1、Refrigeration Piping and Heat Transfer ComponentsASME Code for Pressure Piping, B31AN AMERICAN NATIONAL STANDARDASME B31.5-2013(Revision of ASME B31.5-2010)ASME B31.5-2013(Revision of ASME B31.5-2010)RefrigerationPiping andHeat TransferComponentsASME Code for Pressure Piping, B31AN AMERICAN NATIONAL
2、 STANDARDTwo Park Avenue New York, NY 10016 USADate of Issuance: May 31, 2013The next edition of this Code is scheduled for publication in 2016.ASME issues written replies to inquiries concerning interpretations of technical aspects of this Code.Interpretations, Code Cases, and errata are published
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11、 American Society of Mechanical EngineersTwo Park Avenue, New York, NY 10016-5990Copyright 2013 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword vCommittee Roster . viIntroduction . ixSummary of Changes xiChapter I Scope and Definitions 1500 General
12、Statements 1Chapter II Design. 8Part 1 Conditions and Criteria . 8501 Design Conditions 8502 Design Criteria 9Part 2 Design of Piping Components 24503 Criteria for Design of Piping Components . 24504 Pressure Design of Piping Components 24Part 3 Design Application of Piping Components Selection and
13、Limitations 33505 Pipe 33506 Fittings, Bends, and Intersections 34507 Valves 34508 Flanges, Blanks, Flange Facings, Gaskets, and Bolting 35Part 4 Selection and Limitations of Piping Joints . 35510 Piping Joints 35511 Welded Joints . 35512 Flanged Joints . 36513 Expanded Joints 36514 Threaded Joints
14、. 36515 Flared, Flareless, and Compression Joints 36517 Brazed and Soldered Joints 37518 Sleeve Coupled and Other Novel or Patented Joints 37Part 5 Expansion, Flexibility, Structural Attachments, Supports, and Restraints 37519 Expansion and Flexibility 37520 Design of Pipe Supporting Elements . 4652
15、1 Design Loads for Pipe Supporting Elements . 47Chapter III Materials 49523 Materials General Requirements 49524 Materials Applied to Miscellaneous Parts 54Chapter IV Dimensional Requirements 55526 Dimensional Requirements for Standard and Nonstandard PipingComponents 55Chapter V Fabrication and Ass
16、embly . 57527 Welding 57528 Brazing and Soldering . 64529 Bending Hot and Cold 65530 Forming 65531 Heat Treatment . 65535 Assembly . 68Chapter VI Examination, Inspection, and Testing 70536 Examination 70iii537 Inspection 72538 Testing . 72539 Records . 73Figures502.3.2 Stress Range Reduction Factors
17、 23504.3.1-1 Reinforcement of Branch Connections 27504.3.1-2 Extruded Outlet Header Notation . 29504.3.1-3 Mechanically Formed Tee Connections in Copper Materials 31504.5.3 Blanks 34519.4.5-1 Bends . 44519.4.5-2 Branch Connections . 45523.2.2 Reduction in Minimum Design Metal Temperature Without Imp
18、actTesting . 53527.1.2 Typical Joints With Backing Ring 58527.2.1-1 Butt Welding End Preparation . 58527.2.1-2 Internal Trimming for Butt Welding of Piping Components With InternalMisalignment . 58527.3.3-1 Fillet Weld Size . 59527.3.3-2 Welding Details for Slip-On and Socket Welding Flanges, and So
19、meAcceptable Types of Flange Attachment Welds . 60527.3.3-3 Minimum Welding Dimensions Required for Socket WeldingComponents Other Than Flanges 60527.3.5-1 Typical Welded Branch Connection Without Additional Reinforcement . 61527.3.5-2 Typical Welded Branch Connection With Additional Reinforcement .
