Metallic materials - Charpy pendulum impact test - Part 2: Verification of testing machines (ISO 148-2:2008)

This part of ISO 148 covers the verification of the constructional elements of pendulum-type impact testing machines. It is applicable to machines with 2 mm or 8 mm strikers used for pendulum impact tests carried out, for instance, in accordance with ISO 148-1. It can analogously be applied to pendulum impact testing machines of various capacities and of different design. Impact machines used for industrial, general or research laboratory testing of metallic materials in accordance with this part of ISO 148 are referred to as industrial machines. Those with more stringent requirements are referred to as reference machines. Specifications for the verification of reference machines are found in ISO 148-3. This part of ISO 148 describes two methods of verification. a) The direct method, which is static in nature, involves measurement of the critical parts of the machine to ensure that it meets the requirements of this part of ISO 148. Instruments used for the verification and calibration are traceable to national standards. Direct methods are used when a machine is being installed or repaired, or if the indirect method gives a non-conforming result. b) The indirect method, which is dynamic in nature, uses reference test pieces to verify points on the measuring scale. A pendulum impact testing machine is not in compliance with this part of ISO 148 until it has been verified by both the direct and indirect methods and meets the requirements of Clauses 6 and 7. The requirements for the reference test pieces are found in ISO 148-3. This part of ISO 148 takes into account the total energy absorbed in fracturing the test piece using an indirect method. This total absorbed energy consists of - the energy needed to break the test piece itself, and - the internal energy losses of the pendulum impact testing machine performing the first half-cycle swing from the initial position.

Metallische Werkstoffe - Kerbschlagbiegeversuch nach Charpy - Teil 2: Prüfung der Prüfmaschinen (Pendelschlagwerke) (ISO 148-2:2008)

In diesem Teil von ISO 148 wird die Prüfung der einzelnen Teile eines Pendelschlagwerks festgelegt. Er gilt für Pendelschlagwerke mit 2 mm Hämmern oder mit 8 mm Hämmern, die z. B. für Kerbschlagbiegeversuche nach ISO 148 1 angewendet werden.
Sinngemäß ist dieser Teil von ISO 148 auch auf Pendelschlagwerke anderer Bauarten mit einem anderen Arbeitsvermögen anwendbar.
Pendelschlagwerke, die für die Prüfung metallischer Werkstoffe nach dem vorliegenden Teil von ISO 148 für betriebliche, für allgemeine und für Forschungszwecke vorgesehen sind, werden als Betriebs Pendelschlagwerke bezeichnet. Pendelschlagwerke, für die strengere Anforderungen gelten, werden als Referenz-Pendelschlagwerke bezeichnet. Festlegungen für die Prüfung von Referenz Pendelschlagwerken sind in ISO 148 3 enthalten.
In diesem Teil von ISO 148 werden zwei Verfahren zur Prüfung der Prüfmaschinen beschrieben:
a)   Das direkte Verfahren, bei dem eine statische Einzelprüfung der kritischen Teile des Pendelschlagwerks unter Einbeziehung von Messungen durchgeführt wird um sicherzustellen, dass die Anforderungen dieses Teils von ISO 148 erfüllt werden. Die für Prüfung und Kalibrierung eingesetzten Geräte müssen auf nationale Normen rückführbar sein. Das direkte Verfahren muss angewendet werden, nachdem eine Prüfmaschine aufgestellt oder repariert wurde oder wenn nach dem indirekten Verfahren fehlerhafte Ergebnisse ermittelt werden;
b)   das indirekte Verfahren, bei dem eine dynamische Prüfung an Referenzproben durchgeführt wird, um die Punkte auf der Messskala zu überprüfen.
Ein Pendelschlagwerk entspricht erst dann diesem Teil von ISO 148, wenn Prüfungen sowohl nach dem direkten als auch nach dem indirekten Verfahren durchgeführt wurden (siehe Abschnitt 7).
Die Anforderungen an die Referenzproben werden in ISO 148 3 festgelegt.

