EN ISO 148-1:2016
(Main)Metallic materials - Charpy pendulum impact test - Part 1: Test method (ISO 148-1:2016)
Metallic materials - Charpy pendulum impact test - Part 1: Test method (ISO 148-1:2016)
ISO 148-1:2016 specifies the Charpy (V-notch and U-notch) pendulum impact test method for determining the energy absorbed in an impact test of metallic materials. This part of ISO 148 does not cover instrumented impact testing, which is specified in ISO 14556.
Annexes B and C are based on ASTM E23 and are used with the permission of ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, USA.
Metallische Werkstoffe - Kerbschlagbiegeversuch nach Charpy - Teil 1: Prüfverfahren (ISO 148-1:2016)
Dieser Teil von ISO 148 gilt für Kerbschlagbiegeversuche nach Charpy (V und U Kerb) für metallische Werk¬stoffe zur Bestimmung der verbrauchten Schlag¬energie. Dieser Teil von ISO 148 gilt nicht für den instrumentierten Kerbschlagbiegeversuch, der in ISO 14556 fest¬gelegt ist.
Matériaux métalliques - Essai de flexion par choc sur éprouvette Charpy - Partie 1: Méthode d'essai (ISO 148-1:2016)
ISO 148-1:2016 spécifie la méthode d'essai de flexion par choc sur éprouvette Charpy (avec entaille en V et avec entaille en U) pour déterminer l'énergie absorbée lors d'un essai de flexion par choc des matériaux métalliques. La présente partie de l'ISO 148 ne couvre pas l'essai de flexion par choc instrumenté, qui est spécifié dans l'ISO 14556.
Les Annexes B et C sont fondées sur l'ASTM E23 et sont utilisées avec la permission de ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, États-Unis.
Kovinski materiali - Udarni preskus po Charpyju - 1. del: Preskusna metoda (ISO 148-1:2016)
Ta del standarda ISO 148 določa preskusno metodo udarnega preskusa po Charpyju (V-zareza in U-zareza) za določanje energije, ki se absorbira pri udarnih preskusih kovinskih materialov. Ta del standarda ISO 148 ne zajema instrumentiranega udarnega preskušanja, ki je podano v standardu ISO 14556.
Dodatka B in C temeljita na standardu ASTM E23 in se uporabljata z dovoljenjem organizacije ASTM.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 148-1:2017
01-februar-2017
1DGRPHãþD
SIST EN ISO 148-1:2010
Kovinski materiali - Udarni preskus po Charpyju - 1. del: Preskusna metoda (ISO
148-1:2016)
Metallic materials - Charpy pendulum impact test - Part 1: Test method (ISO 148-1:2016)
Metallische Werkstoffe - Kerbschlagbiegeversuch nach Charpy - Teil 1: Prüfverfahren
(ISO 148-1:2016)Matériaux métalliques - Essai de flexion par choc sur éprouvette Charpy - Partie 1:
Méthode d'essai (ISO 148-1:2016)Ta slovenski standard je istoveten z: EN ISO 148-1:2016
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
SIST EN ISO 148-1:2017 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 148-1:2017
EN ISO 148-1
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2016
EUROPÄISCHE NORM
ICS 77.040.10 Supersedes EN ISO 148-1:2010
English Version
Metallic materials - Charpy pendulum impact test - Part 1:
Test method (ISO 148-1:2016)
Matériaux métalliques - Essai de flexion par choc sur Metallische Werkstoffe - Kerbschlagbiegeversuch nach
éprouvette Charpy - Partie 1: Méthode d'essai (ISO Charpy - Teil 1: Prüfverfahren (ISO 148-1:2016)
148-1:2016)This European Standard was approved by CEN on 20 August 2016.
