1、Designation: E 124 94 (Reapproved 2005)Standard Specification forWeighing and Drying Apparatus for Microchemical Analysis1This standard is issued under the fixed designation E 124; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e year of last revision. 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 apparatus used for weighingand drying operations in microchemical laboratory prac
3、tice.1.2 The values stated in inch-pound units are to be regardedas the standard. The metric equivalents may be approximate.NOTE 1This specification was originally developed by the Committeeon MicrochemicalApparatus, Division ofAnalytical Chemistry,AmericanChemical Society.22. Referenced Documents2.
4、1 ASTM Standards:3E 671 Specification for Maximum Permissible Thermal Re-sidual Stress in Annealed Laboratory ApparatusE 920 Specification for Commercially Packaged LaboratoryApparatusE 921 Specification for Export Packaged Laboratory Appa-ratusE 1133 Practice for Performance Testing of Packaged Lab
5、o-ratory Apparatus United States Government ProcurementE 1157 Specification for Sampling and Testing LaboratoryGlassware3. Combustion Boats3.1 Combustion boats of three sizes shall conform to therequirements in Table 1 and Fig. 1, Fig. 2, and Fig. 3. Theseboats shall be made of platinum-rhodium allo
6、y containing3.5 % rhodium.4. Weighing Bottles4.1 Weighing bottles of seven capacities shall conform tothe requirements in Table 2 and Figs. 4-9, inclusive.5. Weighing Cup5.1 The weighing cup shall conform to the requirementsshown in Fig. 11, and shall be made of platinum-rhodium alloycontaining 3.5
7、% rhodium. The cup is designed to be used as asample container to fit into the weighing bottle shown in Fig.5, and is useful for weighing hygroscopic materials.6. Weighing Tubes6.1 Weighing tubes of three types shall conform to therequirements shown in Fig. 12, Fig. 13, and Fig. 14. Thesetubes shoul
8、d preferably be made of soda-lime glass.7. Spatulas7.1 Spatulas of four types, and preferably made of stainlesssteel, shall conform to the following requirements:7.1.1 TypeA(Fig. 15)This spatula is generally useful. Thetop can be used for crushing crystals and the bent blade forscraping containers.7
9、.1.2 Type B (Fig. 16)This spatula has a flat bent portionat one end and a V-shaped scoop at the other end. It isparticularly useful for weighing samples.7.1.3 TypeC(Fig. 17)This spatula is suitable for thelarger samples commonly encountered in semimicro and pre-parative work. It has a U-shaped scoop
10、 at one end and aV-shaped scoop at the other end. The spatula can be used to addshot or beads to tare flasks and for measuring and introducingsolid reagent into combustion tubes.7.1.4 TypeD(Fig. 18)This spatula is useful in manymicrochemical applications.8. Forceps8.1 Forceps of two types, made of n
11、ickel-plated steel, shallconform to the following requirements:8.1.1 Forceps with Platinum5 % Ruthenium Tips (Fig.19) The pin serves as a stop to prevent the forceps from beingdepressed to such an extent that the tips can open, allowing theheld object to drop. When pressed together, the tips makecon
12、tact for a distance of14 to12 in. (6.4 to 12.7 mm).NOTE 2Depending upon the intended use, other materials may besubstituted for the platinum alloy. Thec construction and over-all dimen-sions should be identical with those shown in Fig. 19.1This specification is under the jurisdiction of ASTM Committ
13、ee E41 onLaboratory Apparatus and is the direct responsibility of Subcommittee E41.01 onApparatus.Current edition approved May 1, 2005. Published May 2005. Originallyapproved in 1956. Last previous edition approved in 1999 as E 124 61 (1999).2See the “1949 Report on Recommended Specifications for Mi
14、crochemicalApparatus, Carbon-Hydrogen, Dumas Nitrogen, Sulfur and Halogen,” AnalyticalChemistry, Vol 21, December 1949, p. 1555; and the “1953 Report on Recom-mended Specifications for Microchemical Apparatus, Weighing and Drying,”Analytical Chemistry, Vol 26, July 1954, p. 1186.3For referenced ASTM
15、 standards, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohoc
16、ken, PA 19428-2959, United States.8.1.2 Forceps with Conical Tapered Holders (Fig. 20)These forceps shall be made of spring steel. They are useful forhandling weighing tubes, absorption tubes, filter tubes, etc.9. Tare Flasks9.1 Tare flasks of three types, made of soda-lime glass, shallconform to th
17、e requirements shown in Fig. 21, Fig. 22, and Fig.23. The serial numbers shall be etched on the flasks.10. Metal Cooling Block10.1 The metal cooling block shall conform to the require-ments shown in Fig. 24, and shall be made of a metal or alloywith a high heat conductivity. The surface should be hi
18、ghlyresistant to abrasion and corrosion.11. Metal Crucible Container with Glass Cover11.1 This assembly shall conform to the requirementsshown in Fig. 25, and shall consist of an aluminum body anda borosilicate-glass cover. It may be used in combination withthe metal cooling block, Fig. 24. The comb