Matériaux métalliques - Essai de flexion par choc sur éprouvette Charpy - Partie 2: Vérification des machines d'essai (mouton-pendule) (ISO 148-2:2008)

L'ISO 148-2:2008 traite de la vérification des éléments des machines d'essai de flexion par choc (moutons-pendules). Elle s'applique aux machines ayant des couteaux de 2 mm ou de 8 mm utilisées pour les essais de flexion par choc effectués par exemple conformément à l'ISO 148-1.
Elle peut s'appliquer de manière analogue aux moutons-pendules de capacités ou de conception différentes.
Les machines de choc utilisées pour les essais des matériaux métalliques par des laboratoires industriels, généralistes ou de recherche conformément à l'ISO 148-2:2008 sont qualifiées de machines industrielles. Celles répondant à des exigences plus contraignantes sont qualifiées de machines de référence. Les exigences relatives à la vérification des machines de référence sont fixées dans l'ISO 148-3.
L'ISO 148-2:2008 décrit deux méthodes de vérification: une méthode directe et une méthode indirecte.

Kovinski materiali - Udarni preskus po Charpyju - 2. del: Preverjanje preskusnih naprav (ISO 148-2:2008)

General Information

Status
Withdrawn
Publication Date
25-Feb-2009
Withdrawal Date
08-Feb-2017
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
09-Feb-2017
Due Date
04-Mar-2017
Completion Date
09-Feb-2017

Relations

Buy Standard

Standard
EN ISO 148-2:2009
English language
46 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day
Draft
prEN ISO 148-2:2006
English language
25 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 148-2:2009
01-april-2009
1DGRPHãþD
SIST EN 10045-2:1996
SIST EN 10045-2:1996/AC1:1997
Kovinski materiali - Udarni preskus po Charpyju - 2. del: Preverjanje preskusnih
naprav (ISO 148-2:2008)
Metallic materials - Charpy pendulum impact test - Part 2: Verification of testing
machines (ISO 148-2:2008)
Metallische Werkstoffe - Kerbschlagbiegeversuch nach Charpy - Teil 2: Prüfung der
Prüfmaschinen (Pendelschlagwerke) (ISO 148-2:2008)
Matériaux métalliques - Essai de flexion par choc sur éprouvette Charpy - Partie 2:
Vérification des machines d'essai (mouton-pendule) (ISO 148-2:2008)
Ta slovenski standard je istoveten z: EN ISO 148-2:2008
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
SIST EN ISO 148-2:2009 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------

SIST EN ISO 148-2:2009

---------------------- Page: 2 ----------------------

SIST EN ISO 148-2:2009
EUROPEAN STANDARD
EN ISO 148-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2008
ICS 77.040.10

English Version
Metallic materials - Charpy pendulum impact test - Part 2:
Verification of testing machines (ISO 148-2:2008)
Matériaux métalliques - Essai de flexion par choc sur Metallische Werkstoffe - Kerbschlagbiegeversuch nach
éprouvette Charpy - Partie 2: Vérification des machines Charpy - Teil 2: Prüfung der Prüfmaschinen
d'essai (mouton-pendule) (ISO 148-2:2008) (Pendelschlagwerke) (ISO 148-2:2008)
This European Standard was approved by CEN on 19 November 2008.
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 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 Management Centre has the same status as the
official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, 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 FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 148-2:2008: E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------

SIST EN ISO 148-2:2009
EN ISO 148-2:2008 (E)
Contents Page
Foreword .3

2

---------------------- Page: 4 ----------------------

SIST EN ISO 148-2:2009
EN ISO 148-2:2008 (E)
Foreword
This document (EN ISO 148-2:2008) has been prepared by Technical Committee ISO/TC 164 "Mechanical
testing of metals" in collaboration with Technical Committee ECISS/TC 1 "Steel - Mechanical testing" 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 2009, and conflicting national standards shall be withdrawn at
the latest by June 2009.
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.
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, 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 the United Kingdom.
Endorsement notice
The text of ISO 148-2:2008 has been approved by CEN as a EN ISO 148-2:2008 without any modification.

3

---------------------- Page: 5 ----------------------

SIST EN ISO 148-2:2009

---------------------- Page: 6 ----------------------

SIST EN ISO 148-2:2009

INTERNATIONAL ISO
STANDARD 148-2
Second edition
2008-12-15

Metallic materials — Charpy pendulum
impact test —
Part 2:
Verification of testing machines
Matériaux métalliques — Essai de flexion par choc sur éprouvette
Charpy —
Partie 2: Vérification des machines d'essai (mouton-pendule)




Reference number
ISO 148-2:2008(E)
©
ISO 2008

---------------------- Page: 7 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.