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
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 148-1:2016 E
worldwide for CEN national Members.---------------------- Page: 3 ----------------------
SIST EN ISO 148-1:2017
EN ISO 148-1:2016 (E)
Contents Page
European foreword ....................................................................................................................................................... 3
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EN ISO 148-1:2016 (E)
European foreword
This document (EN ISO 148-1:2016) 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 May 2017, and conflicting national standards shall be
withdrawn at the latest by May 2017.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 148-1:2010.
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 148-1:2016 has been approved by CEN as EN ISO 148-1:2016 without any modification.
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SIST EN ISO 148-1:2017
INTERNATIONAL ISO
STANDARD 148-1
Third edition
2016-10-15
Metallic materials — Charpy
pendulum impact test —
Part 1:
Test method
Matériaux métalliques — Essai de flexion par choc sur éprouvette
Charpy —
Partie 1: Méthode d’essai
Reference number
ISO 148-1:2016(E)
ISO 2016
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SIST EN ISO 148-1:2017
ISO 148-1:2016(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, 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
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Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved
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SIST EN ISO 148-1:2017
ISO 148-1:2016(E)
Contents Page
Foreword ........................................................................................................................................................................................................................................iv
1 Scope ................................................................................................................................................................................................................................. 1
2 Normative references ...................................................................................................................................................................................... 1
3 Terms and definitions ..................................................................................................................................................................................... 1
3.1 Definitions pertaining to energy .............................................................................................................................................. 1
3.2 Definitions pertaining to test piece ....................................................................................................................................... 2
4 Symbols and abbreviated terms ........................................................................................................................................................... 2
5 Principles of the test ......................................................................................................................................................................................... 3
6 Test pieces ................................................................................................................................................................................................................... 3
6.1 General ........................................................................................................................................................................................................... 3
6.2 Notch geometry ...................................................................................................................................................................................... 4
6.2.1 V-notch ...................................................................................................................................................................................... 4
6.2.2 U-notch ..................................................................................................................................................................................... 4
6.3 Tolerance of the test pieces .......................................................................................................................................................... 4
6.4 Preparation of the test pieces..................................................................................................................................................... 4
6.5 Marking of the test pieces .............................................................................................................................................................. 4
7 Test equipment....................................................................................................................................................................................................... 4
7.1 General ........................................................................................................................................................................................................... 4
7.2 Installation and verification ........................................................................................................................................................ 5
7.3 Striker ............................................................................................................................................................................................................. 5
8 Test procedure ........................................................................................................................................................................................................ 5
8.1 General ........................................................................................................................................................................................................... 5
8.2 Friction measurement ...................................................................................................................................................................... 5
8.3 Test temperature ................................................................................................................................................................................... 6
8.4 Specimen transfer ................................................................................................................................................................................ 7
8.5 Exceeding machine capacity ....................................................................................................................................................... 7
8.6 Incomplete fracture ............................................................................................................................................................................ 7
8.7 Test piece jamming .............................................................................................................................................................................. 8
8.8 Post-fracture inspection.................................................................................................................................................................. 8
9 Test report ................................................................................................................................................................................................................... 8
9.1 Mandatory information ................................................................................................................................................................... 8
9.2 Optional information ......................................................................................................................................................................... 8
Annex A (informative) Self-centring tongs ..................................................................................................................................................12
Annex B (informative) Lateral expansion.....................................................................................................................................................13
Annex C (informative) Fracture appearance .............................................................................................................................................16
Annex D (informative) Absorbed energy vs. temperature curve and the transition temperature ...19
Annex E (informative) Measurement uncertainty of an absorbed energy value, K ..........................................21
Bibliography .............................................................................................................................................................................................................................29
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SIST EN ISO 148-1:2017
ISO 148-1:2016(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 World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www.iso.org/iso/foreword.html.
