1、Designation: A556/A556M 96 (Reapproved 2012)A556/A556M 18Standard Specification forSeamless Cold-Drawn Carbon Steel Feedwater HeaterTubes1This standard is issued under the fixed designation A556/A556M; the number immediately following the designation indicates the yearof original adoption or, in the
2、 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.1. Scope Scope*1.1 This specification2 covers minimum-wall-thickness, seamless cold-drawn carbon st
3、eel tubes including bending into the formof U-tubes, if specified, for use in tubular feedwater heaters.1.2 The tubing sizes covered shall be 58 to 114-in. 15.9 to 31.8-mm outside diameter, inclusive, with minimum wallthicknesses equal to or greater than 0.045 in. 1.1 mm.1.3 Optional supplementary r
4、equirements are provided, and when desired, shall be stated in the order.1.4 The values stated in either inch-pound units or SI units are to be regarded separately as the standard. Within the text, theSI units are shown in brackets. The values stated in each system are not exact equivalents; therefo
5、re, each system must be usedindependently of the other. Combining values from the two systems may result in nonconformance with the specification. Theinch-pound units shall apply unless the “M” designation of this specification is specified in the order.1.5 This international standard was developed
6、in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1
7、 ASTM Standards:3A450/A450M Specification for General Requirements for Carbon and Low Alloy Steel TubesE30A751 Test Methods Methods, Practices, and Terminology for Chemical Analysis of Steel, Cast Iron, Open-Hearth Iron, andWrought IronSteel Products (Withdrawn 1995)3. Ordering Information3.1 Orders
8、 for material under this specification should include the following as required to describe the desired materialadequately:3.1.1 Quantity (feet, metres, or number of pieces),3.1.2 Name of material (seamless steel tubing),3.1.3 Dimensions (outside diameter and minimum wall thickness),3.1.4 Length (sp
9、ecific or random),3.1.5 Manufacture (cold drawn),3.1.6 Grade (chemical composition),3.1.7 Optional requirements,3.1.8 Bending RequirementsIf order specifies tubes to be bent, the design of the U-tubes shall accompany the order. Purchasermust specify if stress-relief anneal of the U-bends is required
10、,3.1.9 Test report required (see Certification Section of Specification A450/A450M),3.1.10 Specification number, and3.1.11 Special requirements and any supplementary requirements selected.1 This specification is under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and RelatedAlloys
11、and is the direct responsibility of Subcommittee A01.09on Carbon Steel Tubular Products.Current edition approved March 1, 2012Sept. 1, 2018. Published November 2012September 2018. Originally approved in 1965. Last previous edition approved in20052012 as A556/A556M 96 (2005).(2012). DOI: 10.1520/A055
12、6_A0556M-96R12. 10.1520/A0556_A0556M-18.2 For ASME Boiler and Pressure Vessel Code applications see related Specification SA-556 in Section II of that Code.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM
13、 Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically pos
14、sible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCo
15、pyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14. General Requirements4.1 Material furnished to this specification shall conform to the applicable requirements of the current edition of theSpecification A450/A450M, unless otherwise pro
16、vided herein.5. Manufacture5.1 ManufactureTubes shall be made by the seamless process and shall be cold drawn.5.2 Heat Treatment:5.2.1 Cold-drawn tubes shall be heat treated after the final cold-draw pass at a temperature of 1200F 640C or higher toensure ductility satisfactory for rolling into tube
17、sheets and to meet mechanical properties as specified.5.2.2 If stress-relief anneal of the U-bends is specified, the anneal shall consist of heating the bent portion within a range of 1100to 1200F 585 to 640C.6. Chemical Composition6.1 The steel shall conform to one of the requirements as to chemica
18、l composition as prescribed in Table 1.6.2 When a grade is ordered under this specification, supplying an alloy grade that specifically requires the addition of anyelement other than those listed for the ordered grade in Table 1 is not permitted.7. Product Analysis7.1 When requested in the purchase
19、order, a product analysis shall be made by the manufacturer or supplier from one tube orbillet per heat.7.2 If the original test for product analysis fails, retests of two additional tubes or billets shall be made. Both retests for theelements in question shall meet the requirements of this specific
