Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Designation: E617 − 13
Standard Specification for
Laboratory Weights and Precision Mass Standards 1 This standard is issued under the fixed designation E617; the number immediately following the designation indicates the year of original origin al adoption or, in the case of revis revision, ion, the year of last revision. revision. A number in paren parenthese thesess indicates the year of last reappr reapproval. oval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
NIST SP 811 Guide 811 Guide for the Use of the International System of Unit (SI) 2008 Edition NIST NIS T SP 1038 The Int Intern ernatio ational nal Sys System tem of Uni Units ts (SI (SI)) – Conversion Factors for General Use (May 2006) NISTIR 5672 Advanced 5672 Advanced Mass Calibration and Measurement Assura Ass urance nce Pro Progra gram m for Sta State te Cali Calibra bratio tion n Lab Labora orator tories ies (2012) NISTIR 6969 Selected 6969 Selected Laboratory and Measurement Practices to Support Basic Mass Calibrations (2012) NIST Technical Note 1297 (1994) 1297 (1994) Guidelines for Evaluating and Exp Expres ressin sing g the Unc Uncerta ertaint inty y of NIS NIST T Mea Measur sureme ement nt Results
1. Sco Scope pe 1.1 Thi Thiss spe specific cificatio ation n cov covers ers wei weight ghtss and mas masss stan standar dards ds used in laboratories, specifically classes 000, 00, 0, 1, 2, 3, 4, 5, 6 and 7. Thi Thiss spe specific cificatio ation n rep replace lacess Nat Nation ional al Bur Bureau eau of Standards Circular 547, Section 1, which is out of print. 1.2 This specification specification contains the principal physical physical char char-acteristics and metrological requirements for weights that are used. 1.2.1 For the verification of weighing instruments instruments;; 1.2. 1. 2.2 2 Fo Forr th thee cal calib ibra ratio tion n of we weig ight htss of a lo lowe werr cla class ss of accuracy; accurac y; and 1.2.3 With weighing weighing instruments. instruments.
2.3 OIML Standards: 4 OIML OI ML D 28 Conventional 28 Conventional Value of the Result of Weighing in Air (2004) OIML R111–1e04 Weights R111–1e04 Weights of classes E1, E2, F1, F2, M1, M1–2 M1 –2,, M2 M2,, M2 M2–3 –3 an and d M3 Pa Part rt 1: Me Metr trol olog ogica icall an and d Technical Requirements (2004)
1.3 Maxim Maximum um Permissible Errors Errors (formerly tolerances) tolerances) and design restrictions for each class are described in order that both individual weights or sets of weights can be chosen for appropriate applications. 1.4 1. 4 Th Thee va valu lues es sta stated ted in SI un units its are to be re rega gard rded ed as standard.
2.4 BIPM Standards: VIM: JCGM 200:2012 International 200:2012 International Vocabulary of Metrology–Basic and General Concepts and Associated Terms GUM: GU M: JCG JCGM M 10 100: 0:20 2008 08 Eval Evaluati uation on of Meas Measurem urement ent Data–Guide to the Expression of Uncertainty in Measurement
1.5 Weight manufacturer manufacturerss must be able to prov provide ide evidence that all new weights comply with specifications in this standard (e.g., material, density, magnetism, surface finish, mass values, uncertainties). Statements of compliance by calibration laboratories during subsequent calibrations must meet the requirements of ISO/IEC 17025, 5.10.4.2 and indicate on the calibration report which sections have or have not been assessed.
2.5 EURAMET Standards: EURAMET/cg-18/V.. 3.0 EURAMET/cg-18/V 3.0 G Guid uidelin elines es on the Cali Calibra bration tion of Non-Automatic Weighing Intruments (2011)
2. Referenc Referenced ed Documents Documents
2.6 Additional Reference Documents: CIPM-2007 Revised CIPM-2007 Revised Formula for the Density of Moist Air, A. Picard, R. S. Davis, M. Glaser, and K. Fujii
2.1 ISO Standards: 2 ISO/IEC 17025 General 17025 General Requirements for the Competence of Testing and Calibra Calibration tion Labor Laboratorie atoriess (200 (2005) 5) 3 2.2 NIST Standards: NIST Handbook 143 State Weights and Measures Laboratories Program Handbook (2007)
3. Terminology 3.1 Definitions of Terms Specific to This Standard: 3.1.1 accurac class ass of we weig ight htss th that at accuracyy clas classs of weig weights hts— — a cl meets certain metrological requirements intended to keep the errors within specified limits.
1
This specification specification is under the jurisd jurisdiction iction of ASTM Commi Committee ttee E41 on Laboratory Apparatusand is the direct responsibility of Subcommittee E41.06 Subcommittee E41.06 on Weighing Devices. Current edition approved May 1, 2013. Published July 2013. Originally approved in 197 1978. 8. Las Lastt pre previo vious us edi editio tion n app approv roved ed in 200 2008 8 as E61 E617 7 – 97 (20 (2008) 08).. DOI DOI:: 10.1520/E0617-13. 2 Available from International Organization for Standardization (ISO), 1, ch. de la Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http://www.iso.org. 3 Available from National Institute of Standards and Technology (NIST), 100 Bureau Dr., Stop 1070, Gaithersburg, MD 20899-1070, http://www.nist.gov.
3.1.2 balance— instument instument indicating apparent mass that is sensitive to the following forces:
4
Availab vailable le from Orga Organisat nisation ion Intern Internation ationale ale de Metro Metrologie logie Legale, 11 Rue Turgot, 75009 Paris, France.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
Download From http://bbs.infoe http://bbs.infoeach.com ach.com 1
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 Force due to gravity
F g 5 m · g
F b 5 v · ρ a · g 5
eee
F z 5 µ o
v
m
ρ
ρ a · g
( M 1 χ H H )
≠ H
d V ≠ z
Air buoyancy equal to the weight of the displaced air.
Vertical component of the magnetic interaction intera ction between the weight and the balance or the environment, or both.
(permanent) nent) magn magnetiza etization tion (M)— parameter 3.1.8.2 (perma parameter that specifies a magnetic state of material bodies such as weights, in the abs absens ensee of an exte externa rnall mag magneti neticc field (most gen genera erally lly,, magnetization is a vecotr whose magnitude and direction are not necessarily constant within the material). The magnetization of a body generates an inhomogeneous magnetic field in space and thus may produce magnetic forces on other materials.
H and M are are vectors; z is the vertical cartesian coordinate. If magnetic effects are negligible, i.e. the permanent magnetization ( M ) of the weight and the magnetic susceptibility ( χ ) are sufficiently small, and the balance is calibrated with reference weights of well-known mass, the balance can be used to indicate the conventional mass, mc, of a body under conventionally chosen conditions.
3.1.9 mass— physical physical quantity, which can be ascribed to any material object and which gives a measure of its quantity of matter. The unit of mass is the kilogram.
3.1.3 calibration (of weights)— the the acts of determining the mass difference between a standard of known mass value and an “unknown” test weight or set of weights, establishing the mass value and conventional mass value of the “unknown,” and of determining a quantitative estimate of the uncertainty to be assigned to the stated mass or conventional mass value of the “unkn “unknown,” own,” or both, and provi providing ding metrological metrological traceab traceabilility to the “unknown.”
metrological tracea traceability— bility— prop 3.1.11 metrological p roper erty ty of a mea measu sure re-ment result whereby the result can be related to a reference through throu gh a docum documented ented unbroken unbroken chain of calibr calibrations, ations, each contrib con tributin uting g to the mea measur suremen ementt unc uncert ertain ainty ty.. Met Metrol rologi ogical cal traceability requires an established calibration hierarchy. Elements for confirming metrological traceability to be an unbroken ke n ch chain ain to an in inte tern rnat atio iona nall me meas asur urem emen entt sta stand ndar ard d or a national measurement standard (IPK or NPS), shall include a documented measurement uncertainty, a documented measurement procedure, accredited technical competence, metrological traceability traceab ility to the SI, and established calibration calibration intervals (see current VIM: JCGM 200).
calibration n (genera (generally)— lly)— set 3.1.3.1 calibratio s et of op oper erat atio ions ns th that at establish, establis h, under specified conditions, the relatio relationship nship between values of quantities indicated by a measuring instrument or measuring system, or values represented by a material measure or a reference material, and the corresponding values realized by standards. certificate— ate— certificate 3.1.4 calibration certific certificate issued by calibra calibra-tion laboratories to document the results of a calibration. conventiona tionall mass— conventional 3.1.5 conven conventional value of the result of weighing in air, in accordance to International Recommendation OIML D 28. For a weight taken at 20°C, the conventional mass is the mass of a reference weight of a density of 8000 kg/m 3 which it balances in air of density of 1.2 kg/m 3.
3.1.6 correction— mass mass values are traditionally expressed by two numbers, one being the nominal mass of the weight, and the second being a correction. The mass of the weight is the assigned nominal value plus the assigned correction. Positive corrections indicate that the weight embodies more mass than is indicated by the assigned nominal value. Negative corrections tio ns in indi dica cate te th that at th thee we weig ight ht em embo bodi dies es les lesss ma mass ss th than an is indicat ind icated ed by the ass assign igned ed nom nomina inall valu value. e. The cor correc rection tion is equivalent to the “error.” internationa tionall pr prototy ototype pe kilog kilogram— ram— the 3.1.7 interna t he platin platinumumiridium irid ium cyl cylind inder er main maintain tained ed at the Int Intern ernatio ational nal Bur Bureau eau of Weig eights hts and Mea Measur sures es (BI (BIPM) PM),, at Sev Sevres res,, Fra France nce wit with h an internationally accepted defined mass of 1 kg.
3.1.8 magnetism— effect effect that generates an attractive or repulsive force. )— measure 3.1.8.1 (volume) magnetic susceptibility ( χ )— measure of the ability of a medium to modify a magnetic field. It is related to the magnetic permeability (µ) by the relation: µ/µ 0 = 1 + χ . The quantity quan tity µ/µ 0 is so some meti time mess re refe ferr rred ed to as th thee re rela lati tive ve permeability, µ r.
3.1.10 maximum permissible errors— the the maximum amoun amountt by which the sum of the conventional mass of the weight, its deviation from nominal value and its associated uncertainty is allowed to deviate from the assigned nominal value.
3.1.12 reference stand ndar ard, d, ge gene nera rally lly of th thee reference stand standar ard— d— a sta highest metrological quality available at a given location, from which measurements made at that location are derived. roughness parameter or R-pa R-parameter rameter (R a or R z)— 3.1.13 roughness parameter that describes the assessed roughness profile of a samp sa mple le.. Th Thee let letter ter R is in indi dica cativ tivee of th thee ty type pe of as asse sess ssed ed profi pr ofile le,, in th this is cas casee R fo forr ro roug ughn hnes esss pr profi ofile. le. Th Thee as asse sess ssed ed profile of a sample can be in terms of different profile types: a roug ro ughn hness ess pr profi ofile le or R-p R-para aramet meter er,, pr prima imary ry pr profi ofile le or P-parameter, a waviness profile or W-parameter.
3.1.14 set of weights— a series of weights, usually presented in a case so arranged to make possible any weighing of all loads between the mass of the weight with the smallest nominal value and the sum of the masses of all weights of the series with a progression in which the mass of the smallest nominal value weight constitutes the smallest step of the series. 3.1.15 temperature (t)— in in degrees Celsius, is related to the absolute thermodynamic temperature scale, called the Kelvin scale, by t = T – – 273.15 K. 3.1.16 test weight (mt )— weight weight that is to be tested according to this standard. tolerance nce test test— — verifica 3.1.17 tolera verification tion tha thatt the con conven ventio tional nal mass of the weights and their corresponding uncertainties as tested are correct within the maximum permissible errors of the respective weight class.
3.1.18 uncertainty— non-negativ non-negativee parame parameter ter charac characterizin terizing g the dispersio dispersion n of the qua quanti ntity ty val values ues being attr attribu ibuted ted to a measurand, based on the information used.
Download From http://bbs.infoe http://bbs.infoeach.com ach.com 2
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 3.1.19 units— the the units used are: (1) for mass, the milligram (mg), the gram (g) and the kilogram (kg); (2) for density, the kilogram per cubic meter (kg m –3).