The committee responsible for this document is ISO/TC 164, Mechanical testing of metals, Subcommittee
SC 4, Toughness testing — Fracture (F), Pendulum (P), Tear (T).This third edition cancels and replaces the second edition (ISO 148-1:2009), which has been technically
revised.ISO 148 consists of the following parts, under the general title Metallic materials — Charpy pendulum
impact test:— Part 1: Test method
— Part 2: Verification of testing machines
— Part 3: Preparation and characterization of Charpy V-notch test pieces for indirect verification of
pendulum impact machinesiv © ISO 2016 – All rights reserved
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SIST EN ISO 148-1:2017
INTERNATIONAL STANDARD ISO 148-1:2016(E)
Metallic materials — Charpy pendulum impact test —
Part 1:
Test method
1 Scope
This part of ISO 148 specifies the Charpy (V-notch and U-notch) pendulum impact test method for
determining the energy absorbed in an impact test of metallic materials. This part of ISO 148 does not
cover instrumented impact testing, which is specified in ISO 14556.Annexes B and C are based on ASTM E23 and are used with the permission of ASTM International, 100
Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, USA.2 Normative references
The following referenced documents, in whole or in part, are normatively referenced in this document
and are indispensable for the application of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including any
amendments) applies.ISO 148-2, Metallic materials — Charpy pendulum impact test — Part 2: Verification of testing machines
ISO 286-1, Geometrical product specifications (GPS) — ISO code system for tolerances on linear sizes —
Part 1: Basis of tolerances, deviations and fits3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Definitions pertaining to energy
3.1.1
initial potential energy
potential energy
potential energy of the pendulum hammer prior to its release for the impact test, as determined by
direct verification3.1.2
absorbed energy
energy required to break a test piece with a pendulum impact testing machine, after correction for
frictionNote 1 to entry: The letter V or U is used to indicate the notch geometry, that is: KV or KU. The number 2 or 8 is
used as a subscript to indicate the radius of the striker, for example KV .3.1.3
nominal initial potential energy
nominal energy
energy assigned by the manufacturer of the pendulum impact testing machine
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SIST EN ISO 148-1:2017
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3.2 Definitions pertaining to test piece
3.2.1
width
distance between the notched face and the opposite face
Note 1 to entry: See Figure 1.
Note 2 to entry: In previous versions of the ISO 148 series (prior to 2016), the distance between the notched face
and the opposite face was specified as “height”. Changing this dimension to “width” makes this part of ISO 148
consistent with the terminology used in other ISO fracture standards.3.2.2
thickness
dimension perpendicular to the width and parallel to the notch
Note 1 to entry: See Figure 1.
Note 2 to entry: In previous versions of the ISO 148 series (prior to 2016), the dimension perpendicular to the
width that is parallel to the notch was specified as “width”. Changing this dimension to “thickness” makes this
part of ISO 148 consistent with the terminology used in other ISO fracture standards.
3.2.3length
largest dimension perpendicular to the notch
Note 1 to entry: See Figure 1.
4 Symbols and abbreviated terms
The symbols and designations applicable to this part of ISO 148 are indicated in Tables 1 and 2, and are
illustrated in Figure 2.Table 1 — Symbols and their unit and designation
Symbol Unit Designation
B mm thickness of test piece
α ° angle of fall of the pendulum
β J or ° angle of rise when the machine is operated in the normal manner without a test
piece in positionβ J or ° angle of rise when the machine is operated in the normal manner without a test
piece in position and without resetting the indication mechanismL mm length of test piece
LE mm lateral expansion
K J absorbed energy (expressed as KV , KV , KU , KU , to identify specific notch geome-
2 8 2 8tries and the radius of the striking edge)
K J or ° indicated absorbed energy when the machine is operated in the normal manner
without a test piece in positionK J or ° indicated absorbed energy when the machine is operated in the normal manner
without a test piece in position and without resetting the indication mechanismK J or ° nominal initial potential energy
K J initial potential energy (potential energy)
KV J absorbed energy for a V-notch test piece using a 2 mm striker
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SIST EN ISO 148-1:2017
ISO 148-1:2016(E)
Table 1 (continued)
Symbol Unit Designation
KV J absorbed energy for a V-notch test piece using a 8 mm striker
KU J absorbed energy for a U-notch test piece using a 2 mm striker
KU J absorbed energy for a U-notch test piece using an 8 mm striker
M N·m moment equal to the product F·l
p J absorbed energy loss caused by pointer friction
p’ J absorbed energy loss caused by bearing friction and air resistance
p J correction of absorbed energy losses for an angle of rise β
SFA % shear fracture appearance
T °C transition temperature
W mm width of test piece
transition temperature defined at a specific value of absorbed energy;
T °C
t27
for example, 27 J
transition temperature defined at a particular percentage of the absorbed energy of
T °Ct50 %US
the upper shelf; for example, 50 %
transition temperature defined at a particular proportion of shear fracture;
T °C
t50 %SFA
for example, 50 %
transition temperature defined at a particular amount of lateral expansion;
T °C
t0,9
for example, 0,9 mm
5 Principles of the test
This test consists of breaking a notched test piece with a single blow from a swinging pendulum, under
the conditions defined in Clauses 6, 7 and 8. The notch in the test piece has a specified geometry and
is located in the middle between two supports, opposite to the location which is impacted in the test.
