1、Designation:A742/A742M13American Association State Highway andTransportation Officials StandardAASHTO No.M 246/M 246MStandard Specification forSteel Sheet,Metallic Coated and Polymer Precoated forCorrugated Steel Pipe1This standard is issued under the fixed designation A742/A742M;the number immediat
2、ely following the designation indicates the yearof original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been ap
3、proved for use by agencies of the Department of Defense.1.Scope*1.1 This specification covers polymer precoated steel sheetfor corrugated steel pipe(CSP)which is coated after metalliccoating on continuous lines by coil coating(roller coating orlaminating)processes.The metallic coating is either zinc
4、,55%aluminum-zinc alloy,or zinc-5%aluminum-mischmetal alloy.Sheet for this purpose is furnished flat in coils,flat in cutlengths,or corrugated in cut lengths,all being protected by amill-applied polymer coating on both sides.1.2 The values stated in either inch-pound units or SI unitsare to be regar
5、ded separately as the standard.Within the text,the SI units are shown in brackets.The values stated in eachsystem are not equivalents;therefore,each system must beused independently of the other.1.3 The following precautionary caveat refers only to thetest method portion,Section 9,of this specificat
6、ion:Thisstandard does not purport to address all of the safety concerns,if any,associated with its use.It is the responsibility of the userof this standard to establish appropriate safety and healthpractices and determine the applicability of regulatory limita-tions prior to use.2.Referenced Documen
7、ts2.1 ASTM Standards:2A929/A929M Specification for Steel Sheet,Metallic-Coatedby the Hot-Dip Process for Corrugated Steel PipeD543 Practices for Evaluating the Resistance of Plastics toChemical ReagentsD658 Test Method for Abrasion Resistance of OrganicCoatings by Air Blast Abrasive(Withdrawn 1996)3
8、D1005 Test Method for Measurement of Dry-Film Thick-ness of Organic Coatings Using MicrometersD2794 Test Method for Resistance of Organic Coatings tothe Effects of Rapid Deformation(Impact)G22 Practice for Determining Resistance of Plastics toBacteria(Withdrawn 2002)3G23 Practice for Operating Light
9、-Exposure Apparatus(Carbon-Arc Type)With and Without Water for Exposureof Nonmetallic Materials(Withdrawn 2000)3G62 Test Methods for Holiday Detection in Pipeline Coat-ings3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 fabricatorin this specification,fabricator refers tothe pr
10、oducer of the pipe.3.1.2 manufacturerin this specification,manufacturer re-fers to the producer of the sheet.3.1.3 purchaserin this specification,purchaser refers tothe purchaser of the finished pipe.3.2 Abbreviations:3.2.155 Al-Zn55%aluminum-zinc.3.2.2MMmischmetal.3.2.3Zn-5 Al-MMzinc-5%aluminum-mis
11、chmetal.4.Classification4.1 The polymer coating is classified by grade correspond-ing to the thickness in mils(thousandths inch)on each side ininch-pound units and the thickness in micrometres on each sidein SI units.GradeCoating Thicknessin.m10/10 250/2500.010/0.010250/2504.2 Any combination of pol
12、ymer coating thickness otherthan shown above is subject to agreement between the manu-facturer and purchaser or fabricator.1This specification is under the jurisdiction of ASTM Committee A05 onMetallic-Coated Iron and Steel Products and is the direct responsibility ofSubcommittee A05.17 on Corrugate
13、d Steel Pipe Specifications.Current edition approved April 1,2013.Published April 2013.Originallyapproved in 1977.Last previous edition approved in 2008 as A742/A742M 03(2008).DOI:10.1520/A0742_A0742M-13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Servi
14、ce at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.*A Summary of Changes section appears at the end of this standardCopyright AST
15、M International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Ordering Information5.1 The polymer precoated sheet covered by this specifica-tion shall be ordered only to the specified thickness listed inTable 1.The specified thickness is based on the thickness of
16、 themetallic-coated steel sheet,not including the thickness of thepolymer coating.5.2 Orders for material to this specification shall include thefollowing information,as necessary,to adequately describe thedesired product.5.2.1 Name of material(polymer precoated steel sheet forCSP),5.2.2 Type of metallic coating(see 6.1),5.2.3 ASTM designation and year of issue,as A742 _for inch-pound units or A742M _ for SI units,5.2.4 Corrugation size,if corrugated(see 6.3),5.2.5 Substrate dimensions(specified
