1、DEUTSCHE NORM Januarv 2000 Fasteners (IS0 15330 : 1999) Preloading test for the detection of hydrogen embrittlement - Parallel bearing surface method English version of DIN EN IS0 15330 DIN EN IS0 15330 - ICs 21.060.01 Verbindungselemente - Verspannungsversuch zur Entdeckung von Wasserstoffversprdun
2、g - Verfahren mit parallelen Auflageflchen (IS0 15330 : 1999) European Standard EN IS0 15330 : 1999 has the status of a DIN Standard. A comma is used as the decimal marker. National foreword This standard has been published in accordance with a decision taken by CEN/TC 185 to adopt, without alterati
3、on, International Standard IS0 15330 as a European Standard. The responsible German body involved in its preparation was the Normenausschuss Mechanische Ver- bindungse/emenfe (Fasteners Standards Committee). DIN EN 20273 and DIN EN IS0 2702 are the standards corresponding to International Standards
4、IS0 273 and IS0 2702, respectively, referred to in clause 2 of the EN. National Annex NA Standards referred to (and not included in Normative references and Annex ZA) DIN EN 20273 Fasteners - Clearance holes for bolts and screws (IS0 273 : 1979) DIN EN IS0 2702 Heat-treated steel tapping screws - Me
5、chanical properties (IS0 2702 : 1992) EN comprises 11 pages. No pari of this standard may be reproduced without the prior permission of Ref. No. DIN EN IS0 15330 : 2000-0 V Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany, s the exclusive right of sale for German
6、 Standards (DIN-Normen). English price group 08 Sales No. 1108 06.00 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN IS0 15330 September 1999 ICs 21.060.01 English version Fasteners Preloading test for the detection of hydrogen embrittlement - Paral le1 bearing surface met hod (IS0 15330 : 1999
7、) Elments de fixation - Essai de prcharge pour la dtection de la fragilisation par l?hydrogne - Mthode des plaques parallles (IS0 15330 : 1999) Verbindungselemente - Verspan- nungsversuch zur Entdeckung von Wasserstoffversprdung - Verfahren mit parallelen Auflageflchen (IS0 15330 : 1999 This Europea
8、n Standard was approved by CEN on 1999-07-21. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning
9、 such national stand- ards may be obtained on application to the Central Secretariat or to any CEN member. The European Standards exist in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own lang
10、uage and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain,
11、Sweden, Switzerland, and the United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels O 1999. CEN - All rights of exploitation in any form and by any means reserved worldwide for
12、CEN national members. Ref. No. EN IS0 15330 : 1999 E Page 2 EN IS0 15330 : 1999 Foreword International Standard IS0 15330 : 1999 Fasteners - Preloading test for the detection of hydrogen embrittlement - Parallel bearing surface method, which was prepared by ISO/TC 2 Fasteners of the International Or
13、ganization for Standardization, has been adopted by Technical Committee CEN/TC 185 Threaded and non-threaded mechanical fasteners and acces- sories, the Secretariat of which is held by DIN, as a European Standard. This European Standard shall be given the status of a national standard, either by pub
14、lication of an identical text or by endorsement, and conflicting national standards withdrawn, by March 2000 at the latest. In accordance with the CENKENELEC Internal Regulations, the national standards organizations of the follow- ing countries are bound to implement this European Standard: Austria
15、, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, the Netherlands, Norway, Portugal, Spain, Sweden, Switzerland, and the United Kingdom. Endorsement notice The text of the International Standard IS0 15330 : 1999 was approved by CEN as a Eu
16、ropean Standard without any modification. NOTE: Normative references to international publications are listed in Annex ZA (normative). Contents Page 1 Scope 3 2 Normative references 3 3 Terms and definitions . 4 4 Principle 4 5 Test apparatus 5 6 Sampling . 8 7 Test procedure 8 8 Test evaluation . 1
17、0 9 Test report 1 O Bibliography 10 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 or even the normal design stren
18、gth 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 embrittlement. The hydrogen can be introd
19、uced 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, machining, and drilling due to c
20、oolant or lubricant break-down as well as during welding or brazing operations. Page 3 EN IS0 15330 : 1999 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 - me
21、tric 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 OC to 35 OC. The test is suitable only for in-process control a
22、nd may be 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 tre
23、atments (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. NOTE the last step of manufacturing process. Therefore, in normal cases this test is not suitable for
24、 acceptance testing. Special attention shall be given to the reference test in clause 7.3. The chance of detecting hydrogen embrittlement decreases significantly if the test is started more than 24 h after 2 Normative references The following normative documents contain provisions which, through ref
25、erence in 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 app
26、lying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IS0 and IEC maintain registers of currently valid International Standards. IS0 273:1979, Fasteners - Clearance holes for bol
27、ts and screws. IS0 2702: 1992, Heat-treated steel tapping screws - Mechanical properties. Page 4 EN IS0 15330 : 1999 IS0 7085:i 999, Mechanical and performance requirements of case hardened and tempered metric thread rolling screws. IS0 10666:1999, Drilling screws with tapping screw thread - Mechani
28、cal and functional properties. 3 Terms and definitions 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
29、 subjected to a significant degree of tensile stress and/or adverse service conditions NOTE 1 brittle failure decreases markedly. NOTE 2 unsusceptible condition, even by any post-coating heat treatment (baking). With increasing susceptibility to hydrogen embrittlement, the critical amount of mobile
30、hydrogen which may cause After the manufacturing process, susceptibility to hydrogen ernbrittlement cannot be reduced or changed into an 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 ar
31、e subjected to tensile stress and/or residual tensile stress NOTE The 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 irr
32、eversibly in the steel. 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 pe
33、riod through the same 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).
