1、Guide for theEvaluation of HotGas, Hot GasExtrusion, andHeated Tool ButtThermoplasticWeldsAWS G1.10M:2001An American National Standard550 N.W. LeJeune Road, Miami, Florida 33126AWS G1.10M:2001An American National StandardApproved byAmerican National Standards InstituteFebruary 21, 2001Guide for the
2、Evaluation ofHot Gas, Hot Gas Extrusion,and Heated Tool ButtThermoplastic WeldsPrepared byAWS G1 Committee on Joining Plastics and CompositesUnder the Direction ofAWS Technical Activities CommitteeApproved byAWS Board of DirectorsAbstractThis standard lists and describes defects in hot gas, hot gas
3、extrusion, and heated tool butt welded joints in thermoplastics.Its intent is to make possible a generally valid evaluation giving consideration to graded quality requirements. This stan-dard encompasses the classification, requirements, testing, evaluation, and acceptance of the welds. Details in r
4、ecordingengineering data are described. Tables illustrating cracks, voids, solid inclusions, lack of fusion, defects of shape, andother defects in thermoplastic welds are included. Defect features with descriptions and illustrations are compiled intotables to aid in the evaluation of welds.Key Words
5、Hot gas welding, thermoplastics, heated tool butt welding, joints, evaluation, testing, hot gas extrusionStatement on Use of AWS American National StandardsAll standards (codes, specifications, recommended practices, methods, classifications, and guides) of the AmericanWelding Society are voluntary
6、consensus standards that have been developed in accordance with the rules of the AmericanNational Standards Institute. When AWS standards are either incorporated in, or made part of, documents that areincluded in federal or state laws and regulations, or the regulations of other governmental bodies,
7、 their provisions carrythe full legal authority of the statute. In such cases, any changes in those AWS standards must be approved by thegovernmental body having statutory jurisdiction before they can become a part of those laws and regulations. In allcases, these standards carry the full legal auth
8、ority of the contract or other document that invokes the AWS standards.Where this contractual relationship exists, changes in or deviations from requirements of an AWS standard must be byagreement between the contracting parties.International Standard Book Number: 0-87171-615-1American Welding Socie
9、ty, 550 N.W. LeJeune Road, Miami, FL 33126 2001 by American Welding Society. All rights reservedPrinted in the United States of AmericaAWS American National Standards are developed through a consensus standards development process that bringstogether volunteers representing varied viewpoints and int
10、erests to achieve consensus. While AWS administers the processand establishes rules to promote fairness in the development of consensus, it does not independently test, evaluate, orverify the accuracy of any information or the soundness of any judgments contained in its standards.AWS disclaims liabi
11、lity for any injury to persons or to property, or other damages of any nature whatsoever, whether spe-cial, indirect, consequential or compensatory, directly or indirectly resulting from the publication, use of, or reliance on thisstandard. AWS also makes no guaranty or warranty as to the accuracy o
12、r completeness of any information published herein.In issuing and making this standard available, AWS is not undertaking to render professional or other services for or onbehalf of any person or entity. Nor is AWS undertaking to perform any duty owed by any person or entity to someoneelse. Anyone us
13、ing these documents should rely on his or her own independent judgment or, as appropriate, seek the adviceof a competent professional in determining the exercise of reasonable care in any given circumstances.This standard may be superseded by the issuance of new editions. Users should ensure that th
14、ey have the latest edition.Publication of this standard does not authorize infringement of any patent. AWS disclaims liability for the infringementof any patent resulting from the use or reliance on this standard.Finally, AWS does not monitor, police, or enforce compliance with this standard, nor do
15、es it have the power to do so.Official interpretations of any of the technical requirements of this standard may be obtained by sending a request, in writ-ing, to the Managing Director Technical Services, American Welding Society, 550 N.W. LeJeune Road, Miami, FL 33126(see Annex C). With regard to t
16、echnical inquiries made concerning AWS standards, oral opinions on AWS standards maybe rendered. However, such opinions represent only the personal opinions of the particular individuals giving them. Theseindividuals do not speak on behalf of AWS, nor do these oral opinions constitute official or un
17、official opinions or interpre-tations of AWS. In addition, oral opinions are informal and should not be used as a substitute for an official interpretation.This standard is subject to revision at any time by the AWS G1 Committee on Joining of Plastics and Composites. It mustbe reviewed every five ye
