1、Designation: A254 97 (Reapproved 2007) A254/A254M 12Standard Specification forCopper-Brazed Steel Tubing1This standard is issued under the fixed designation A254;A254/A254M; the number immediately following the designation indicates theyear of original adoption or, in the case of revision, the year
2、of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope1.1 This specification covers double-w
3、all, copper-brazed steel tubing suitable for general engineering uses, particularly in theautomotive, refrigeration, and stove industries for fuel lines, brake lines, oil lines, heating and cooling units, and the like. Thetubing is available in either of two types, single strip or double strip as sh
4、own in Fig. 1.1.2 UnitsThis specification is expressed in both inch-pounds units and in SI units; however, unless the purchase order orcontract specifies the applicable M specification designation (SI units), the inch-pound units shall apply. The values stated in eitherinch-pound units or SI units a
5、re to be regarded separately as the standard. standard. Within the text, the SI units are shown inbrackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently ofthe other. Combining values from the two systems may result in non-conforman
6、ce with the standard. In this specification hard orrationalized conversions apply to diameters, lengths, and tensile properties. Soft conversion applies to other SI measurements.2. Referenced Documents2.1 ASTM Standards:2A370 Test Methods and Definitions for Mechanical Testing of Steel ProductsA751
7、Test Methods, Practices, and Terminology for Chemical Analysis of Steel ProductsE30 Test Methods for Chemical Analysis of Steel, Cast Iron, Open-Hearth Iron, and Wrought Iron (Withdrawn 1995)3E59 Practice for Sampling Steel and Iron for Determination of Chemical Composition (Withdrawn 1996)32.2 Soci
8、ety of Automotive Engineers Standard:4J 533 Flares for Tubing3. Ordering Information3.1 Orders for material under this specification should include the following, as required to describe the desired materialadequately:3.1.1 Quantity (feet, metres), metres or number of pieces),3.1.2 Name of material
9、(copper-brazed steel tubing),3.1.3 Type, single strip or double strip, where necessary (see Fig. 1) (normally the type is not specified),3.1.4 Size (outside diameter and wall thickness; normally inside diameter should not be specified),3.1.5 Length (specific or random),3.1.6 Inside surface cleanline
10、ss where required (see Section 8),3.1.7 External coating, where required (see Section 7 and Supplementary Requirement S2), and3.1.8 Special or supplementary requirements or exceptions to specification.4. Manufacture4.1 The steel may be made by any commercially accepted steelmaking process.4.2 If a s
11、pecific type of melting is required by the purchaser, it shall be as stated on the purchase order.1 This specification is under the jurisdiction of ASTM Committee A01 on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.09on Carbon Steel Tubular Products.
12、Current edition approved Nov. 1, 2007Nov. 1, 2012. Published January 2008December 2012. Originally approved in 1944. Last previous edition approved in 20022007as A254 97(2002).(2007). DOI: 10.1520/A0254-97R07.10.1520/A0254_A0254M-12.2 For referenced ASTM standards, visit the ASTM website, www.astm.o
13、rg, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historical standard is referenced on www.astm.org.4 Available from American Society of Me
14、chanical Engineers (ASME), ASME International Headquarters, Three Park Ave., New York, NY 10016-5990, http:/www.asme.org. SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http:/www.sae.org.This document is not an ASTM standard and is intended only to provide the user of an A
15、STM standard an indication of what changes 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 publishe
16、d by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States14.3 The primary melting may incorporate separate degassing or refining and may be followed by secondary melting, such aselectroslag re
17、melting or vacuum-arc remelting. If secondary melting is employed, the heat shall be defined as all of the ingotsremelted from a single primary heat.4.4 Steel may be cast in ingots or may be strand cast. When steel of different grades is sequentially strand cast, identificationof the resultant trans
18、ition material is required. The producer shall remove the transition material by an established procedure thatpositively separates the grades.4.5 The tubing shall be made by rolling steel strip into the form of tubing and subsequently copper brazing in a reducingatmosphere.4.6 Tubing shall be constr
