1、BRITISH STANDARD BS EN ISO 15330:1999 Fasteners Preloading test for the detection of hydrogen embrittlement Parallel bearing surface method The European Standard EN ISO 15330:1999 has the status of a British Standard ICS 21.060.01BS EN ISO 15330:1999 This British Standard, having been prepared under
2、 the directionof the Engineering SectorCommittee, was publishedunder the authority ofthe Standards Committee andcomes into effect on 15 November 1999 BSI 04-2000 ISBN 0 580 35013 4 National foreword This British Standard is the English language version of ENISO15330:1999. It is identical with ISO 15
3、330:1999. The UK participation in its preparation was entrusted by Technical Committee FME/9, Bolts, nuts and accessories, to Subcommittee FME/9/1, Mechanical properties of fasteners, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/Euro
4、pean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary
5、. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding European publications. The British Standards which implement international or European publications refer
6、red to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a c
7、ontract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theEN ISO title page, page 2
8、, the ISO title page, pages ii to iv, pages 1 to 8 anda back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBS EN I
9、SO 15330:1999 BSI 04-2000 i Contents Page National foreword Inside front cover Foreword 2 Foreword iii Text of ISO 15330 1ii blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 15330 September 1999 ICS 21.060.10 English version Fasteners Preloading test for the detection of hydrogen embrit
10、tlement Parallel bearing surface method (ISO 15330:1999) Elments de fixation Essai de prcharge pour la dtection de la fragilisation par lhydrogne Mthode des plaques parallles (ISO 15330:1999) Verbindungselemente Verspannungsversuch zur Entdeckung von Wasserstoffversprdung Verfahren mit parallelen Au
11、flageflchen (ISO 15330:1999) This European Standard was approved by CEN on 21 July 1999. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lis
12、ts and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the respo
13、nsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Neth
14、erlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1999 CEN All rights of exploitation in any form and by any means
15、 reserved worldwide for CEN national Members. Ref. No. EN ISO 15330:1999 EEN ISO 15330:1999 BSI 04-2000 2 Foreword The text of the International Standard ISO15330:1999 has been prepared by Technical Committee ISO/TC 2 “Fasteners” in collaboration with Technical Committee CEN/TC 185 “Threaded and non
16、-threaded mechanical fasteners and accessories”, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by March 2000, and conflicting national standards shall be wi
17、thdrawn at the latest by March 2000. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, CzechRepublic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy,
18、Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of the International Standard ISO15330:1999 was approved by CEN as a European Standard without any modification. NOTENormative references to International Standards are listed in
19、 Annex ZA (normative).EN ISO 15330:1999 ii BSI 04-2000 Contents Page Foreword iii Introduction 1 1 Scope 1 2 Normative references 1 3 Terms and definitions 1 4 Principle 2 5 Test apparatus 2 6 Sampling 4 7 Test procedure 5 8 Test evaluation 6 9 Test report 6 Bibliography 7 Annex ZA (normative) Norma
20、tive references to international publicationswiththeir relevant European publications 8 Figure 1 Test devices for metric bolts, screws and stud 2 Figure 2 Example for a test device for bolts and screws with noflatbearingsurface 3 Figure 3 Test apparatus for thread rolling screws, self-tapping screws
21、 or self-drilling screws 4 Figure 4 Test apparatus for conical spring washers 4EN ISO 15330:1999 BSI 04-2000 iii Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards
22、 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-governmental, in liaison with ISO, also take p
23、art in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. Draft International Standards adopted by th
24、e technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. International Standard ISO 15330 was prepared by Technical Committee ISO/TC 2, Fasteners, Subcommittee SC 1, Mechani
25、cal properties of fasteners.iv blankEN ISO 15330:1999 BSI 04-2000 1 Introduction When atomic hydrogen enters steels, it can cause loss of ductility or load-carrying ability, cracking (usually as submicroscopic cracks) or catastrophic brittle failures at applied stresses well below the yield strength
26、 or even the normal design strength for the alloys. This phenomenon often occurs in alloys that show no significant loss in ductility when measured by conventional tensile tests, and is frequently referred to as hydrogen-induced delayed brittle failure, hydrogen stress cracking or hydrogen embrittle
27、ment. The hydrogen can be introduced during heat treatment, gas carburizing, cleaning, pickling, phosphating, electroplating and in the service environment as a result of cathodic protection or corrosion reactions. Hydrogen can also be introduced during fabrication, for example during roll forming,
28、machining, and drilling due to coolant or lubricant break-down as well as during welding or brazing operations. 1 Scope This International Standard specifies a preloading test which is able to detect the occurence of hydrogen embrittlement of fasteners at room temperature. This test is applicable to
29、 metric bolts, screws and studs; thread rolling screws; self-tapping screws; self-drilling screws; nuts; washers which are made of steel and are under tensile stress. The test shall be carried out within a temperature range of 10 C to 35 C. The test is suitable only for in-process control and may be