20、ation; otherwise, all remaining material in the heat or lot (Note1) shall be rejected or, at the option of the producer, each tube may be individually tested for acceptance. Tubes that do not meetthe requirements of this specification shall be rejected.NOTE 1For tension and hardness test requirement
21、s, the term lot applies to all tubes prior to cutting, of the same nominal diameter and wall thicknesswhich are produced from the same heat of steel. When final heat treatment is in a batch-type furnace, a lot shall include only those tubes of the samesize and the same heat which are heat treated in
22、 the same furnace charge. When the final heat treatment is in a continuous furnace, a lot shall includeall tubes of the same size and heat, heat treated in the same furnace at the same temperature, time at heat and furnace speed.7.3 For referee purposes, Test Methods E30A751 shall be used.8. Mechani
23、cal Properties8.1 Tensile PropertiesThe material shall conform to the requirements as to tensile properties prescribed in Table 2, whenpulled in full section.8.2 Hardness RequirementsThe tubes shall not exceed the Rockwell Hardness shown in Table 3.9. Permissible Variations in Dimensions (Fig. 1)9.1
24、 Permissible variations from the specified outside diameter shall not exceed 60.004 in. 0.10 mm for tubing under 1.0-in.25.4-mm outside diameter nor 60.006 in. 0.15 mm for tubing 1.0 in. 25.4 mm to 1.25 in. 31.7 mm inclusive. Thesetolerances do not apply to the bent portion of the U-tubes.At the ben
25、t portion of a U-tube for R = 2 D or greater neither the majornor minor diameter of tube shall deviate from nominal by more than 10 %. If 112 D is specified, tolerances could be greater.9.2 Permissible variations from the specified minimum wall thickness shall not exceed +20 % or 0. The wall thickne
26、ss of thetube in U-bent section shall be not less than value determined by:tf 5T 2R!/2R1D! (1)where:tf = wall thickness after bending, in. mm,T = specified minimum tube wall thickness, in. mm,TABLE 1 Chemical RequirementsElement Composition, %Grade A2 Grade B2 Grade C2Carbon, max 0.18 0.27 0.30Manga
27、nese 0.270.63 0.290.93 0.291.06Phosphorus, max 0.035 0.035 0.035Sulfur, max 0.035 0.035 0.035Silicon, min . 0.10 0.10A556/A556M 182R = centerline bend radius, in. mm, andD = nominal outside tube diameter, in. mm.9.3 In the case of U-tubes, the length of the tube legs as measured from the point of ta
28、ngency of the bend and the tube leg tothe end of the tube leg shall not be less than specified, but may exceed the specified values by the amount given in Table 4. Thedifference in lengths of the tube legs shall not be greater than 18 in. 3 mm unless otherwise specified.9.4 The end of any tube may d
29、epart from square by not more than the amount given in Table 5.9.5 The leg spacing measured between the points of tangency of the bend to the legs shall not vary from the value (2R specified tube OD) by more than 116 in. 1.5 mm where R is the centerline bend radius.9.6 The bent portion of the U-tube
30、 shall be substantially uniform in curvature and not exceed 6116 in. 61.5 mm of the normalcenterline radius.10. Workmanship, Finish, and Appearance10.1 Finished tubes shall be free from scale but may have a superficial oxide film on the surfaces. A light oxide scale on theoutside and inside surfaces
31、 of U-bend shall be allowed for tubes which have been heat treated.10.2 Finished tubes shall be reasonably straight and have smooth ends free from burrs. Tubes shall have a workmanlike finishand shall be free of surface imperfections that cannot be removed within the allowable wall tolerances. Remov
32、al of surfaceimperfections such as handling marks, straightening marks, light mandrel and die marks, shallow pits, and scale pattern will notbe required provided they are within the allowable wall tolerances.10.3 Finished tubes shall be coated both on the outside and the inside diameter to prevent c
33、orrosion in transit. The type ofcoating applied should be mutually agreed upon and specified in the order.11. Mechanical Tests Required11.1 Tension TestOne tension test shall be made on a specimen for lots of not more than 50 tubes. Tension tests shall be madeon specimens from two tubes for lots of
34、more than 50 tubes (Note 1).11.2 Flattening TestOne flattening test shall be made on specimens taken from each end of one finished tube, not the one usedfor the flaring test, from each lot of not more than 125 tubes or fraction thereof.11.3 Flaring TestOne flaring test shall be made on specimens tak
