ASTM E677-1994(2004) Standard Specification for Interchangeable Spherical Ground Joints《可互换的圆球形接头》.pdf

1、Designation: E 677 94 (Reapproved 2004)Standard Specification forInterchangeable Spherical Ground Joints1This standard is issued under the fixed designation E 677; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last re

2、vision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers standard dimensional require-ments for obtaining, within practical limits, interchangeabilityin sp

3、herical ground joints for ordinary laboratory and industrialapplications. It covers dimensional interchangeability of theground surfaces only and does not involve design characteris-tics of the item except where specified, nor does it involvephysical or chemical characteristics of the material used.

4、NOTE 1The dimensions pertaining to spherical ground joints weretaken from the Commercial Standard CS 2158 of the U.S. Department ofCommerce.NOTE 2Although glass is the most commonly used material forground joints, other materials may be used as specified. Spherical jointsconstructed from glass shall

5、 conform to Specifications E 438 and E 671.1.2 The following precautionary caveat pertains only to theTest Method portion, Section 4, of this specification. Thisstandard does not purport to address all of the safety concerns,if any, associated with its use. It is the responsibility of the userof thi

6、s standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.2. Referenced Documents2.1 ASTM Standards:2E 438 Specification for Glasses in Laboratory ApparatusE 671 Specification for Maximum Permissible ThermalResidual Stress

7、in Annealed Glass Laboratory ApparatusE 920 Specification for Commercially Packaged LaboratoryApparatusE 921 Specification for Export Packaged Laboratory Appa-ratusE 1133 Practice for Performance Testing of Packaged Labo-ratory Apparatus for United States Government Procure-mentsE 1157 Specification

8、 for Sampling and Testing ReusableLaboratory Glassware2.2 U.S. Department of Commerce Standard:CS-21 Interchangeable Taper-Ground Joints, Stopcocks,Stoppers, and Spherical-Ground Joints33. Requirements3.1 Socket MemberThe design of the socket member isshown in Fig. 1. The contour of the ground area

9、shall bespherical, with a radius of curvature equal to one half of thegaging ball diameter specified in Table 1 as a minimum. Thecontour of the shoulder shall be essentially spherical andconcentric with the ground area. When tested in accordancewith 4.2, socket members shall show a continuous circum

10、fer-ential line of contact with the gaging ball.3.2 Ball MemberThe design of the ball member is shownin Fig. 1. The contour of the ground area shall be spherical,with a radius of curvature equal to one half of the gaging balldiameter as specified in Table 1 as a maximum. The contour ofthe shoulder s

11、hall be essentially spherical, approximatelyconcentric with the ground area and with a slightly smallerradius to provide a short offset at or slightly beyond the line ofthe gaging diameter. Ball members shall meet the reducedpressure test (4.3) when assembled with a socket membercomplying with 3.1.3

12、3 Size DesignationThe size designation of joints shallbe the accepted nominal gaging diameter, plus the insidediameter of the joint within the ball member, both expressed inmillimetres and separated by a line. Therefore, the designation18/7 means that the nominal gaging diameter of the joint is 18m

13、m and the inside diameter of the joint is 7 mm.3.4 DimensionsThe size designations and essential di-mensions of joints are shown in Table 1. Only the sizes listedshall be considered standard.3.5 InterchangeabilityWhen assembled ball-and-socketmembers are paired at random and tested under reducedpres

14、sure, the leak rates shall not exceed those specified in 4.3.4. Test Methods4.1 Gaging the BallGaging balls shall have dimensionsand tolerances shown in Table 1.4.2 Gaging the SocketSockets shall be tested against agaging ball. The ball shall enter the socket and the line of1This specification is un

15、der the jurisdiction of ASTM Committee E41 onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onApparatus.Current edition approved May 1, 2004. Published May 2004. Originally approvedin 1980. Last previous edition approved in 1998 as E 677 94 (1998).2For referenced ASTM s

16、tandards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Discontinued 1979U.S. Department of Commerce, Washington, DC 20234.1Copyright ASTM

17、 International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.contact shall be continuous circumferentially. This line may beobtained with the use of a film of Prussian blue or stopcockgrease applied to the gaging ball.4.3 LeakageUse the leak test apparatus illu