34、NOTE reassembled into the same manufacturing lot. The manufacturing lot may be split into a number of manufacturing batches for processing purposes and then 3.4 manufacturing batch quantity of identical fasteners from the same manufacturing lot processed together at one time 4 Principle The preloadi
35、ng test is carried out 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 Figures 1 to 3. Other loading systems and fixtures are permissible, pro
36、vided that the required 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 initiai stress or torque and at the same time checked if failure due to hy
37、drogen embrittlement has occurred. Page 5 EN IS0 15330 : 1999 5 Test apparatus According to the different types of fasteners different test devices shall be used. 5.1 Metric bolts, screws and studs For metric bolts, screws and studs fixtures of hardened plates of steel with parallel faces and with o
38、ne hole or with multiple holes perpendicular to the surfaces of the plates shall be used, see Figure 1, Key 1 Upper plate 2 3 Lower plate 4 Nut serving as head Filler plate (for long bolts, screws or studs) a Clearance hole according to IS0 273, fine series Figure 1 -Test devices for metric bolts, s
39、crews and studs The apparatus for metric bolts, screws and studs comprises a top and a bottom steel plate, see Figure 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 exceed Ru = 8 pm. The thickness of each plate
40、 shall be Id minimum (d is the nominal thread diameter). The clearance holes shall have diameters d, in accordance with IS0 273, fine series, and shall not be chamfered. The distance of the clearance holes, L, from each other shall be three diameters (34 minimum. When carrying out the test, a free t
41、hreaded length of at least Id shall be subjected to stress, and no more than 5 full threads shall extend beyond the nut. 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 gra
42、des and with a different hardness compared to upper and bottom plate. Page 6 EN IS0 15330 : 1999 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
43、 with different pitch threads, the nut on the fine thread shall be considered as the head. The nut representing the head shall be screwed to finger tightness up to the relevant thread end. In the case of a short screw (i 2,5 d) only one plate with pretapped holes shall be used in which the screw sha
44、ll be screwed directly without using a nut and tightened against the screw head. The plate shall have the properties as specified above for the top plate. For testing bolts and screws with no flat bearing surface (e.g. countersunk screws, eye bolts etc.) an appropriate upper plate or washer shall be
45、 used under the head, see Figure 2. Key 1 Upper plate with countersinks 2 Lower plate Figure 2 - Example for a test device for bolts and screws with no fiat bearing surface 5.2 Thread rolling screws, self-tapping screws and self-drilling screws The apparatus for thread rolling screws, self-tapping s
46、crews and self-drilling screws comprises a plate made from steel with mechanical properties as specified for the corresponding drive test in IS0 7085, IC0 2702 or IS0 10666 respectively, but which is pretapped, see Figure 3. A suitable washer of hardness class 300 HV may be applied under the head of
47、 the screw to protect the plate. The minimum thickness of the plate shall be l (d = nominal thread diameter). All other requirements are the same as for metric bolts, screws and studs, see 5.1. NOTE Instead of using taps, pretapping can be achieved by driving the screws to be tested through holes wi
48、th diameters according to the relevant International Standards (see above), provided that the thread of the screw is long enough to complete the tapping of the mating thread. When the thread is completed, the required torque to continue the driving process is markedly reduced and is not increased as
49、 long as the clamping process is not started. For the testing of long screws, one or more plates of steel with parallel and surface ground faces may be used as filler plates. The diameter of the clearance hole in the plates shall not exceed the nominal thread diameter by more than 10 7. Page 7 EN IS0 15330 : 1999 I L13d I Key 1 2 Pretapped plate Filler plate (for long screws) a ddhSl,ld Figure 3 - Test apparatus for thread roiling screws, self-tapping screws or self-drilling screws 5.3 Screw and washer assemblies The testing of screw and washer assemblies shall be carrie
