1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 376:2011Metallic materials Calibration of force-provinginstruments used for theverification of uniaxial testingmachines (ISO 376:2011)BS EN ISO 376:2011 BRITISH STANDAR
2、DNational forewordThis British Standard is the UK implementation of EN ISO 376:2011. Itsupersedes BS EN ISO 376:2004 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee ISE/101/1, Uniaxial testing.A list of organizations represented on this committee can be
3、obtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 59606 3ICS 17.100; 77.040.10Compliance with a British Standard cannot confer immunity fromlegal obliga
4、tions.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 30 June 2011.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 376 June 2011 ICS 77.040.10 Supersedes EN ISO 376:2004English Vers
5、ion Metallic materials - Calibration of force-proving instruments used for the verification of uniaxial testing machines (ISO 376:2011)Matriaux mtalliques - talonnage des instruments de mesure de force utiliss pour la vrification des machines dessais uniaxiaux (ISO 376:2011) Metallische Werkstoffe -
6、 Kalibrierung der Kraftmessgerte fr die Prfung von Prfmaschinen mit einachsiger Beanspruchung (ISO 376:2011) This European Standard was approved by CEN on 4 June 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European St
7、andard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member. This European Standard exists in three official versions (Engl
8、ish, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium,
9、Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE
10、 FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 376:2011: EBS EN ISO 376:2011EN ISO 37
11、6:2011 (E) 3 Foreword This document (EN ISO 376:2011) has been prepared by Technical Committee ISO/TC 164 “Mechanical testing of metals“ in collaboration with Technical Committee ECISS/TC 101 “Test methods for steel (other than chemical analysis)” the secretariat of which is held by AFNOR. This Euro
12、pean Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by December 2011, and conflicting national standards shall be withdrawn at the latest by December 2011. Attention is drawn to the possibility that some of the e
13、lements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 376:2004. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the follo
14、wing countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slova
15、kia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 376:2011 has been approved by CEN as a EN ISO 376:2011 without any modification. BS EN ISO 376:2011ISO 376:2011(E) ISO 2011 All rights reserved iiiContents Page Foreword iv Introduction.v 1 Scope1 2
16、Normative references1 3 Terms and definitions .1 4 Symbols and their designations 1 5 Principle2 6 Characteristics of force-proving instruments 3 7 Calibration of the force-proving instrument.3 8 Classification of the force-proving instrument 8 9 Use of calibrated force-proving instruments10 Annex A
17、 (informative) Example of dimensions of force transducers and corresponding loading fittings.11 Annex B (informative) Additional information .18 Annex C (informative) Measurement uncertainty of the calibration and subsequent use of the force-proving instrument21 Bibliography30 BS EN ISO 376:2011ISO
18、376:2011(E) iv ISO 2011 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member
19、 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 part in the work. ISO collaborates closely with the International Elect
20、rotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopte
21、d by the 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. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
22、 rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 376 was prepared by Technical Committee ISO/TC 164, Mechanical testing of metals, Subcommittee SC 1, Uniaxial testing. This fourth edition cancels and replaces the third edition (ISO 376:2004), which has be
23、en technically revised (for details, see the introduction). BS EN ISO 376:2011ISO 376:2011(E) ISO 2011 All rights reserved vIntroduction An ISO/TC 164/SC 1 working group has developed procedures for determining the measurement uncertainty of force-proving instruments, and these procedures have been
24、added to this fourth edition as a new annex (Annex C). In addition, this fourth edition allows the calibration to be performed in two ways: with reversible measurement for force-proving instruments which are going to be used with increasing and decreasing forces; without reversible measurement for f
25、orce-proving instruments which are going to be used only with increasing forces. In the first case, i.e. when the force-proving instrument is going to be used for reversible measurements, the calibration has to be performed with increasing and decreasing forces to determine the hysteresis of the for
26、ce-proving instrument. In this case, there is no need to perform a creep test. In the second case, i.e. when the force-proving instrument is not going to be used for reversible measurements, the calibration is performed with increasing forces only but, in addition, a creep test has to be performed.
