1、BSI Standards PublicationBS ISO 7121:2016Steel ball valves for general-purpose industrial applicationsBS ISO 7121:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 7121:2016. It supersedes BS ISO 7121:2006 which is withdrawn.The UK participation in its prepa
2、ration was entrusted to Technical Committee PSE/18/1, Industrial valves, steam traps, actuators and safety devices against excessive pressure - Valves - Basic standards.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport
3、 to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2016. Published by BSI Standards Limited 2016ISBN 978 0 580 90035 8 ICS 23.060.20 Compliance with a British Standard cannot confer immunity from legal obligati
4、ons.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 April 2016.Amendments issued since publicationDate T e x t a f f e c t e dBS ISO 7121:2016 ISO 2016Steel ball valves for general-purpose industrial applicationsRobinets en acier tournant
5、sphrique pour les applications industrielles gnralesINTERNATIONAL STANDARDISO7121Third edition2016-04-15Reference numberISO 7121:2016(E)BS ISO 7121:2016ISO 7121:2016(E)ii ISO 2016 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in SwitzerlandAll rights reserved. Unless otherwise
6、specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
7、or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 7121:2016ISO 7121:2016(E)Foreword vIntroduction vi1 Scope . 12 Normative references 13 Term
8、s and definitions . 24 Pressure/temperature ratings 34.1 Valve rating . 34.2 Shell rating 34.3 Seat and seal rating . 35 Design 45.1 Flow passageway 45.2 Body 55.2.1 Body wall thickness . 55.2.2 Flanged ends 85.2.3 Butt-welding ends. 85.2.4 Socket welding ends . 85.2.5 Threaded ends . 95.2.6 Body op
9、enings 95.2.7 Anti-static design . 95.2.8 Anti-blow-out stem .105.2.9 Ball-stem construction 105.2.10 Ball construction .105.2.11 Operating means .105.2.12 Glands . 115.2.13 End flange facing interruptions . 115.2.14 Shell joints 125.2.15 Packing gland bolting 136 Materials 136.1 Shell . 136.2 Shell
10、 material repair 146.3 Trim . 146.4 Identification plate . 146.5 Bolting . 146.6 Seals . 146.7 Threaded plugs 147 Marking .147.1 Legibility 147.2 Body marking 147.3 Ring joint marking 157.4 Identification plate . 157.5 Special marking for unidirectional valves 158 Testing and inspection 168.1 Pressu
11、re tests 168.1.1 General. 168.1.2 Shell test . 168.1.3 Closure tightness test 168.2 Inspection . 178.3 Examination 178.4 Supplementary examination 189 Preparation for despatch 18 ISO 2016 All rights reserved iiiContents PageBS ISO 7121:2016ISO 7121:2016(E)Annex A (informative) Information to be spec
12、ified by the purchaser 19Annex B (informative) Identification of valve parts 20Bibliography .22iv ISO 2016 All rights reservedBS ISO 7121:2016ISO 7121:2016(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). T
13、he work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-go
14、vernmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described
15、in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the
16、possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO li
17、st of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well
18、 as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.The committee responsible for this document is ISO/TC 153, Valves.This third edition cancels and replaces the second edi
19、tion (ISO 7121:2006), which has been technically revised with the following changes: in the scope DN 600, NPS 20 and 24, Class 800 and a note on the applicability of this Class were added; the normative references were updated; definitions for DN, NPS, PN and Class were added; a line for DN 600 was
20、added in Table 2; a line for DN 600 and a column for Class 800 were added in Table 3; a column for DN 600 was added in Table 4; a column for Class 800 was added in Table 6; in Tables 7 and 8, DN is up to 600; in 5.2.12.3, vertically split glands are not allowed anymore; Annex A was updated according
21、ly; 8.2.2 on site inspection was deleted; Annex A was updated accordingly. ISO 2016 All rights reserved vBS ISO 7121:2016ISO 7121:2016(E)IntroductionThe purpose of this International Standard is the establishment, in ISO format, of basic requirements and practices for flanged, butt-welding, socket w