19、ucted as shown in Fig. 1.4.7 Tubing shall be suitably tested after brazing by the manufacturer to ensure freedom from leaks and detrimental flaws.5. Chemical Composition5.1 The steel shall conform to the requirements as to chemical composition prescribed in Table 1.5.2 Heat AnalysisAn analysis of ea
20、ch heat of steel shall be made by the steel manufacturer to determine the percentages ofthe elements specified. If secondary melting processes are employed, the heat analysis shall be obtained from one remelted ingotor the product of one remelted ingot of each primary melt. The chemical composition
21、thus determined, or that determined froma product analysis made by the tubular product manufacturer shall conform to the requirements specified.5.3 Product AnalysisTubing of this quality is commonlymay be produced in rimmed or capped steel which is characterizedby a lack of uniformity in its chemica
22、l composition. For this reason, rejection for product analysis is not appropriate unlessmisapplication is clearly indicated.5.4 Methods of AnalysisMethods described in Test Methods E30 shall be used for referee purposes. Due allowance shall bemade for the presence of copper brazing metal.5.5 Samples
23、 for Product AnalysisExcept for spectro-graphic analysis, samples shall be taken in accordance with Practice E59.6. Mechanical Requirements6.1 Tension TestTensile properties of tubing as manufactured (prior to cold working) shall conform to the requirementsspecified in Table 2.6.1.1 The specimens an
24、d tension tests required shall be made in accordance with Test Methods and Definitions A370.6.1.2 Specimens shall be tested at room temperature.6.1.3 Test specimens shall be taken from the ends of finished tubes prior to upsetting, swaging, expanding, or other formingoperations, or being cut to leng
25、th. They shall be smooth on the ends and free from burrs and flaws.6.1.4 If any test specimen shows flaws or defective machining, it may be discarded and another specimen substituted.6.1.5 The yield strength shall be determined as that corresponding to a permanent offset of 0.2 % of the gage length
26、of thespecimen, or a total extension of 0.5 % of the gage length under load.6.1.6 If the percentage of elongation of any test specimen is less than that specified and any part of the fracture is more than34 in. (19.0 mm)19 mm from the center of the gage length, as indicated by scribe marks on the sp
27、ecimen before testing, a retestshall be allowed.6.2 Flattening TestA section of tubing, not less than 212 in. (64 mm)65 mm in length, shall stand being flattened betweenparallel plates until the inside walls are in contact without cracking or otherwise showing flaws.FIG. 1 Brazed Tubing, Double-Wall
28、, 360-deg Brazed ConstructionTABLE 1 Chemical RequirementsElement Composition, %Carbon 0.05 to 0.15Manganese 0.27 to 0.63Phosphorus, max 0.035Sulfur, max 0.035A254/A254M 1226.3 Expansion TestA section of tubing approximately 4 in. (100 mm)100 mm in length shall stand being expanded over atapered man
29、drel having a slope of 1 in 10 until the outside diameter at the expanded end is increased 20 % without cracking orotherwise showing flaws. (Prior to the expansion test, tubing shall be cut off square, edge crowned, and deburred. It shall be heldfirmly and squarely in the die, and punch must be guid
30、ed on the axis of the tubing.)6.4 Bend TestThe finished tubing shall stand bending on a centerline radius equal to three times the tubing outside diameterwithout kinking, cracking, or developing other flaws where proper bending fixtures are used.6.5 Pressure Proof TestsEach tube shall be capable of
31、withstanding, without bursting or leaking, either of the following prooftests:6.5.1 An internal hydrostatic pressure sufficient to subject the material to a minimum fiber stress of 16 000 psi (110 MPa).110MPa. Hydrostatic pressure shall be determined by the following formula:P 52St/Dwhere:P = hydros
32、tatic pressure, psi (or MPa),S = allowable fiber stress, 16 000 psi (110 MPa),t = actual wall thickness of tubing, in. (or mm), andD = actual outside diameter of tubing, in. (or mm).P = hydrostatic pressure, psi MPa,S = allowable fiber stress, 16 000 psi 110 MPa,t = actual wall thickness of tubing,
33、in. mm, andD = actual outside diameter of tubing, in. mm.6.5.2 An underwater air pressure between 225 and 250 psi (1.551.55 and 1.73 MPa).MPa.7. Coating7.1 Tubing may be furnished with a copper coating on the inside and outside surfaces, at the option of the manufacturer.8. Inside Surface Cleanlines
34、s8.1 When inside surface cleanliness is specified by the purchaser, tubing for certain uses, such as refrigeration condensers, shallconform to the following requirement for internal cleanliness:8.1.1 When a length of tubing is washed internally with redistilled chloroform or redistilled 1,1,1-trichl
