SIST EN ISO 7500-1:2016
(Main)Metallic materials - Verification of static uniaxial testing machines - Part 1: Tension/compression testing machines - Verification and calibration of the force-measuring system (ISO 7500-1:2015)
Metallic materials - Verification of static uniaxial testing machines - Part 1: Tension/compression testing machines - Verification and calibration of the force-measuring system (ISO 7500-1:2015)
This part of ISO 7500 specifies the calibration and verification of tension/compression testing machines.
The verification consists of:
— a general inspection of the testing machine, including its accessories for the force application;
— a calibration of the force-measuring system of the testing machine;
— a confirmation that the performance properties of the testing machine achieve the limits given for
a specified class.
NOTE This part of ISO 7500 addresses the static calibration and verification of the force-measuring
systems. The calibration values are not necessarily valid for high-speed or dynamic testing applications. Further
information regarding dynamic effects is given in the Bibliography.
CAUTION — Some of the tests specified in this part of ISO 7500 involve the use of processes
which could lead to a hazardous situation.
Metallische Werkstoffe - Prüfung von statischen einachsigen Prüfmaschinen - Teil 1: Zug und Druckprüfmaschinen - Prüfung und Kalibrierung der Kraftmesseinrichtung (ISO 7500-1:2015)
Dieser Teil von ISO 7500 legt die Überprüfung von Zug und Druckprüfmaschinen fest.
Diese Überprüfung besteht aus:
- einer allgemeinen Inspektion der Prüfmaschine einschließlich der Maschinenteile für die Kraft¬aufbringung;
- einer Kalibrierung der Kraftmesseinrichtung.
ANMERKUNG Dieser Teil von ISO 7500 betrifft nur die statische Prüfung und Kalibrierung von Kraftmess-einrichtungen. Die Kalibrierergebnisse können nur mit Einschränkungen für dynamische und Hochgeschwindig-keitsprüfmaschinen verwendet werden. Weitere Informationen bezüglich dynamischer Effekte sind in den Literatur-hinweisen angegeben.
Matériaux métalliques - Vérification des machines pour essais statiques uniaxiaux - Partie 1: Machines d'essai de traction/compression - Vérification et étalonnage du système de mesure de force (ISO 7500-1:2015)
ISO 7500-1:2015 spécifie l'étalonnage et la vérification des machines d'essai de traction/compression.
La vérification consiste en:
- une inspection générale de la machine d'essai, y compris ses accessoires pour l'application des forces;
- un étalonnage du système de mesure de force.
- une confirmation que les propriétés de la machine d'essai concernant ses performances atteignent les limites indiquées pour une classe spécifiée.
NOTE La présente partie de l'ISO 7500 traite de l'étalonnage et de la vérification statique des systèmes de mesure de force. Les valeurs d'étalonnage ne sont pas nécessairement valables pour les applications d'essais dynamiques ou à grande vitesse. La bibliographie donne des informations complémentaires sur les effets dynamiques.
ATTENTION ? Certains des essais spécifiés dans cette partie de l'ISO 7500 implique l'utilisation de processus qui pourrait conduire à une situation dangereuse.
Kovinski materiali - Preverjanje statičnih enoosnih preskuševalnih strojev - 1. del: Preskuševalni stroji za natezni/tlačni preskus - Preverjanje in umerjanje sistema za merjenje sile (ISO 7500-1:2015)
Ta del standarda ISO 7500 določa metodo za umerjanje in preverjanje preskuševalnih strojev za natezni/tlačni preskus.
Preverjanje je sestavljeno iz:
– splošnega pregleda preskuševalnega stroja, vključno z njegovimi priključki za uvajanje sile;
– umerjanja sistema za merjenje sile preskuševalnega stroja;
– potrditve, da zmogljivosti preskuševalnega stroja dosegajo mejne vrednosti, podane za
določen razred.
OPOMBA: Ta del standarda ISO 7500 obravnava statično umerjanje in preverjanje sistemov za natezni/tlačni
preskus. Ni nujno, da vrednosti umerjanja veljajo za uporabo pri visokih hitrostih ali dinamičnemu preskušanju. Dodatne informacije o dinamičnih učinkih so podane v bibliografiji.
