal mass values: 2 kg, 2 g, 5 g, 1 g and 2 (OIML Class E1) were used as transfer standards. These nomnal values were chosen as they followed the second phase of comparson ССМ.M-K5. All-Russan D.I. Mendeleyev Research Insttute for Metrology, VNIIM was the plot laboratory as well as a lnk to the laboratory to the CCM comparsons. The comparson was carred out from May 215 to July 28. In 27, measurements were carred out by Kazakhstan Insttute of Metrology (RSE "") on hs own ntatve (letter /6225 of 11/14/7). 2. Partcpants Four Natonal metrology nsttutes (s) of COOMET Member- Countres took part n the comparson. They are lsted n Table 1. Table 1 Laboratory Country Acronym Russan Scentfc Research Insttute of Metrology DI Mendeleev (Plot laboratory) Russa VNIIM Natonal Scentfc Center "Insttute of Metrology", Kharkov Ukrane Belarusan State Insttute of Metrology Belarus BelGIM Kazakhstan Insttute of Metrology Kazakhstan

2 Measurements Schedule No. Name of Date of measurements 1 VNIIM May 25 2 BelGIM September 25 3 September 26 4 May 28 5 VNIIM July 28 3 Transfer standards 3.1 Reference mass standards Two weghts sets wth fve nomnal mass values: 2 kg, 2 g, 5 g, 1 g and 2 (OIML Class E1) were crculated among the partcpants. The transfer standards were provded by company "SARTOGOSM", St. Petersburg. Each of the transfer standard sets comprsed fve non-magnetc stanless steel weghts and accordng to OIML, metrologcal and techncal characterstcs of them were not worse than Class E 1. Each set of transfer standards were placed n the weght boxes and then placed n a carton box. Transportaton was undertaken by hand. The metrologcal and techncal characterstcs of weghts are presented n Table 2. Table 2 Nomnal value, g ,2,2 Notes: Markng Shape Volume, cm 3 Densty, g/cm 3 Susceptblty, χ or magnetzaton, µт,2,2,2,2 2,5 2,5 2,5 «5» None Cylnder Cylnder 253,63 253,81 7,8855 7,8799 «*» Cylnder 24,646 8,1149 None Cylnder 25,49 7,8712 «*» Cylnder 6,331 7,8976 «**» Cylnder 6,328 7,914 «1» Knob,1265 7,951 None Cylnder,1266 7,8989 2,5 «*» Sheet,253 7,951 2,5 None Sheet,253 7,951 2,5 1. Densty values obtaned from the sheet of materal. 2. Temperature coeffcent of thermal expanson was taken equal to 4,8 1-5 о С Packng The transfer standards are packed n separate cases. They are shown n Fg. 1. Ths packng s usually used for precson weghts class E. 2

3 Fg.1 Measurng nstruments used by the partcpants Balances comparators VNIIM СС2 (Max= 2 kg, d=,1 ); СС1S (Max=1,5 g, d=,1 ); СС5 (Max=52 g, d=,1 ); UMX5 (Max=5,1 g, d=,1 ) BelGIM VLO-5kg-1(Max= 5 kg, d=,78 ); АТ15 (Max= 119 g, d=,1 ); АХ 16 (Max=111 g, d=,1 ); С5S (Max=5,2 g, d=,1 ) АХ124 (Max=12 kg, d=,1 ); АТ15 (Max=119 g, d=,1 ); АТ16/А (Max=111 g, d=,1 ); UMX5 (Max=5,1 g, d=,1 ); С51 (Max=51 g, d=,5 ); С1S (Max=1,5 g, d=,2 ) СС5 (Max=52 g, d=,1 ) Devces for measurng the densty of the ar VNIIM Thermometer - Multchannel dgtal thermometer,,2 о С Barometer BOP-1,,5 hpa Hygrometer Ratronk, 1% BelGIM Thermometer BIT-2,,2 о С Barometer - BRC-1М-2,,3 hpa Hygrometer BIT-2, 6 % Thermometer Fluke 162A,,4 o C Barometer MES-2А, 2,9 hpa Hygrometer - Fluke 162A,,5 % Thermometer TL-19,,1 о С Barometer СР-А,,2 hpa Hygrometer МВ-4М, 5 % 3