22、elding and threaded-end steel ball valves having flow passageways identified as full bore, reduced bore and double reduced bore, suitable for general purpose applications. Flanged end Class designated valves have flanges in accordance with ASME B16.5. Flanged end PN designated valves have flanges in
23、 accordance with EN 1092-1. Valves with ends that are threaded can have threads to either ISO 7-1 or ASME B1.20.1.vi ISO 2016 All rights reservedBS ISO 7121:2016Steel ball valves for general-purpose industrial applications1 ScopeThis International Standard specifies the requirements for a series of
24、steel ball valves suitable for general-purpose industrial applications.It covers valves of the nominal sizes DN 8, 10, 15, 20, 25, 32, 40, 50, 65, 80, 100, 150, 200, 250, 300, 350, 400, 450, 500, and 600 (NPS 1/4, 3/8, 1/2, 3/4, 1, 11/4, 11/2, 2, 21/2, 3, 4, 6, 8, 10, 12, 14, 16, 18, 20 and 24),and
25、is applicable to the following pressure designations: PN 10; 16; 25; 40; 63; 100; Class 150; 300; 600; 800; 900.NOTE Valve characteristics are not necessarily available in all nominal sizes for all pressure designations. For example, Class 800 applies only for valves with threaded end and socket wel
26、d ends up to DN 65 (NPS 21/2) and Class 900 applies only for reduced bore body seat openings.It includes provisions for valve characteristics as follows: flanged and butt-welded ends in sizes 15 DN 600 (1/2 NPS 24); socket welding ends in sizes 8 DN 100 (1/4 NPS 4); threaded ends in sizes 8 DN 50 (1
27、/4 NPS 2); body seat openings designated as full bore, reduced bore and double reduced bore; materials; testing and inspection.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated referenc
28、es, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 7-1, Pipe threads where pressure-tight joints are made on the threads Part 1: Dimensions, tolerances and designationISO 7-2, Pipe threads where pressure-ti
29、ght joints are made on the threads Part 2: Verification by means of limit gaugesISO 228-1, Pipe threads where pressure-tight joints are not made on the threads Part 1: Dimensions, tolerances and designationISO 228-2, Pipe threads where pressure-tight joints are not made on the threads Part 2: Verifi
30、cation by means of limit gaugesISO 261, ISO general purpose metric screw threads General planINTERNATIONAL STANDARD ISO 7121:2016(E) ISO 2016 All rights reserved 1BS ISO 7121:2016ISO 7121:2016(E)ISO 965-2, ISO general purpose metric screw threads Tolerances Part 2: Limits of sizes for general purpos
31、e external and internal screw threads Medium qualityISO 4032, Hexagon regular nuts (style 1) Product grades A and BISO 4033, Hexagon high nuts (style 2) Product grades A and BISO 4034, Hexagon regular nuts (style 1) Product grade CISO 5208, Industrial valves Pressure testing of metallic valvesISO 52
32、09, General purpose industrial valves MarkingISO 5752, Metal valves for use in flanged pipe systems Face-to-face and centre-to-face dimensionsEN 1092-1, Flanges and their joints Circular flanges for pipes, valves, fittings and accessories, PN designated Part 1: Steel flangesEN 1515-1:1999, Flanges a
33、nd their joints Bolting Part 1: Selection of boltingEN 12982, Industrial valves End-to-end and centre-to-end dimensions for butt welding end valvesASME B1.1, Unified Inch Screw Threads, (UN and UNR Thread Form)ASME B1.20.1, Pipe Threads, General Purpose, InchASME B16.5, Pipe Flanges and Flanged Fitt
34、ings: NPS 1/2 through NPS 24 Metric/Inch StandardASME B16.10, Face-to-Face and End-to-End Dimensions of ValvesASME B16.34:2013, Valves Flanged, Threaded and Welding EndASME B18.2.2, Nuts for General Applications: Machine Screw Nuts, Hex, Square, Hex Flange, and Coupling Nuts (Inch Series)MSS-SP-55,1
35、)Quality Standard for Steel Castings for Valves, Flanges and Fittings and Other Piping Components Visual Method for Evaluation of Surface Irregularities3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1DN or NPSalphanumeric designation of size tha
36、t is common for components used in a piping system, used for reference purposes, comprising the letters DN or NPS followed by a dimensionless number indirectly related to the physical size of the bore or outside diameter of the end connectionsNote 1 to entry: The number following DN or NPS does not