POZOR – Nekateri preskusi, podani v tem delu standarda ISO 7500, vključujejo uporabo postopkov, ki lahko vodijo v nevarno stanje.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 7500-1:2016
01-marec-2016
1DGRPHãþD
SIST EN ISO 7500-1:2004
SIST EN ISO 7500-1:2004/AC:2009
.RYLQVNLPDWHULDOL3UHYHUMDQMHVWDWLþQLKHQRRVQLKSUHVNXãHYDOQLKVWURMHYGHO
3UHVNXãHYDOQLVWURML]DQDWH]QLWODþQLSUHVNXV3UHYHUMDQMHLQXPHUMDQMHVLVWHPD]D
PHUMHQMHVLOH ,62
Metallic materials - Verification of static uniaxial testing machines - Part 1:
Tension/compression testing machines - Verification and calibration of the force-
measuring system (ISO 7500-1:2015)
Metallische Werkstoffe - Prüfung von statischen einachsigen Prüfmaschinen - Teil 1: Zug
und Druckprüfmaschinen - Prüfung und Kalibrierung der Kraftmesseinrichtung (ISO 7500
-1:2015)
Matériaux métalliques - Vérification des machines pour essais statiques uniaxiaux -
Partie 1: Machines d'essai de traction/compression - Vérification et étalonnage du
système de mesure de force (ISO 7500-1:2015)
Ta slovenski standard je istoveten z: EN ISO 7500-1:2015
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
SIST EN ISO 7500-1:2016 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN ISO 7500-1:2016
---------------------- Page: 2 ----------------------
SIST EN ISO 7500-1:2016
EN ISO 7500-1
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2015
EUROPÄISCHE NORM
ICS 77.040.10 Supersedes EN ISO 7500-1:2004
English Version
Metallic materials - Calibration and verification of static
uniaxial testing machines - Part 1: Tension/compression
testing machines - Calibration and verification of the force-
measuring system (ISO 7500-1:2015)
Matériaux métalliques - Étalonnage et vérification des Metallische Werkstoffe - Kalibrierung und
machines pour essais statiques uniaxiaux - Partie 1: Überprüfung von statischen einachsigen
Machines d'essai de traction/compression - Étalonnage Prüfmaschinen - Teil 1: Zug- und Druckprüfmaschinen
et vérification du système de mesure de force (ISO - Kalibrierung und Überprüfung der
7500-1:2015) Kraftmesseinrichtung (ISO 7500-1:2015)
This European Standard was approved by CEN on 21 November 2015.
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 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 (English, 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, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 7500-1:2015 E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 7500-1:2016
EN ISO 7500-1:2015 (E)
Contents Page
European foreword . 3
2
---------------------- Page: 4 ----------------------
SIST EN ISO 7500-1:2016
EN ISO 7500-1:2015 (E)
European foreword
This document (EN ISO 7500-1:2015) 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 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 June 2016, and conflicting national standards shall be
withdrawn at the latest by June 2016.
Attention is drawn to the possibility that some of the elements 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 7500-1:2004.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 7500-1:2015 has been approved by CEN as EN ISO 7500-1:2015 without any
modification.
3
---------------------- Page: 5 ----------------------
SIST EN ISO 7500-1:2016
---------------------- Page: 6 ----------------------
SIST EN ISO 7500-1:2016
INTERNATIONAL ISO
STANDARD 7500-1
Fourth edition
2015-12-15
Metallic materials — Calibration and
verification of static uniaxial testing
machines —
Part 1:
Tension/compression testing machines
— Calibration and verification of the
force-measuring system
Matériaux métalliques — Étalonnage et vérification des machines
pour essais statiques uniaxiaux —
Partie 1: Machines d’essai de traction/compression — Étalonnage et
vérification du système de mesure de force
Reference number
ISO 7500-1:2015(E)
©
ISO 2015
---------------------- Page: 7 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2015, Published in Switzerland
All rights reserved. Unless otherwise 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 or ISO’s member body in the country of
the requester.