19、ination, commonlytermed a “microdesiccator,” serves primarily as a container forcooling, storage, and safe transportation of microweighingequipment.12. Micro Glass Desiccator with Metal Insert12.1 The micro glass desiccator shall conform to the re-quirements shown in Fig. 26. It shall consist of a g
20、lassdesiccator with cover and an aluminum insert which shall holdsecurely the metal cooling block, Fig. 24. This combinationserves the same purpose as that described in Section 11, butpermits the additional use of drying agents of other chemicalsin the bottom container.13. Drying Apparatus13.1 The d
21、rying apparatus shall be of the Abderhalden typeand shall conform to the requirements shown in Fig. 27.NOTE 3The shape of the tube attached to the ball joint, in thedesiccator bulb, is intended to prevent desiccant from being carried overinto the sample when the vacuum is broken. A cap for the ball
22、joint andstopper for the standard taper 40/50 joint may be used to protect thedesiccant when the bulb is disconnected and stands alone. The upwardindentation in the vapor tube prevents cooling of the drying chamber bycold condensate.14. Maximum Permissible Thermal Residual Stress14.1 The stress in a
23、ll glass items described herein shallconform to Specification E 671.15. Sampling and Testing15.1 For glass items, refer to Specification E 1157.16. Packaging16.1 For packaging, select from Specification E 920 orE 921, or Practice E 1133.17. Keywords17.1 apparatus; microchemical; weighing and dryingT
24、ABLE 1 Combustion BoatsSize Figure UseApproximateWeight, gA 1 for samples of 1 to 5 mgA0.45B 2 for samples of 5 to 25 mgA0.7C 3 for samples over 25 mgA,B1.5AFor drying procedures, the Size A boat is used with the weighing bottle, Fig. 8.Sizes B and C can be used either with the metal weighing bottle
25、s, Figs. 9 and 10,respectively, or with the glass weighing bottles, pig-type, Figs. 6 and 7.BThe Size C boat is especially suitable for bulky materials and explosivesubstances, and for holding glass capillaries containing liquid samples.E 124 94 (2005)2TABLE 2 Weighing BottlesFigureApproximateCapaci
26、ty, mLApproximateWeight, gMaterial4A0.05 0.6 borosilicate glass5 0.75 2.5 soda-lime glass6B3 5.0 soda-lime glass7B,C3 5.7 soda-lime glass8D0.5 1.5 aluminum alloy9D1 4.5 aluminum alloy0D2 6 aluminum alloyAThis bottle is intended for introducing samples into containers of smalldiameters.BThe cap of th
27、e bottle shown in Fig. 5 may be used instead of the caps with rodhandle shown in Figs. 6 and 7.CThis bottle, Fig. 7, is used for extremely hygroscopic materials; only the smallcap is removed for vacuum drying, and it is replaced as soon as the vacuum isreleased. The bottle containing the combustion
28、boat with sample may be attachedto a combustion tube by means of a rubber adapter, and the boat pushed intoposition in the tube by passing a wire through the small joint.DThese bottles are designed for use in conjunction with the combustion boats,Figs. 1-3, as follows:Bottle Use with BoatFig. 8 Fig.
29、 1Fig. 9 Fig. 2Fig. 10 Fig. 3The combination is useful for weighing and drying extremely hygroscopicmaterial. Sample, boat, and bottle are weighed, and the combination, withoutremoving the cap, is placed in the drying apparatus (Fig. 27). During drying, vaporsescape through the capillary. After dryi
30、ng, the combination is reweighed.FIG. 1 Combustion Boat, Size AFIG. 2 Combustion Boat, Size BFIG. 3 Combustion Boat, Size CFIG. 4 Weighing BottleE 124 94 (2005)3FIG. 5 Weighing Bottle, Outside CapFIG. 6 Weighing Bottle, Pig-Type, with Outside CapsE 124 94 (2005)4FIG. 7 Weighing Bottle, Pig-Type, wit
31、h Two CapsFIG. 8 Weighing Bottle, Pig-Type, Metal, Size AFIG. 9 Weighing Bottle, Pig-Type, Metal, Size BE 124 94 (2005)5FIG. 10 Weighing Bottle, Pig-Type, Metal, Size CFIG. 11 Weighing CupFIG. 12 Weighing TubeFIG. 13 Weighing Tube with CapE 124 94 (2005)6FIG. 14 Weighing Tube with Vented CapFIG. 15
32、Spatula, Metal, Type AFIG. 16 Spatula, Metal, Type BFIG. 17 Spatula, Metal, Type CE 124 94 (2005)7FIG. 18 Spatula, Metal, Type DFIG. 19 Steel Forceps (Nickel Plated) with Platinum - 5 % Ruthenium TipsE 124 94 (2005)8FIG. 20 Steel Forceps (Nickel Plated) with Conical TaperedHoldersFIG. 21 Tar Flask,
33、Without Stopper, SmallFIG. 22 Tare Flask, Without Stopper, LargeE 124 94 (2005)9FIG. 23 Tare Flask with StopperFIG. 24 Metal Cooling BlockFIG. 25 Metal Crucible Container with Glass CoverE 124 94 (2005)10Metric Equivalentsin. 0.040183161471691634 2716mm. 11.0 3.2 4.8 6.4 11.1 14.3 19.1 61.9FIG. 26 G
34、lass Desiccator with Metal InsertFIG. 27 Modified Abderhalden Drying ApparatusE 124 94 (2005)11ASTM 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 determina
35、tion 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 revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or with
36、drawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that you
37、r 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 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 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 124 94 (2005)12
