1、BRITISH STANDARDBS EN 14831:2005Fasteners Tightening performance Torque/Angle simplified test method The European Standard EN 14831:2005 has the status of a British StandardICS 21.060.10; 21.060.20g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59
2、g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 14831:2005This British Standard was published under the authority of the Standards Policy and Strategy Committee on 12 December 2005 BSI 12 December 2005ISBN 0 580 47346 5National forewordThis Brit
3、ish Standard is the official English language version of EN 14831:2005. The UK participation in its preparation was entrusted by Technical Committee FME/9, Bolts, nuts and accessories, to Subcommittee FME/9/1, Materials, which has the responsibility to: request to its secretary.Cross-referencesThe B
4、ritish Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards
5、Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the respon
6、sible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK.Summary of pagesThis document comprises a front cover, an inside front cover, the
7、 EN title page, pages 2 to 23 and a back cover.The BSI copyright notice displayed in this document indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsA list of organizations represented on this subcommittee can be obtained on EUROPEAN STANDARDNORME E
8、UROPENNEEUROPISCHE NORMEN 14831April 2005ICS 21.060.10; 21.060.20English versionFasteners - Tightening performance - Torque/Angle simplifiedtest methodElments de fixation - Aptitude au serrage - Mthodedessai simplifie Couple/AngleVerbindungselemente - Anziehverhalten - VereinfachtesDrehmoment/Drehwi
9、nkel-VerfahrenThis European Standard was approved by CEN on 3 March 2005.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliograp
10、hical references concerning such nationalstandards 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 translationunder the responsibility of a CEN m
11、ember into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lith
12、uania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2005 CEN All righ
13、ts of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 14831:2005: EEN 14831:2005 (E) 2 Contents page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Symbols and units.5 5 Test principle6 6 Apparatus .6 6.1 Test device .6 6.2
14、Test fixture7 6.3 Reference fasteners 10 6.4 Fasteners to be tested.11 7 Test procedure.11 7.1 General11 7.2 Test procedure for nut testing11 7.3 Test procedure for bolt/screw testing .12 8 Evaluation of the results .13 9 Test report 13 Annex A (normative) Calibration method for determination of the
15、 angle test14 Annex B (normative) Determination of the control limit values for the torque (Tminand Tmax)17 Annex C (informative) Example of determination of the control limit values for the torque (Tminand Tmax)21 Bibliography 23 EN 14831:2005 (E) 3 Foreword This document (EN 14831:2005) has been p
16、repared by Technical Committee CEN/TC 185, “Threaded and non-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 b
17、y October 2005, and conflicting national standards shall be withdrawn at the latest by October 2005. This document includes a Bibliography. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard
18、: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 14831:2005 (E) 4 1 Scop
19、e This document specifies a test method for fasteners with ISO metric thread from M6 to M16 and with property classes 8.8 to 12.9 for bolts and screws and with property classes 8 to 12 for nuts, to check their tightening performance in the elastic range. It applies to steel fasteners with an ISO met
20、ric thread according to ISO 68-1. It applies to fasteners having a friction coefficient from 0,06 up to and including 0,18. For higher values of friction coefficients, the dispersion of test results increases and the test method should not be applied. For lower values friction of coefficients, which
21、 are for very specific applications and require special lubrication, this document does not apply. This comparative test method can be used to monitor stability of a production process (such as coating, lubrication, shot-blasting) or to compare various production manufacturing lots. It can also be u