30、 carried out after any step of the manufacturing process. It is not intended as an acceptance test. It is capable of assessing differences or changes in processing conditions or techniques and to determine the effectiveness of the various processing steps including pre- and post-coating treatments (
31、baking) to reduce the mobile hydrogen in the fasteners. This test does not relieve the manufacturer or processor from the responsibility of imposing and monitoring suitable process control. NOTEThe chance of detecting hydrogen embrittlement decreases significantly if the test is started more than 24
32、 h after the last step of manufacturing process. Therefore, in normal cases this test is not suitable for acceptance testing. Special attention shall be given to the reference test in clause 7.3. 2 Normative references The following normative documents contain provisions which, through reference in
33、this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the
34、most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 273:1979, Fasteners Clearance holes for bolts and screw
35、s. ISO 2702:1992, Heat-treated steel tapping screws Mechanical properties. ISO 7085:1999, Mechanical and performance requirements of case hardened and tempered metric thread rolling screws. ISO 10666:1999, Drilling screws with tapping screw thread Mechanical and functional properties. 3 Terms and de
36、finitions For the purposes of this International Standard the following terms and definitions apply. 3.1 susceptibility to hydrogen embrittlement characteristic of a steel fastener to display brittle failure due to the presence of mobile hydrogen and when subjected to a significant degree of tensile
37、 stress and/or adverse service conditions NOTE 1With increasing susceptibility to hydrogen embrittlement, the critical amount of mobile hydrogen which may cause brittle failure decreases markedly. NOTE 2After the manufacturing process, susceptibility to hydrogen embrittlement cannot be reduced or ch
38、anged into an unsusceptible condition, even by any post-coating heat treatment (baking). 3.2 risk of hydrogen embrittlement risk of failure which arises if fasteners made from steel which are susceptible to hydrogen embrittlement absorb hydrogen and are subjected to tensile stress and/or residual te
39、nsile stress NOTEThe risk of hydrogen embrittlement can be reduced when in the relevant process steps hydrogen supply is minimized and/or when suitable post-coating heat treatment is carried out to enable hydrogen to effuse and/or to trap hydrogen irreversibly in the steel.EN ISO 15330:1999 2 BSI 04
40、-2000 3.3 manufacturing lot quantity of fasteners of a single designation including product grade, property class and size, manufactured from bar, wire, rod or flat product from a single cast, processed through the same or similar steps at the same time or over a continuous time period through the s
41、ame heat treatment and/or coating process, if any same heat treatment or coating process means: for a continuous process, the same treatment cycle without any setting modification; for a discontinuous process, the same treatment cycle for identical consecutive loads (batches). NOTEThe manufacturing
42、lot may be split into a number of manufacturing batches for processing purposes and then reassembled into the same manufacturing lot. 3.4 manufacturing batch quantity of identical fasteners from the same manufacturing lot processed together at one time 4 Principle The preloading test is carried out
43、in suitable test devices. The fasteners are subjected to stress in the range of the yield point or the breaking torque either by torquing with a mating nut (or bolt) or by driving in a pretapped plate, see Figure 1 to Figure 3. Other loading systems and fixtures are permissible, provided that the re
44、quired stress in the range of the yield point or breaking torque of the relevant fastener can be achieved. The stress or torque is held at least for 48 h. After every 24 h the fasteners are retightened to the initial stress or torque and at the same time checked if failure due to hydrogen embrittlem
45、ent has occurred. 5 Test apparatus According to the different types of fasteners different test devices shall be used. aclearance hole according to ISO 273, fine series Figure 1 Test devices for metric bolts, screws and studsEN ISO 15330:1999 BSI 04-2000 3 5.1 Metric bolts, screws and studs For metr
46、ic bolts, screws and studs fixtures of hardened plates of steel with parallel faces and with one hole or with multiple holes perpendicular to the surfaces of the plates shall be used, see Figure 1. The apparatus for metric bolts, screws and studs comprises a top and a bottom steel plate, see Figure
47、1. The hardness of top plate and bottom plate shall be 45 HRC minimum. The bearing surfaces shall be ground, and the roughness shall not exceedR a= 8 4m. The thickness of each plate shall be 1d minimum (d is the nominal thread diameter). The clearance holes shall have diameters d hin accordance with
48、 ISO 273, fine series, and shall not be chamfered. The distance of the clearance holes, L, from each other shall be three diameters (3d) minimum. When carrying out the test, a free threaded length of at least 1d shall be subjected to stress, and no more than 5 full threads shall extend beyond the nu
49、t. To meet these requirements, one or more plates of steel with parallel and ground faces may be used as filler plate(s). The filler plate(s) may be manufactured from other steel grades and with a different hardness compared to upper and bottom plate. The bolts, screws and studs to be tested are preloaded by tensioning with a mating nut. In the case of studs or threaded rod, nuts shall be used at both sides of the test plate(s). When they are threaded with different pitch threads, the nut on the fine thre