COPYRIGHT PROTECTED DOCUMENT


©  ISO 2008
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland

ii © ISO 2008 – All rights reserved

---------------------- Page: 8 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 2
3 Terms and definitions. 2
3.1 Definitions pertaining to the machine . 2
3.2 Definitions pertaining to energy. 3
3.3 Definitions pertaining to test pieces. 4
4 Symbols and abbreviated terms . 4
5 Testing machine. 6
6 Direct verification. 6
6.1 General. 6
6.2 Foundation/installation . 6
6.3 Machine framework . 6
6.4 Pendulum. 7
6.5 Anvil and supports . 11
6.6 Indicating equipment. 11
7 Indirect verification by use of reference test pieces. 12
7.1 Reference test pieces used . 12
7.2 Absorbed energy levels . 12
7.3 Requirements for reference test pieces . 12
7.4 Limited direct verification . 12
7.5 Bias and repeatability. 13
8 Frequency of verification . 13
9 Verification report. 14
9.1 General. 14
9.2 Direct verification. 14
9.3 Indirect verification. 14
10 Uncertainty . 14
Annex A (informative) Measurement uncertainty of the result of the indirect verification of a
Charpy pendulum impact machine. 21
Annex B (informative) Measurement uncertainty of the results of the direct verification of a
Charpy pendulum impact testing machine . 25
Annex C (informative) Direct method of verifying the geometric properties of pendulum impact
testing machines using a jig. 31
Bibliography . 38

© ISO 2008 – All rights reserved iii

---------------------- Page: 9 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(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.
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
adopted 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
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 148-2 was prepared by Technical Committee ISO/TC 164, Mechanical testing of metals, Subcommittee
SC 4, Toughness testing — Fracture (F), Pendulum (P), Tear (T).
This second edition cancels and replaces the first edition (ISO 148-2:1998), 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 machines

iv © ISO 2008 – All rights reserved

---------------------- Page: 10 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
Introduction
The suitability of a pendulum impact testing machine for acceptance testing of metallic materials has usually
been based on a calibration of its scale and verification of compliance with specified dimensions, such as the
shape and spacing of the anvils supporting the specimen. The scale calibration is commonly verified by
measuring the mass of the pendulum and its elevation at various scale readings. This procedure for
evaluation of machines had the distinct advantage of requiring only measurements of quantities that could be
traced to national standards. The objective nature of these traceable measurements minimized the necessity
for arbitration regarding the suitability of the machines for material acceptance tests.
However, sometimes two machines that had been evaluated by the direct-verification procedures described
above, and which met all dimensional requirements, were found to give significantly different impact values
when testing test pieces of the same material. This difference was commercially important when values
obtained using one machine met the material specification, while the values obtained using the other machine
did not. To avoid such disagreements, some purchasers of materials added the requirement that all pendulum
impact testing machines used for acceptance testing of material sold to them must be indirectly verified by
testing reference test pieces supplied by them. A machine was considered acceptable only if the values
obtained using the machine agreed, within specified limits, with the value furnished with the reference test
pieces.

© ISO 2008 – All rights reserved v

---------------------- Page: 11 ----------------------

SIST EN ISO 148-2:2009

---------------------- Page: 12 ----------------------

SIST EN ISO 148-2:2009
INTERNATIONAL STANDARD ISO 148-2:2008(E)