18、ars and if not revised, it must be either reapproved or withdrawn. Comments (recommendations,additions, or deletions) and any pertinent data that may be of use in improving this standard are required and should be ad-dressed to AWS Headquarters. Such comments will receive careful consideration by th
19、e AWS G1 Committee on Joiningof Plastics and Composites and the author of the comments will be informed of the Committees response to the com-ments. Guests are invited to attend all meetings of the AWS G1 Committee on Joining of Plastics and Composites to ex-press their comments verbally. Procedures
20、 for appeal of an adverse decision concerning all such comments are provided inthe Rules of Operation of the Technical Activities Committee. A copy of these Rules can be obtained from the AmericanWelding Society, 550 N.W. LeJeune Road, Miami, FL 33126.Photocopy RightsAuthorization to photocopy items
21、 for internal, personal, or educational classroom use only, or the internal, personal, oreducational classroom use only of specific clients, is granted by the American Welding Society (AWS) provided that theappropriate fee is paid to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01
22、923, Tel: 978-750-8400;online: http:/.iii*AdvisorPersonnelAWS G1 Committee on Joining of Plastics and CompositesJ. L. Frantz, Chair Branson Ultrasonics Corp.W. J. McMaster, Vice Chair HoneywellJ. L. Gayler, Secretary American Welding Society*A. Benatar The Ohio State University*F. Dibble Crest Ultra
23、sonicsK. M. Dolan GE Plastics*D. Grewell Branson Ultrasonics Corp.*R. A. Grimm Edison Welding InstituteB. E. Gourley Sonics features, descriptions, evaluation, was used extensively in the creation of this standard.Comments and suggestions for the improvement of this standard are welcome. They should
24、 be sent to the Secretary,AWS G1 Committee on Joining of Plastics and Composites, American Welding Society, 550 N.W. LeJeune Road,Miami, FL 33126.Official interpretations of any of the technical requirements of this standard may be obtained by sending a request, inwriting, to the Managing Director,
25、Technical Services Division, American Welding Society (see Annex C). A formalreply will be issued after it has been reviewed by the appropriate personnel following established procedures.viiTable of ContentsPage No.Personnel iiiForeword.v1. Scope, Purpose, and Range of Application .12. Referenced Do
26、cuments13. Definitions .24. Evaluation Groups .24.1 Classification.24.2 Criteria for Establishment .25. Requirements for Welded Joints25.1 Quality Features for Classification of the Weld (Annexes VII through IX) .26. Details In Engineering Data.27. Testing and Evaluation.37.1 Evaluation37.2 Reworkin
27、g Defective Welded Joints .37.3 Overlapping Defects38. Acceptance.3AnnexesMandatory InformationAnnex ICracks .5Annex IIVoids 7Annex IIISolid Inclusions9Annex IVLack of Fusion11Annex VDefects of Shape 13Annex VIOther Defects15Annex VIIDescription of Evaluation Groups for Hot Gas Fan and Speed Welds.1
28、7Annex VIIIDescription of Evaluation Groups for Hot Gas Extrusion Welds21Annex IXDescription of Evaluation Groups for Heated Tool Butt Welds .25AnnexesNonmandatory InformationAnnex AOther Documents.29Annex BDocument Sources .31Annex CGuidelines for Preparation of Technical Inquiries for AWS Technica
29、l Committees .33AWS List of Documents on Plastics Welding35AWS G1.10M:200111. Scope, Purpose, and Range of Application1.1 These guidelines list and describe defects in weldedjoints in thermoplastic materials. The objective is tomake possible a generally valid evaluation giving consid-eration to grad
30、ed quality requirements.1.2 By classification into one of the evaluation groups in4.1, specific defects can be excluded or kept within limitswhen welded joints are produced.1.3 The application of these guidelines and the measuresthrough which they can be met may be included in con-tractual specifica
31、tion or form part of the generally recog-nized specifications.1.4 Welding Processes. Defects produced by the follow-ing welding processes are addressed. This guide appliesto the following processes:Abbreviation AnnexHot gas fan (rod) welding WF VIIHot gas speed welding WZ VIIHot gas extrusion weldin
32、g WE VIIIHeated tool butt welding HS IX1.5 Materials. These guidelines apply to welded jointson components and systems made from the engineeringthermoplastics listed below:Abbreviation Material DescriptionECTFE Ethylene chlorotrifluoroethyleneETFE Ethylene tetrafluoroethyleneFEP Fluorinated ethylene
33、-propyleneMFA PerfluoromethylvinyletherM PTFE PFA modified PTFEPE-HD High density polyethylene (rigid PE)PFA PerfluoroalkoxyPP-B Polypropylene block copolymerPP-H Polypropylene homopolymerPP-R Polypropylene random copolymerPTFE PolytetrafluoroethylenePVC-C Chlorinated polyvinyl chlorideAbbreviation