ISO copyright office
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2015 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and their meanings . 2
5 General inspection of the testing machine . 3
6 Calibration of the force-measuring system of the testing machine . 3
6.1 General . 3
6.2 Determination of the resolution . 4
6.2.1 Analogue scale . 4
6.2.2 Digital scale. 4
6.2.3 Variation of readings . 4
6.2.4 Unit . 5
6.3 Prior determination of the relative resolution of the force indicator . 5
6.4 Calibration procedure . 5
6.4.1 Alignment of the force-proving instrument . 5
6.4.2 Temperature compensation . 5
6.4.3 Conditioning of the testing machine and force-proving instrument . 5
6.4.4 Procedure . 5
6.4.5 Application of discrete forces . 6
6.4.6 Verification of accessories . 6
6.4.7 Verification of the effect of differences in piston positions . 7
6.4.8 Determination of relative reversibility error . 7
6.5 Assessment of the force indicator . 8
6.5.1 Relative indication error . 8
6.5.2 Relative repeatability error . 9
6.5.3 Agreement between two force-proving instruments . 9
7 Class of testing machine range . 9
8 Verification report .10
8.1 General .10
8.2 General information .10
8.3 Results of verification .10
9 Intervals between verifications .11
Annex A (normative) General inspection of the testing machine.12
Annex B (informative) Inspection of the loading platens of the compression testing machines .13
Annex C (informative) Uncertainty of the calibration results of the force-measuring system .14
Bibliography .18
© ISO 2015 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
Foreword
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 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 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 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 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 list 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 as information about ISO’s adherence to the WTO principles in the Technical
Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 164, Mechanical testing of metals, Subcommittee
SC 1, Uniaxial testing.
This fourth edition cancels and replaces the third edition (ISO 7500-1:2004) which has been
technically revised.
ISO 7500 consists of the following parts, under the general title Metallic materials — Calibration and
verification of static uniaxial testing machines:
— Part 1: Tension/compression testing machines — Calibration and verification of the force-measuring
system
— Part 2: Tension creep testing machines — Verification of the applied force
iv © ISO 2015 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 7500-1:2016
INTERNATIONAL STANDARD ISO 7500-1:2015(E)
Metallic materials — Calibration and verification of static
uniaxial testing machines —
Part 1:
Tension/compression testing machines — Calibration and
verification of the force-measuring system
1 Scope
This part of ISO 7500 specifies the calibration and verification of tension/compression testing machines.
The verification consists of:
— a general inspection of the testing machine, including its accessories for the force application;
— a calibration of the force-measuring system of the testing machine;
— a confirmation that the performance properties of the testing machine achieve the limits given for
a specified class.
NOTE This part of ISO 7500 addresses the static calibration and verification of the force-measuring
systems. The calibration values are not necessarily valid for high-speed or dynamic testing applications. Further
information regarding dynamic effects is given in the Bibliography.
CAUTION — Some of the tests specified in this part of ISO 7500 involve the use of processes
which could lead to a hazardous situation.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 376, Metallic materials — Calibration of force-proving instruments used for the verification of uniaxial
testing machines
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
calibration
operation that establishes the relationship between the force values (with associated uncertainties)
indicated by the testing machine and those measured by one or more force-proving instruments
3.2
verification
confirmation, based on analysis of measurements in accordance with this standard, that the
performance properties of the testing machine achieve the limits given for a specified class
© ISO 2015 – All rights reserved 1
---------------------- Page: 11 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
4 Symbols and their meanings
Symbols and their meanings are given in Table 1.