18、strated in Fig.2, or one functionally similar to it, with the average differentialpressure during the test kept above 600 mm Hg. Conduct thetest as follows:4.3.1 Clean both joints to be tested with distilled water, andthen dry them with a clean paper towel. Next, wipe the groundzones with a clean ch

19、amois to remove any remaining particles.4.3.2 Tightly close the unground end of the joint to beconnected to the manometer system, using a rubber stoppercontaining a concentric hole (or rubber tubing, depending uponthe joint size under test) sized to fit snugly on the manometerconnection, and mount t

20、he joint on the connection in an uprightposition.4.3.3 Firmly plug the unground end of the other type of jointwith a solid rubber stopper.4.3.4 Carefully mate the ground surfaces of the jointswithout exerting any pressure on them.4.3.5 Gently apply a 225-g weight on the upper joint forseating pressu

21、re; then rotate the upper joint 90 and remove theweight.4.3.6 After ensuring that the stopcock to the vacuum pumpis in the closed position, turn on the pump, and adjust thestopcock to the pump so that the mercury in the manometerrises to a level such that the average differential pressure willremain

22、 above 600 mm Hg at the conclusion of the test.4.3.7 Allow air leakage to occur through the mated joints fora timed interval, and note the change in differential pressure.4.3.8 Repeat 4.3.4-4.3.7 once, ensuring in 4.3.5 that theupper joint is rotated 90 from its position in the first test.4.3.9 Calc

23、ulationCompute the leak rate in torrL/s orPaL/s as follows:Leak rate 5 DP!V!/T (1)where:DP = maximum change in differential pressure noted intest, mm Hg or Pa,V = total evacuated volume, including manometer tubing,connections, flask, and joints, L, andT = time of test, s.The leak rate shall not exce

24、ed the following values:Leak RateJoint Size torrL/s PaL/sFIG. 1 Diagram of Ball-and-Socket MembersTABLE 1 Spherical Ground JointsJoint SizeDesignationNominalGagingDiameter,mmDimensionD(approximate),mmGaging BallDiameter,mm7/1 7 1.0 7.144 6 0.00112/1 12 1.0 12.700 6 0.00312/1.5 12 1.5 12.700 6 0.0031

25、2/2 12 2.0 12.700 6 0.00312/3 12 3.0 12.700 6 0.00312/5 12 5.0 12.700 6 0.00318/7 18 7.0 19.050 6 0.00318/9 18 9.0 19.050 6 0.00328/12 28 12.0 28.575 6 0.00428/15 28 15.0 28.575 6 0.00435/20 35 20.0 34.925 6 0.00435/25 35 25.0 34.925 6 0.00440/25 40 25.0 41.275 6 0.00450/30 50 30.0 50.800 6 0.00465/

26、40 65 40.0 63.500 6 0.00575/50 75 50.0 76.200 6 0.006102/75 102 75.0 101.600 6 0.008NOTE 1Evacuated volume of manometer tubing, connections, andflask shall be 100 to 150 cm3. Joint volume shall be added for leak ratecalculation.NOTE 2Leak rate of apparatus shall not exceed 5 % of that of jointbeing

27、tested. Spherical joints constructed from glass shall conform toSpecifications E 438 and E 671.NOTE 3Dimensions are in millimetres and are approximate, exceptfor minimum diameters.FIG. 2 Schematic Representation of Leak Test ApparatusE 677 94 (2004)27/1 to 12/5 0.15 20.018/7 to 28/15 0.30 39.935/20

28、to 75/50 0.45 59.8102/75 0.60 79.85. Marking5.1 Interchangeable spherical ground joints conforming tothis specification shall be marked on both members with thesymbol SJ indicating spherical joint, the size designation, andthe trademark of manufacturer or distributor. This symbol isthe manufacturers

29、 assurance to purchasers that the itemidentified by the symbol is a standard interchangeable size andtype described and is manufactured within the tolerancespermitted by this specification. It shall not be used on joints norin advertising description of joints of any size or type otherthan those des

30、cribed in this standard.6. Sampling and Testing6.1 For sampling and testing refer to Specification E 1157.7. Packaging7.1 For packaging, select from Specifications E 920 orE 921 or Practice E 1133.8. Keywords8.1 ground; joints; sphericalASTM International takes no position respecting the validity of

31、 any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to

32、revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Y

33、our comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is co

34、pyrighted 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 aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).E 677 94 (2004)3