TM_A_618_
_A_618M_
_04_2015
Designation:A618/A618M04(Reapproved 2015)Standard Specification forHot-Formed Welded and Seamless High-Strength Low-AlloyStructural Tubing1This standard is issued under the fixed designation A618/A618M;the number immediately 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 approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This specification covers grades of hot-formed weldedand seamless high-strength low-alloy square,rectangular,round,or special shape structural tubing for welded,riveted,orbolted construction of bridges and buildings and for generalstructural purposes.When the steel is used in weldedconstruction,the welding procedure shall be suitable for thesteel and the intended service.1.2 Grade II has atmospheric corrosion resistance equiva-lent to that of carbon steel with copper(0.20 minimum Cu)Grades Ia and Ib have atmospheric corrosion resistance sub-stantially better than that of Grade II(Note 1).When properlyexposed to the atmosphere,Grades Ia and Ib can be used bare(unpainted)for many applications.When enhanced corrosionresistance is desired,Grade III,copper limits may be specified.NOTE1For methods of estimating the atmospheric corrosion resis-tance of low alloy steels see Guide G101 or actual data.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.Within the text,theSI units are shown in brackets.The values stated in eachsystem may not be exact equivalents;therefore,each systemshall be used independently of the other.Combining valuesfrom the two systems may result in non-conformance with thestandard.2.Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testingof Steel ProductsA700 Guide for Packaging,Marking,and Loading Methodsfor Steel Products for ShipmentA751 Test Methods,Practices,and Terminology for Chemi-cal Analysis of Steel ProductsG101 Guide for Estimating the Atmospheric Corrosion Re-sistance of Low-Alloy Steels3.Ordering Information3.1 Orders for material under this specification shouldinclude the following as required to describe the materialadequately:3.1.1 Quantity(feet,metres,or number of lengths),3.1.2 Grade(Table 1 and Table 2),3.1.3 Material(round,square,or rectangular tubing),3.1.4 Method of manufacture(seamless,buttwelded,orhot-stretch-reduced electric-resistance welded),3.1.5 Size(outside diameter and nominal wall thickness forround tubing and the outside dimensions and calculated nomi-nal wall thickness for square and rectangular tubing),3.1.6 Length(specific or random,see 8.2),3.1.7 End condition(see 9.2),3.1.8 Burr removal(see 9.2),3.1.9 Certification(see 12.1),3.1.10 Specification designation(A618 or A618M,includ-ing yeardate),3.1.11 End use,and3.1.12 Special requirements.4.Process4.1 The steel shall be made by one or more of the followingprocesses:open-hearth,basic-oxygen,or electric-furnace.4.2 Steel may be cast in ingots or may be strand cast.Whensteels of different grades are sequentially strand cast,identifi-cation of the resultant transition material is required.Theproducer shall remove the transition material by any estab-lished procedure that positively separates the grades.5.Manufacture5.1 The tubing shall be made by the seamless,furnace-buttwelded(continuous-welded),or hot-stretch-reducedelectric-resistance-welded process.1This specification is under the jurisdiction of ASTM Committee A01 on Steel,Stainless Steel and Related Alloys and is the direct responsibility of SubcommitteeA01.09 on Carbon Steel Tubular Products.Current edition approved Sept.1,2015.Published September 2015.Originallyapproved in 1968.Last previous edition approved in 2010 as A618/A618M04(2010).DOI:10.1520/A0618_A0618M-04R15.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Chemical Composition6.1 When subjected to the heat and product analysis,respectively,the steel shall conform to the requirementsprescribed in Table 1.6.1.1 For Grades Ia and Ib,the choice and use of alloyingelements,combined with carbon,manganese,and sulfur withinthe limits prescribed in Table 1 to give the mechanicalproperties prescribed in Table 2 and to provide the atmosphericcorrosion resistance of 1.2,should be made by the manufac-turer and included and reported in the heat analysis forinformation purposes only to identify the type of steel applied.For Grades Ia and Ib material,the atmospheric corrosion-resistance index,calculated on the basis of the chemicalcomposition of the