1、Designation: B468 10Standard Specification forWelded UNS N08020 Alloy Tubes1This standard is issued under the fixed designation B468; 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 parenthese
2、s indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification2covers welded UNS N08020 alloyboiler, heat exchanger, and condenser tubes for generalcorrosion-resisting and low- or high-temperature s
3、ervice.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 Specifi-cation B751 lists the dimensional requirements of these sizes.Tubes having other dimensions may be furnishe
4、d providedsuch tubing complies with all other requirements of thisspecification.1.3 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.4 T
5、his standard does not purport to address 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 (MSDS) for this product/materialas prov
6、ided by the manufacturer, to establish appropriatesafety and health practices, and determine the applicability ofregulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3A262 Practices for Detecting Susceptibility to IntergranularAttack in Austenitic Stainless SteelsB751 Specif
7、ication for General Requirements for Nickeland Nickel Alloy Welded TubeB899 Terminology Relating to Non-ferrous Metals andAlloys3. Terminology3.1 Definitions:3.1.1 Definitions for terms defined in Terminology B899shall apply unless otherwise defined by the requirements of thisdocument.4. General Req
8、uirements4.1 Material furnished in accordance with this specificationshall conform to the applicable requirements of the currentedition of Specification B751 unless otherwise providedherein.5. Ordering Information5.1 It is the responsibility of the purchaser to specify allrequirements that are neces
9、sary for material ordered under thisspecification. 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 d
10、esignation,5.1.6 Product Analysis State 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
11、 The tubing shall be made from flat-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 TreatmentTubing of UNS
12、N08020 alloy shall befurnished in the stabilized-annealed condition.1This specification is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and Alloys and is the direct responsibility of SubcommitteeB02.07 on Refined Nickel and Cobalt and Their Alloys.Current edition approved June 1,
13、 2010. Published June 2010. Originallyapproved in 1968. Last previous edition approved in 2009 as B468 04 (2009).DOI: 10.1520/B0468-10.2For ASME Boiler and Pressure Vessel Code applications, see related Specifi-cation SB-468 in Section II of that code.3For referenced ASTM standards, visit the ASTM w
14、ebsite, 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.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Har
15、bor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1The recommended annealing temperatures are 1800 to1850F (982 to 1010C) for UNS N08020.7. Chemical Composition7.1 The material shall conform to the composition limitsspecified in Table 1. One test is required for each lot a
16、s definedin Specification B751.7.2 If a product analysis is performed, it shall meet thechemistry limits prescribed in Table 1, subject to the analysistolerances specified in Table 6 of Specification B751.8. Mechanical Properties and Other Requirements8.1 Mechanical PropertiesThe material shall conf
17、orm tothe mechanical property requirements specified in Table 2. Onetest is required for each lot as defined in Specification B751.8.2 Flattening TestA flattening test shall be made on eachend of one tube per lot. Superficial ruptures resulting fromsurface imperfections shall not be cause for reject
18、ion.8.3 Flange TestA 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 nondestructive electrictest at the manufacturers option. The purchaser may specifywhich test is to be used.9. Keywords9.1 welde
19、d tube; N08020SUPPLEMENTARY REQUIREMENTSThe following supplementary requirements shall be applied only when specified by the purchaserin the inquiry, contract, or order:S1. Corrosion TestsS1.1 One intergranular corrosion test per lot shall be per-formed by the manufacturer on a sensitized specimen a
20、ndtested in accordance with Practices A262. When this supple-mentary requirement is specified, the specific practice (PracticeB or Practice E) shall also be 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 cor
21、rosiontesting shall be the same as for mechanical testing.S1.1.1 In addition to the anneal recommended in Note 1, thespecimen shall be sensitized for1hat1250F (677C) beforebeing subjected to corrosion testing.S1.1.2 If any corrosion test specimen fails the test, thematerial represented by such speci
22、mens may be reheat-treatedand resubmitted for test.SUMMARY OF CHANGESCommittee B02 has identified the location of selected changes to this standard since the last issue(B468 - 04 (2009) that may impact the use of this standard. (Approved June 1, 2010.)(1) Removed N08024 and N08026.TABLE 1 Chemical R
23、equirementsElementComposition,%UNS N08020Carbon, max 0.07Manganese, max 2.00Phosphorus,max0.045Sulfur, max 0.035Silicon, max 1.00Nickel 32.0038.00Chromium 19.0021.00Molybdenum 2.003.00Copper 3.004.00Columbium(Nb) +8 3 carbon1.00tantalumNitrogen .IronAremainderABy difference.TABLE 2 Mechanical Proper
24、ty RequirementsTensile Strength,min, ksi (MPa)Yield Strength,min, ksi (MPa)Elongation in 2 in.(50.8 mm), min, %80 (551) 35 (241) 30.0B468 102ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this
25、 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 technical committee and must be reviewed every five year
26、s 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 consideration at a meeting of theresponsible technical committ
27、ee, 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 Harbor Drive, PO Box C700, West Conshohocken, PA 19428
28、-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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).B468 103
