1、Designation: A 126 04Standard Specification forGray Iron Castings for Valves, Flanges, and Pipe Fittings1This standard is issued under the fixed designation A 126; 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.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers three classes of
3、gray iron forcastings intended for use as valve pressure retaining parts, pipefittings, and flanges.1.2 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.NOTE 1The text of this standard references notes and footnotes whic
4、hprovide explanatory material. These notes and footnotes (excluding thosein tables and figures) shall not be considered as requirements of thestandard.2. Referenced Documents2.1 ASTM Standards:2A 48 Specification for Gray Iron CastingsA 644 Terminology Relating to Iron CastingsE 8 Test Methods for T
5、ension Testing of Metallic Materials3. Terminology3.1 Definitions of many terms common to gray iron castingsare found in Terminology A 644.4. Classification4.1 Castings produced to this specification are classifiedbased upon the minimum tensile strength of the iron (see Table1).5. Ordering Informati
6、on5.1 Orders for material in this specification should includethe following information:5.1.1 ASTM designation and year date,5.1.2 Class of iron required,5.1.3 Quantity, and5.1.4 Certification, if required (see Section 17).6. Workmanship, Finish, and Appearance6.1 The castings shall be made in a wor
7、kmanlike mannerand the surface shall be free of adhering sand, scale, cracks,and hot tears as determined by visual examination.7. Chemical Requirements7.1 A chemical analysis shall be performed on each lot andshall conform to the following requirements for phosphorusand sulfur:Phosphorus, max, % 0.7
8、5Sulfur, max, % 0.157.2 The chemical analysis shall be performed on a sampleobtained during the pouring of the lot.8. Tensile Properties8.1 One tension test shall be performed on each lot and shallconform to the mechanical properties specified inTable 1.9. Cast Test Bars9.1 Separately cast 118 in. (
9、28.6 mm) diameter test barsshown in Fig. 1 shall be poured in sand molds from the samelot as the castings represented.NOTE 2The numbering on the test specimens shown in Fig. 1 and Fig.2 is intended simply to illustrate a method of designation. In the particularmethod shown12refers to December 8, B 1
10、 is the cupola number, and thenumeral 1 which follows shows the hour cast (1 p.m.).9.2 Test bars that are intended to represent castings whichare cooled in the mold to less than 900F (480C) beforeshakeout, shall be cooled in their molds to a temperature lessthan 900F, and then may be cooled in still
11、 air to roomtemperature.9.3 Test bars that are intended to represent castings whichare hotter than 900F when shaken out of their molds, shall be1This specification is under the jurisdiction of ASTM Committee A04 on IronCastings and is the direct responsibility of Subcommittee A04.01 on Gray and Whit
12、eIron Castings.Current edition approved May 1, 2004. Published May 2004. Originallyapproved in 1929. Last previous edition approved in 2001 as A 126 95 (2001).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of
13、ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.TABLE 1 Tensile RequirementsClass A Class B Class CTensile strength, min, ksi(MPa)21 (145) 31 (214) 41 (283)1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428
14、-2959, United States.cooled as described in 9.2 or (by agreement between themanufacturer and the purchaser) may be shaken out of theirmolds at approximately the same temperature as the castingsthey represent.10. Tension Test Apparatus10.1 Ball and socket specimen holders or spherical-seatedbearings
15、or other device which will ensure that the specimen,when under load, will be as nearly as possible in pure axialtension without transverse stress shall be used in making thetension test.NOTE 3Suitable socket specimens holders and spherical-seated bear-ing device are shown in Fig. 4 and described in
16、5.2.3 of Test Methods E 8.10.2 After reaching a stress of 15 000 psi (103 MPa), thespeed of the crosshead of the testing machine shall not exceed18 in. (3.2 mm)/min.11. Sampling11.1 A lot shall consist of one of the following:11.1.1 All the metal poured from a single heating in a batchtype melting f
17、urnace,11.1.2 All the metal from two or more batch type meltingfurnaces poured into a single ladle or single casting, or11.1.3 All the metal poured from a continuous meltingfurnace for a given period of time between changes in charge,processing conditions, or aim-for chemistry or 4 h, whicheveris th
18、e shorter period.Metric Equivalentsin. 1/81/41/23/47/811/8 1.2 1 9/32 1 1/213/423/413mm 3.2 6.4 12.7 19.0 22.2 28.6 30.5 32.5 38.1 44.4 69.8 1330NOTEThese dimensions are suggested as satisfactory for average conditions, but may be varied to best suit individual pouring.FIG. 1 Mold of Tension and Tra
19、nsverse Test SpecimensMetric Equivalentsin. mm in. mm11/8 28.6 3 3/4 95.213/4 44.4 5 5/8 142.917/8 47.6 7 1/2 290.5NOTEModification may be made to the grip-ends of the tension test specimen to allow alternative means of gripping as required by testing proceduresand equipment. Should alternative grip
20、-ends be disputed, the threaded grip-ends shall be used.FIG. 2 Tension Test SpecimenA12604211.1.3.1 The purchaser may agree to extend the 4-h timeperiod to8hifthemanufacturer can demonstrate sufficientprocess control to warrant such an extension.12. Test Specimens12.1 Tension test specimens shall ha
21、ve threaded ends andconform to the dimensions shown in Fig. 2. The cross-sectionalarea of the reduced section shall be 1 in.2(645 mm2) 65 %. Theactual cross-sectional area shall be used in calculating thetensile strength.13. Alternate Test Bars13.1 Alternate test bars poured in accordance with Speci
22、fi-cation A 48 to the equivalent classes shown in Table 2 may besubstituted for the Specification A 126 test bars. When thealternate bars are used, they shall be machined and tested inaccordance with Specification A 48 and shall meet the require-ments of Specification A 48.14. Inspection14.1 All tes
23、ts and inspections required by this specificationshall be performed by the manufacturer or other reliablesources whose services have been contracted for by themanufacturer. Complete records of all tests and inspectionsshall be maintained by the manufacturer and shall be availablefor review by the pu
24、rchaser.15. Rejection and Rehearing15.1 Castings which fail to conform to the requirementsspecified when inspected or tested by the purchaser or his agentmay be rejected. Rejection shall be reported to the manufac-turer or supplier promptly and in writing. In case of dissatis-faction with the test r
25、esults, the manufacturer or supplier maymake claim for a rehearing.16. Certification16.1 When requested by the purchaser, the manufacturershall furnish the certification stating that the material wasmanufactured, sampled, tested, and inspected in accordancewith Specification A 126, including the yea
26、r date. The certifi-cation shall also include the results of all tests performedincluding chemical analysis.16.2 A signature is not required on the certification. How-ever, the document shall clearly identify the organizationsubmitting the certification and the authorized agent of themanufacturer wh
27、o certified the test results. Notwithstandingthe absence of a signature, the organization submitting thecertification is responsible for its content.17. Keywords17.1 gray iron castings; pressure retaining partsASTM International takes no position respecting the validity of any patent rights asserted
28、 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 revision at any time by the
29、 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. Your comments will receive c
30、areful 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 copyrighted by ASTM Internati
31、onal, 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).TABLE 2 Equivalent Classes (Specification A 48)SpecificationA 126 ClassUnder 0.50 in.(12.7 mm)0.51 to 1.00 in.(13.0 to 25.4 mm)Over 1 in.(25.4 mm)A25A20B20CB333C444A126043