S y m b ol ∆ m c
Unit kg
3.1.20 U.S. National prototype standard— platinum-iridium platinum-iridium kilogram identified as K20, maintained at the National Institute of Standards and Technology, with value assigned relative to the Int Intern ernatio ational nal Pro Prototy totype pe Kilo Kilogra gram m pro provid vides es the Uni United ted States access to the mass unit.
m cr
kg
m ct m s m t n
kg kg kg –
3.1.21 weight— material material measure of mass, regulated in regard gar d to its phy physica sicall and met metrol rologi ogical cal cha charact racteri eristic stics: s: sha shape, pe, dimensions, material, surface quality, nominal value, density, magnetic magnet ic prop properties erties and maximu maximum m permis permissible sible error error..
p R a
Pa µm
R z
µm
r s s s 2 T
– – kg kg2 K
∆T*
°C
t t
– °C
U u u b u ba u c u d
kg kg kg kg kg kg
u E u F
kg kg m–3
u hr u inst
% kg
u ma u p u s
kg Pa kg
u t u w
°C kg
V z µ µ0
m3 m N A –2 N A –2
µ0M µr v eff
ρ ρ0
T – – kg m–3 kg m–3
ρa ρal
kg m–3 kg m–3
ρr
kg m–3
ρt χ
kg m–3 –
¯
NOTE 1—The term “weight” is also used as the physical quantity quantity of the gravitational force of a body. From the context it is usually clear in which sense the term is used. If the sense is not clear, one may use the words “weight force” or “weight piece,” depending on its meaning.
3.2 Symbols: S y m bo l A
Unit –
B
–
C D
– kg
d d 1
kg m
d 2
m
F b
N
F g F z
N N
g H hr I
m s–2 A m –1 % kg
∆I
kg
∆I 1
kg
∆I 2
kg
∆I s
kg
i
–
j
–
k M
– A m –1
m ∆m
kg kg
δm
kg
m 0
kg
m c ∆m c
kg kg
Definition represents weighing the reference weight in a weighing cycle represents weighing the test weight in a weighing cycle correction factor for air buoyancy difference of balance readings between minimum and maximum values from eccentricity test scale interval estimated distance between centers o f weights during loading estimated distance from the center of the load receptor to one of the corners air buoyancy equal to the weight of the displaced air gravitational force magnetic force between a mass comparator and a weight in the vertical or z-direction gravitational acceleration magnetizing field strength relative humidity indication of the weighing in st struments (scale division) indication difference of the balance, where ∆ I = = I t – I r indication difference using an automatic exchange mechanism with weights in first position indication difference using an automatic exchange mechanism with weights in reversed position c h a n g e i n i n d i c a ti o n o f b a l a n c e d u e t o sensitivity weight subscript used as an index in summations subscript for number of test weights or number of series of measurements coverage factor, typically 2 or 3 permanent magnetization (see also µ0M ) mass of a rigid body (weight) mass difference, usually between test and reference weight maximum permissible error on the weights mass, nominal value of the weight (e.g. 1 kg) conventional mass of the weight conventional mass difference between test weight and reference weight
Definition average conventional mass difference between test weight and reference weight conventional mass of the reference weight conventional mass of the test weight mass of the sensitivity weight mass of the test weight subscript for number of measurement sequences barometric pressure mean height of roughness profile (Rparameter) maximum height of roughness profile (R-parameter) subscript for reference weight subscript for sensitivity weight standard deviation variance thermodynamic temperature using the International Temperature Scale of 1990 (ITS-90) initial difference between weight temperature and laboratory temperature subscript for test weight temperature in degrees Celsius, where t = = T – 273.15 K uncertainty, expanded uncertainty uncertainty, standard uncertainty uncertainty of air buoyancy correction uncertainty of the balance combined standard uncertainty uncertainty due to the display resolution of a digital balance uncertainty due to eccentricity uncertainty of the formula used to calculate air densit density y uncertainty in relative humidity uncertainty due to instability of the reference weight uncertainty due to magnetism uncertainty in barometric pressure uncertainty due to the sensitivity of the balance uncertainty in temperature uncertainty due to the weighing process volume of a solid body (weight) vertical cartesian coordinate magnetic permeability magnetic constant (magnetic permeability of vacuum), µ0 = 4π × 10–7 N A–2 magnetic polarization relative magnetic permeability (µ/µ0) effective degrees of freedom mass of a rigid body (weight) density of air as a reference value equal to 1.2 kg m–3 density of moist air density of moist air during the last (previous) calibration of the reference weight density of a reference weight with mass m mass m r density of the weight being tested m a g n e ti c s u s c e p t i b i l i ty
4. Maximum Permissible Permissible Errors Errors 4.1 For each weight, weight, the expanded uncertain uncertainty ty U at at approximately 95 % confidence (See Section 9) of the conventional mass shall be less than or equal to one-third of the maximum permissible error given in Table in Table 1 as 1 as defined in Section 9.
3
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE 1 Maximum Permissible Errors
NOTE 1—Maximu 1—Maximum m Perm Permissibl issiblee Error Errorss are repor reported ted in SI units, typically typically millig milligrams rams.. NOTE 2—The “grain” is the same in avoirdupois, troy and apothecaries units of mass. NOTE 3—See NIST SP 811 and NIST SP 1038 for conversion and units of measure. Denomination Metric 50 0 0 k g 30 0 0 k g 20 0 0 k g 10 0 0 k g 50 0 k g 30 0 k g 20 0 k g 10 0 k g 50 k g 30 k g 25 k g 20 k g 10 k g 5 kg 3 kg 2 kg 1 kg 5 00 g 3 00 g 2 00 g 1 00 g 50 g 30 g 20 g 10 g 5g 3g 2g 1g 5 00 m g 3 00 m g 2 00 m g 1 00 m g 50 mg 30 mg 20 mg 10 mg 5 mg 3 mg 2 mg 1 mg 0.5 m g 0.3 m g 0.2 m g 0.1 m g 0 .0 5 m g Avoirdupois P o un d 10 00 0 l b 50 00 l b 30 00 l b 25 00 l b 20 00 l b 10 00 l b 5 00 l b 1 00 l b 50 l b 30 l b 25 l b 20 l b 10 l b 5 lb 3 lb 2 lb 1 lb 0 .5 l b 0 .3 l b 0 .2 l b
±mg except as noted Class 000
13 m g 7. 5 6 .2 5 5. 0 2. 5 1 .3 0 .7 5 0 .5 0 .2 5 0 .1 3 0. 07 5 0 .0 5 0. 02 5 0 .0 1 5 0 .0 1 4 0 .0 1 3 0 .0 1 0 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 2 0 .0 0 2 0 .0 0 2 0 .0 0 2 0. 00 2 0. 00 2 0. 00 2 0. 00 2 0. 00 2 0. 00 2 0. 00 2 0. 00 2 0 .0 0 2 0 .0 0 2 0 .0 0 2 0 .0 0 2 0 .0 0 2
Class 00
25 mg 15 1 2 .5 10 5 .0 2. 5 1 .5 1. 0 0 .5 0 .2 5 0 .1 5 0 .1 0 0 .0 5 0 .0 3 0 0 .0 2 6 0 .0 2 5 0 .0 2 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3 0 .0 0 3
Class 0
Class 1
63 m g 38 31 25 13 6. 0 3 .8 2. 5 1 .3 0 .6 0 0 .3 8 0 .2 5 0 .1 3 0 .0 6 0 0 .0 3 7 0 .0 3 7 0 .0 2 5 0. 01 7 0. 01 7 0. 01 7 0. 01 7 0. 00 5 0. 00 5 0. 00 5 0. 00 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0 .0 0 5 0. 00 5 Class 0 mg
125 mg 75 62 50 25 12 7 .5 5 .0 2 .5 1 .2 0 .7 5 0. 50 0 .2 5 0 .1 2 0. 07 4 0. 07 4 0. 05 0 0 .0 3 4 0 .0 3 4 0 .0 3 4 0 .0 3 4 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0. 01 0 0. 01 0 0. 01 0 0. 01 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 0 .0 1 0 Class 1 mg
57 m g 29 17 14 12 5 .5 2 .7 1 .7 1 .2 0. 55 0 .2 7 0 .1 7 0 .1 2
110 mg 57 34 28 23 11 5. 4 3. 4 2. 3 1 .1 0 .5 4 0 .3 4 0 .2 3
Class 2
Class 3
Class 4
Class 5
Class 6
Class 7
25 g 15 g 10 g 5g 2. 5 g 1. 5 g 1g 500 mg 25 0 15 0 12 5 10 0 50 25 15 10 5. 0 2 .5 1. 5 1. 0 0. 50 0. 25 0. 15 0. 10 0 .0 7 4 0 .0 5 4 0 .0 5 4 0 .0 5 4 0 .0 5 4 0 .0 2 5 0 .0 2 5 0 .0 2 5 0 .0 2 5 0 .0 1 4 0 .0 1 4 0 .0 1 4 0 .0 1 4 0. 01 4 0. 01 4 0. 01 4 0. 01 4 0 .0 1 4 0 .0 1 4 0 .0 1 4
50 g 30 g 20 g 10 g 5g 3g 2g 1g 50 0 m g 30 0 25 0 20 0 10 0 50 30 20 10 5 .0 3 .0 2 .0 1 .0 0 .6 0 0 .4 5 0 .3 5 0. 25 0 .1 8 0 .1 5 0 .1 3 0 .1 0 0 .0 8 0 0 .0 7 0 0 .0 6 0 0 .0 5 0 0. 04 2 0. 03 8 0. 03 5 0. 03 0 0 .0 2 8 0 .0 2 6 0 .0 2 5 0 .0 2 5 0. 02 5 0. 02 5
10 0 g 60 g 40 g 20 g 10 g 6. 0 g 4 .0 g 2 .0 g 1 .0 g 600 mg 50 0 4 00 200 10 0 60 40 20 10 6 .0 4 .0 2. 0 1 .2 0 .9 0 0 .7 0 0 .5 0 0 .3 6 0 .3 0 0 .2 6 0 .2 0 0 .1 6 0 .1 4 0 .1 2 0 .1 0 0. 08 5 0. 07 5 0. 07 0 0. 06 0 0 .0 5 5 0 .0 5 2 0 .0 5 0 0 .0 5 0 0. 05 0
25 0 g 1 50 g 1 00 g 50 g 25 g 15 g 10 g 5g 2 .5 g 1. 5 g 1. 2 g 1 .0 g 500 mg 25 0 1 50 1 00 50 30 20 15 9 5 .6 4. 0 3. 0 2 .0 1. 3 0 .9 5 0 .7 5 0 .5 0 0. 38 0. 30 0. 26 0. 20 0. 16 0. 14 0. 12 0. 10 0. 08 0 0. 07 0 0. 06 0 0. 05 0 0 .0 5 0