Metallic materials — Charpy pendulum impact test —
Part 2:
Verification of testing machines
1 Scope
This part of ISO 148 covers the verification of the constructional elements of pendulum-type impact testing
machines. It is applicable to machines with 2 mm or 8 mm strikers used for pendulum impact tests carried out,
for instance, in accordance with ISO 148-1.
It can analogously be applied to pendulum impact testing machines of various capacities and of different
design.
Impact machines used for industrial, general or research laboratory testing of metallic materials in accordance
with this part of ISO 148 are referred to as industrial machines. Those with more stringent requirements are
referred to as reference machines. Specifications for the verification of reference machines are found in
ISO 148-3.
This part of ISO 148 describes two methods of verification.
a) The direct method, which is static in nature, involves measurement of the critical parts of the machine to
ensure that it meets the requirements of this part of ISO 148. Instruments used for the verification and
calibration are traceable to national standards. Direct methods are used when a machine is being
installed or repaired, or if the indirect method gives a non-conforming result.
b) The indirect method, which is dynamic in nature, uses reference test pieces to verify points on the
measuring scale.
A pendulum impact testing machine is not in compliance with this part of ISO 148 until it has been verified by
both the direct and indirect methods and meets the requirements of Clauses 6 and 7.
The requirements for the reference test pieces are found in ISO 148-3.
This part of ISO 148 takes into account the total energy absorbed in fracturing the test piece using an indirect
method. This total absorbed energy consists of
⎯ the energy needed to break the test piece itself, and
⎯ the internal energy losses of the pendulum impact testing machine performing the first half-cycle swing
from the initial position.
NOTE Internal energy losses are due to
⎯ air resistance, friction of the bearings of the rotation axis and of the indicating pointer of the pendulum which can
be determined by the direct method (see 6.4.5), and
⎯ shock of the foundation, vibration of the frame and pendulum for which no suitable measuring methods and
apparatus have been developed.
© ISO 2008 – All rights reserved 1

---------------------- Page: 13 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
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 references, the latest edition of the referenced
document (including any amendments) applies.
ISO 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method
ISO 148-3, Metallic materials — Charpy pendulum impact test — Part 3: Preparation and characterization of
Charpy V-notch test pieces for indirect verification of pendulum impact machines
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Definitions pertaining to the machine
3.1.1
anvil
portion of the machine that serves to properly position the test piece for impact with respect to the striker and
the test piece supports, and supports the test piece under the force of the strike
3.1.2
base
that part of the framework of the machine located below the horizontal plane of the supports
3.1.3
centre of percussion
that point in a body at which, on striking a blow, the percussive action is the same as if the whole mass of the
body were concentrated at the point
NOTE When a simple pendulum delivers a blow along a horizontal line passing through the centre of percussion,
there is no resulting horizontal reaction at the axis of rotation.
See Figure 4.
3.1.4
centre of strike
that point on the striking edge of the pendulum at which, in the free hanging position of the pendulum, the
vertical edge of the striker meets the upper horizontal plane of a test piece of half standard height (i.e. 5 mm)
or equivalent gauge bar resting on the test piece supports
See Figure 4.
3.1.5
industrial machine
pendulum impact machine used for industrial, general, or most research-laboratory testing of metallic
materials
NOTE 1 These machines are not used to establish reference values.
NOTE 2 Industrial machines are verified using the procedures described in this part of ISO 148.
3.1.6
reference machine
pendulum impact testing machine used to determine certified values for batches of reference test pieces
2 © ISO 2008 – All rights reserved

---------------------- Page: 14 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
3.1.7
striker
portion of the pendulum that contacts the test piece
NOTE The edge that actually contacts the test piece has a radius of 2 mm (the 2 mm striker) or a radius of 8 mm (the
8 mm striker).
See Figure 2.
3.1.8
test piece supports
portion of the machine that serves to properly position the test piece for impact with respect to the centre of
percussion of the pendulum, the striker and the anvils
See Figures 2 and 3.
3.2 Definitions pertaining to energy
3.2.1
total absorbed energy
K
T
total absorbed energy required to break a test piece with a pendulum impact testing machine, which is not
corrected for any losses of energy
NOTE It is equal to the difference in the potential energy from the starting position of the pendulum to the end of the
first half swing during which the test piece is broken (see 6.3).
3.2.2
initial potential energy
potential energy
K
P
difference between the potential energy of the pendulum hammer prior to its release for the impact test, and
the potential energy of the pendulum hammer at the position of impact, as determined by direct verification
NOTE See 6.4.2.
3.2.3
absorbed energy
K
energy required to break a test piece with a pendulum impact testing machine, after correction for friction
NOTE 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 striker radius, for example KV .
2
3.2.4
calculated energy
K
calc
energy calculated from values of angle, length, and force measured during direct verification
3.2.5
nominal initial potential energy
nominal energy
K
N
energy assigned by the manufacturer of the pendulum impact testing machine
3.2.6
indicated absorbed energy
K
S
energy indicated by the display/dial of the testing machine, which may or may not need to be corrected for
friction to determine absorbed energy, K
© ISO 2008 – All rights reserved 3

