ASME_B31P-2017.pdf

AN AM E R IC AN NAT IO NAL STANDARDASME B31P-2017Standard Heat Treatments for Fabrication ProcessesASME Code for Pressure Piping,B31ASME B31P-2017Standard HeatTreatments forFabricationProcessesASME Code for Pressure Piping,B31xDate of Issuance:May 15,2018The next edition of this Standard is scheduled for publication in 2021.ASME issues written replies to inquiries concerning interpretations of technical aspects of this Standard.Interpretations arepublished under http:/go.asme.org/Interpretations.Periodically certain actions of the ASME B31 Committees may bepublished as Cases.Cases are published on the ASME website under the Committee Pages at http:/go.asme.org/B31committee as they are issued.Errata to codes and standards may be posted on the ASME website under the Committee Pages to provide corrections toincorrectlypublisheditems,ortocorrecttypographicalorgrammaticalerrorsincodesandstandards.Sucherratashallbeusedon the date posted.The B31 Committee Pages can be found at http:/go.asme.org/B31committee.The associated B31 Committee Pages for eachcode and standard can be accessed from this main page.There is an option available to automatically receive an e-mailnotification when errata are posted to a particular code or standard.This option can be found on the appropriateCommittee Page after selecting“Errata”in the“Publication Information”section.ASME is the registered trademark of The American Society of Mechanical Engineers.ThiscodeorstandardwasdevelopedunderproceduresaccreditedasmeetingthecriteriaforAmericanNationalStandards.TheStandardsCommitteethatapprovedthecodeorstandardwasbalancedtoassurethatindividualsfromcompetentandconcernedinterestshavehadanopportunityto participate.The proposed codeorstandardwasmadeavailable forpublic reviewandcommentthatprovidesanopportunityfor additional public input from industry,academia,regulatory agencies,and the public-at-large.ASME does not“approve,”“rate,”or“endorse”any item,construction,proprietary device,or activity.ASME does not take any position with respect to the validity of any patent rights asserted in connection with any items mentioned in thisdocument,anddoesnotundertaketoinsureanyoneutilizingastandardagainstliabilityforinfringementofanyapplicableletterspatent,norassumeanysuchliability.Usersofacodeorstandardareexpresslyadvisedthatdeterminationofthevalidityofanysuchpatentrights,andtherisk of infringement of such rights,is entirely their own responsibility.Participation by federal agency representative(s)or person(s)affiliated with industry is not to be interpreted as government or industryendorsement of this code or standard.ASME accepts responsibility for only those interpretations of this document issued in accordance with the established ASME proceduresand policies,which precludes the issuance of interpretations by individuals.No part of this document may be reproduced in any form,in an electronic retrieval system or otherwise,without the prior written permission of the publisher.The American Society of Mechanical EngineersTwo Park Avenue,New York,NY 10016-5990Copyright 2018 byTHE AMERICAN SOCIETY OF MECHANICAL ENGINEERSAll rights reservedPrinted in U.S.A.CONTENTSForeword.vCommittee Roster.viCorrespondence With the B31 Committee.viii1Introduction.12Glossary.13Temperature Measurement.14Temperature Control.25Welding Preheat.36Postweld Heat Treatment(PWHT).47Postforming and Material Heat Treatments.68Alternatives and Exemptions to Preheat and PWHT Requirements.9Nonmandatory AppendicesARecommendations for the Proper Use of Thermocouples.10BRecommendationsforControlofNarrowTemperatureRangeHeatTreatments:LocalHeat-TreatmentMethods.11CBranch Connection Examples.26DTemper Bead Method Alternative to PWHT.28EFracture Mechanics Alternative to PWHT.29FiguresB-3.1-1Definition of Terms for Local Circumferential Band Heating of Pipe Weld.12B-3.1-2DefinitionofTermsforLocalCircumferentialBandHeatingofBranchConnectiontoPipeAttachmentWeld.13B-5.2-1LocationofThermocouples(MonitoringandControl)forPipeSizesLessThanNPS6(150DN)andOneControl Zone.15B-5.2-2Location of Thermocouples(Monitoring and Control)for Pipe Sizes NPS 6(DN 150)Up to andIncluding NPS 12(DN 300)and Two Control Zones.16B-5.2-3Location of Thermocouples(Monitoring and Control)for Pipe Sizes NPS 14(DN 350)Up to andIncluding NPS 30(DN 750)and Four Control Zones.17B-5.2-4Location of Monitoring Thermocouples for Branch Nozzle or Attachment Welds.18B-5.3-1ExampleofOneApproachWhentheHeatedBandFromaWeldRequiringPWHTIntersectsaWeldNotRequiring PWHT.20C-1Typical Branch Attachment Details That May Be Used to Calculate Control Thickness.26C-2TypicalIntegrallyReinforcedOutletFittingBranchConnectionDetailsThatMayBeUsedtoCalculateControl Thickness.27Tables5.1-1Preheat Temperature.36.1.1-1Postweld Heat Treatment.5iii6.1.1-2Alternate Postweld Heat Treatment Requirements for Carbon and Low-Alloy Steels,P-Nos.1 and 366.1.1-3Exemptions to Mandatory Postweld Heat Treatment.76.2-1Approximate Lower Transformation Temperatures.9B-5.1-1Require