5 00 g 300 g 200 g 10 0 g 50 g 30 g 20 g 10 g 5g 3g 2. 5 g 2g 1g 500 mg 300 20 0 100 50 30 20 10 7 5 3 2 2 2 .0 2 .0 2 .0 1. 0 1. 0 1. 0 1. 0 0 .5 0 0 .5 0 0 .5 0 0 .5 0 0 .2 0 0 .2 0 0 .2 0 0 .1 0 0 .1 0
75 0 g 45 0 g 30 0 g 150 g 75 g 45 g 30 g 15 g 7. 5 g 4 .5 g 4 .5 g 3 .8 g 2 .2 g 1 .4 g 1 .0 g 7 5 0 mg 4 70 30 0 21 0 16 0 10 0 62 44 33 21 13 9. 4 7. 0 4. 5 3. 0 2. 2 1. 8 1. 2 0 .8 8 0 .6 8 0 .5 6 0 .4 0
Class 2 g & mg 23 g 11 g 7g 6g 4. 5 g 2. 3 g 1 .7 g 230 mg 110 68 56 46 22 11 6 .8 4 .6 2 .2 1 .1 0 .6 8 0 .4 6
Class 3 g & mg 45 g 22 g 14 g 12 g 9g 4 .5 g 2. 3 g 460 mg 22 0 1 40 110 92 44 22 14 9 .2 4 .4 2 .2 1. 4 0 .9 2
Class 4 g & mg 90 g 44 g 28 g 24 g 18 g 9g 4 .6 g 9 20 m g 4 40 26 0 22 0 1 80 88 43 27 18 8. 8 4 .3 2. 7 1 .8
Class 5 g & mg 22 7 g 113 g 68 g 57 g 45 g 23 g 11 g 2 .3 g 1 .1 g 68 0 m g 57 0 450 2 30 110 68 45 27 15 10 8 .1
Class 6 g & mg 45 4 g 2 27 g 1 36 g 113 g 91 g 45 g 23 g 4. 5 g 2 .3 g 1 .4 g 1 .1 g 91 0 m g 45 0 2 30 1 40 91 45 23 14 9 .7
Class 7 g & mg 680 g 34 0 g 2 04 g 1 70 g 136 g 68 g 34 g 6 .8 g 4 .1 g 3g 2. 5 g 2g 1 .3 g 7 60 mg 76 51 0 4 30 270 16 0 110 91
4
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE 1 Continued Denomination Metric 0 .1 l b 0 .0 5 l b 0 .0 3 l b 0 .0 2 l b 0 .0 1 l b 0 .0 0 5 l b 0 .0 0 3 l b 0 .0 0 2 l b 0 .0 0 1 l b 0 .0 0 0 5 l b 0 .0 0 0 3 l b 0 .0 0 0 2 l b 0 .0 0 0 1 l b 0 .0 0 00 5 l b 0 .0 0 00 3 l b 0 .0 0 00 2 l b 0 .0 0 00 1 l b Avoirdupois Ounce 10 o z 8 oz 5 oz 4 oz 3 oz 2 oz 1 oz 1 /2 o z 1 /4 o z 1 /8 o z 1 /1 6 o z 1 /3 2 o z 1 /6 4 o z 0 .5 0 o z 0 .3 o z 0 .2 o z 0 .1 o z 0 .0 5 o z 0 .0 3 o z 0 .0 2 o z 0 .0 1 o z 0.00 5 o z 0.00 3 o z 0.00 2 o z 0.00 1 o z 0.00 05 o z 0.00 03 o z 0.00 02 o z 0.00 01 o z Troy Ounce 1 00 0 oz t 5 00 o z t 3 00 o z t 2 00 o z t 1 00 o z t 50 o z t 30 o z t 20 o z t 10 o z t 5 oz t 3 oz t 2 oz t 1 oz t 0.5 o z t 0.3 o z t 0.2 o z t 0.1 o z t 0 .0 5 o z t 0 .0 3 o z t 0 .0 2 o z t 0 .0 1 o z t 0 .0 0 5 o z t 0 .0 0 3 o z t 0 .0 0 2 o z t
±mg except as noted Class 000
Class 00
Class 0
Class 1
Class 2
Class 3
Class 4
Class 5
Class 6
Class 7
0 .0 5 5 0 .0 2 7 0 .0 1 7 0 .0 1 7 0 .0 1 2 0 .0 0 7 5 0 .0 0 7 5 0 .0 0 7 5 0 .0 0 7 5 0. 00 9 0. 00 9 0. 00 9 0. 00 9 0 .0 0 9 0 .0 0 9 0 .0 0 9 0 .0 0 9 Class 0 mg 0 .4 0 .3 0 .1 8 0 .1 4 0 .1 2 0 .0 7 0 .0 4 0 .0 2 0 .0 1 5 0 .0 1 5 0 .0 1 3 0 .0 0 8 0 .0 0 6
0.11 0 .0 5 4 0 .0 3 4 0 .0 3 4 0 .0 2 3 0 .0 1 5 0 .0 1 5 0 .0 1 5 0 .0 1 5 0 .0 2 3 0 .0 2 3 0 .0 2 3 0 .0 2 3 0. 02 3 0. 02 3 0. 02 3 0. 02 3 Class 1 mg 0 .7 0. 6 0 .3 5 0 .2 8 0 .2 3 0 .1 3 0 .0 7 0. 04 0 .0 3 0 .0 2 9 0. 02 5 0. 01 5 0. 01 2
Class 1
0 .4 4 0. 36 0 .3 2 0 .2 3 0 .1 6 0. 14 0.11 0 .0 9 1 0 .0 6 8 0 .1 5 0 .1 5 0 .1 5 0 .1 5 0. 15 0. 15 0. 15 0. 15 Class 3 mg 2 .8 2 .3 1 .4 1 .1 0 .9 1 0 .6 4 0 .4 2 0 .3 0. 2 0. 16 0 .1 2 0 .0 9 5 0 .0 7 7 0 .3 0 .2 3 0 .1 9 0 .1 4 0.11 0. 09 5 0. 07 7 0. 06 4 0 .0 5 4 0. 05 0 .0 4 4 0 .0 3 8 0 .0 3 1 0 .0 2 9 0 .0 2 7 0 .0 2 6 Class 3 mg 31 0 m g 16 0 90 62 31 31 16 9 .1 6 .2 3 .1 1. 6 0 .9 1 0 .7 1 0 .4 5 0. 31 0. 24 0. 20 0. 15 0 .1 2 0 .0 9 7 0 .0 8 4 0 .0 7 1 0 .0 5 6 0 .0 4 9 0 .0 4 4
1 .1 0 .7 7 0 .5 9 0 .4 5 0 .3 4 0 .2 7 0 .2 2 0 .1 9 0 .1 5 0 .3 0 .3 0 .3 0 .3 0. 3 0. 3 0. 3 0. 3 Class 4 mg 5. 4 4 .5 2 .8 2 .3 1 .8 1 .3 0 .8 6 0 .5 9 0 .4 3 0 .3 1 0. 24 0. 19 0. 15 0 .5 9 0 .4 5 0 .3 8 0 .2 9 0. 23 0 .1 9 0 .1 8 0 .1 4 0.11 0 .0 9 5 0 .0 8 6 0 .0 7 7 0 .0 6 4 0 .0 5 9 0 .0 5 4 0 .0 5 Class 4 mg 6 20 m g 310 19 0 12 0 62 62 31 19 12 6 .2 3 .1 1 .9 1. 4 0 .9 1 0 .6 2 0 .4 9 0 .4 0 0 .3 0 0. 23 0 .1 9 0 .1 7 0 .1 4 0.11 0. 09 7 0. 09 1
5 .1 3 .0 2. 0 1. 8 1. 2 0. 86 0. 64 0 .5 0 0 .3 6 0. 9 0. 9 0. 9 0. 9 0. 9 0. 9 0. 9 0. 9 Class 5 mg 19 16 12 9 .5 8 .2 5 .9 3. 9 2. 5 1 .5 1. 1 0. 73 0. 5 0. 36 2 .5 1 .8 1 .4 0. 91 0 .6 4 0 .4 5 0.4 0. 0.3 0. 0 .2 3 0 .1 9 0. 16 0. 13 0.11 0 .0 9 5 0 .0 8 6 0 .0 7 3 Class 5 g & mg 1. 6 g 7 70 mg 77 4 70 3 10 160 77 47 35 21 12 8 .4 8. 6. 4 4. 2 2 .6 1 .9 1 .5 0. 97 0 .6 5 0 .4 9 0 .4 1 0 .3 1 0 .2 3 0. 19 0. 17
6 .8 4 .5 3. 2 2. 3 1. 4 0 .9 1 0 .9 1 0 .9 1 0 .9 1 3 3 3 3 3 3 3 3 Class 6 mg 45 23 16 11 8. 1 5. 4 3. 2 2 .3 1 .4 0. 91 0 .9 1 0 .9 1 0 .9 1 2.3 2. 1 .4 1. 0 .9 1 0 .9 1 0. 91 0 .9 1 0.91 0. 0.91 0. ** ** ** ** ** ** ** ** ** Class 6 g & mg 3 .2 g 1 .5 g 94 0 m g 62 0 32 0 15 0 94 58 32 32 16 9 .3 9. 8. 0 4 .2 2 .6 1 .9 2 .3 2. 0 2 .0 2 .0 1 .1 1 .0 1 .0 1 .0 0 .5 0
56 33 22 19 12 7 5 4 3
Class 0
0. 22 0.11 0. 06 8 0. 04 6 0. 03 4 0 .0 2 4 0 .0 2 4 0 .0 2 4 0 .0 2 4 0 .0 7 0 .0 7 0 .0 7 0 .0 7 0 .0 7 0 .0 7 0 .0 7 0 .0 7 Class 2 mg 1 .4 1. 2 0. 70 0. 55 0. 45 0. 26 0. 14 0 .0 8 0 .0 6 0 .0 5 8 0. 05 0 0. 03 0 0. 02 4 0. 08 0 0. 06 8 0. 05 7 0. 05 0 0. 05 0 0. 03 0 0. 02 3 0. 02 3 0 .0 2 3 0 .0 2 3 0 .0 2 3 0 .0 2 3 0. 02 3 0. 02 3 0. 02 3 0. 02 3 Class 2 mg 1 60 m g 80 45 31 16 8 4 .6 3 .1 1 .6 0 .8 0. 46
5
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Class 7 mg 32 0 1 80 1 60 110 73 48 28 25 9. 1 4. 3 4 .3 4 .3 4 .3 25 25 9 .1 9. 5 .9 4.3 4. 2.0 2. 2 .0 2. 2.0 2. 2.0 2. ** ** ** ** ** ** ** ** Class 7
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE 1 Continued Denomination Metric
±mg except as noted Class 000
Class 00
Class 0
Class 1
Class 2
Class 3
Class 4
Class 5
Class 6
0. 07 8 0 .0 6 5 0 .0 6 0 0 .0 5 6 0 .0 5 2 Class 4 g & mg 0 .3 1 g 0 .1 6 g 91 mg 62 31 16 9 .1 6 .2 3 .1 1 .6 1 .2 0. 91 0. 62 0 .4 4 0 .3 4 0 .3 0 .2 3 Class 4 mg 13 6 .5 3 .9 2 .6 1 .4 0 .9 1 0 .6 5 0 .5 7 0. 4 0 .3 0 .2 5 0 .2 1 0 .1 7 0. 14 0. 12 0.11 0 .0 9 1 0 .0 7 8 0 .0 7 1 0 .0 6 4 0 .0 5 6 0. 05 2 0. 05 1 0 .0 5 0 .0 5 Class 4 mg 20 12 8 .0 4 .0 2 .0 1 .3 1 .0 0 .7 0 .5 0 0 .4 0 0 .3 3 0 .2 6 0 .2 0 0 .1 7 0 .1 5 0 .1 2 0 .1 0 0 .0 8 9 0 .0 8 0 0 .0 7 0 0 .0 6 0
0. 14 0.11 0 .0 9 7 0 .0 8 4 0 .0 7 1 Class 5 g & mg 0 .7 8 g 0 .3 9 g 0 .2 3 g 0 .1 6 g 78 mg 41 28 21 12 7 .8 5 .3 4 .2 2 .6 1 .7 1 .3 0 .9 7 0. 65 Class 5 mg 36 22 15 11 6 .3 3 .2 2 .3 1 .4 0 .9 1 0 .9 1 0 .7 1 0 .5 8 0 .4 2 0 .3 1 0 .2 5 0 .2 2 0 .1 7 0. 14 0. 12 0.11 0 .0 9 1 0 .0 7 1 0 .0 7 1 0 .0 7 1 0 .0 7 1 Class 5 mg 50 36 27 15 9 6 4 .4 3 2 1 .4 1 0 .7 5 0 .5 0 .3 9 0 .3 2 0 .2 6 0 .2 0. 18 0. 15 0. 12 0. 1
0 .5 0 0. 50 0 .5 0 0 .5 0 0 .5 0 Class 6 g & mg 1 .5 g 0 .7 8 g 0 .4 6 g 0 .3 2 g 0 .1 6 g 82 m g 56 42 24 16 11 8. 4 5. 2 3 .4 2 .6 1 .9 1. 3 Class 6 mg 36 22 15 11 6 .3 3 .2 2 .3 1 .4 0. 91 0 .9 1 0. 71 0. 58 0. 42 0 .3 1 0 .2 5 0 .2 2 0. 17 0 .1 4 0 .1 2 0.11 0 .0 9 1 0 .0 7 1 0 .0 7 1 0 .0 7 1 0 .0 7 1 Class 6 mg 10 0 60 44 20 10 8 5 3 2 2 2 2 2 1 1 1 1 0. 5 0. 5 0. 5 0. 5
0 .0 0 1 o z t 0 .0 0 0 5 oz t 0 .0 0 0 3 oz t 0 .0 0 0 2 oz t 0 .0 0 0 1 oz t Pennyweight
Class 0
Class 1
Class 2
0 .0 3 8 0 .0 3 3 0 .0 3 0 0 .0 2 8 0 .0 2 6 Class 3
10000 dwt 5000 dwt 3000 dwt 2000 dwt 1000 dwt 500 dwt 300 dwt 200 dwt 100 dwt 50 dwt 30 dwt 20 dwt 10 dwt 5 dwt 3 dwt 2 dwt 1 dwt Grain
Class 0
Class 1
Class 2
Class 3
10 00 0 g r 5 0 0 0 gr 3 0 0 0 gr 2 0 0 0 gr 1 0 0 0 gr 5 00 g r 3 00 g r 2 00 g r 1 00 g r 50 gr 30 gr 20 gr 10 gr 5 gr 3 gr 2 gr 1 gr 0.5 g r 0.3 g r 0.2 g r 0.1 g r 0 .0 5 g r 0 .0 3 g r 0 .0 2 g r 0 .0 1 g r Carat
Class 0
Class 1
Class 2
Class 3 mg 10 6 .0 4 .0 2 .0 1 .0 0 .6 9 0 .5 2 0 .3 5 0 .2 5 0 .1 9 0 .1 6 0 .1 3 0 .1 0 0 .0 8 6 0 .0 7 5 0 .0 6 0 0. 05 0 0. 04 4 0. 04 0 0. 03 5 0 .0 3 0
500 0 c 300 0 c 200 0 c 100 0 c 5 00 c 3 00 c 2 00 c 1 00 c 50 c 30 c 20 c 10 c 5c 3c 2c 1c 0 .5 c 0 .3 c 0 .2 c 0 .1 c 0 .0 5 c
6
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Class 7
Class 7
Class 7
Class 7 mg 47 0 33 4 28 7 16 0 1 00 70 44 33 21 13 13 13 13 3 3 3 3 0 .8 8 0 .8 8 0 .8 8 0 .8 8
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE 1 Continued Denomination Metric
±mg except as noted Class 000
Class 00
Class 0
Class 1
Class 2
0 .0 3 c 0 .0 2 c 0 .0 1 c Apothecary Ounce 12 oz ap 10 oz ap 6 o z ap 5 o z ap 4 o z ap 3 o z ap 2 o z ap 1 o z ap Apothecary Dram 6 dr ap 5 dr ap 4 dr ap 3 dr ap 2 dr ap 1 dr ap Apothecary Scruple 2 s ap 1 s ap
4.1.1 For each weight, 4.1.1 weight, the con conven ventio tional nal mas mass, s, mc (determined with an expanded uncertainty), shall not differ by more than the dif differ ferenc ence: e: max maximu imum m per permiss missibl iblee err error or δm minus expanded uncertainty, from the nominal value of the weight, mo: m o 2 ~ δ m 2 U ! # ~ m c ! # m o 1 ~ δ m 2 U !