34、Material DescriptionPVC-HI High-impact polyvinyl chloridePVC-U Unplasticized polyvinyl chloride (rigid PVC)PVDF Polyvinylidene fluoridePVDF/HFP Polyvinylidene fluoride/hexafluoropropylene1.6 The use of these guidelines for welding other thermo-plastic materials must be agreed upon between the cus-to
35、mer and the fabricator.1.7 This standard makes use of the International Systemof Units (SI).1.8 Safety. The activities described in this document maybring the user of this standard in contact with processesand materials that may be hazardous to the users health.Safety precautions mandated by OSHA an
36、d recommen-dations for material handling in MSDS sheets should beobserved. The fabricators operating manual and safetyinstructions should always be carefully studied and com-plied with when operating equipment.Note: This standard may involve hazardous materials, op-erations, and equipment. This stan
37、dard does not purport toaddress all of the safety problems associated with its use. Itis the responsibility of the user to establish appropriatesafety and health practices. The user should determine theapplicability of any regulatory limitations prior to use.2. Referenced DocumentsReference should b
38、e made to the latest edition of thefollowing documents:ASTM C 904 Standard Terminology Relating to Chemical-Resistant Nonmetallic Materials11. ASTM documents are available from the American Societyfor Testing and Materials, 100 Barr Harbor Drive, West Consho-hocken, PA 19428-2959.Guide for the Evalu
39、ation of Hot Gas, Hot Gas Extrusion, and Heated Tool Butt Thermoplastic WeldsAWS G1.10M:20012ASTM D 5162 Test Method B: Standard Practice forDiscontinuity (Holiday) Testing of Non-conductive Protective Coating on MetallicSubstrates1AWS A3.0 Standard Welding Terms and Definitions23. DefinitionsThe te
40、rms used in this specification are defined inASTM C 904, Terminology Relating to Chemical-ResistantNonmetallic Materials, and AWS A3.0, Standard WeldingTerms and Definitions. Exceptions, within the context ofthis standard, are listed below with their definitions.bead-stop crack. A crack occurring at
41、 the restarting of aweld due to the thermal characteristics of an over-stressed weld rod. Thermoplastic materials exhibitthermal characteristics that contribute to this condition.shrinkage groove. Insufficiency of material on the lat-eral edges of the weld due to the high thermal shrink-age or expan
42、sion characteristics of thermoplastics;this resembles an undercut or underfill weld.spark testing. An electronic test to locate discontinuitiesin a nonconductive material backed by a conductivesubstrate (Reference ASTM D 5162, Test Method B).void. An unfilled space within a weld.4. Evaluation Groups
43、4.1 Classification. Specific requirements are establishedfor the intended service of a component, particularly re-garding the quality of the welded joints. The followingclassification is used as a basis, so that the fabricator andinspector know the extent of the measures required forquality control
44、with regard to welding.Evaluation Group Requirement LevelI High requirements for reliabilityand/or intended service.II Medium requirements for reliabilityand/or intended service.III Low requirements for reliabilityand/or intended service.2. AWS documents are available from Global Engineering Doc-ume
45、nts, An Information Handling Services Group Company, 15Inverness Way East, Englewood, Colorado 80112-5776. Tele-phones (800) 854-7179, (303) 397-7956; FAX (303) 397-2740;Internet: .The requirements to be established for the welded jointson a component should in each case be restricted to thosewhich
46、are necessary and appropriate for the application.4.2 Criteria for Establishment. In the establishment ofthe evaluation groups, the following factors, among others,should be taken into account:(1) level and type of stress (for example static, dynamic)(2) thermoplastic material (for example viscous,
47、brittle)(3) operating conditions (for example stationary,mobile, environmental)(4) production conditions (for example workshop,construction site)(5) potential hazards (for example hazardous gasesand/or hazardous fluids)5. Requirements for Welded Joints5.1 Quality Features for Classification of the W
48、eld(Annexes VII through IX). The requirements for classi-fying a welded joint within a particular quality grade areestablished in the evaluation groups.In the majority of cases, requirements are establishedfor the joint listing specific features, and describing themwith reference to the internal and
49、 external state of thejoint. By using Annexes VII through IX, it is possible tospecify requirements for the quality of welding. Usingindividual features, i.e. through the type and extent of thedefects, an evaluation of welded joints can then be under-taken (for example, as part of the acceptance procedurefor the component).5.1.1 Requirements for Characteristics. This coversadditional data such as:(1) deformation resistance (for example welding factor)(2) ductility (for example bending angle to cracking)(3) resistance to chemical attack (fo