27、In this case, there is no need to determine the hysteresis. BS EN ISO 376:2011BS EN ISO 376:2011INTERNATIONAL STANDARD ISO 376:2011(E) ISO 2011 All rights reserved 1Metallic materials Calibration of force-proving instruments used for the verification of uniaxial testing machines 1 Scope This Interna
28、tional Standard specifies a method for the calibration of force-proving instruments used for the static verification of uniaxial testing machines (e.g. tension/compression testing machines) and describes a procedure for the classification of these instruments. This International Standard is applicab
29、le to force-proving instruments in which the force is determined by measuring the elastic deformation of a loaded member or a quantity which is proportional to it. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references,
30、only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories 3 Terms and definitions For the purposes of this document, the foll
31、owing terms and definitions apply. 3.1 force-proving instrument whole assembly from the force transducer through to, and including, the indicator 4 Symbols and their designations Symbols and their designations are given in Table 1. BS EN ISO 376:2011ISO 376:2011(E) 2 ISO 2011 All rights reservedTabl
32、e 1 Symbols and their designations Symbol Unit Designation b % Relative reproducibility error with rotation b % Relative repeatability error without rotation c % Relative creep error FfN Maximum capacity of the transducer FNN Maximum calibration force fc% Relative interpolation error f0% Relative ze
33、ro error if Readingaon the indicator after removal of force io Readingaon the indicator before application of force i30 Readingaon the indicator 30 s after application or removal of the maximum calibration force i300 Readingaon the indicator 300 s after application or removal of the maximum calibrat
34、ion force r N Resolution of the indicator v % Relative reversibility error of the force-proving instrument X Deflection with increasing test force Xa Computed value of deflection X Deflection with decreasing test force Xmax Maximum deflection from runs 1, 3 and 5 Xmin Minimum deflection from runs 1,
35、 3 and 5 XN Deflection corresponding to the maximum calibration force rX Average value of the deflections with rotation wrX Average value of the deflections without rotation aReading value corresponding to the deflection. 5 Principle Calibration consists of applying precisely known forces to the for
36、ce transducer and recording the data from the indicator, which is considered an integral part of the force-proving instrument. When an electrical measurement is made, the indicator may be replaced by another indicator and the force-proving instrument need not be recalibrated provided the following c
37、onditions are fulfilled. a) The original and replacement indicators have calibration certificates, traceable to national standards, which give the results of calibration in terms of electrical base units (volt, ampere). The replacement indicator shall be calibrated over a range equal to or greater t
38、han the range for which it is used with the force-proving instrument, and the resolution of the replacement indicator shall be at least equal to the resolution of the original indicator when it is used with the force-proving instrument. b) The units and excitation source of the replacement indicator
39、 should be respectively of the same quantity (e.g. 5 V, 10 V) and type (e.g. AC or DC carrier frequency). c) The uncertainty of each indicator (both the original and the replacement indicators) shall not significantly influence the uncertainty of the whole force-proving instrument assembly. It is re
40、commended that the uncertainty of the replacement indicator be no greater than 1/3 of the uncertainty of the entire system (see C.2.11). BS EN ISO 376:2011ISO 376:2011(E) ISO 2011 All rights reserved 36 Characteristics of force-proving instruments 6.1 Identification of the force-proving instrument A
41、ll the elements of the force-proving instrument (including the cables for electrical connection) shall be individually and uniquely identified, e.g. by the name of the manufacturer, the model and the serial number. For the force transducer, the maximum working force shall be indicated. 6.2 Applicati
42、on of force The force transducer and its loading fittings shall be designed so as to ensure axial application of force, whether in tension or compression. Examples of loading fittings are given in Annex A. 6.3 Measurement of deflection Measurement of the deflection of the loaded member of the force
43、transducer may be carried out by mechanical, electrical, optical or other means with adequate accuracy and stability. The type and the quality of the deflection measuring system determine whether the force-proving instrument is classified only for specific calibration forces or for interpolation (se
44、e Clause 7). Generally, the use of force-proving instruments with dial gauges as a means of measuring the deflection is limited to the forces for which the instruments have been calibrated. The dial gauge, if used over a long travel, may contain large localized periodic errors which produce an uncer
45、tainty too great to permit interpolation between calibration forces. The dial gauge may be used for interpolation if its periodic error has a negligible influence on the interpolation error of the force-proving instrument. 7 Calibration of the force-proving instrument 7.1 General 7.1.1 Preliminary m
46、easures Before undertaking the calibration of the force-proving instrument, ensure that this instrument is able to be calibrated. This can be done by means of preliminary tests such as those defined below and given as examples. 7.1.2 Overloading test This optional test is described in Clause B.1. 7.
47、1.3 Verification relating to application of forces Ensure that the attachment system of the force-proving instrument allows axial application of the force when the instrument is used for tensile testing; that there is no interaction between the force transducer and its support on the calibration mac
48、hine when the instrument is used for compression testing. Clause B.2 gives an example of a method that can be used. NOTE Other tests can be used, e.g. a test using a flat-based transducer with a spherical button or upper bearing surface. BS EN ISO 376:2011ISO 376:2011(E) 4 ISO 2011 All rights reserv
49、ed7.1.4 Variable voltage test This test is left to the discretion of the calibration service. For force-proving instruments requiring an electrical supply, verify that a variation of 10 % of the line voltage has no significant effect. This verification can be carried out by means of a force transducer simulator or by another appropriate method. 7.2 Resolution of the indicator 7.2.1 Analogue scale The thickness of the graduation marks on the scale shall be uniform and the width of the pointer shall be approximatel