---------------------- Page: 15 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
3.2.7
reference absorbed energy
K
R
certified value of absorbed energy assigned to the test pieces used to verify the performance of pendulum
impact machines
3.3 Definitions pertaining to test pieces
3.3.1
height
distance between the notched face and the opposite face
3.3.2
width
dimension perpendicular to the height that is parallel to the notch
3.3.3
length
largest dimension perpendicular to the notch
3.3.4
reference test piece
impact test piece used to verify the suitability of pendulum impact testing machines by comparing the
indicated absorbed energy measured by that machine to the reference absorbed energy associated with the
test pieces
NOTE Reference test pieces are prepared in accordance with ISO 148-3.
4 Symbols and abbreviated terms
For the purposes of this document, the symbols and abbreviated terms given in Table 1 are applicable.
Table 1 — Symbols/abbreviated terms and their designations and units
Symbol/
abbreviated Unit Designation
a
term
B J Bias of the pendulum impact machine as determined through indirect verification
V
b J Repeatability
F N Force exerted by the pendulum when measured at a distance of l
2
F N Force exerted by the pendulum due to gravity
g
2
g Acceleration due to gravity
m/s
GUM — Guide to the expression of uncertainty in measurement
h m Height of fall of pendulum
H m Height of rise of pendulum
1
ISO — International Organization for Standardization
KV J Absorbed energy as measured in accordance with ISO 148 on a V-notched sample
KV J Certified KV value of the reference material used in the indirect verification
R
KV J Mean KV value of the reference test pieces tested for indirect verification
V
K J Nominal initial potential energy (nominal energy)
N
K J Initial potential energy (potential energy)
P
K J Reference absorbed energy of a set of Charpy reference test pieces
R
4 © ISO 2008 – All rights reserved

---------------------- Page: 16 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
Table 1 (continued)
Symbol/
abbreviated Unit Designation
a
term
Absorbed energy (expressed as KV , KV , KU , KU , to identify specific notch
2 8 2 8
K J
geometries and striker radii)
K J Total absorbed energy
T
K J Indicated absorbed energy
S
K J Calculated energy
calc
Indicated absorbed energy or angle of rise when the machine is operated in the normal
K or b J or degree
1 1
manner without a test piece in position
Indicated absorbed energy or angle of rise when the machine is operated in the normal
K or b J or degree
2 2
manner without a test piece in position and without resetting the indication mechanism
Indicated absorbed energy or angle of rise after 11 half swings when the machine is
K or b J or degree operated in the normal manner without a test piece in position and without resetting the
3 3
indication mechanism
Distance to centre of test piece (centre of striker) from the axis of rotation (length of
l m
pendulum)
l m Distance to the centre of percussion from the axis of rotation
1
l m Distance to the point of application of the force F from the axis of rotation
2
M N·m Moment equal to the product Fl
2
Number of reference samples tested for the indirect verification of a pendulum impact
n —
V
testing machine
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 swing b
b
r J Resolution of the pendulum scale
RM — Reference material
s J Standard deviation of the KV values obtained on n reference samples
V V
S J Bias in the scale mechanism
t s Period of the pendulum
T s Total time for 100 swings of the pendulum
T s Maximum value of T
max
T s Minimum value of T
min
uK()V J Standard uncertainty of KV
V
V
u(B ) J Standard uncertainty contribution from bias

V
u(F) J Standard uncertainty of the measured force, F
u(F ) J Standard uncertainty of the force transducer
std
u(r) J Standard uncertainty contribution from resolution
Standard uncertainty of the certified value of the reference material used for the
u J
RM
indirect verification
u J Standard uncertainty of the indirect verification result
V
a degree Angle of fall of the pendulum
b degree Angle of rise of the pendulum
ν — Degrees of freedom corresponding to u(B )
B V
ν — Degrees of freedom corresponding to u
V V
ν — Degrees of freedom corresponding to u
RM RM
a
See Figure 4.
© ISO 2008 – All rights reserved 5

