1、Designation: A498/A498M 14A498/A498M 17Standard Specification forSeamless and Welded Carbon Steel Heat-Exchanger Tubeswith Integral Fins1This standard is issued under the fixed designation A498/A498M; 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*1.1 This specification covers external helical, integral finned, describes seamless or weld
3、ed low-carbon steel tubes for use onwhich the external or internal surface, or both, have been modified by a cold forming process to produce an integral increasedsurface area for improved heat transfer. The tubes are used in tubular heat exchangers, surface condensers, evaporators,superheaters, and
4、similar heat-transfer apparatus in unfinned end outside diameters up to 2 in. 50 mm, inclusive.1.2 UnitsThis specification is expressed in both inch-pound units and in SI units; however, unless the purchase order orcontract specifies the applicable M specification designation (SI units), the inch-po
5、und units shall apply. The values stated in eitherinch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. Thevalues stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other
6、.Combining values from the two systems may result in non-conformance with the standard.1.3 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Gu
7、ides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2A179/A179M Specification for Seamless Cold-Drawn Low-Carbon Steel Heat-Exchanger and Condenser TubesA214/A214M Specification for Electric-Resistance-W
8、elded Carbon Steel Heat-Exchanger and Condenser TubesA334/A334M Specification for Seamless and Welded Carbon and Alloy-Steel Tubes for Low-Temperature ServiceA450/A450M Specification for General Requirements for Carbon and Low Alloy Steel TubesA941 Terminology Relating to Steel, Stainless Steel, Rel
9、ated Alloys, and FerroalloysA1016/A1016M Specification for General Requirements for Ferritic Alloy Steel, Austenitic Alloy Steel, and Stainless SteelTubesA1047/A1047M Test Method for Pneumatic Leak Testing of Tubing3. Terminology3.1 DefinitionsFor definitions of general terms used in this specificat
10、ion, refer to Terminology A941.3.2 Definitions of Terms Specific to This Standard:3.2.1 landa length of unmodified tube between adjacent sections of modified tube; used as support zones for baffles, or forbending where surface modification might compromise material integrity, or for other reasons.3.
11、2.2 modified surfacethe surface of a tube having a series of integral fins, grooves, or ribs on the outside diameter, insidediameter, or both, for the purpose of increasing the surface area and improving heat transfer.3.2.3 unmodified surfacethe cylindrical surface of a tube made to the reference st
12、andards.3.3 Symbols (Integral Fin Tube Nomenclature):3.3.1 Bare tube symbols, see Fig. 1, Fig. 2, or Fig. 3.1 This specification is under the jurisdiction ofASTM Committee A01 on Steel, Stainless Steel and RelatedAlloys and is the direct responsibility of Subcommittee A01.09on Carbon Steel Tubular P
13、roducts.Current edition approved May 1, 2014March 15, 2017. Published May 2014May 2017. Originally approved in 1963. Last previous edition approved in 20062014 asA498 06.A498/A498M 14. DOI: 10.1520/A0498_A0498M-14.10.1520/A0498_A0498M-17.2 For referencedASTM standards, visit theASTM website, www.ast
14、m.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM 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 ch
15、anges have been made to the previous version. Becauseit may not be technically possible 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 off
16、icial document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.3.1.1 OD = outside diameter of unmodified sections, and3.3.1.2 W = wall thickness of unmodified sections
17、.3.3.2 OD surface modification symbols, see Fig. 1.3.3.2.1 od = outside diameter of modified sections,3.3.2.2 rd = root diameter of outside fins,3.3.2.3 Wf = wall thickness at fin groove, either minimum or average,3.3.2.4 FH = fin height,3.3.2.5 Nfpu = number of fins per unit length, the reciprocal
18、of p,3.3.2.6 p = pitch, the distance from a point on one fin to the corresponding point on the adjacent fin along the tube longitudinalaxis, and3.3.2.7 p = the reciprocal of Nfpu.3.3.3 ID surface modification symbols, see Fig. 2.3.3.3.1 od = outside diameter of modified sections,3.3.3.2 id = inside
19、diameter of id modified sections, to root of rib,3.3.3.3 Wr = wall thickness at rib groove, either minimum or average,3.3.3.4 RH = rib height,3.3.3.5 RW = rib width,3.3.3.6 HA = helix angle,3.3.3.7 p = pitch, the distance from a point on one rib to the corresponding point on the adjacent rib along t