22、sed to detect fasteners, which are out of specification. NOTE This simplified test method has been developed to avoid systematic use of more complex procedures. In case of dispute the torque/tension test method according to EN ISO 16047 is the referee test. This document does not apply for assessmen
23、t of fasteners in actual assembly conditions; it does not allow the measurement of operating friction coefficients. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated refe
24、rences, the latest edition of the referenced document (including any amendments) applies. EN 20898-2, Mechanical properties of fasteners Part 2: Nuts with specified proof load values Coarse thread (ISO 898-2:1992). EN ISO 898-1, Mechanical properties of fasteners made of carbon steel and alloy steel
25、 Part 1: Bolts, screws and studs (ISO 898-1:1999). EN ISO 4759-3, Tolerances for fasteners Part 3: Plain washers for bolts, screws and nuts Product grades A and C (ISO 4759-3:2000). EN ISO 7093-1, Plain washers Large series Part 1: Product grade A (ISO 7093-1:2000). EN ISO 16047, Fasteners Torque/cl
26、amp force testing (ISO 16047:2005). ISO 965-2, ISO general purpose metric screw threads Tolerances Part 2: Limits of sizes for general purpose external and internal screw threads Medium quality. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1
27、 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 same heat
28、treatment and/or coating process, if any NOTE 1 Same heat treatment or coating process means: EN 14831:2005 (E) 5 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). NOTE
29、 2 The manufacturing lot may be split into a number of manufacturing batches for processing purposes and then reassembled into the same manufacturing lot. Adapted from EN ISO 15330:1999 3.2 coating process cycle a sequence of surface preparation and/or coating application during a period of time whe
30、re operating parameters including temperature, concentration, surface area, current density, or any other parameter which may affect the mechanical and/or performance properties of the fasteners are set and maintained 3.3 heat treatment cycle a sequence of heat treatment over a defined period of tim
31、e where operating parameters such as temperature, atmosphere, pressure, retention time, or any other parameter which may affect the mechanical or performance properties of the fasteners are set and maintained 4 Symbols and units d Nominal diameter of the bolt, screw or nut, mm deExternal diameter of
32、 the bearing part, mm dhDiameter of the clearance hole (block or bearing part/washer, mm) dwOutside diameter of the bearing face of the bolt, screw or nut, mm DbDiameter of bearing surface under nut or bolt head for friction (see EN ISO 16047) d2Basic pitch diameter, mm F Force Fp, maxClamping force
33、 corresponding to Tpin correlation with min, N Fp, minClamping force corresponding to Tpin correlation with max, N FpClamping force corresponding to Tp, N Ftest, maxMaximum clamping force, N Ftest, minMinimum clamping force, N FtestNominal clamping force, N H Height of the tightening block, mm h Thi
34、ckness of the bearing part, mm L Side dimension of the tightening block, mm LcClamping length, mm n Number of tested bolts, screws or nuts. P Pitch of the thread, mm rmMean effective radius of the bearing face, mm T Torque T Mean torque for calibration, Nm TmaxMaximum torque value, Nm EN 14831:2005
35、(E) 6 TminMinimum torque value, Nm TpPretorque, Nm TtestTorque corresponding to Ftest, Nm Angle of rotation testAngle value measured between Tpand Ttestin degrees maxUpper limit of the specified range of friction coefficient minLower limit of the specified range of friction coefficient 5 Test princi
36、ple The principle of this test is to apply a specified clamping force to the bolt/screw by rotating the fastener (bolt/screw or nut) to be tested under reference conditions. After applying a pretorque the fastener to be tested is tightened to a specified test angle. The final torque is monitored and