---------------------- Page: 17 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
5 Testing machine
A pendulum impact testing machine consists of the following parts (see Figures 1 to 3):
a) foundation/installation;
b) machine framework — the structure supporting the pendulum, excluding the foundation;
c) pendulum, including the hammer;
d) anvils and supports (see Figures 2 and 3);
e) indicating equipment for the absorbed energy (e.g. scale and friction pointer or electronic readout device).
6 Direct verification
6.1 General
Direct verification of the machine involves the inspection of the following items:
a) foundation/installation;
b) machine framework;
c) pendulum, including the hammer and the striker;
d) anvils and supports;
e) indicating equipment.
6.2 Foundation/installation
6.2.1 The foundation to which the machine is fixed and the method(s) of fixing the machine to the
foundation are of utmost importance.
6.2.2 Inspection of the machine foundation can usually not be made once the machine has been installed;
thus, documentation made at the time of installation shall be produced to provide assurance that the mass of
the foundation is not less than 40 times that of the pendulum.
6.2.3 Inspection of the installed machine shall consist of the following:
a) ensuring that the bolts are torqued to the value specified by the machine manufacturer. The torque value
shall be noted in the document provided by the manufacturer of the machine (see 6.2.1). If other
mounting arrangements are used or selected by an end user, equivalency shall be demonstrated;
b) ensuring that the machine is not subject to external vibrations transmitted through the foundation at the
time of the impact test.
NOTE This can be accomplished, for example, by placing a small container of water on any convenient location on
the machine framework. The absence of ripples on the water surface indicates that this requirement has been met.
6.3 Machine framework
6.3.1 Inspection of the machine framework (see Figure 1) shall consist of determining the following items:
a) free position of the pendulum;
b) location of the pendulum in relation to the supports;
c) transverse and radial play of the pendulum bearings;
d) clearance between the hammer and the framework.
6 © ISO 2008 – All rights reserved

---------------------- Page: 18 ----------------------

SIST EN ISO 148-2:2009
ISO 148-2:2008(E)
Machines manufactured after the original publication date of t
...

SLOVENSKI oSIST prEN ISO 148-2:2006

PREDSTANDARD
julij 2006
Kovinski materiali – Nihajni udarni preskus po Charpyju – 2. del: Preverjanje
preskusnih naprav (ISO/DIS 148-2:2006)
Metallic materials - Charpy pendulum impact test - Part 2: Verification of testing
machines (ISO/DIS 148-2:2006)
ICS 77.040.10 Referenčna številka
oSIST prEN ISO 148-2:2006(en)
©  Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno

---------------------- Page: 1 ----------------------
EUROPEAN STANDARD
DRAFT
prEN ISO 148-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2006
ICS 77.040.10

English Version
Metallic materials - Charpy pendulum impact test - Part 2:
Verification of testing machines (ISO/DIS 148-2:2006)
Matériaux métalliques - Essai de flexion par choc sur
éprouvette Charpy - Partie 2: Vérification des machines
d'essai (mouton-pendule) (ISO/DIS 148-2:2006)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
ECISS/TC 1.
If this draft becomes a European Standard, 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.
This draft European Standard was established by CEN 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 Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, 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.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 148-2:2006: E
worldwide for CEN national Members.

---------------------- Page: 2 ----------------------
prEN ISO 148-2:2006 (E)




Foreword

This document (prEN ISO 148-2:2006) has been prepared by Technical Committee ISO/TC
164 "Mechanical testing of metals" in collaboration with Technical Committee ECISS/TC 1
"Steel - Mechanical testing", the secretariat of which is held by AFNOR.

This document is currently submitted to the parallel Enquiry.


Endorsement notice

The text of ISO 148-2:2006 has been approved by CEN as prEN ISO 148-2:2006 without any
modifications.

2

---------------------- Page: 3 ----------------------
DRAFT INTERNATIONAL STANDARD ISO/DIS 148-2
ISO/TC 164/SC 4 Secretariat: ANSI
Voting begins on: Voting terminates on:
2006-05-11 2006-10-11
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
Metallic materials — Charpy pendulum impact test —
Part 2:
Verification of testing machines
Matériaux métalliques — Essai de flexion par choc sur éprouvette Charpy —
Partie 2: Vérification des machines d'essai (mouton-pendule)
[Revision of first edition (ISO 148-2:1998)]
ICS 77.040.10

