1、Designation:E129302(Reapproved 2019)Standard Specification forGlass Measuring Pipets1This standard is issued under the fixed designation E1293;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in pare
2、ntheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This specification covers requirements for glass measur-ing pipets of precision and general purpose grades,used inmeasuring volumes of liquids.1.2 This i
3、nternational standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)
4、Committee.2.Referenced Documents2.1 ASTM Standards:2E438 Specification for Glasses in Laboratory ApparatusE542 Practice for Calibration of Laboratory VolumetricApparatusE671 Specification for Maximum Permissible Thermal Re-sidual Stress in Annealed Glass Laboratory ApparatusE694 Specification for La
5、boratory Glass Volumetric Appa-ratusE920 Specification for Commercially Packaged LaboratoryApparatusE921 Specification for Export Packaged Laboratory Appa-ratusE1133 Practice for Performance Testing of Packaged Labo-ratory Apparatus for United States Government Procure-mentsE1157 Specification for S
6、ampling and Testing of ReusableLaboratory GlasswareE1273 Specification for Color Coding of Reusable Labora-tory Pipets3.Classification3.1 Style,Class,and CapacityPipets covered by thisspecification shall be of the following styles,classes,andcapacities:3.1.1 Style 1Standard taper tip.3.1.1.1 Class A
7、Each pipet of precision grade shall bemarked with the letter“A”to signify compliance with appli-cable construction and accuracy requirements in Table 1.Eachpipet may be marked with a permanent serial number at theoption of the manufacturer.3.1.1.2 Class BGeneral purpose pipets are of the samebasic d
8、esign as Class A pipets.Volumetric tolerances for ClassB pipets shall be within twice the specified range allowed forClass A pipets.These pipets need not be marked with theirclass designation or serial number.See Table 1 for tolerancesand dimensional requirements.3.1.2 Style 2Long taper tip(Class B
9、only).3.1.3 Capacities,(mL)0.1,0.2,0.5,1,2,5,10,25,and 50.4.Design4.1 ShapeThe pipets shall be straight and of one-piececonstruction.Any cross section of a pipet taken in a planeperpendicular to the longitudinal axis shall be circular.4.2 Delivery TipsDelivery tips of Style 1 pipets shall bemade wit
10、h a gradual taper of 15 to 30 mm for capacities up to5 mL inclusive,and 20 to 40 mm for 10 to 50 mL capacitypipets.Style 2 pipets shall have a taper at a distance of 50 to65 mm from the tip end.The end of the tip shall be perpen-dicular to the longitudinal axis of the pipet.A sudden constric-tion at
11、 the orifice shall not be acceptable.The outside edge ofthe tip shall be beveled slightly at the end,and the bevel shallbe ground or firepolished.4.3 Zero Graduation Line Position The distance from thetop end to the top graduation of all pipets(except for 0.5 mLpipets)shall be not less than 90 mm;fo
12、r 0.5 mL pipets thisdistance shall be not less than 80 mm.4.4 Dimensions and Outflow TimesThe limiting dimen-sions and outflow times are shown in Table 1.Outflow timesshall be determined on unplugged pipets using distilled waterat 256 5 C and by means of a stopwatch.Outflow time shallbe determined b
13、y the unrestricted outflow of the water from thezero mark to base mark and until the water has ceased to flow.1This specification is under the jurisdiction of ASTM Committee E41 onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onLaboratory Ware and Supplies.Current edit
14、ion approved Jan.1,2019.Published February 2019.Originallyapproved in 1989.Last previous edition approved in 2012 as E1293 02(2012).DOI:10.1520/E1293-02R19.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMSta
15、ndards 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 StatesThis international standard was developed in accordance with internationally recognized principles on
16、standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 4.5 MarkingsAll markings shall be permanent and leg-ible.4.5.1 Graduation MarkingsGraduation lines shall not ex-ceed 0.4 mm in thickness and shall be in a plane perpendicularto the vertical axis of the pipet.The lines and other markingsshall be applied by one of the following methods:e