The energy absorbed in the impact test, the lateral expansion and the shear fracture appearance are
normally determined.Because the impact values of many metallic materials vary with temperature, tests shall be carried out
at a specified temperature. When this temperature is other than ambient, the test piece shall be heated
or cooled to that temperature, under controlled conditions.The Charpy pendulum impact test is often used in routine, high-throughput pass/fail acceptance tests
in industrial settings. For these tests, it may not be important whether the test sample is completely
broken, partially broken, or simply plastically deformed and dragged through the anvils. In research,
design, or academic settings, the measured energy values are studied in more detail, in which case it
can be highly relevant whether the sample is broken or not.It is important to note that not all Charpy pendulum impact test results can be directly compared. For
example, the test can be performed with hammers having strikers with different radii, or with different
[7]test piece shapes. Tests performed with different strikers can give different results, and test results
obtained with differently shaped test pieces can as well. This is why not only the adherence to ISO 148
but also a clear and complete reporting of the type of instrument, the test piece and the details of the
post-test test pieces are crucial for comparability of results.6 Test pieces
6.1 General
The standard test piece shall be 55 mm long and of square section, with 10 mm sides. In the centre of
the length, there shall be either a V-notch or a U-notch, as described in 6.2.1 and 6.2.2, respectively.
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SIST EN ISO 148-1:2017
ISO 148-1:2016(E)
If the standard test piece cannot be obtained from the material, one of the subsize test pieces, having a
thickness of 7,5 mm, 5 mm or 2,5 mm (see Figure 2 and Table 2), shall be used, if not otherwise specified.
NOTE 1 Direct comparison of results is only of significance when made between test pieces of the same form
and dimensions.NOTE 2 For low energies, the use of shims to better position subsize test pieces relative to the centre of
strike is important to avoid excess energy absorption by the pendulum. For high energies, this might not be as
important. Shims can be placed on or under the test piece supports, with the result that the mid-thickness of
the specimen is 5 mm above the 10 mm supports. Shims can be temporarily fixed to the supports using tape or
another means.When a heat-treated material is being evaluated, the test piece shall be finish-machined and notched
after the final heat treatment, unless it can be demonstrated that machining before heat treatment does
not affect test results.6.2 Notch geometry
The notch shall be carefully prepared so that the root radius of the notch is free of machining marks
which could affect the absorbed energy.The plane of symmetry of the notch shall be perpendicular to the longitudinal axis of the test piece
(see Figure 2).6.2.1 V-notch
The V-notch shall have an included angle of 45°, a depth of 2 mm and a root radius of 0,25 mm
[see Figure 2 a) and Table 2].6.2.2 U-notch
The U-notch shall have a depth of 5 mm (unless otherwise specified) and a root radius of 1 mm
[see Figure 2 b) and Table 2].6.3 Tolerance of the test pieces
The tolerances on the specified test piece and notch dimensions are shown in Figure 2 and Table 2.