Table 1 — Symbols and their meanings
Symbol Unit Meaning
a % Relative resolution of the force indicator of the testing machine
a % Relative resolution of the force indicator of the testing machine at the applied force
F
a % Relative resolution of the force indicator of the testing machine at zero force
Z
b % Relative repeatability error of the force-measuring system of the testing machine
b % Allowable value of b for a given class
al
ΔF N Relative error of the force
Δm kg Relative error of the mass
2
Δg m/s Relative error of the acceleration due to gravity
E % Estimated mean relative error
E’ % Estimated mean relative reversibility error
f % Relative zero error of the force-measuring system of the testing machine
0
F N Reference force indicated by the force-proving instrument with increasing test
force
F’ N Reference force indicated by the force-proving instrument with decreasing test
force
F N Reference force indicated by the force-proving instrument with increasing test
c
force, for the complementary series of measurements for the smallest range used
F N Force indicated by the force indicator of the testing machine to be verified, with
i
increasing test force
N Force indicated by the force indicator of the testing machine to be verified, with
′
F
i decreasing test force
N Arithmetic mean of several measurements of F and F for the same discrete force
i
FF,
i
F N Force reading on the force indicator of the testing machine to be verified, with
ic
increasing test force, for the complementary series of measurements for the
smallest range used
F N Residual indication of the force indicator of the testing machine to be verified
i0
after removal of force
F N Maximum value of the calibrated range of the force indicator of the testing machine
N
2
g m/s Local acceleration due to gravity
k Coverage factor used to calculate the expanded uncertainty from the combined
uncertainty
m kg Mass of dead weights used to generate a calibration force
q % Mean relative indication error of the force-measuring system of the testing machine
th
q % The i measurement of the relative indication error of the force-measuring
i
system of the testing machine
q % Allowable value of q for a given class
al
q % The maximum value of q at each calibration point
max
q % The minimum value of q at each calibration point
min
q % Relative indication error determined at a crossover point using force-proving
T1
instrument 1
2 © ISO 2015 – All rights reserved
---------------------- Page: 12 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
Table 1 (continued)
Symbol Unit Meaning
q % Relative indication error determined at a crossover point using force-proving
T2
instrument 2
r N Resolution of the force indicator of the testing machine
u % Combined uncertainty
c
u % Uncertainty component
i
u % Uncertainty component due to repeatability
rep
u % Uncertainty component due to resolution
res
u % Uncertainty component due to the calibration standard used
std
U % Expanded uncertainty
U’ % Expanded reversibility uncertainty
U % Expanded uncertainty using force-proving instrument 1 at a crossover point
T1
U % Expanded uncertainty using force-proving instrument 2 at a crossover point
T2
v % Relative reversibility error of the force-measuring system of the testing machine
3
ρ kg/m Density of air
air
3
ρ kg/m Density of the dead weights
m
5 General inspection of the testing machine
The calibration of the testing machine shall only be carried out if the machine is in good working order.
For this purpose, a general inspection of the machine shall be carried out before calibration of the force-
measuring system of the machine (see Annex A).
NOTE Good metrological practice requires a calibration run prior to any maintenance or adjustments to the
testing machine to determine the “as found” condition of the machine.
Information on the inspection of the loading platens is provided in Annex B. Uncertainty of the
calibration results is discussed in Annex C.
6 Calibration of the force-measuring system of the testing machine
6.1 General
This calibration shall be carried out for each of the force ranges used and with all force indicators in
use. Any accessory devices (e.g. pointer, recorder) that may affect the force-measuring system shall,
where used, be verified in accordance with 6.4.6.
If the testing machine has several force-measuring systems, each system shall be regarded as a separate
testing machine. The same procedure shall be followed for double-piston hydraulic machines.
The calibration shall be carried out using force-proving instruments with the following exception; if
the force to be verified is below the lower limit of the smallest capacity force-proving device used in the
calibration procedure, use known masses.
When more than one force-proving instrument is required to calibrate a force range, the maximum
force applied to the smaller device shall be the same as the minimum force applied to the next force-
proving instrument of higher capacity. When a set of known masses is used to verify forces, the set shall
be considered as a single force-proving instrument.
© ISO 2015 – All rights reserved 3
---------------------- Page: 13 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
The calibration may be carried out with constant indicated forces, F or the calibration can be carried
i
out with constant reference forces, F. Calibration can be carried out using a slowly increasing force for
increasing force levels or a slowly decreasing force for decreasing force levels.
NOTE The word “constant” signifies that the same nominal value of F (or F) is used for the three series of
i
measurements (see 6.4.5).
The instruments used for the calibration shall have a certified traceability to the international
system of units.
The force-proving instrument shall comply with the requirements specified in ISO 376. The class
of the instrument shall be equal to or better than the class for which the testing machine is to be
calibrated. In the case of dead weights, the relative error of the force generated by these weights shall
be within ± 0,1 %.