35、oroethane, the residueremaining upon evaporation of the solvent shall not exceed 1.25 104 g/in.2 (0.1940.194 g/m2) of internal surface. To performthe test, pour 100 mL of solvent through the tubing and collect. The total length of tubing tested should not be less than 40 ft (12m),12 m, although this
36、 total length may be obtained by washing several separate lengths and pouring the same solvent througheach in succession. Evaporate the solvent in a steam or hot water bath, and dry at 110C (230F)230F until the vapors arecompletely removed.8.2 To maintain this level of cleanliness in shipping, handl
37、ing, and storage, the purchaser may request that the manufacturer sealthe tube ends with caps or closures.9. Dimensional Tolerances9.1 The tubing shall conform to the permissible variations in Table 3, Table 4, and Table 5.10. Workmanship, Finish, and Appearance10.1 Finished tubing shall be clean, s
38、mooth and round, both inside and outside, and shall be free of rust, scale, and defects thatimpair processing and serviceability. Finished tubes shall be reasonably straight.TABLE 2 Tensile RequirementsProperty RequirementTensile strength, min, psi (MPa) 42 000 (290)Yield strength, min, psi (MPa) 25
39、 000 (172)Elongation in 2 in. (50.8 mm) min, % 25TABLE 2 Tensile RequirementsProperty RequirementTensile strength, min, psi MPa 42 000 290Yield strength, min, psi MPa 25 000 170Elongation in 2 in. 50 mm min, % 25A254/A254M 12311. Retests11.1 If the results of the mechanical tests of any group or lot
40、 do not conform to the requirements specified in the individualspecification, retests may be made on additional tubes of double the original number from the same group or lot, each of whichshall conform to the requirements specified.12. Retreatment12.1 If the individual tubes or the tubes selected t
41、o represent any group or lot fail to conform to the test requirements, theindividual tubes or the group or lot represented may be retreated and resubmitted for test. Not more than two reheat treatmentsshall be permitted.13. Inspection13.1 The inspector representing the purchaser shall have entry at
42、all times while work on the contract of the purchaser is beingperformed, to all parts of the manufacturers works that concern the manufacture of the material ordered. The manufacturer shallafford the inspector all reasonable facilities to satisfy him that the material is being furnished in accordanc
43、e with this specification.TABLE 3 Outside Diameter RequirementsSpecified Outside Diameter, in. (mm) Variations, in. (mm)Plus or MinusUnder 316 (4.76) 0.002 (0.051)316 (4.76) through 38 (9.53) 0.003 (0.076)716 (11.1) through 58 (15.9) 0.004 (0.102)TABLE 3 Outside Diameter RequirementsSpecified Outsid
44、e Diameter, in. mm Variations, in. mmPlus or MinusUnder 316 4.75 0.002 0.050316 4.75 through 38 9.5 0.003 0.075716 11.0 through 58 16.0 0.004 0.100TABLE 4 Wall Thickness RequirementsSpecified Wall Thickness, in. (mm) Variations, in. (mm)Plus or Minus0.020 (0.51) through 0.030 (0.76) 0.003 (0.08)0.03
45、1 (0.79) through 0.049 (1.24) 0.0035 (0.09)TABLE 4 Wall Thickness RequirementsSpecified Wall Thickness, in. mm Variations, in. mmPlus or Minus0.020 0.50 through 0.030 0.75 0.003 0.080.031 0.80 through 0.049 1.25 0.0035 0.09TABLE 5 Length RequirementsSpecified Cut Length, in. (m) Variations, in. (mm)
46、18 (0.46) and under 0.03 (0.76)Over 18 (0.46) through 40 (1.02) 0.06 (1.52)Over 40 (1.02) through 80 (2.03) 0.12 (3.05)Over 80 (2.03) through 120 (3.05) 0.25 (6.35)Over 120 (3.05) +1.00 (+25.4), 0.0TABLE 5 Length RequirementsSpecified Cut Length, in. m Variations, in. mm18 0.45 and under 0.03 0.75Ov
47、er 18 0.45 through 40 1.00 0.06 1.50Over 40 1.00 through 80 2.00 0.12 3.00Over 80 2.05 through 120 3.0 0.25 6.35Over 120 3.0 +1.00 +25.0, 0.0A254/A254M 124All required tests and inspection shall be made at the place of manufacture prior to shipment, unless otherwise specified, and shallbe conducted
48、so as not to interfere unnecessarily with the operation of the works.14. Rejection14.1 Each length of tubing received from the manufacturer may be inspected by the purchaser and, if it does not meet therequirements of the specification based on the inspection and test method as outlined in the speci
49、fication, the tubing may be rejectedand the manufacturer shall be notified. Disposition of rejected tubing shall be a matter of agreement between the manufacturer andthe purchaser.14.2 Material that fails in any of the forming operations or in the process of installation and is found to be defective shall beset aside, and the manufacturer shall be notified for mutual evaluation of the materials suitability. Disposition of such ma
