1、Designation: E671 98 (Reapproved 2016)Standard Specification forMaximum Permissible Thermal Residual Stress in AnnealedGlass Laboratory Apparatus1This standard is issued under the fixed designation E671; the number immediately following the designation indicates the year oforiginal adoption or, in t
2、he case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers a limit for thermal residualstress in reusable annealed gla
3、ss laboratory apparatus asdetermined by prescribed photoelastic measurement proce-dures.1.2 In broad classification, the laboratory glassware itemscovered by this specification, but not limited to, are:beakers Imhoff conesbottles, aspirator impingersbottles, dropping jars, batterybottles, gas washin
4、g jars, bellbottles, infusion jars, chromatographybottles, milk test jars, cylindricalbottles, reagent joints, ball and socket or standard taperbottles, weighing manometersbulbs, absorption percolatorsbulbs, leveling pycnometersbulbs, sampling stopcocksburets tubes, centrifugecondensers tubes, chrom
5、atographycrystallizing dishes tubes, color comparison (turbidity)culture dishes tubes, combustion (ignition)custom apparatus tubes, connecting and adaptercylinders, graduated tubes, digestionand plain tubes, dryingdesiccators tubes, fermentationextraction tubes tubes, thistle (spray traps)flasks vap
6、or trapsfritted ware viscometersfunnels watch glassesgenerators, Kippgrinder, tissue1.3 This specification recognizes that photoelastic measure-ments are proportional to the difference of the principalstresses. The limit imposed represents a safety factor to covera situation in which one of the prin
7、cipal stresses may be largerthan the apparent stress.1.4 This specification applies only to annealed glasswarethat is intended for sale as such. It excludes glassware that hasbeen thermally tempered, ion-exchanged, or laminated withglass layers of differing expansion. The intent of this specifi-cati
8、on is to limit the residual stresses for safe consumer use inannealed glass, as it leaves the manufacturer.1.5 Stresses introduced by thermal expansion differenceswithin the glassware are covered by this specification. Gradedand glass-to-metal seals are excluded.2. Referenced Documents2.1 ASTM Stand
9、ards:2E1157 Specification for Sampling and Testing of ReusableLaboratory GlasswareE1273 Specification for Color Coding of Reusable Labora-tory PipetsF218 Test Method for Measuring Optical Retardation andAnalyzing Stress in Glass3. Stress Limit3.1 The stress as measured by the procedure in Section 4a
10、nd calculated by Eq 2 shall not exceed 5.2 MPa (750 psi),except for combustion, centrifuge, and chromatography tubes,for which a limit of 4.5 MPa (650 psi) applies. Ware exceedingthese limits shall be rejected or reannealed to meet thespecification.4. Measurement Procedure4.1 Using a Friedel (Senarm
11、ont) polarimeter as described inTest Method F218, place the glass article to be measured in theviewing field in air. Examine every part of the article with adefinable light path (glass dimension) by rotating the analyzerto compensate for local stress birefringence. Document thosezones showing the hi
12、gher values for the retardation or thick-ness ratios by recording analyzer angle, glass thickness (lightpath), and position in ware.4.2 In some orientations, such as sighting perpendicular tothe axis of a thin-walled cylinder, two glass paths must beincluded in the measurement. If by rotating the cy
13、linder, theretardation appears to be relatively constant, the measurementis straightforward and the two walls define the light path. If the1This specification is under the jurisdiction of ASTM Committee E41 onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onLaboratory W
14、are and Supplies.Current edition approved Sept. 1, 2016. Published September 2016. Originallyapproved in 1979. Last previous edition approved in 2010 as E671 98 (2010).DOI: 10.1520/E0671-98R16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at se
15、rviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1retardation is variable, the scheme shown in Fig. 1 is
16、 recom-mended. If an adjacent region is found with low or constantretardation, or both, measure this retardation at normal inci-dence. Then use the recommended (slant) path shown whichincludes one wall of the adjacent region and one wall of theregion in question. The retardation that applies in this
17、 case isthe slant path reading algebraically corrected by one half of thenormal incidence reading taken in the adjacent zone (Note 1).If an adjacent region meeting these criteria cannot be found,simply record the maximum retardation detected through bothwalls of the variable region at normal inciden
18、ce.NOTE 1If large angles (10) from normal are chosen or necessary,the increased path must be cosine corrected (see Fig. 1).4.3 Other systems of determining stress-optical retardationare acceptable provided that the technique selected meets thesensitivity of the Friedel polarimeter, which has a least
19、 count ofapproximately 3 nm (1 analyzer rotation).4.4 For batch or continuous processes, testing and reportingmay be done by statistical sampling.5. Calculation of Stress5.1 Retardation/PathThe retardation per unit path, R, asdetermined with the Friedel polarimeter is given by:R 5FAt(1)where:A = ang
20、ular rotation of analyzer, degree,R = retardation per unit path, nm/cm,F = conversion factor: 3.15 nm/degree for white light;/180 for monochromatic light where is the wave-length of peak intensity, nm, andt = light path (glass thickness) for the particular viewingdirection, cm.5.2 Stress Calculation
21、The stress is determined by thefollowing equation 5RK(2)where: = stress, MPa, andK = stress-optical constant of the glass (Note 2), nm/cm MPa.NOTE 2The appropriate value for the glass in question can be suppliedby the glass manufacturer.6. Report6.1 Report the following information:6.1.1 Identificat
22、ion of article, type of glass,6.1.2 Manufacturing source and date,6.1.3 System for optical retardation measurement,6.1.4 Sketch of article with key measurement points,6.1.5 Table of data, coding measuring points and givinganalyzer readings, light path, statistical analyses, specialconsiderations, su
23、ch as slant path corrections in cylinders, andcalculated stress,6.1.6 Stress-optical constant used, and6.1.7 Date of test and name of operator.7. Sampling and Testing7.1 For sampling and testing, refer to Specification E1157.8. Keywords8.1 annealed glass; residual; stressFIG. 1 Scheme for Measuring
24、Retardation in Cylinder with Circumferentially Variable RetardationE671 98 (2016)2ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the v
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27、ve not received a fair hearing you shouldmake 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 multipl
28、e copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 98 (2016)3