The exact equation giving the force, F, in newtons, created by the dead weight of mass m, in kilograms, is:
ρ
air
Fm=−g 1 (1)
ρ
m
This force can be calculated using the following approximate formula:
F = mg (2)
The relative error of the force can be calculated from the relative errors of mass and acceleration due to
gravity, using the formula:
ΔF Δm Δg
= + (3)
F m g
6.2 Determination of the resolution
6.2.1 Analogue scale
The thickness of the graduation marks on the scale shall be uniform and the width of the pointer shall
be approximately equal to the width of a graduation mark.
The resolution, r, of the indicator shall be obtained from the ratio between the width of the pointer and
the centre-to-centre distance between two adjacent scale graduation marks (scale interval), multiplied
by the value of force which one scale interval represents. The recommended ratios are 1:2, 1:5 or 1:10, a
spacing of 2,5 mm or greater being required for the determination of one-tenth of a scale division.
6.2.2 Digital scale
The resolution is taken to be one increment of the count of the numerical indicator.
6.2.3 Variation of readings
If the readings vary by more than the value previously calculated for the resolution (with the force-
proving instrument unloaded and with the motor and/or drive mechanism and control on for
determining the sum of all electrical noise), the resolution, r, shall be deemed to be equal to half the
range of fluctuation plus one increment.
NOTE 1 This only determines the resolution due to system noise and does not account for control errors, e.g.
in the case of hydraulic machines.
NOTE 2 For auto-ranging machines, the resolution of the indicator changes as the resolution or gain of the
system changes.
4 © ISO 2015 – All rights reserved
---------------------- Page: 14 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
6.2.4 Unit
The resolution, r, shall be expressed in units of force.
6.3 Prior determination of the relative resolution of the force indicator
The relative resolution, a, of the force indicator is defined by the relationship:
r
a=×100 (4)
F
i
where
r is the resolution defined in 6.2;
F is the force indicated by the force indicator of the testing machine.
i
The relative resolution shall be determined at each calibration point and shall not exceed the values
given in Table 2 for the class of machine being verified.
6.4 Calibration procedure
6.4.1 Alignment of the force-proving instrument
Mount tension force-proving instruments in the machine in such a way as to minimize any effects of
bending (see ISO 376). For the alignment of a force-proving instrument in the compression mode, mount
a platen with a ball nut on the instrument if the machine does not have an incorporated ball cup.
For calibration of tension and compression modes on testing systems that do not use compression
platens for testing, the force proving device may be attached to the testing machine with threaded
studs. In this case, the force proving instrument shall have been calibrated in a similar fashion (i.e.
with threaded studs) and rotation of the force-proving instrument through an angle of 120° is required
between each series of measurements during the calibration of the testing machine.
If the machine has two work areas with a common force application and indicating device, one
calibration could be performed, so that e.g. compression in the upper work area equals tension in the
lower work area, and vice versa. The certificate should carry an appropriate comment.
6.4.2 Temperature compensation
The calibration shall be carried out at an ambient temperature of between 10 °C and 35 °C. The
temperature at which the calibration is carried out shall be noted in the verification report.
A sufficient period of time shall be provided to allow the force-proving instrument to reach a stable
temperature. The temperature of the force-proving instrument shall not change by more than 2 °C from
the beginning to the end of each calibration run. If necessary, temperature corrections shall be applied
to the readings (see ISO 376).
6.4.3 Conditioning of the testing machine and force-proving instrument
Immediately prior to the calibration procedure, the force-proving instrument, in position in the
machine, shall be preloaded at least three times between zero and the maximum force to be measured.
6.4.4 Procedure
Use either or a combination of the following methods:
a) a nominal force, F , indicated by the force indicator of the machine is applied by the machine and
i
the reference force, F, indicated by the force-proving instrument is noted.
© ISO 2015 – All rights reserved 5
---------------------- Page: 15 ----------------------
SIST EN ISO 7500-1:2016
ISO 7500-1:2015(E)
b) a nominal reference force, F, indicated by the force-proving instrument is applied by the machine
and the force, F , indicated by the force indicator of the machine is noted.
i
The word nominal implies that it is not necessary to repeat the exact values of force in each series of
measurements, however they should be approximately the same.
6.4.5 Application of discrete forces
Three series of measurements shall be taken with increasing fo
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.