35、en from each end of one finished tube, not the one used forflattening test, from each lot of not more than 125 tubes or fraction thereof.11.4 Hardness TestBrinell or Rockwell hardness tests shall be made on specimens from two tubes from each lot (Note 1).11.5 Hydrostatic TestEach U-tube shall be sub
36、jected to a hydrostatic test, using a noncorrosive fluid, or when agreed uponbetween the purchaser and manufacturer, they may be tested at 112 times the specified design working pressure.12. Nondestructive Test (Electric Test)12.1 Each tube shall be tested after the finish heat treatment following t
37、he final cold-drawn pass by passing through anondestructive tester capable of detecting defects on the entire cross section of the tube, in accordance with SpecificationA450/A450M.TABLE 2 Tensile RequirementsGrade A2 Grade B2 Grade C2Tensile strength, min, ksi MPa 47 320 60 410 70 480Yield strength,
38、 min, ksi MPa 26 180 37 260 40 280Elongation in 2 in. or 50 mm,min, % (longitudinal)35 30 30TABLE 3 Hardness RequirementsGrade A2 HR B 72Grade B2 HR B 79Grade C2 HR B 89TABLE 3 Hardness RequirementsGrade A2 72 HRBWGrade B2 79 HRBWGrade C2 89 HRBWA556/A556M 18313. Packaging and Package Marking13.1 Th
39、e tubing shall be packaged or bundled in such a manner as to prevent damage in ordinary handling and transportationand identified by a tag with the name of the manufacturer, purchase order number, specification number and grade, and size.13.2 In the case of U-tubes, each box shall be palletized and
40、legibly marked showing the manufacturers name, purchase ordernumber, specification number and grade, size, and identification of items contained.13.3 Bar CodingIn addition to the requirements in 13.1 and 13.2, bar coding is acceptable as a supplemental identificationmethod. The purchaser may specify
41、 in the order a specific bar coding system to be used.14. Keywords14.1 carbon; feedwater heater tubes; seamless steel tube; steel tubeSUPPLEMENTARY REQUIREMENTSThe following supplementary requirement or requirements may become a part of the specificationwhen specified in the inquiry or invitation to
42、 bid, and purchase order or contract. These requirementsshall not be considered, unless specified in the order, in which even the necessary tests shall be madeby the manufacturer prior to the bending or shipment of the tubing.S1. Nondestructive Ultrasonic TestRound Tubing (Commercial Grade)S1.1 The
43、manufactuer shall test the tubing by an ultrasonic nondestructive test for detection of harmful faults and soundness.S1.1.1 Ultrasonic testing shall be performed using pulse-echo shear wave techniques to locate longitudinal or circumferentialdefects, or both.FIG. 1 Bent Portion of U-TubeTABLE 4 Tube
44、 Leg Length ToleranceLeg Length, ft m Plus Tolerance in. mmUp to 20 6, incl 18 3.2Over 20 to 30 6 to 9, incl 532 4.0Over 30 to 40 9 to 12.2, incl 316 4.8TABLE 5 Squareness of Ends ToleranceTube OD, in. mm Tolerance,in. mm58 15.9 0.010 0.25Over 58 to 114 15.9 to 31.7, incl 0.016 0.4A556/A556M 184S1.1
45、.2 Tubes being tested shall be reasonably straight for proper rotation. The outside and inside diameter surfaces of the tubesshall be free of dirt, grit, grease, oil, loose scale, or other materials which tend to attenuate, scatter, or reflect ultrasonic signals.S1.1.3 Tubing shall be inspected by f
46、eeding spirally past a suitable transducer with rotation of material to be toward thetransducer.S1.1.4 Suitable ultrasonic instrumentation shall be used to clearly distinguish the artificial defects (hereafter called referencenotches) described later. Automatic electronic monitoring of the reflected
47、 ultrasonic signals shall be provided in such manner thatany naturally occurring defects which present an ultrasonic reflection equal to or greater than the reference standard(s) shall triggeraudible and visible alarms.S1.1.5 Instrument calibration as described herein shall be accomplished with the
48、reference standard being rotated and fed pastthe transducer at the same approximate rate at which the tubing under test will be tested.S1.1.6 The following factors will be adjusted so as to achieve optimum instrument distinction between the reference notch(es)and plain portion of tubing when calibra
49、ting equipment to the reference standard:S1.1.6.1 Search unit position shall be such that shear waves are propagated within the tube being tested. If both outside andinside diameter reference notches are used, the optimum angle shall be used which will indicate both notches as close to equal sizeas possible.S1.1.6.2 The test frequency to be used shall be chosen to yield the best distinction between reference notches and plain areasof tubing. In general, 2.25 or 5.