Class 3
Class 4
Class 5
Class 6
Class 7
0 .0 2 8 0 .0 2 7 0 .0 2 5
0 .0 5 6 0 .0 5 3 0 .0 5 0
0 . 08 0 . 07 0 . 06
0 .2 0 .2 0 .2
7 .5 4 .5 3. 5 3. 0 2. 5 1. 50 1. 00 0. 60
15 9 7 6 5 3 2 1 .2
45 36 23 18 16 11 9 .1 4 .5
2 90 2 80 184 144 128 110 91 40
0 .4 0 0 .3 0 0 .2 7 0 .2 0 0 .2 0 0 .1 7
0 .8 0 .6 0 .5 5 0 .4 0 .4 0 .3 5
3 .6 2 .7 2. 3 1 .8 1 .8 1. 4
36 27 23 18 18 14
0 .1 7 0 .1 5
0 .3 5 0 .3 0
1 .4 0 .9 1
14 9 .1
another. See Table See Table 2. 2. The shape of weights smaller than 1 mg shall be discussed and verified with the customer. 5.1.3 Class 1, 2, 3, 4, 5, 6 and 7 may be either Type Type I or Type Type II depending on the application. 5.2 Design— A weight may have any shape that does not introduce features that reduce the reliability. All weights shall be free of ragged or sharp edges or ends. Both sheet metal and wire weights shall be free of cracks such as may be formed from bending.
(1 )
4.2 Maxim Maximum um permissible permissible errors for classes classes 000, 00, 0, 1, 2, 3, 4, 5, 6 and 7 ar aree giv iveen in Table Table 1. These These maximu maximum m permissible errors apply to conventional mass values.
5.3 Surface Area— For For classes 000, 00, 0, 1, 2, 3 and 4 the surface area is not to exceed twice the area of a cylinder of equal height and diameter for weights 1 g and above. Sheet metal weights or wire weights may be used below 1 g. For Classes 5, 6 and 7 the total surface areas should be minimized to the extent possible.
NOTE 2—Maximum 2—Maximum Permissible Permissible Error Errorss for weight weightss of denom denomination ination intermediate between those listed, the maximum permissible error shall be proportional to the values shown.
4.3 Fo 4.3 Forr cl class ass 00 000, 0, 00 an and d 0 we weig ight hts, s, wh whic ich h ar aree alw alway ayss accom acc ompa pani nied ed by cer certifi tificat cates es giv giving ing th thee mas masss va value luess an and d uncertainties, the deviation from the nominal value, mc – m0, shall be taken into account by the user.
5.4 Material: Classs 00 000, 0, 00 00,, 0, 1, 2, 3, 4, an and d 5 Wei eigh ghts ts— — The 5.4.1 Clas The hard ha rdne ness ss of th this is ma mate teria riall an and d its re resis sistan tance ce to we wear ar an and d corrosion shall be similar to or better than that of austenitic stainless stainle ss steel. 5.4.2 Classes 6 and 7— Cylindrical Cylindrical class 6 and 7 weights below 5 kg and class 6 and 7 weights below 100 g shall be made of steel or a material whose hardness and resistance to corrosion is similar or better than that of steel. Other cylindrical class 6 and 7 weights of 5 kg or greater shall be made of grey gre y cas castt iro iron n or of ano anothe therr mat materia eriall who whose se bri brittle ttlenes nesss and resistance resista nce to corro corrosion sion is similar or better than that of grey cast
5. Physical Characteristi Characteristics cs 5.1 Construction: 5.1.1 Type— Weights Weights are divided into two types based upon the design: 5.1.1.1 Type I— These These weights are of one-piece construction and an d co cont ntai ain n no ad adde ded d ad adju justi sting ng ma mater teria ial. l. Th They ey mu must st be specifie spe cified d whe when n weig weights hts are to be use used d as stan standar dards ds for the calibration of weights of Classes 000, 00, 0, 1, 2 and 3, and where maximum stability is required. A precise measurement of density can only be made for one-piece weights. 5.1.1.2 Type II— Weights Weights of this type can be of any appropria pr iate te de desi sign gn su such ch as sc scre rew w kn knob ob,, ri ring ng,, or se seal aled ed pl plug ug.. Adjusting material can be used as long as it is of a material at least as stable as the base material and is contained in such a way that it will not become separated from the weight. 5.1. 5. 1.2 2 Class Class 00 000, 0, 00 an and d 0 sh shal alll be Typ ypee I, on onee pi piec ecee construction. Weights with nominal values less than 1 g shall havee uni hav unique que sha shapes pes to dif differ ferent entiate iate the wei weight ghtss fro from m one
TABLE 2 Shape of Weights 1 g or Less
7
Nominal Values
P o l y go na l S he et s
Wires
5, 50, 500 mg 3, 30, 300 mg 2, 20, 200 mg 1, 1 0, 1 00 , 1 0 00 m g
P e nt ag o n Circle Square Triangle
P e nt ag on Circle Square Triangle
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE 4 Maximum Magnetic Susceptibility,
iron. The surface of the weights may be treated with a suitable coating coa ting in ord order er to imp improv rovee the their ir cor corros rosion ion res resist istanc ance. e. Thi Thiss coating shall withstand shocks and outdoor weather conditions. 5.5 Magnetism— Weights shall not exceed maximu maximum m permissible magnetic properties as listed in Tables in Tables 3 and 4 for 4 for any portion of the weight. If the values of all local measurements of magnetization magnet ization and susceptibility susceptibility are less than these limits, then it may be assumed that the uncertainty components due to the magnetism magnet ism of the weight are neglig negligible. ible. The maximum permanentt mag nen magnet netizat ization ion and mag magnet netic ic sus suscep ceptib tibilit ilities ies giv given en in Tables 3 and 4 are such that, at magnetic fields and magnetic field gradients possibly present on balance pans, they produce a change of the conventional mass of less than 1/10 of the maximum permissible error of the test weight.
χ
Weight Class
000, 00 and 0
1
2 an d 3
4 a nd 5
6 and 7
m # 1 g
0 .2 5
0 .9
10
2g
0 .0 6
0 .1 8
0 .7
Not applicable 4
0 .0 2
0 .0 7
0 .2
0. 8
Not applicable Not applicable Not applicable
# m 10 g 20 g # m #
Type I Weig eights hts— — Wei 5.8.1 Type eigh ghts ts sh shal alll be ad adju just sted ed by abrasio abr asion, n, gri grindi nding ng or any app approp ropria riate te meth method. od. The sur surface face requirement requi rementss shall be met at the end of the adjustm adjustment ent process. 5.8.2 Type II Weights— Weights Weights with adjusting cavities shall be adjusted with the same material from which they are made, or wi with th mat mater erial ialss th that at ar aree at le leas astt as sta stabl blee an and d of si simil milar ar density as the base material. For weights which have sealing caps, the cap may be made of aluminum. The back-up spacer shou sh ould ld be of a si simil milar ar ma mater terial ial as th thee we weig ight ht.. Ad Adju just stin ing g materia mate riall and bac back-u k-up p dis discc mus mustt mee meett the mag magnet netic ic req requir uireements specified for the accuracy class of the weight.
NOTE 3—Magneti 3—Magneticc susce susceptibil ptibility ity may be tested in accord accordance ance with OIML R 111-1, Annex B. Cast iron cannot have a susceptibility specification of any real value.
5.6 Density— Because Because of the effect of the buoyant force of air on a weight, precision measurements of mass require that the volume of the weight be known, as well as the density of thee air in wh th which ich it is be bein ing g mea measu sure red, d, so th that at ap appr prop opri riate ate corrections can be made. For weights of higher precision, the range of density is limited to values at or near the density of well-established standards, such as are used by primary calibration laboratories. For Class 000 and 00 the manufacturer shall provide a measured value for the density of the weights. As lower precision of measurement is required, so the range of density is broadened. See Table 5. 5. 5.6.1 5.6 .1 The dete determi rminat nation ion of the min minimu imum m and max maximu imum m density limits for nominal values not listed in Table 5 shall 5 shall be converted to metric values and the limits of the metric value next ne xt gr grea eater ter th than an th thee co conv nver erte ted d va valu luee us used ed.. (E (Exa xamp mple: le: 1 apothecary ounce class 4 is equal to 31.1034768 g, therefore the density limits are equal to values listed in Table in Table 5 for 5 for 50 g.)
