1、Designation: B 468 04Standard Specification forWelded UNS N08020, N08024, and N08026 Alloy Tubes1This standard is issued under the fixed designation B 468; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision.
2、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 specification2covers welded UNS N08020,N08024, and N08026 alloy boiler, heat exchanger, and con-denser tubes for general corros
3、ion-resisting and low- or high-temperature service.1.2 This specification covers tubes18 to 5 in. (3.18 to 127mm), inclusive, in outside diameter and 0.015 to 0.500 in. (0.38to 12.70 mm), inclusive, in wall thickness. Table 2 of Speci-fication B 751 lists the dimensional requirements of these sizes.
4、Tubes having other dimensions may be furnished providedsuch tubing complies with all other requirements of thisspecification.1.3 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.1.4 This standard does not purport to addr
5、ess all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to become familiarwith all hazards including those identified in the appropriateMaterial Safety Data Sheet for this product/material as pro-vided by the manufacturer, to establish app
6、ropriate safety andhealth practices, and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:3A 262 Practices for Detecting Susceptibility to Intergranu-lar Attack in Austenitic Stainless SteelsB 751 Specification for General Requirements for N
7、ickeland Nickel-Alloy Welded TubeB 899 Terminology Relating to Non-ferrous Metals andAlloys3. Terminology3.1 Definitions:3.1.1 Definitions for terms defined in Terminology B 899shall apply unless otherwise defined by the requirements of thisdocument.4. General Requirement4.1 Material furnished in ac
8、cordance with this specificationshall conform to the applicable requirements of the currentedition of Specification B 751 unless otherwise providedherein.5. Ordering Information5.1 It is the responsibility of the purchaser to specify allrequirements that are necessary for material ordered under this
9、specification. Examples of such requirements include, but arenot limited to, the following:5.1.1 Quantity (feet or number of lengths),5.1.2 UNS number,5.1.3 Size (outside diameter and minimum or average wallthickness),5.1.4 Length (random or specific),5.1.5 ASTM designation,5.1.6 Product Analysis St
10、ate if required,5.1.7 Certification State if a certification or a report of testresults is required,5.1.8 Purchaser InspectionState which tests or inspec-tions are to be witnessed, if any, and5.1.9 Supplementary requirements, if any.6. Materials and Manufacture6.1 The tubing shall be made from flat-
11、rolled stock by anautomatic welding process with no addition of filler metal.Subsequent to welding and prior to final heat treatment, thematerial shall be cold-worked in either the weld metal only, orin both the weld and base metal.6.2 Heat Treatment Tubing of UNS N08020 alloy shall befurnished in t
12、he stabilized-annealed condition. Tubing of UNSN08024 alloy shall be furnished in the annealed condition.Tubing of UNS N08026 alloy shall be furnished in thesolution-annealed condition.1This specification is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and Alloys and is the direc
13、t responsibility of SubcommitteeB02.07 on Refined Nickel and Cobalt and Their Alloys.Current edition approved Feb. 1, 2004. Published February 2004. Originallyapproved in 1968. Last previous edition approved in 1999 as B 468 99.2For ASME Boiler and Pressure Vessel Code applications, see related Spec
14、ifi-cation SB-468 in Section II of that code.3For referenced ASTM 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
15、International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1The recommended annealing temperatures are 1800 to1850F (982 to 1010C) for UNS N08020, 1925 to 1975F (1052 to1079C) for UNS N08024, and 2050 to 2200F (1121 to 1204C) for UNSN08026.7. Chemical Com
16、position7.1 The material shall conform to the composition limitsspecified in Table 1. One test is required for each lot as definedin Specification B 751.7.2 If a product analysis is performed, it shall meet thechemistry limits prescribed in Table 1, subject to the analysistolerances specified in Tab
17、le 6 of Specification B 751.8. Mechanical Properties and Other Requirements8.1 Mechanical PropertiesThe material shall conform tothe mechanical property requirements specified in Table 2. Onetest is required for each lot as defined in Specification B 751.8.2 Flattening Test A flattening test shall b
18、e made on eachend of one tube per lot. Superficial ruptures resulting fromsurface imperfections shall not be cause for rejection.8.3 Flange Test A flange test shall be made on each end ofone tube per lot.8.4 Nondestructive Test RequirementsEach tube shall besubjected to either a pressure test or a n
19、ondestructive electrictest at the manufacturers option. The purchaser may specifywhich test is to be used.9. Keywords9.1 welded tube; N08020; N08024; N08026SUPPLEMENTARY REQUIREMENTSThe following supplementary requirements shall be applied only when specified by the purchaserin the inquiry, contract
20、, or order:S1. Corrosion TestsS1.1 One intergranular corrosion test per lot shall be per-formed by the manufacturer on a sensitized specimen andtested in accordance with Practices A 262. When this supple-mentary requirement is specified, the specific practice (PracticeB or Practice E) shall also be
21、specified. If Practice B isspecified, the specimen must pass with a rate of less than 0.002in. (0.05 mm) per month. A lot for intergranular corrosiontesting shall be the same as for mechanical testing.S1.1.1 In addition to the anneal recommended in Note 1, thespecimen shall be sensitized for1hat1250
22、F (677C) beforebeing subjected to corrosion testing.S1.1.2 If any corrosion test specimen fails the test, thematerial represented by such specimens may be reheat-treatedand resubmitted for test.ASTM International takes no position respecting the validity of any patent rights asserted in connection w
23、ith 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 responsible tec
24、hnical 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 careful considera
25、tion 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 International, 100 Barr H
26、arbor 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(w
27、ww.astm.org).TABLE 1 Chemical RequirementsElementComposition,%UNS N08020 UNS N08024 UNS N08026Carbon, max 0.07 0.03 0.03Manganese, max 2.00 1.00 1.00Phosphorus,max0.045 0.035 0.03Sulfur, max 0.035 0.035 0.03Silicon, max 1.00 0.50 0.50Nickel 32.0038.00 35.0040.00 33.0037.20Chromium 19.0021.00 22.5025
28、.00 22.0026.00Molybdenum 2.003.00 3.505.00 5.006.70Copper 3.004.00 0.501.50 2.004.00Columbium(Nb) +8 3 carbon1.00 0.150.35tantalumNitrogen . . 0.100.16IronAremainder remainder remainderABy difference.TABLE 2 Mechanical Property RequirementsTensile Strength,min, ksi (MPa)Yield Strength,min, ksi (MPa)Elongation in 2 in.(50.8 mm), min, %80 (551) 35 (241) 30.0B468042