20、he tube longitudinalaxis, and3.3.3.8 Nrac = number of ribs around circumference.3.3.4 Combined (OD + ID) surface modification symbols, see Figs. 1-3.3.3.4.1 od = outside diameter of modified sections,3.3.4.2 id = inside diameter of modified sections, to root of rib, and3.3.4.3 Wc = wall thickness of
21、 combined modified surface, either minimum or average.3.3.5 Length symbols, see Fig. 3.FIG. 1 OD Surface Modification Symbols FinsFIG. 12 Finned Tube NomenclatureID Surface Modification Symbols RibsFIG. 3 Combined OD and ID Surface Modifications Plus Length SymbolsA498/A498M 1723.3.5.1 LOA = overall
22、 length,3.3.5.2 LBE1 = length of first bare end,3.3.5.3 LBE2 = length of second bare end,3.3.5.4 LI1 = length to first intermediate land,3.3.5.5 LIL1 = length of first intermediate land,3.3.5.6 LI2 = length to second intermediate land,3.3.5.7 LIL2 = length of second intermediate land,3.3.5.8 LIn = l
23、ength to nth intermediate land, and3.3.5.9 LILn = length of nth intermediate land.3.4 IllustrationsSee Figs. 1-3.4. Ordering Information4.1 The purchaser shall specify in the order the plain-tube specification and the alloy from which the finned tube is to bemanufactured. It is the responsibility of
24、 the purchaser to specify requirements that are necessary for tubing ordered under thisspecification. Such requirements may include, but are not limited to, the following:4.1.1 ASTM designation and year of issue for the modified tube (this specification).4.1.2 ASTM designation and year of issue of t
25、he plain tube from which the modified tube is to be manufactured.4.1.3 Grade (if applicable).4.1.4 Type of material (if applicable: seamless or welded).4.1.5 Quantity.4.1.6 Dimensions:4.1.6.1 Outside diameter.4.1.6.2 Wall thickness.4.1.6.3 Length.4.1.6.4 All other desired dimensional attributes as d
26、escribed in 3.3.2 3.3.5. Configuration of these modified surface attributesshall be as agreed between the purchaser and the manufacturer.4.1.7 Temper (as-cold-worked or annealed).4.1.8 Packaging.4.1.9 Customer inspection.4.1.10 Certification.4.1.11 Special requirements and any supplementary requirem
27、ents selected.3.2 The purchaser shall specify in the order the diameter, wall thickness, and length of unfinned sections; root diameter and wallthickness of the finned section; number of fins per unit length; and the total tube length.5. Material and Manufacture5.1 The finned modified surface tubes
28、shall be manufactured from plain tubes that conform to one of the following ASTMSpecifications: A179/A179M, A214/A214M, or A334/A334M.4.2 Any tests that are required in the plain-tube specifications that are performed on unfinned lengths of tube in accordance withthis specification need not be perfo
29、rmed on the plain tube.5.2 The fins modified surface tubes shall be produced by the cold forming of steel prime-surface tube.plain tubes. To complywith this specification, the fin modified surface and tube material must be homogeneous. integral.5.3 Finned Modified surface tubes shall normally be fur
30、nished with unfinnedunmodified ends, but may be furnished with finnedmodified surface ends if specified.6. Heat Treatment Temper6.1 The tube after finningmodification shall be supplied in either the annealed or as-fabricated as-cold-worked condition, oneof which shall be specified on the purchaser o
31、rder.6.2 The annealed condition is defined as having both the finnedmodified and unfinnedunmodified portions of the tubeconforming to the applicable heat-treatment requirements of the governingASTM specification for the steel tube analysis involved.specified ASTM plain tube.6.3 The as-fabricatedas-c
32、old-worked condition is defined as having the finnedmodified portions of the tube in the as-finned orcold-worked condition produced by the finning operationmodifying operation; and the unfinned or plain tube unmodified portionsof the finned tube in the as-fabricated condition suitable for rolling-in
33、 operations. confirming to the heat-treatment requirementsof the specified ASTM plain tube.A498/A498M 1737. Chemical Composition7.1 The steel shall conform to the chemical requirements prescribed in the governing plain-tube specification.8. Tensile Requirements8.1 The tube prior to the finning opera
34、tion, or unfinned modifying operation, and the unmodified portions of the finned tube,shall conform to the applicable requirements for tensile properties prescribed in the governing plain-tube specification.8. Pressure Test8.1 Each tube after finning shall be subjected to an internal air pressure of