20、 61527.3.5-3 Typical Welded Angular Branch Connection Without AdditionalReinforcement 61527.3.5-4 Some Acceptable Types of Welded Branch Attachment Details ShowingMinimum Acceptable Welds 62527.3.6-1 Acceptable Welds for Flat Plate Closures . 63527.3.6-2 Unacceptable Welds for Flat Plate Closures 64
21、Tables500.2-1 Refrigerant Safety Classifications 4500.2-2 Safety Classifications for Refrigerant Blends 6502.3.1 Maximum Allowable Stress Values, ksi 10514 Minimum Thickness of Male Threaded Components . 36519.3.1 Thermal Expansion Data, e (IP and SI) . 39519.3.2 Moduli of Elasticity, E (IP and SI)
22、40519.3.6 Flexibility Factor, k, and Stress Intensification Factor, i 42521.3.1 Minimum Sizes of Straps, Rods, and Chains for Hangers . 48523.1 Acceptable Materials Specifications . 50523.2.2 Impact Exemption Temperatures . 54526.1 Dimensional Standards 56531.2.1 Heat Treatment of Welds 66Nonmandato
23、ry AppendicesA Referenced Standards . 75B Preparation of Technical Inquiries . 78C Selecting Applicable Piping Codes . 79D Nomenclature . 81ivFOREWORDThe need for a national code for pressure pipingbecame increasingly evident from 1915 to 1925. To meetthis need, the American Engineering StandardsCom
24、mittee (later changed to American StandardsAssociation, then changed to United States of AmericaStandards Institute, and now known as the AmericanNational Standards Institute) initiated project B31 inMarch 1926, at the request of the American Society ofMechanical Engineers and with that Society the
25、soleadministrative sponsor. Because of the wide fieldinvolved, Sectional Committee B31, later changed toStandards Committee, was composed of representativesof some 40 different engineering societies, industries,government bureaus, institutes, and trade associations.After several years work, the firs
26、t edition was publishedin 1935 as an American Tentative Standard Code forPressure Piping.In order to keep the Code abreast of current develop-ments in piping design, welding, stress computations,new dimensional and material standards and specifica-tions, and increases in the severity of service cond
27、itions,revisions, supplements, and new editions of the Codewere published as follows:B31.1-1942 American Standard Code for PressurePipingB31.1a-1944 Supplement 1B31.1b-1947 Supplement 2B31.1-1951 American Standard Code for PressurePipingB31.1a-1953 Supplement 1 to B31.1-1951vB31.1-1955 American Stan
28、dard Code for PressurePipingIn 1952, a new section of the Code was published tocover Gas Transmission and Distribution PipingSystems. In 1955, after a review by B31 Executive andSectional Committees, a decision was made to developand publish other industry sections as separate codedocuments of the A
29、merican Standard Code for PressurePiping.The first edition of Refrigeration Piping was publishedas ASA B31.5-1962, superseding Section 5 of B31.1-1955.This Section was revised in 1966. Following approvalby the Sectional Committee and the sponsor, this revi-sion was approved by the United States of A
30、mericaStandards Institute on September 8, 1966, and desig-nated USAS B31.5-1966. Revision of this Section wasapproved on April 18, 1974 by the American NationalStandards Institute and designated ANSI B31.5-1974.In December 1978, the American National StandardsCommittee B31 was reorganized as the ASM
31、E Code forPressure Piping, B31 Committee under proceduresdeveloped by the American Society of MechanicalEngineers and accredited by the American NationalStandards Institute. The Code designation was alsochanged to ANSI/ASME B31.Previous editions of this Code include those of 1983,1987, 1989, 1992, 2
32、001, 2006, and 2010. In this, the2013 Edition, new additions and revisions have beenmade to the text, shown in the Summary of Changespage.This Code was approved as an American NationalStandard on February 19, 2013.ASME B31 COMMITTEECode for Pressure Piping(The following is the roster of the Committe
33、e at the time of approval of this Code.)STANDARDS COMMITTEE OFFICERSM. L. Nayyar, ChairK. C. Bodenhamer, Vice ChairN. Lobo, SecretarySTANDARDS COMMITTEE PERSONNELR. J. T. Appleby, ExxonMobil Development Co.C. Becht IV, Becht Engineering Co.A. E. Beyer, Fluor EnterprisesK. C. Bodenhamer, Enterprise P
34、roducts Co.R. M. Bojarczuk, ExxonMobil Research but where service requirements necessitateadded quality and more extensive nondestructive exam-ination, these are to be specified in the engineeringdesign and any revision thereto, and when so specified,the Code requires that they be accomplished.500.1