37、 compared to a specified torque range. 6 Apparatus 6.1 Test device The torque wrench shall be able to apply a tightening torque within the uncertainty of 2 % of the value to be measured. The uncertainty of angle measurement shall be 2 or 2 % of the measured value, whichever is greater. EN 14831:2005
38、 (E) 7 6.2 Test fixture 6.2.1 General The test fixture includes a tightening block and a bearing part, see Figure 1. a) Nut testing b) Bolt/screw testing Key 1 Tightening block 2 Bearing part 3 Nut to be tested 4 Reference bolt/screw 5 Bolt/screw to be tested 6 Reference nut Figure 1 Test fixture Th
39、e reference fastener and the bearing part/washer shall not rotate during the test. Any device used to prevent rotation shall not intrude into the bearing face of the fastener to be tested. 6.2.2 Tightening block The tightening block shall be made of steel quenched and tempered to a hardness equal to
40、 or above 50 HRC. It shall be dry and clean. The bearing surface shall be uncoated. EN 14831:2005 (E) 8 Dimensions of the tightening block see Figure 2 and Table 1. Dimensions in millimetres Figure 2 Tightening block EN 14831:2005 (E) 9 Table 1 Dimensions of tightening block Dimensions in milimetres
41、 Thread of the fastener to be tested d M6 M8 M10 M12 M14 M16 L 50 0,5 min. 6,40 8,40 10,50 13,00 15,00 17,00 dhmax. 6,55 8,55 10,65 13,18 15,18 17,18 Hnomfor testing nuts 25 25 35 35 50 50 Hnomfor screws (fully threaded) 9,00 12,00 15,00 18,00 21,00 24,00 l Hnomfor bolts (partially threaded) 30 35 2
42、0 40 45 30 25 50 25 25 55 35 35 60 45 35 35 65 45 70 50 45 45 38 38 80 60 60 50 50 90 65 65 60 100 78 78 65 110 85 78 120 95 85 130 95 140 110 100 150 160 120 EN 14831:2005 (E) 10 6.2.3 Bearing part/washer The bearing part/washer shall be taken from a single manufacturing lot. They shall be free of
43、burrs, uncoated, dry and clean. The hardness of the bearing part shall be 200 HV minimum and the hardness class of the washer shall be 200 HV according to EN ISO 7093-1. The roughness Rashall be 1,6 maximum. Dimensions see Figure 3 and Table 2. Dimensions in millimetres aFor M6 to M10: t = 0,2 mm Fo
44、r M12 to M16: t = 0,3 mm Figure 3 Bearing part/washer Table 2 Bearing part/washer dimensions Dimensions in millimetres Thread of the fastener to be tested d M6 M8 M10 M12 M14 M16 demin.a17,57 23,48 29,48 36,38 43,38 49,38 min. 6,60 9,00 11,00 13,50 15,50 17,50 dhmax. 6,82 9,22 11,27 13,77 15,77 17,7
45、7 min. 1,40 1,80 2,30 2,70 2,70 2,70 h max. 1,8 2,2 2,7 3,3 3,3 3,3 NOTE de, minand h according to EN ISO 7093-1; dhaccording to EN 20273 medium series, tolerance H13. Thickness variation h according to EN ISO 4759-3. ade, minshall be greater than the outside diameter of the bearing face of the fast
46、ener to be tested. 6.3 Reference fasteners 6.3.1 General Reference fasteners shall be uncoated, dry and clean. No lubricant shall be added before testing. Reference fasteners shall be from a single manufacturing lot. They may be protected against corrosion by applying an agent which shall be fully r
47、emoved by solvent bath cleaning before each test series. EN 14831:2005 (E) 11 6.3.2 Reference bolts/screws (for nut testing) The property class of the references bolt/screw according to EN ISO 898-1 shall correspond to the property class of the nut to be tested according to EN 20898-2, however, shal
48、l not be less than property class 8.8. The thread tolerance class of the bolt shall be 6g according to ISO 965-2. All screw threads shall be rolled. The length of the reference bolt/screw shall be in accordance with Figure 1a). 6.3.3 Reference nuts (for bolt/screw testing) For the testing of bolt/sc
49、rew of property class 10.9 and lower, the nut shall be style 1 and shall have property class 10 according to EN 20898-2. For the testing of bolts/screws of property class 12.9, the nut shall have property class 12. The thread tolerance class of the reference nuts shall be 6H. 6.4 Fasteners to be tested The fasteners to be tested shall be from the same manufacturing lot. They shall be in the delivery condition; no additional lubricant shall be added before testing. Unless otherw