35、 250 psi 1.7 MPa minimum for 5 s without showingevidence of leakage. Any evidence of leakage shall be cause for rejection. The test method used shall permit easy visual detectionof any leakage, such as testing the tube under water or by the pressure differential method.39. Dimensions and Permissible
36、 Variations9.1 DiameterThe outside diameter of the unfinned sections unmodified sections and the modified sections shall not exceedthe diameter tolerances as specified in the governing prime-surfaceplain tube specification (seeas Fig. 1). measured withmicrometers and verified by a “go” ring gauge. T
37、he dimensions of the ring gauge shall be as described in 9.1.1.9.1.1 The inside diameter of the “go” ring gauge shall be equal to the nominal tube diameter, plus the maximum diametertolerance allowed by the governing plain tube specification, plus 0.002 in. 0.05 mm. The length of the ring gauge shal
38、l be notless than 1 in. 25 mm.9.2 Wall ThicknessThickness ToleranceNo tube at its thinnest point beneath the fins or in the plain section shall be lessthanWall thickness is defined as the thickness “under the fin groove”, “under the rib groove”, or the combination of both, asillustrated in Figs. 1-3
39、the minimum thickness specified. .9.2.1 Tubes Ordered to Minimum Wall Thickness at the Modified SectionNo tube at its thinnest point in the modified sectionshall be less than the minimum specified wall thickness; nor greater than 18 % over the specified wall thickness.9.2.2 Tubes Ordered to Average
40、Wall Thickness at the Modified SectionNo tube at its thinnest point in the modified sectionshall be less than 9 % under the specified wall thickness; nor greater than 9 % over the specified wall thickness.9.3 LengthLength Tolerance: The length of the tubes shall not be less than that specified when
41、measured at a temperature of68 F (20 C, but may exceed the specified value by the amounts given in Table 1.9.3.1 Overall LengthThe length of the tubes shall not be less than that specified when measured at a temperature of 68 F 20C, but may exceed the specified value by the amounts given in Table 1.
42、9.3.2 Length of Bare EndsThe length of bare ends shall not be less than specified, nor 12 in. 13 mm greater than specified.9.3.3 Length to Intermediate LandsThe length to intermediate lands shall not be greater than specified, nor 12 in. 13 mmless than specified.9.3.4 Length of Intermediate LandsThe
43、 length of intermediate lands shall not be less than specified, nor 1 in. 25 mm greaterthan specified.9.4 Configuration of ModificationsConfiguration of modifications (fins per unit length, fin pitch, fin height, fin geometry, ribheight, rib width, rib geometry, helix angle, rib pitch, etc.) shall b
44、e as agreed between purchaser and manufacturer.10. Workmanship and Finish10.1 Finished tubes shall be reasonably straight and have smooth ends free from burrs. They shall be free from injurious defectsand shall have a workmanlike finish. A slight amount of oxidation will not be considered as scale.1
45、1. Pneumatic Test11.1 At the completion of modifying operations, each tube shall be subjected to a pneumatic test at a pressure of not less than250 psi 1.72 MPa. At the option of the manfuacturer, this can either be the Air Under Water Test or the Pneumatic Leak Test.11.1.1 Air Under Water TestThis
46、test is to be in accord with Specification A450/A450M or Specification A1016/A1016M.11.1.2 Pneumatic Leak TestThis test is to be in accord with Specification A450/A450M or Specification A1016/A1016M, andTest Method A1047/A1047M.TABLE 1 Tolerances for Specified Length of TubesSpecified Length, ft m T
47、olerance, in. mmUp to 24 7.3, incl +18 3Over 24 to 34 7.3 to 10.4, incl +14 6Over 34 to 44 10.4 to 13.4, incl +38 9Over 44 13.4 +12 13 maxA498/A498M 174NOTE 1Tubes made to Specifications A179/A179M and A214/A214M also comply with the general requirements of Specification A450/A450M.Tubes made to Spe
48、cification A334/A334M also comply with the general requirements of Specification A1016/A1016M. Reference the appropriate generalrequirements for testing details.12. Package Marking12.1 The name or brand of the manufacturer, name and order number of the purchaser, plain tube specification, condition(
49、annealed or as-fabricated), Specification A498/A498M tube diameter, wall thickness, and tube length , plain tube specification,Grade (if applicable), Type of Material (seamless or welded), Quantity, Tube Diameter, Tube Wall Thickness, and Tube Length,Temper (annealed or as-cold-worked) shall be marked on a tag securely attached to the bundle or box in which the tubes areshipped. The marking need not include the year of issue of the specification.12.2 Bar CodingIn addition to the requirements stated