5.9 Marking: 5.9. 5. 9.1 1 Class Class 00 000, 0, 00 an and d 0 we weig ight htss sh shal alll no nott be bear ar an any y indication of nominal value and shall not be marked unless used to distinguish from another class 000, 00 or 0 weight, provided that the surface quality and stability of the weights are not affected by the markings or by the process used to mark it. Numeri rica call Val alue ue fo forr Cla Class sses es 1, 2, 3, 4, 5, 6 an and d 5.9.2 Nume T he no nomi mina nall va valu luee of eac each h we weig ight ht sh shall all ap appe pear ar on th thee 7— The surfac sur facee of each weight. weight. Onl Only y the numerical numerical portion portion of the weight value needs to be on the surface of weights. Weights made of wire or too small to be marked shall not be marked but should be identifiable by their shape or number of bends. 5.9.3 Units of Weight— Weights Weights 100 g and greater may be marked with the unit name or abbreviation. In the case of sets of non-metric weights, at least the largest weight of a particular set should be marked with the unit name or abbreviation. In any case the unit shall not be included where such marking would be illegible. 5.9.4 Abbreviations— The T he ac accep cepted ted ab abbr brev evia iatio tion n ma may y be used in marking. Abbreviations are shown in Appendix X2. X2. Peri Pe riod odss sh shal alll no nott be us used ed wi with th ab abbr brev eviat iatio ions ns in ma mark rkin ing g weights. 5.9.5 Multiple Weights— Mult M ultip iple le we weig ight htss of th thee sa same me nominal value included in a set of weights shall have distinguishing marks. 5.9.6 Depth of Markings— Markings Markings shall be clear, shallow, relatively broad, and free of burrs and sharp angles. Markings shall not perforate or crack sheet metal weights. 5.9.7 User Marking— It It is recommended for a user to clearly identify individual weights as it helps to link a weight to its calibration certificate or verification document. The acceptable maximum values for user markings are given in Table 7. 7.
NOTE 4—Materials used to make weights for special applications that do not fall wit within hin the den densit sity y lim limits its stated above, above, sho should uld have sta stated ted densities or density determinations performed.
5.7 Finish— The The surface of the weights (including the base and corners) shall be smooth, the edges shall be rounded, and the weights shall not be porous. 5.7. 5. 7.1 1 Th Thee su surf rface ace qu quali ality ty of a we weig ight ht sh shall all no nott ex exce ceed ed maximu max imum m val values ues of sur surfac facee rou roughn ghness ess,, Ra and R z through visual inspection using a hand held gage. See Table 6. 6. 5.7.2 For weights with recessed areas for easier handling, handling, the recessed area and handle should have a finish with surface roughness no greater than R z = 1 µm and R A = 0.2 µm. The outer diameter, top and bottom surface roughness must meet Table 6. 6. 5.8 Adjustment:
TABLE 3 Maximum Polarization, µ0M , (µT)
6. Order Ordering ing Information Information
Weight Class
000, 00 and 0
1
2 and 3
4 a nd 5
6 and 7
Maximum polarization, µ0M , (µT)
2 .5
8
25
80
Not applicable
6.1 Selectio Selection n of type and class depends upon the application application of the weights. For reference standards, stability and information about the values of the weights is more important than the closeness of the values to nominal. Weights to be used with 8
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE 5 Minimum and Maximum Limits for Density
ρmin, ρ max (10 3 kg m–3)
Nominal Value
Class of Weight
1 00 g 50 g 20 g 10 g 5g 2g 1g 500 m g 200 m g 100 m g 50 mg 20 mg
$
0 00
00 and 0
1
2 a nd 3
4 and 5
7. 96 7 – 8. 03 3 7 .9 6 0 – 8 .0 4 7 .9 0 0 – 8 .0 9 7 .8 7 – 8 .1 4 7 .8 7 – 8 .1 3 7 .6 2 – 8 .4 2 7 .2 8 – 8 .9 0 7 . 5 0 – 8 .6 0 6 . 7 – 9 .6 6 .0 – 1 2 $ 4.8 $ 2.5
7 . 93 4 – 8. 06 7 7 .9 2 – 8 .0 8 7 .8 4 – 8 .1 7 7 .7 4 – 8 . 2 8 7 . 6 2 – 8 .4 2 7 . 2 7 – 8 .8 9 6 .9 – 9 .6 6 .3 – 1 0 . 9 5 . 3 – 1 6 .0 $ 4.4 $ 3.4 $ 2.3
7 .8 1 – 8 . 2 1 7 .7 4 – 8 .2 8 7 .5 0 – 8 .5 7 7 .2 7 – 8 .8 9 6 .9 – 9 . 6 6 .0 – 1 2 .0 5 .3 – 1 6 .0 $ 4.4 $ 3.0
7 . 3 9 – 8 .7 3 7 .2 7 – 8 .8 9 6 .6 – 1 0 .1 6 . 0 – 1 2 .0 5 .3 – 1 6 . 0 $ 4.0 $ 3.0 $ 2.2
6 .4 – 1 0 .7 6 .0 – 1 2 .0 4 . 8 – 2 4 .0 $ 4.0 $ 3.0 $ 2.0
TABLE 6 Maximum Values of Surface Roughness Classes 000, 00, 0
Classes 1, 2
Classes 3, 4
Class 5
Classes 6, 7
0. 1 0 .5
0 .2 1
0. 4 2
1 5
25 1 00
R A (µm) R Z (µm)
000 – 7 000, 00, 0 1 2–7 2–7 2-3 4–7
Nominal Value
Height of Lettering
Maximum Number of Signs, Numerals, or Letter Letters s
<1g 1g $ 1 g 1 g t o 10 0 g 2 00 g t o 10 k g $ 20 kg $ 20 kg
1 mm 2 mm 3 mm 3 mm 5 mm 7 mm 12 mm
2 3 5 5 5 5 5
$
$ $ $ $
4.4 4.0 2.6 2.0
soft material, they shall be smooth and polished and the edges on which the weight may be lifted shall be well rounded. 6.3.4 If forceps are used for lifting small weights, weights, stainless steel forceps with nonmetallic tips may be used, where the tips that th at co come me in co cont ntact act wi with th th thee we weig ight htss ar aree co cove vere red d wi with th a material softer than the surface of the weight, such as plastic or chamois skin from which the grease has been removed. The forceps may also be made of a material softer than the weights, such as close-grained wood or plastics not affected by alcohol. When the parts of the forceps which come in contact with the weights are not covered by a soft material, they shall be smooth and polished and the edges on which the weight may be lifted shall be well rounded.
TABLE 7 Maximu Maximum m Numbe Numberr of User Markin Markings gs Class
6 a nd 7
6.4 Cases: 6.4. 6. 4.1 1 Cla Class sses es 00 000, 0, 00 00,, 0, 1, 2, 3, an and d 4 we weig ight hts, s, wh when en supplied in sets, may be supplied with one or more cases or shall meet customer specifications for cases. The case shall be designed so that as long as the lid remains closed, the weights shall be held secure, and when possible the pocket depth shall be such that the shoulder of the weight does not extend above the edge of the pocket. The hinges and locks shall be adequate to hold the lid closed with any reasonable handling. There shall be no discoloration of weights due to the lining of the case, such as might result from long storage in a warm or damp location. This condition does not apply to weights not designed to be handled manually. 6.4.2 Pockets— A separate pocket shall be supplied for each weight and for each forceps and lifter, except that extremely largee lifters may not requi larg require re pockets. All pockets shall be large enough so that no appreciable friction shall be encountered in inserting or removing weights. If the cover is not lined, the individual holes in the cover shall be smooth or lined. Pockets for weights 1 g or equivalent or larger shall be constructed of a sm smoo ooth th no nona nabr bras asiv ivee ma mater teria ial, l, or lin lined ed wi with th a sm smoo ooth th,, nonabrasive material.
balancess of low pre balance precisi cision on do not require require sma small ll max maximu imum m permissible errors, nor need the choice of materials be limited to those of high stability. Appendix stability. Appendix X1 should X1 should serve as a guide in selecting weights for specific applications. 6.2 Class— Maximu Maximum m per permis missib sible le err errors ors for Clas Classes ses 000 throug thro ugh h 7 ar aree sh show own n in Tabl Tablee 1. Low Lower er num number berss ind indica icate te smaller maximum permis permissible sible error errors. s. 6.3 Lifters: 6.3.1 Classes 000, 000, 00, 0, 1, 2, 3, and 4 shall be supplied supplied with lifters lift ers whe when n sets of wei weight ghtss are ord ordere ered. d. Ind Indivi ividua duall wei weight ghtss shall be supplied with lifters when specified by the purchaser. Lifters or forceps shall securely hold the weights for which they are des design igned. ed. Addition Additional al pre pressu ssure re sha shall ll not cau cause se the droppi dro pping ng of smal smalll wei weight ghtss or the for forcef ceful ul ejec ejection tion of lar large ge weights. 6.3.2 For weights weights 500 g or larger, larger, the parts of the lifter that come co me in co cont ntac actt wi with th th thee we weig ight htss sh shal alll be co cove vere red d wi with th a non-magnetic material softer than the surface of the weight, such as plastic or chamois skin from which the grease has been removed. 6.3.3 6.3 .3 For smaller smaller weights, weights, the lift lifters ers may be of the same design where practical or may be of a non-magnetic material softer than the weights, such as close-grained wood or plastics not affected by alcohol. When the parts of the lifters or forceps which come in contact with the weights are not covered by a
6.5 Denominations— The The customer’s purchase order or contract shall define the contents of the weight set. 6.6 Density Identification— Weights Weights that are to be calibrated shall carry identification identification of the density of the various materials of wh which ich th thee we weig ight htss ar aree ma manu nufa factu cture red. d. Id Iden entifi tificat catio ion n of density shall be displayed on the certificate, or on the cover or interior of the box. 9
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 6.7 Special Requirements— If I f a cu cust stom omer er ha hass sp speci ecific fic re re-quirements that deviate from this standard (that is, material, shape, sha pe, max maximu imum m per permis missib sible le err errors ors,, etc. etc.)) the man manufa ufactu cturer rer may use this specification as a reference, not a requirement, to provide the customer with the weights that they need.
uncertainties). Statements of compliance by calibration laboratories during subsequent calibrations must meet the requirements of ISO/IEC 17025, 5.10.4.2 and indicate on the calibration report which sections have or have not been assessed. 8.2 Cleaning Weights: 8.2.1 It is impor important tant to clean weigh weights ts before any measurements are made because the cleaning process may change the mass of the weight. Cleaning should not remove any significant amounts of weight material. Weights should be handled and stored in such a way that they stay contamination-free. Before calibration, dust and any foreign particles shall be removed. Care must be taken not to change the surface properties of the weight (i.e. by scratching the weight). 8.2.2 If a weigh weightt contains significant significant amounts of contamination that cannot be removed by the methods cited above, the weight or some part of it can be washed with clean alcohol, distilled water or other solvents. Weights with internal cavities should normally not be immersed in the solvent to avoid the possibility that the fluid will penetrate the opening. If there is a need to monitor the stability of a weight in use, the mass of the weight should, if possible, be determined before cleaning. 8.2.3 After weights weights are cleaned with solvents they shall be stabilized for the times given in Table 9. 9.
7. Cert Certifica ificates tes 7.1 Calibration— Labora Laborator tories ies iss issuin uing g cali calibra bratio tion n rep report ortss for weights and weight sets shall have evidence of metrological traceability to the International System of Units (SI). Calibration certificates shall be issued only by laboratories having a quality system complying with the requirements of ISO/IEC 1702 17 025, 5, wh whic ich h ha hass pr pref efer erab ably ly be been en ve veri rifie fied d by th thir ird d pa part rty y assessment (accreditation). Calibration Certific Certificates— ates— A cali 7.1.1 Calibration calibra bration tion cer certific tificate ate shall sh all st state ate,, as a min minimu imum: m: th thee co conv nven entio tiona nall ma mass ss of eac each h weight, mc, an indication of whether a weight has been adjusted prior to calibration, its expanded uncertainty, U , and the value of the coverage factor, k . 7.1.2 Class 000, 00, and 0 weights shall shall be accompanied by a calibration certificate. 7.1.3 The certificate for Class 000, 00, and 0 weights shall state, as a minimum, the values of conventional mass, m c, the expanded uncertainty, U , and the coverage factor, k , and the density or volume for each weight. In addition, the certificate shall state if the density or volume was measured or estimated.