37、represent a measurable value and is not used for calculation purposes except where specified in a product standard.Note 2 to entry: See ISO 6708 and ASME B16.34.1) Manufacturers Standardization Society standard.2 ISO 2016 All rights reservedBS ISO 7121:2016ISO 7121:2016(E)3.2PN or Classalphanumeric
38、designation for pressure-temperature rating that is common for components used in a piping system, used for reference purposes, comprising the letters “PN or Class” followed by a dimensionless number indirectly related to the pressure retaining capability as a function of temperature of the componen
39、tNote 1 to entry: The number following PN or Class does not represent a measurable value and is not used for calculation purposes except where specified in a product standard. There is no definitive correlation that links PN designations to Class designations.Note 2 to entry: See ISO 7268, EN 1333 a
40、nd ASME B16.34.3.3service pressure/temperature ratinglesser of the shell or seat pressure/temperature rating3.4anti-static designdesign that provides for electrical continuity between the body, ball and stem of the valve3.5anti-blow-out designdesign that ensures the valve stem cannot be ejected from
41、 the body in the event of the gland being removed while the valve is under pressure4 Pressure/temperature ratings4.1 Valve ratingThe service pressure/temperature rating applicable to valves specified in this International Standard shall be the littlest of the shell rating (4.2) or the seat rating (4
42、.3).4.2 Shell rating4.2.1 The pressure/temperature ratings applicable to the valve pressure containing shell (the pressure boundary elements, e.g. body, body cap, trunnion cap, cover, body inserts) shall be in accordance with that specified in the pressure/temperature tables of either ASME B16.34, S
43、tandard Class, for Class designated valves, or EN 1092-1 for PN designated valves.4.2.2 The temperature for a corresponding shell pressure rating is the maximum temperature that is permitted for the pressure-containing shell of the valve. In general, this maximum temperature is that of the contained
44、 fluid. The use of a pressure rating corresponding to a temperature other than that of the contained fluid is the responsibility of the user. For temperatures below, the lowest temperature listed in the pressure/temperature tables (see 4.2.1), the service pressure shall be no greater than the pressu
45、re for the lowest listed temperature. Consideration should be given to the loss of ductility and impact strength of many materials at low temperature.4.3 Seat and seal rating4.3.1 Non-metallic elements, for example, seat, seals or stem seals, can impose restrictions on the applied pressure/temperatu
46、re rating. Any such restriction shall be shown on the valve identification plate in accordance with 7.4.4.3.2 The design shall be such that, when either polytetrafluoroethylene (PTFE) or reinforced PTFE is used for seats, the minimum valve pressure/temperature rating shall be as specified in Table 1
47、. Designs ISO 2016 All rights reserved 3BS ISO 7121:2016ISO 7121:2016(E)using these seating materials having pressure/temperature ratings less than those shown in Table 1 are not in compliance with this International Standard.4.3.3 Seat ratings for other seat materials shall be according to the manu
48、facturers standard. However, the assigned valve service pressure/temperature rating shall not exceed that of the valve shell.Table 1 Minimum seat pressure/temperature ratingTemperaturebCPTFE seatsabarcReinforced PTFE seatsabarcFloating ball Trunnion Floating ball TrunnionDN 50 50 100 DN 50 DN 50 50
49、100 DN 50NPS 2 2 4 NPS 2 NPS 2 2 4 NPS 229 to 38 69,0 51,0 19,7 51,0 75,9 51,0 19,7 51,050 63,6 47,1 18,2 47,1 70,4 47, 8 18,4 47, 875 53,3 39,2 15,2 39,2 59,9 40,4 15,6 40,4100 43,0 31,3 12,1 31,3 49,4 33,1 12,8 33,1125 32,7 23,3 9,1 23,3 38,9 25,8 10,0 25,8150 22,4 15,4 6,1 15,4 28,3 18,4 7, 2 18,4175 12,1 7, 5 3,0 7, 5 17, 8 11,1 4,4 11,1200 7, 3 3,7 1,6 3,7205 5,2 2,3 1,0 2,3For a given PN or Class designation, the assigned valve pressure