4 standards The reference mass standards of partcpants whch were used n measurements are shown n Table 3. Table 3 Nomnal Markng Mass u c, Volume, сm 3 2 kg No /5 1 kg-,7,2 124,1495 No kg-,2964,2 125, g No /5 2,575 g,8 25,45 5 g No /5 5,125 g,5 6,361 VNIIM 1 g No /5,9999,1,127 2 No. 9 2,33,1-2 kg KGRS-1 kg No. 5 1 kg + 2,24,25 126,454 1 kg Е 1 No kg +,23,25 126,454 2 g RS-111 No. 13 2,48 g,1 25,291 5 g RS-111 No. 13 5,383 g,5 6,3227 BelGIM 1 g RS-111 No. 13 1,61 g,1, MGО-1а No ,5,1,253 2 kg RS kg, 23,5 126,795 1 kg Е1 No kg +,41,6 126, g 2 g No ,6 g,2 24, g 5 g No ,26 g,1 6, g 1 g No ,2 g,2, No.1593,231 g,8,253 2 kg «1» knob 1 kg +,56,2 124,1 «1» cylnder 1 kg +,952,16 125,458 2 g none 199, g, «*» 199, g,1 25,94 5 g none 5,7 g,2 6,273 none 49, g,2 6,273 1 g «/» 1,2 g,1,125 «//», g,2,125 2 none, g,2,25 none,22 g,2,25 4. The results of comparsons reported by the partcpants The comparsons results of the transfer standards are presented by the partcpants: the actual mass and the combned uncertanty are gven n Tables 4 and 5. Here m-m s a measured dfference n mass of transfer standard from ts nomnal value, u c - combned uncertanty (k = 1). The results of the plot laboratory VNIIM are also presented as the results of a laboratory. 4

5 Table 4 2 kg 2 g 5 g VNIIM «5» None «*» None «*» «**» m- m u c m- m u c m- m u c m- m u c m- m u c m- m u c 6,6,1 5,64,1 -,8,11 -,288,11,121,5.134,5 BelGIM 5,83,22 5,69,22 -,5,3 -,258,3,7,5,9,5 6,11,6 5,52,6 -,83,4 -,289,4,124,4,136,4 6,25,15 5,4,15 -,81,11 -,36,11,123,6,136,6 Table 5 1 g 2 Cylnder Knob «*» None m- m u c m- m u c m- m u c m- m u c VNIIM -,751,5,614,5 -,65,1,11,1 BelGIM -,72,18,64,18 -,6493,18 -,1,18 -,747,8,622,8 -,6491,8 -,11,8 -,75,18,62,18 -,648,18,1, Stablty of the transfer standards The changes n the mass of transfer standards that have occurred over the tme of the comparsons have been measured n VNIIM, and they are shown n Table 6. In general, these changes are small and have the order of the component uncertanty of measurement results estmated by type A. Table 6 Nomnal Instablty mass m, µg u c, µg value, m, g Wth markng Wthout Standards markng ,3,5,2 -,7 +,8,2,1 Table 7. Repeatablty of the mass measurement results of transfer standards to VNIIM Date 2 kg 2 g 5 g 1 g 2 «5» none «*» none «*» «**» C K «*» none ,6 5,59 -,79 -,284,119,131 -,752,61 -,6496, ,3 5,67 -,8 -,288,122,134 -,749,61 -,65, ,95 5,69 -,82 -,292,123,136 -,747,61 -,652,13 Average value val value 6, 5,64 -,8 -,288,121,134 -,75,61 -,6499,1 S(d),6,5,2,4,2,3,3,,3,3 5