8.3 Thermal Stabilization— Prior Prior to performing any calibration tests, the weights need to be acclimated to the ambient conditions of the laboratory. In particular, weights of classes 000, 00, 0, 1 and 2 should be close to the temperature in the weighing weigh ing area. The mandatory minimum times requi required red for temperature temper ature stabilization stabilization (depe (depending nding on weight size, weigh weightt class and on the difference between the initial temperature of the weights and the room temperature in the laboratory) are shown sho wn in Table Table 10 10.. As a pr prac actic tical al gu guid ideli eline ne,, a mi mini nimu mum m waiting time of 24 hours is required for temperature stabilization of the weight with the laboratory environment for weight classes 000, 00, 0, 1, and 2.
Calibration, initial verification from the manu manufactur facturer er 7.2 Calibration, and subsequent calibration: 7.2.1 Table 8 gives 8 gives the required tests for initial calibration from the manufacturer and subsequent calibration. The categories of weights that are subject to calibration or initial calibration tio n fr from om th thee ma manu nufa factu cture rerr sh shou ould ld als also o be su subj bjec ectt to re re-cali ca libr brat atio ion, n, ma maki king ng it po poss ssib ible le to ve veri rify fy th that at th they ey ha have ve maintained their metrological properties. Any weights found defective at the time of re-calibration shall be reviewed with the customer. 7.2.2 For subsequent subsequent calibration, calibration, as a minimum, the weights shall be visually inspected for design and surface conditions and the mass checked.
8.4 Environmental Conditions— The The calibration of weights shall be performed at stable ambient conditions at temperatures close to room temperature. Required conditions are given in Table 11. 11. 8.4.1 8.4 .1 For 000, 00, 0 and 1 cla class ss weights, weights, the tem temper peratu ature re shall be within 17 °C to 23.5 °C. The environmental conditions shall be within the specifications of the weighing instrument.
8. Test Procedures Procedures 8.1 Weight manufacturer manufacturerss must be able to prov provide ide evidence that all new weights comply with specifications in this standard (e.g., material, density, magnetism, surface finish, mass values,
TABLE 8 Requi Requirement rements s for Determining Determining Which Tests Shall Be Perfo Performed rmed for Initia Initiall Ver Verificati ification on from the Manuf Manufacture acturerr and Subsequent Calibration
Test
Density
Surface Roughness
ρ
Class
0 00 - 1
IV SC
=
2-4
5-7
Magnetic Susceptibility
χ
0 00 - 1
2-4
5-7
000 - 1
2-4
V V
V V
V V
=
=
5-7
Permanent Magnetism M 0 00 - 1 = *
2-4
5-7
= *
= *
Legend: IV SC V = * +
= = = = = =
Initial verification Initial verification from the manufa manufacturer cturer that is performed when the weight is first put into service. service. Subsequent or periodic calibration. Visual inspection only. Testing required. In case of doubt, permanent permanent magnetization magnetization of a weigh weightt can be tested during subsequent subsequent calibration. calibration. Applies Applie s only for class class 000 and 00.
10
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Conventional Mass 00 0 - 1 = =
2-4
5-7
= =
= =
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE 9 Stabilization Time after Cleaning Weight Class
00 0, 00 an d 0
1
2
3-7
After cleaning with alcohol After cleaning with distilled water
7 – 10 day s 4 – 6 d ay s
3 – 6 d ay s 2 – 3 da y s
1 – 2 day s 1 da y
1 h ou r 1 h ou r
TABLE 10 Thermal Stabilization in Hours
∆T*
Nominal Value
Class 000, 00 and 0
Class 1
Class 2
Class 3 – 7
± 20 °C
1 00 0 , 2 0 00 , 50 00 k g 1 00 , 2 00 , 5 00 k g 1 0 , 20 , 5 0 k g 1, 2 , 5 k g 1 0 0, 2 00 , 5 0 0 g 10 , 2 0 , 5 0 g < 10 g 1 0 00 , 20 0 0, 50 0 0 k g 1 00 , 2 00 , 5 00 k g 1 0 , 20 , 5 0 k g 1, 2 , 5 k g 1 0 0, 2 00 , 5 0 0 g 10 , 2 0 , 5 0 g < 10 g 1 0 00 , 20 0 0, 50 0 0 k g 1 00 , 2 00 , 5 00 k g 1 0 , 20 , 5 0 k g 1, 2 , 5 k g 1 0 0, 2 00 , 5 0 0 g < 100 g 1 00 0 , 2 00 0 , 5 0 00 k g 1 00 , 2 00 , 5 00 k g 1 0 , 20 , 5 0 k g 1, 2 , 5 k g 1 0 0, 2 00 , 5 0 0 g < 100 g
45 18 8 2 1 36 15 6 2 0. 5 27 12 5 2 11 7 3 1
70 27 12 5 2 1 40 18 8 4 1 0 .5 16 10 5 3 1 1 1 1 1 0. 5
79 33 12 6 3 1 1 1 2 4 3 2 1 0 .5 1 1 1 1 1 1 0 .5 0 .5 0 .5 0 .5 0 .5
5 4 3 2 1 1 0 .5 1 1 1 1 0 .5 0 .5 0. 5 0 .5 0 .5 0 .5 0. 5 0 .5 0 .5 0. 5 0 .5 0 .5 0 .5 0 .5
± 5 °C
± 2 °C
±0.5 °C
∆T* = Initial difference between weight temperature and laboratory temperature. TABLE 11 Required Ambient Conditions during Calibration Weight class 00 0 , 0 0 an d 0 1 2 3 4-7
Temperature change during calibration ± 0.3 ºC per hour with a maximum of ± 0.5 ºC per 12 hours ± 0.7 ºC per hour with a maximum of ± 1 ºC per 12 hours ± 1.5 ºC per hour with a maximum of ± 2 ºC per 12 hours ± 2 ºC per hour with a maximum of ± 3.5 ºC per 12 hours ± 3 ºC per hour with a maximum of ± 5 ºC per 12 hours
Weight class 00 0 , 0 0 an d 0 1 4-7
Range of relative humidity (hr) of the air 40 % to 60 % with a maximum of ± 5 % per 4 hours 40 % to 60 % with a maximum of ± 10 % per 4 hours 40 % to 60 % with a maximum of ± 15 % per 4 hours
8.4.2 If the air density 8.4.2 density deviates deviates from from 1.2 kg m –3 by more than 10 %, mass values shall be used in calculations and the conventional mass shall be calculated from the mass. Weighing Instrument— The 8.4.3 Weighing The metrol metrological ogical charac characteristeristics of the weighing weighing instrumen instrumentt use used d sha shall ll be kno known wn fro from m earlier measurements and its resolution, linearity, repeatability and eccentricity shall be such that the required uncertainty can be reached. 8.4.4 Reference Weights— The The reference weight shall generally be of a higher class of accuracy than the weight to be calibrated. In the calibration of weights of class 000, 00 and 0, the reference weight shall have similar or better metrological
characteristicss (magn characteristic (magnetic etic prope properties, rties, surfa surface ce rough roughness) ness) than the weight to be calibrated. 8.5 Weighing Design: 8.5.1 Scope— This This sect section ion des describ cribes es two meth methods ods for the determination of the conventional mass of weights in a weight set: (1) The direct comparison method; and (2) The subdivision/multiplication method, which applies only for a set of weights.
11
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 8.5.1.1 Three differen 8.5.1.1 differentt weighing cycles are described, described, all of which are form formss of substitution substitution weigh weighing ing intended for, but not limited to, single-pan balances. 8.5. 8. 5.1. 1.2 2 Pr Prio iorr to ma mass ss de deter termin minati ation on,, th thee de dens nsity ity of th thee weights shall be known with sufficient accuracy. In addition, the environmental conditions and the metrological characteristics of the weighing instruments used in the mass determination shall be known with sufficient sufficient accuracy. accuracy. Formu Formulae lae for the determination determi nation of the conventional conventional mass and its uncer uncertainty tainty are to be followed. 8.5.2 Direct Comparison— Usually Usually the test weight should be calibr cal ibrate ated d by co comp mpar aris ison on ag agai ains nstt on onee or mo more re re refe fere renc ncee weights weig hts.. In eac each h com compar pariso ison, n, the nominal nominal mas masss of the test weight weig ht and the ref referen erence ce weig weight ht sho should uld be equ equal. al. A che check ck standard can be used to monitor the measurement process.
this case the weighing cycle can be applied for each reference weight separately. The reference weights may then be compared against one another. Compari arison son of the tes testt weig weight ht with one re refer ferenc encee 8.5.5 Comp weigh wei ghtt (r (rec ecom omme mend nded ed fo forr cl clas asss 00 000, 0, 00 00,, 0, 1, 2, 3, an and d 4 weights)— A variety of weighing cycles can be utilized. For two weights the following cycles, which are best known as ABBA and ABA, are possible. These cycles eliminate linear drift. Cycle ABBA (r1t1t2r2): Ir11, It11, It21, Ir21, ..., Ir1n, It1n, It2n, Ir2n
∆ I i 5 ~ I t 1 i 2 I r 1 i 2 I r 2 i 1 I r 2 i ! ⁄2
(2 )
where i = 1, … , n Cycle ABA (r1t1r2): Ir11, It11, Ir21, ..., Ir1n, It1n, Ir2n
∆ I i 5 I t 1 i 2 ~ I r 1 i 1 I r 2 i ! ⁄2
NOTE 5—Special problems may arise when calibrating class 000, 00 and 0 weights of less than one gram. This is partially due to a relatively large lar ge unc uncert ertain ainty ty of the ref refere erence nce wei weight ghtss in this range. Further Further,, the instability of the weighing instruments and a large surface area are factors that negatively influence the uncertainty of measurement. Therefore, the subdivision subdi vision method is stron strongly gly recom recommend mended ed for such weigh weights. ts.
(3 )
where i = 1, … , n 8.5.5. 8.5 .5.1 1 In cyc cycles les ABBA and ABA ABA,, n is th thee nu numb mber er of sequences. The i values are given in the order in which the weig we ight htss sh shou ould ld be pl place aced d on th thee we weig ighi hing ng pa pan. n. He Here re th thee subscr sub script iptss “r” and “t” den denote ote the ref refere erence nce weight and tes testt weightt respec weigh respectively tively.. ∆ I i is the ind indicat ication ion dif differ ferenc encee fro from m measurement sequence i. 8.5.5.2 8.5.5 .2 The time interval between between weighings weighings should be kept constant. 8.5.5.3 8.5.5 .3 If there is a need to determine the sensitivity sensitivity of the weighi wei ghing ng ins instru trumen mentt dur during ing the wei weighi ghing ng pro proces cess, s, the sequence ABBA can be modified to the form I r, I t, I t+ms, I r+ms, where “ms” is the sensitivity weight. 8.5. 8. 5.6 6 Compa Compari riso son n of se seve vera rall tes testt we weig ight htss of th thee sam samee nominal mass with one reference weight (cycle AB 1…BnA). If several test weights t( j) ( j = 1, ..., J ) with the same nominal mass are to be calibrated simultaneously the weighing cycle ABA can be modified into AB 1…BnA as follows: Cycle AB1…BnA: Ir11, It(1)1, It(2)1, ...,It( J )1 )1, Ir21, Ir12, It( J )2 )2, It( J –1)2 –1)2, ...,It(1)2, Ir22, … {Ir 1i–1, It(1)i–1, It(2)i–1, ..., It( J )i–1, Ir2i–1, Ir1i, It( J )i, It( J –1) –1)i ,..., It(1)i, Ir2i}
8.5.3 Subdivision— An A n en enti tire re set of we weig ight htss ca can n be cal caliibrated bra ted aga agains instt one or mor moree ref refere erence nce wei weight ghts. s. Thi Thiss meth method od requires several weighings within each decade in the set. In these weighings, different different combinations combinations of weigh weights ts of equal total nominal mass are compared. This method is mainly used to ca calib libra rate te se sets ts of cla class ss 00 000, 0, 00 an and d 0 we weig ight htss wh when en th thee highes hig hestt acc accura uracy cy is req requir uired. ed. If wit with h this method, method, onl only y one reference weight is used, the number of weighing equations shall be larger than the number of unknown weights and an appropriate adjustment calculation shall be performed in order to avoid propagating errors. If more than one reference weight is used, the number of equations may be equal to the number of unknown weights. In this case, no adjustment calculation is necessary. The advantage of such methods lies in the fact that they include a certain redundancy that offers greater confidence in the results. However, However, these methods, particularly particularly the adjus adjusttment calculation, require more advanced mathematics. 8.5.4 Weighing Cycles— Accepted Accepted procedures for three different weighing cycles for a single comparison weighing are described below.