6.4 Preparation of the test piecesPreparation shall be executed in such a way that any alteration of the test piece, for example due to
heating or cold working, is minimized.6.5 Marking of the test pieces
The test piece may be marked on any face not in contact with supports, anvils or striker and at a position
where plastic deformation and surface discontinuities caused by marking do not affect the absorbed
energy (see 8.8).7 Test equipment
7.1 General
The measurements of the instrument and test piece details shall be traceable to national or international
standards. Equipment used for measurements shall be calibrated within suitable intervals.
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SIST EN ISO 148-1:2017
ISO 148-1:2016(E)
7.2 Installation and verification
The testing machine shall be installed and verified in accordance with ISO 148-2.
7.3 StrikerThe striker geometry shall be specified as being either the 2 mm striker or the 8 mm striker. It is
recommended that the radius on the striker be shown as a subscript as follows: KV or KV and KU or
2 8 2KU .
Reference shall be made to the product specification for striker geometry guidance.
[7]NOTE Tests carried out with 2 mm and 8 mm strikers can give different results.
8 Test procedure
8.1 General
The test piece shall lie squarely against the anvils of the testing machine, with the plane of symmetry
of the notch within 0,5 mm of the mid-plane between the anvils. It shall be struck by the striker in the
plane of symmetry of the notch and on the side opposite the notch (see Figure 1).
8.2 Friction measurementThe energy absorbed by friction shall be checked on every testing day prior to the first test. The friction
losses may be estimated as explained below, but other methods may also be applied.
NOTE The energy absorbed by friction includes, but is not limited to, air resistance, bearing friction and the
friction of the indicating pointer. Increases in friction on a machine can influence the measure of absorbed energy.
8.2.1 To determine the loss caused by pointer friction the machine is operated in the normal manner,
but without a test piece in position, and the angle of rise, β , or energy reading, K , is noted. A second
1 1test is then carried out without resetting the indication pointer and the new angle of rise, β , or energy
reading, K , is noted. Thus, the loss due to friction in the indicating pointer during the rise is equal to
p = M(cos β − cos β) (1)1 2
when the scale is graduated in degrees, or
p = K − K (2)
1 2
when the scale is graduated in energy units.
NOTE For machines without a pointer, this friction measurement is not necessary.
8.2.2 The procedure to determine the losses caused by bearing friction and air resistance for one half
swing is as follows.After determining β or K , the pendulum is returned to its initial position. Without resetting the
2 2indicating mechanism, release the pendulum without shock and vibration and permit it to swing 10
half swings. After the pendulum starts its 11th half swing, move the indicating mechanism to about
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SIST EN ISO 148-1:2017
ISO 148-1:2016(E)
5 % of the scale-range capacity and record the value as β or K . The losses by bearing friction and air
3 3resistance for one half swing are equal to
p′ = 1/10 M(cos β − cos β) (3)
3 2
when the scale is graduated in degrees, or
p′ = 1/10 (K − K) (4)
3 2
when the scale is graduated in energy units.
The number of swings can be changed at the discretion of machine users, and p’ should be corrected on
account of the applied number of swings.NOTE 1 If it is required to take into account these losses in an actual test giving an angle of rise, β, the quantity
can be subtracted from the value of the absorbed energy.αβ+
pp=+ p (5)
β αβ+
1 2
Because β and β are nearly equal to α, the angle of fall, for practical purposes Formula (5) can be
1 2reduced to:
αβ+
pp=+ p (6)
α 2α
For machines graduated in energy units, the value of β can be calculated as follows:
β = arccos[1 − 1/M(K − K)] (7)P T
The total friction loss, p + p′, so measured, shall not exceed 0,5 % of the nominal energy, K . If it does,
and it is not possible to bring the friction loss within the tolerance by reducing the
...
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