6 4.3 KCRV The equvalence degrees of VNIIM were calculated as per results of the CCM.M-K5 comparson as t s presented n Table 8. These degrees of equvalence of VNIIM were calculated usng results 2 kg-jx, 2 g-jy, 1 g-jy and 2 -Jy from the CCM.M-K5 comparson as presented n Table 8. The VNIIM result for weght wth the nomnal value 5 g was not consstent wth KCRV, and thus the results of measurements n ths value have been excluded from the COOMET comparson report. Ths occurred due to changes n the laboratory of VNIIM. The mechancal mass comparator of VNIIM whch had been used for measurng 5 g n the CIPM key comparson was replaced to a electronc comparator. Therefore the reference value of CIPM comparson n ths value has not been calculated for RMO comparson. Table 8 Nomnal mass, m Equvalence, D VNIIM, 2 kg-jx,4,62 2 g-jy,26,13 5 g-jy -,478,144 1g-Jy -,156, Jy -,61,19 The degree of equvalence Expanded uncertanty, U(D VNIIM ), The standards equvalence degree for the partcpants was calculated accordng to the formula: D ( m m ) j ( m m ) + j =, (1) where = D s the equvalence degree for the mass of the measurement standard wth VNIIM -th of the nomnal value of the results of CIPM comparsons. Ths approach of lnkng the partcpants results to the degrees of equvalence of the lnkng laboratory n CCM.M-K5 s dfferent from the normal approach, whch would be to use the results of the lnkng laboratory n both CCM.M-K5 and COOMET.M.M-K5 to relate the partcpants results n COOMET.M.M-K5 to the KCRV of CCM.M-K5. In case of usng only one lnkng laboratory standard the uncertanty of the equvalence degree s calculated by the formula: u j 2 VNIIM ( D ) u ( m ) + u ( m ) + U ( D ) j = j j VNIIM VNIIM, (2) 4 where uj ( m j ) s the uncertanty of the measurement standard mass devaton from the nomnal value for -th standard of J-th nsttute; u ( m VNIIM ) s the uncertanty of the measurement standard mass devaton from the nomnal value for -th standard obtaned by VNIIM; U ( D VNIIM ) s the extended uncertanty of the equvalence degree of the -th mass standard obtaned by VNIIM n CIPM comparson. The equvalence degrees of the comparson partcpants are presented n Tables 9 and 1. 6

7 Table 9 2 kg «5» 2 kg None 2 g «*» 2 g None D j, U (m), D j, U (m), D j, U (m), D j, U (m), BelGIM -,226,48,54,48,33,64,33,64,54,24 -,116,24,,26,2,26,194,36 -,596,36,2,32 -,15,32 Table 1 1 g «C» 1 g «K» 2 «*» 2 None D j, U (m), D j, U (m), D j, U (m), D j, U (m), BelGIM,15,42,1,42,1,4 -,18,4 -,12,28 -,8,28,3,24 -,28,24 -,15,42 -,1,42,14,4 -,7,4 The degrees of equvalence, D j, of all the mass standards are presented at Fgures kg " 5 " E Fg. 2 7

8 2 kg"none" Fg. 3 2 g " * " kazinmetr Fg. 4 8

9 2 g"none" Fg. 5,6 1 g "C",4,2 -,2 -,4 -,6 Fg. 6 9

10 .6 1 g"k" Fg "*".4.2 RazInMetr Fg.8 1

11 2 "NONE" Fg Summary Informaton on the degree of Equvalence between partcpants s shown below: 2 kg: Fgures 2 and 3 show that all the values wth the uncertanty bands except one partcpant ntersect the reference lne. For ths partcpant, the average of the 2 kg 5 and 2 kg NONE results wth the uncertanty band ntersects the reference lne. 2 g: Fgures 4 and 5 show that all the values wth the uncertanty bands ntersect the reference lne. 1 g: Fgures 6 and 7 show that all the values wth the uncertanty bands ntersect the reference lne. 2 : Fgure 8 and 9 shows that all the values wth the uncertanty bands ntersect the reference lne. 6. Acknowledgements The authors would lke to acknowledge the postve contrbuton of the followng people, partcpated n organzng and carryng out the measurements n COOMET.M.M-K5 comparson: Irna Koloznska, NSC IM, Ukrane; Evgeny Galat and Lyudmla Evseevch, BelGIM, the Republc of Belarus, Chngs Kuanbaev and Dnara Mukasheva,, the Republc of Kazakhstan. 11