∆ I i ( j ) 5 I t ( j ) i 2 ~ I r 1 i 1 I r 2 i ! ⁄2
(4 )
where i = 1, … , n 8.5.6.1 8.5.6 .1 If the drift in the weigh weighing ing indication indication is neglig negligible, ible, i.e., less than or equal to one third of the required uncertainty, it is not necessary to invert the order of the test weights in AB1…BnA wh when en re repe peat atin ing g th thee seq seque uenc nce. e. Th Thee nu numb mber er of weights shall normally not be more than 5 ( J ≤ ≤ 5). Numberr of weighin weighing g cycles— The 8.5.7 Numbe The number of weighing cycles, n , shall be based on the required uncertainty and on the repeata rep eatabil bility ity and rep reprod roduci ucibili bility ty of the mea measur sureme ements nts,, see Table 12. 12.
NOTE 6—Ot 6—Other her procedure proceduress and weighing weighing cycles may be use used. d. If in particular, weighing cycles are used that are not independent from each other, such as A1 B 2 A2, A 2 B 2 A3, ..., the uncertainty has to be evaluated by considering covariance terms and the formula given in Section 9 Section 9 must must be modified correspondingly.
8.5.4.1 In the weighing cycles, 8.5.4.1 cycles, “A” represents weighing weighing the reference weight and “B” represents weighing the test weight. The cycles ABBA and ABA are normally used when calibrating class 000, 00, 0, 1, 2 and 3 weights. 8.5.4.2 8.5.4 .2 The cycle AB1...BnA is often used when calibrating class 4, 5, 6 and 7 weights, but is generally not recommended for class 000, 00, 0, 1, 2, and 3 weights. If, however, a mass comparator with an automatic weight exchange mechanism is used and if the system is installed in a protecting housing, this cycle can also be accepted for class 000, 00, 0, 1, 2, 3, and 4 weights calibrations. 8.5.4.3 8.5.4 .3 Only cycles ABBA and ABA are are usefu usefull in subdivision weighing. weighing. More than one refere reference nce weight can be used. In
TABLE 12 Required Minimum Number of Weighing Cycles
12
Class
0 00 , 0 0, 0
1
2 an d 3
4 an d 5
6 an d 7
Minimum number of ABBA Minimum number of ABA Minimum number of AB1{Bn A
3
2
1
1
1
5
3
2
1
1
5
3
2
1
1
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 8.6 Data Analysis: Average ge dif differ ferenc encee of con conven vention tional al mas mass–o s–one ne test 8.6.1 Avera weight— For For cycles ABBA and ABA, the conventional mass difference, ∆mc, bet betwee ween n the test wei weight ght and the referenc referencee weight of a cycle, i , is:
∆ m c 5 m ct 2 m cr
(5 )
∆ m ci 5 ∆ I i 1 m cr C i
(6 )
Conventiona onall mas masss of the tes testt weig weight— ht— The 8.6.4 Conventi The conv convenentiona tio nall ma mass ss of th thee te test st we weig ight ht ca can n be ca calcu lcula lated ted fr from om th thee formula: m ct 5 m cr 1 ∆ m c
¯
Sρ ρ D 1
2
t
1
NOTE 7—The uncertainty calculations are based on the current GUM: JCGM 100 and supplements. Additional guidance may be found in NIST Tech echnic nical al Not Notee 129 1297. 7. Unc Uncert ertain ainty ty cal calcul culatio ations ns are app applied lied for mas masss comparisons. The uncertainty is evaluated either by the Type A or by the Type B method of evaluation. Type A evaluation is based on a statistical analysis of a series of measurements whereas Type B evaluation is based on other knowledge.
(7 )
r
The average difference of conventional mass for n cycles is:
¯ ∆
mc 5
1 ni
9.1 Standard uncertainty of the weighing process, u w (Type A)— The The stan standar dard d unc uncert ertain ainty ty of the weig weighin hing g pro proces cess, s, uw (∆mc), is the standard deviation of the mass difference. For n cycles of measur measurements ements::
n
( ∆m 5
1
(8 )
ci
8.6.1.1 8.6.1 .1 If the density, density, ρt or ρr, of a weight is not known, but the material is known, the appropriate assumed density from Table 13 shall 13 shall be used. If it is only known that the density of a weight is within the allowed limits, then the value 8 000 kg m–3 shall be used. 8.6.1.2 8.6.1 .2 In cases where air buoy buoyancy ancy correction correction is estimat estimated ed to be negligible, i.e. if: | c i| #
1 U 3 mo
¯
1 J ∆ m cj J j 1
( 5
(9 )
¯
s ( ∆ m c) 5
s 2 ( ∆ m c) 5
P l a ti n u m Nickel silver Brass S t a i n l e s s s te e l Carbon steel Iron Cast iron (white) Cast iron (grey) Al um i num
21,400 kg m-3 8,600 kg m-3 8,400 kg m-3 7,950 kg m-3 7,700 kg m-3 7,800 kg m-3 7,700 kg m-3 7,100 kg m-3 2,700 kg m-3
(10)
150 170 170 140 200 200 400 600 130
kg kg kg kg kg kg kg kg kg
(13)
n 1 ( ∆ m ci 2 ∆ m c ) 2 n 2 1i 1
(
¯
(14)
with n–1 degrees of freedom. 9.1.3 If only a few measurements measurements are made, the estimate estimate of unrelia eliable ble.. A pooled estimate, estimate, obt obtain ained ed fro from m s(∆mc) can be unr earlier measurements made under similar conditions, should be used. If this is not possible, n should not be less than 5. 9.1.4 9.1 .4 In the case where where there are J series series of measurements (where J > > 1), the variance of ∆mc is calculated by pooling over the J series series so that: s 2 ( ∆ mc) 5
1 J 2 s ( ∆mc) J j 1 j
(
(15)
5
with J (n–1) degrees of freedom. NOTE 8—The 8—The subsc subscript ript “ j” is ap appe pend nded ed to s j2(∆mc) to dif different ferentiate iate between the standard deviations for each series.
Uncertainty (k = = 2) ± ± ± ± ± ± ± ± ±
2· =3
5
TABLE 13 List of Alloys Most Commonly Used for Weights Assumed Density
max( ∆ m ci ) 2 min( ∆ m ci )
from n ≥ 3 cycles of measurements. The standard deviation can also be calculated as described in 9.1.2.. 9.1.2 9.1.2 For weight weight classes 000, 00, 00, 0, 1, and 2, the variance of the mass difference, ∆ mc, of the weighing process, s 2(∆mc), is estimated estimate d from n cycles of measurements by:
8.6.3.1 8.6.3. 1 Sev Severa erall ser series ies of mea measur sureme ements nts are usu usually ally per per-formed only in calibration of class 000, 00, and 0 weights, when the reproducibility of weighings has to be investigated. Minimum requirements for the number of weighing cycles are in Table in Table 12. 12.
Alloy/Material
(12)
=n
where s(∆mci) is defined below for the various classes of weights. 9.1. 9. 1.1 1 Cla Class sses es 3, 4, 5, 6, an and d 7, cy cycl cles es ABBA, ABBA, ABA or AB1…BnA are often applied. For these classes of weights, if the standard deviation of mass difference difference measurements measurements is not known from historical data, it can be estimated as:
¯
mc 5
s ~ ∆ m ci !
u w ( ∆ m c) 5
the term m0C i can be omi omitted tted.. How Howeve ever, r, the unc uncert ertain ainty ty contribution of C may not be negligible (see below in 9.3.1 in 9.3.1). ). If C may only an averaged or single value of the air density is available, the buoyancy correction, m cr C , can be applied after averaging. 8.6.2 Average difference of conventional mass – Several test weights— If If sev severa erall tes testt wei weight ghtss are cali calibra brated ted acco accordi rding ng to weighing weighi ng cycle AB1…BnA, the ave averag ragee mas masss dif differ ferenc encee for weight j is obtained from Eq from Eq 8 by replacing ∆ I i with ∆ I i(j) in in Eq Eq 6. Average ge dif differ ferenc encee of con conven ventio tional nal mas masss – Sev Severa erall 8.6.3 Avera series of measurements— If If there are several ( J ) identical series of measurements with average values ∆ m cj and with approximately mate ly equ equal al sta standa ndard rd dev deviati iations ons the ave averag ragee val value ue of all measurements measur ements is:
¯ ∆
(11)
9. Uncertainty Calculations
where: C i 5 ( ρ ai 2 ρ o ) 3
m-3 m-3 m-3 m-3 m-3 m-3 m-3 m-3 m-3
9.2 Uncertainty of the reference weight, u(m cr ) (Type B)— The standard uncertainty, u(mcr ), of the mass of the reference weight should be calculated from the calibration certificate by dividing the quoted expanded uncertainty, U , by the coverage factor, k (usually k = 2), and should be combined with the uncertainty due to the instability of the mass of the reference weight, uinst(mcr). 13
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 u ( m cr ) 5
ΠS D U k
2
1 u inst ( m cr ) 2
classs 00 clas 000, 0, 00 00,, 0 an and d 1 th thee CI CIPM PM fo form rmul ulaa (2 (200 007) 7) or an approximation can be used for the calculation of air density. 9.3.6 The variance variance of the air density is:
(16)
The uncertainty due to instability of the reference weight, uinst(mcr), can be estimated from observed mass changes after the ref refere erence nce weig weight ht has bee been n cali calibra brated ted sev severa erall tim times. es. If previous calibration values are not available, the estimation of uncertainty has to be based on experience. 9.2.1 9.2 .1 If a com combin binatio ation n of referenc referencee wei weight ghtss is use used d for a masss co mas comp mpar ariso ison n an and d th their eir co cova vari rian ance cess ar aree no nott kn know own, n, a correlation coefficient of 1 can be assumed, refer to the current GUM: JCGM 100 and supplements. This will lead to linear summation summati on of uncer uncertainties tainties:: u ~ m cr ! 5
(
i
u ~ m cr i !
u 2 ( ρ a ) 5 u 2F 1
≠
F
G
1 [ m cr ( ρ a 2 ρ o ) ] 2
≠
(17)
0.12
=3
[kg m
2
3
]
] a u ] t t
5
ρ a
2
1
D
] ρa u ] hr hr
2
(20)
1
ρ
23 21 5 2 3.4·10 a K
≠
ρ a
ρ
22 5 2 10 a
where hr = = relative humidity, as a fraction. 9.3. 9. 3.7 7 The de dens nsity ity of th thee re refe fere renc ncee we weig ight ht,, ρr, and its uncertainty should be known from its calibration certificate. 9.3.8 For classes classes 0 – 4 weights, the density density,, ρt, is not always know kn own, n, so it mu must st be eit eithe herr me measu asure red, d, or tak taken en fr from om th thee manufacturer’s specifications/recommendations, or taken from Table 13. 13.
(18)
where ρ al is the air density during the (previous) calibration of the referenc referencee weig weight ht by use of a hig higher her order order ref refere erence nce weight. When using Eq using Eq 18 be 18 be sure to use the same value for the uncertainty of the density of the reference weight, u(ρr), that was used in the uncertainty uncertainty calculation of the previ previous ous calibration. A larger uncertainty cannot be arbitrarily chosen. 9.3.1 Even if the air buoyancy buoyancy correction is negligible, negligible, the uncert unc ertain ainty ty con contrib tributio ution n of the buo buoyan yancy cy ef effec fectt may not be negligible, and shall be taken into account (see Eq (see Eq 18) 18). 9.3. 9. 3.2 2 Fo Forr cla class sses es 5, 6, an and d 7, th thee un unce cert rtain ainty ty du duee to air buoyancy correction is typically negligible and can usually be omitted. 9.3.3 9.3 .3 For classes classes 2, 3 and 4, the densitie densitiess of the wei weight ghtss have to be known with sufficient accuracy (see Table 5). 5). 9.3.4 If the air density is not measured measured and the average air density for the site is used, then the uncertainty for the air density is to be estimated as: u ( ρ a) 5
1
ρ a 2 2 5 ρ ρ 10 a Pa
≠ hr
u 2 ( ρ t )
ρ 4t u 2 ( ρ r ) 1 m 2cr ( ρ a 2 ρ o ) [ ( ρ a 2 ρ o ) 2 2 ( ρ al 2 ρ o ) ] ρ 4t
2
≠
≠ t
2
D Sρ D S
u F = [uncertainty of the formula used] (for CIPM formula: u formula: u F = 10–4 ρa)
Uncertainty ty of the air buo buoyan yancy cy cor corre rectio ction, n, u b (Type 9.3 Uncertain B)— The The uncertain uncertainty ty of the air buo buoyan yancy cy cor correc rectio tion n can be calculated calculat ed from from Eq Eq 18. 18 .