35、 ScopeRules for this Code Section have been developed con-sidering the needs for applications that include pipingand heat transfer components for refrigerants and sec-ondary coolants.500.1.1 This Code prescribes requirements for thematerials, design, fabrication, assembly, erection, test,and inspect
36、ion of refrigerant, heat transfer components,and secondary coolant piping for temperatures as lowas 320F (196C), whether erected on the premises orfactory assembled, except as specifically excluded in thefollowing paragraphs.500.1.3 This Code shall not apply to any of thefollowing:(a) any self-conta
37、ined or unit systems subject to therequirements of Underwriters Laboratories or othernationally recognized testing laboratory1(b) water piping, other than where water is used asa secondary coolant or refrigerant(c) piping designed for external or internal gage pres-sure not exceeding 15 psi (105 kPa
38、) regardless of size(d) pressure vessels, compressors, or pumps, but doesinclude all connecting refrigerant and secondary coolantpiping starting at the first joint adjacent to suchapparatus500.2 DefinitionsFor convenience in reference, some of the more com-mon terms relating to piping are defined in
39、 thissubdivision.Most welding definitions were taken from the AWSWelding Handbook, Volume 1, 7th Edition. Heat treat-ment terms were taken from ASM Metals HandbookProperties and Selection of Materials, Volume 1, 8thEdition.arcwelding: a group of welding processes wherein coales-cence is produced by
40、heating with an electric arc(s),with or without the application of pressure and with orwithout the use of filler metal.automatic welding: welding with equipment that per-forms the entire welding operation without constantobservation and adjustment of the controls by an opera-tor. The equipment may o
41、r may not perform the loadingand unloading of the work.backing ring: backing in the form of a ring generally usedin the welding of piping.base metal: the metal to be welded, soldered, brazed,or cut.brazing: a joining process that produces coalescence ofmaterials by heating them in the presence of a
42、fillermetal having a liquidus above 840F (450C) but belowthe solidus of the base metals. Heating may be providedby a variety of processes. The filler metal distributesitself between the closely fitted surfaces of the joint bycapillary action. Brazing differs from soldering in thatASME B31.5-2013sold
43、ering filler metals have a liquidus below 840F(450C).brine: a secondary coolant that is a solution of a salt andwater.butt joint: an assembly of two members lying approxi-mately in the same pressor: a specific machine, with or without accesso-ries, for compressing a given refrigerant vapor.condenser
44、: that part of a refrigerating system designedto liquefy refrigerant vapor by the removal of heat.condenser coil: a condenser constructed of pipe or tube,not enclosed in a pressure vessel.design pressure: see section 501.engineering design: the detailed design developed fromprocess requirements and
45、conforming to Code require-ments, including all necessary drawings and specifica-tions, governing a piping installation.equipment connection: an integral part of such equipmentas pressure vessels, heat exchangers, and pumps,designed for attachment to pipe or piping components.evaporator: that part o
46、f a refrigerating system designedto vaporize liquid refrigerant to produce refrigeration.evaporatorcoil: an evaporator constructed of pipe or tube,not enclosed in a pressure vessel.face of weld: the exposed surface of a weld on the sidefrom which the welding was done.filler metal: metal to be added
47、in making a welded,brazed, or soldered joint.fillet weld: a weld of approximately triangular cross-section joining two surfaces approximately at rightangles to each other in a lap joint, tee joint, corner joint,or socket joint.fusion: see weld.gas metal-arc welding (GMAW): an arc welding processwher
48、ein coalescence is produced by heating with an arcbetween a continuous filler metal (consumable) elec-trode and the work. Shielding is obtained entirely froman externally supplied gas or gas mixture. (Some meth-ods of this process are called MIG or CO2welding.)gas tungsten-arc welding (GTAW): an arc
49、 welding processwherein coalescence is produced by heating with an arcbetween a single tungsten (nonconsumable) electrodeand the work. Shielding is obtained from a gas or gasmixture. Pressure may or may not be used and fillermetal may or may not be used. (This process is some-times called TIG welding.)gas welding: a group of welding processes whereincoalescence is produced by heating with a gas flame orflames, with or without the application of pressure, andwith or without the use of filler metal.2groove weld: a weld made in the groove between twomembers to be