~ ρ r 2 ρ t ! u ~ ρ a! ρ r ρ t
] ρa u ] p p
hr = 0.5 (50 %), a tempera9.3.6.1 9.3.6 .1 At relative humidity humidity of hr ture of 20 °C and a pressure of 101,325 Pa, the following numerical values apply approximately:
where u (mcri) is the standard uncertainty of reference weight i. This is an upper limit for the uncertainty.
u 2b 5 m cr
S
9.4 Uncertainty of the balance u ba (Type B): Uncerta tain inty ty du duee to th thee te test st of ba bala lanc nces es an and d ma mass ss 9.4.1 Uncer comparators— The The recommended approach to determine this compon com ponent ent is to tes testt the balances balances and mass com compar parato ators rs at reasonable time intervals and use the results from the test in the uncertainty calculations. When calibrating class 000, 00 and 0 weights, it is recommended to perform several test measurements at different times to ensure that there is enough information about the uncertainty at the time of the measurement. 9.4.2 Uncertainty due to the sensitivity of the balance— If If the balance is calibrated with a sensitivity weight (or weights) of mass ms, and of standard uncertainty u(ms), the uncertainty contribution due to sensitivity is: u 2s 5
¯ S
~ ∆m ! c
2
u 2 ( m s ) m 2s
1
u 2 ( ∆ I s
∆ I 2s
D
(21)
where: = the chan change ge in the the indica indicatio tion n of the the balanc balancee due to to ∆ I s the sensitivity weight, uncert ertain ainty ty of of ∆ u(∆ I s) = the unc ∆ I s, and = the averag averagee mass mass dif differen ference ce betwee between n the test weigh weightt ∆mc and the reference weight.
(19)
¯
A lower value of uncertainty may be used if supporting data can be provided. At sea level the density of air may be assumed to be 1.2 kg –3 m . 9.3.5 For class 000, 00, 00, 0 and 1 weight weights, s, the density of air shall sha ll be det determ ermine ined. d. Its unc uncert ertaint ainty y is esti estimate mated d fro from m the uncertainties for temperature, pressure and air humidity. For
If the sensitivity is not constant with time, temperature and load, its variation must be included in the uncertainty. 9.4.3 Uncertainty due to the display resolution of a digital balance— For For a digital balance with the scale interval, d , the uncertainty due to resolution is:
TABLE 14 Coverage factor, k , for different effective degrees of freedom, ν eff 95.45 % 99 % 99.73 %
νeff
1
2
3
4
5
6
8
10
20
`
k k k
1 3 .9 7 6 3 .6 6 2 3 5 .8
4 .5 3 9 .9 2 1 9 .2 1
3 .3 1 5 .8 4 9 .2 2
2 .8 7 4 .6 0 6 .6 2
2. 65 4. 03 5 .5 1
2 .5 2 3 .7 1 4 .9 0
2 .3 7 3 .3 6 4. 28
2. 28 3. 17 3 .9 6
2 .1 3 2 .8 5 3. 42
2 .0 0 0 2 .5 7 6 3 .0 0 0
14
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 u d 5
d ⁄2
=3
· =2
9.4.5 Uncertainty due to magnetism, u ma — If If a weight has a high magnetic susceptibility susceptibility and/or is magnet magnetized, ized, the magnetic ne tic in inter terac actio tion n ca can n of ofte ten n be re redu duce ced d by pl plac acin ing g a no nonnmagnetic spacer between the weight and the load receptor. If thee we th weig ight htss sa satis tisfy fy th thee re requ quir irem emen ents ts of th this is sta stand ndar ard, d, th thee uncertainty due to magnetism, uma, may be assum assumed ed to be zero. 9.4.6 Combined standard uncertainty of the balance, u ba — The uncertainty components components are added quadratically quadratically as follows:
(22)
The factor √2 comes from the two readings, one with the reference weight and one with the test weight. 9.4.4 Uncertainty due to eccentric loading— If If this contribution buti on is kn know own n to be si sign gnifi ifican cant, t, th thee ma magn gnit itud udee mu must st be estimated and if necessary the contribution must be included in the uncert uncertainty ainty budg budget. et.
2 u ba 5 =u 2s 1 u E 1 u 2ma 1 u 2d
9.4.4.1 Acceptable solution for the uncertainty due to eccentricity: d 1 u E 5
d 2
9.5 Expanded uncertainty, U(m ct )— The The combin combined ed stand standard ard uncertainty of the conventional mass of the test weight is given by:
· D (23)
2· =3
u c ( m ct ) 5
where: D = the differen difference ce between between maximum maximum and minimum minimum values values from the eccentricity test performed, d 1 = th thee es estim timat ated ed di dist stan ance ce be betw twee een n th thee cen center terss of th thee weights, weigh ts, and d 2 = the distance distance from from the center of of the load receptor receptor to to one of the corners. In mos mostt cas cases, es, the unc uncerta ertaint inty y con contrib tributio ution n uE is alre already ady covered by the uncertainty uw of the weighing process and may be neglec neglected. ted.
? ∆ I 2 ∆ I ? 1
2
2
=u ~ ∆ m ! 1 u 2
w
¯ c
2
( m cr ) 1 u 2b 1 u 2ba
(26)
If the buoy buoyancy ancy correction, correction, mcrC , is not applied, a corresponding spondi ng con contri tribut bution ion for buo buoyan yancy cy has to be add added ed to the combined uncertainty in addition to ub: u c ( m ct ) 5
=u ~ ∆ m ! 1 u 2
w
¯ c
2
( m cr ) 1 u 2b 1 ~ m cr C ! 2 1 u 2ba
(27)
The expanded uncertainty, U , of the conventional mass of the test weight is as follows: U ( m ct ) 5 k u c ( m ct )
(28)
9.5.1 Usuall Usually y the coverage factor, k = 2, should be used. Howeve How everr, if a poo pooled led sta standa ndard rd dev deviati iation on of the wei weighi ghing ng process is not known and the number of measurements cannot reasonably be increased up to 10 (as for very large weights and long weighing procedures), and the uncertainty, uw (∆ m c ), is the dominant component in the uncertainty analysis, i.e. uw ( then en th thee co cove vera rage ge fa fact ctor or,, k , sh shou ould ld be ∆ m c ) > uc(mt ) / 2, th calculated from the t-distribution assuming a 95.45 % confidence den ce lev level el and the ef effec fectiv tivee deg degrees rees of fre freedo edom, m, νeff (as calculated calcula ted from the Welch-S elch-Satterth atterthwaite waite form formula). ula). The cover cover-age factor, k , for different effective degrees of freedom, ν eff , is given giv en in Tabl Tablee 14 14.. If it ca can n be as assu sume med d th that at th thee ty typ pe B uncertainty estimates are conservative with infinite degrees of freedom, the formula has the form:
9.4.4. 9.4 .4.2 2 When usi using ng bal balanc ances es with an aut automa omatic tic weig weight ht exchange mechan exchange mechanism, ism, the indica indication tion dif differen ference, ce, ∆ I , between two wei weight ghtss may be dif differ ferent ent whe when n the pos positio itions ns are int intererchanged: ∆ I 1 ≠ ∆ I 2. This may be interpreted as an eccentric loading load ing err error or and the cor corres respon pondin ding g unc uncerta ertaint inty y sho should uld be estimated estim ated usin using g Eq Eq 24. This This unce uncertain rtainty ty con contribu tribution tion is applicable, if it is known from previous interchanging measurements with weights of the same nominal value. In cases when whe n the int interc ercha hang ngee is per perfo form rmed ed du durin ring g a cal calib ibrat ration ion procedure, the average of the two indication differences shall be taken as the weighing result and uE can be neglected. u E 5
(25)
¯
¯
(24)
NOTE 9— 9—Eq Eq 24 is 24 is based on the same mathematical background as Note 6 in OIML D 28.
v ef f 5 ( n 2 1) ·
APPENDIXES (Nonmandatory Information) X1. APPLICA APPLICATIONS TIONS TABLE X1.1 Applications
NOTE 1—Balance classification information can be found in NIST Handbook 44 or OIML R 76. Class
Type
A p p l i c at i o n
0, 00 , 0 00 0 0 1 1 1
I I I I II I o r II
Laboratory Reference Standards Reference standards used for calibrating Class 1 weights Reference standards used for calibrating Class 2 weights Reference standards used for calibrating Class 3 weights Calibration weights used with calibration Class I balances Built in weights for high quality analytical balances
15
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
u 4c ( m ct ) u 4w
~∆m !
¯ c
(29)
Download From http://bbs.infoe http://bbs.infoeach.com ach.com E617 − 13 TABLE TA BLE X1.1 Continued Class
Type
A p p l i c at i o n
1, 2 2 3 4 4, 5, 6 5, 6 7
I I I I I I I
Cali Ca libr brat atio ion n we weig ight hts s us used ed wi with th ca cali libr brat atio ion n Cl Clas ass s II ba bala lanc nces es,, la labo bora rato tory ry we weig ight hts s fo forr ro rout utin ine e an anal alyt ytic ical al wo work rk Standards used for calibrating Class 4 weights Standards used for calibrating Class 5 weights Standards used for calibrating Class 6 weights Cali Ca libr brat atio ion n we weig ight hts s us used ed wi with th Cl Clas ass s II III, I, II IIIL IL an and d II IIII II ba bala lanc nces es.. Di Dial al sc scal ales es,, tr trip ip ba bala lanc nces es an and d pl plat atfo form rm sc scal ales es Student laboratory use Roug Ro ugh h we weig ighi hing ng op oper erat atio ions ns in ph phys ysic ical al an and d ch chem emic ical al la labo bora rato tori ries es su such ch as fo forc rce e me meas asur urin ing g ap appa para ratu tus s
or II o r II o r II o r II or II o r II or II
X2. ABBREVIA ABBREVIATIONS TIONS OF TERMS TABLE X2.1 Abbreviations of Terms Name of Unit Carat Dram, apothecary Grain, Troy Gram Kilogram Milligram Ounce, apothecary (480 grains) Ounce, avoirdupois (437.5 grains) Ounce, troy (480 grains) Pennyweight Pound avoirdupois Scruple, apothecary
Accepted Abbreviation
Conversion Factor (g/unitt of measur (g/uni measure) e)
c dr ap gr g kg mg oz ap oz oz t dwt lb s ap
0 .2 g 3 .8 8 7 9 3 4 6 g 0 .0 6 4 7 9 8 9 1 g 1g 1 00 0 g 0 .0 0 1 g 3 1 .1 0 3 4 7 6 8 g 2 8 .3 4 9 5 2 3 1 2 5 g 3 1. 10 3 4 76 8 g 1 .5 5 5 1 7 3 8 4 g 4 5 3. 59 2 3 7 g 1 .2 9 5 9 7 8 2 g
ASTM International International takes no positi position on respecting the validi validity ty of any patent rights assert asserted ed in connec connection tion with any item mentio mentioned ned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible respon sible technical technical committee, which you may attend. If you feel that your comments have not receiv received ed a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the above address addr ess or at 610610-832832-9585 9585 (pho (phone), ne), 610610-832832-9555 9555 (fax (fax), ), or serv service@ ice@astm astm.org .org (e-m (e-mail) ail);; or thro through ugh the ASTM webs website ite (www.astm. (www .astm.org). org). Permission Permission rights to photocopy the standa standard rd may also be secure secured d from the ASTM website (www.astm.or (www.astm.org/ g/ COPYRIGHT/).
16
Download From http://bbs.infoe http://bbs.infoeach.com ach.com