ISO/CEN PARALLEL ENQUIRY
The CEN Secretary-General has advised the ISO Secretary-General that this ISO/DIS covers a subject
of interest to European standardization. In accordance with the ISO-lead mode of collaboration as
defined in the Vienna Agreement, consultation on this ISO/DIS has the same effect for CEN
members as would a CEN enquiry on a draft European Standard. Should this draft be accepted, a
final draft, established on the basis of comments received, will be submitted to a parallel two-month FDIS
vote in ISO and formal vote in CEN.
To expedite distribution, this document is circulated as received from the committee secretariat.
ISO Central Secretariat work of editing and text composition will be undertaken at publication
stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.
THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
© International Organization for Standardization, 2006

---------------------- Page: 4 ----------------------
ISO/DIS 148-2
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall
not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the
unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.
Copyright notice
This ISO document is a Draft International Standard and is copyright-protected by ISO. Except as permitted
under the applicable laws of the user's country, neither this ISO draft nor any extract from it may be
reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, photocopying,
recording or otherwise, without prior written permission being secured.
Requests for permission to reproduce should be addressed to either ISO at the address below or ISO's
member body in the country of the requester.
ISO copyright office
Case postale 56  CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Reproduction may be subject to royalty payments or a licensing agreement.
Violators may be prosecuted.
©
ii ISO 2006 – All rights reserved

---------------------- Page: 5 ----------------------
ISO/DIS 148-2
Contents Page
1 Scope.1
2 Normative references.1
3 Terms and definitions .2
3.1 Definitions pertaining to the machine.2
3.2 Definitions pertaining to energy .3
3.3 Definitions pertaining to test pieces .3
4 Symbols.4
5 Testing machine .5
6 Direct Verification.5
6.1 Foundation/installation.5
6.2 Machine framework.5
6.3 Pendulum .6
6.4 Anvil and supports.10
6.5 Indicating equipment .11
7 Indirect verification by use of reference test pieces .12
8 Frequency of verification.12
9 Error and repeatability .13
9.1 Repeatability .13
9.2 Error.13
10 Verification report.13
10.1 Direct verification .14
10.2 Indirect verification .14

Figures:
Figure 1 — Parts of a pendulum-type impact test machine.15
Figure 2 — The strikers, test-piece supports and anvils of pendulum-type impact test machines .16
Figure 3 — Configuration of test piece supports and anvils of an industrial, pendulum-type
impact test machine.18
Figure 4 — Determination of the initial potential energy .19

Tables:
Table 1 — Symbols and their meanings .4
Table 2 — Values for repeatability and error.13
Table 3 — Geometrical characteristics .17

© ISO 2005 — All rights reserved iii

DRAFT 2006

---------------------- Page: 6 ----------------------
ISO/DIS 148-2
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.
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
adopted 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
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 148-2 was prepared by Technical Committee ISO/TC 164, Mechanical Testing of Metals, Subcommittee
SC 4, Toughness Testing.
This second edition cancels and replaces the first edition (1998), 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 machines

iv © ISO 2005 — All rights reserved

DRAFT 2006

---------------------- Page: 7 ----------------------
DRAFT INTERNATIONAL STANDARD ISO/DIS 148-2

Metallic materials — Charpy pendulum impact test —
Part 2:
Verification of testing machines
1 Scope
This part of ISO 148 covers the verification of the constructional elements of pendulum-type impact testing
machines. It is applicable to machines with 2 mm or with 8 mm strikers used for pendulum impact tests carried
out, for instance, in accordance with ISO 148-1.
It can analogously be applied to pendulum impact testing machines of other capacities and of different design.
Impact machines used for industrial, general or research laboratory testing of metallic materials in accordance
with this part of ISO 148 are referred to as industrial machines. Those with more stringent requirements are
referred to as reference machines. Specifications for the verification of reference machines are found in
ISO 148-3.
This part of ISO 148 describes two methods of verification.
a) The direct method, which is static in nature and involves measurement of the critical parts of the machine
to ensure that it meets the requirements of this part of ISO 148. Instruments used for the verification and
calibration shall be traceable to national standards. The direct method shall be used when a machine is
being installed or repaired, or if the indirect method gives a non-conforming result.
b) The indirect method, which is dynamic in nature, and which uses reference test pieces to verify points on
the measuring scale.
A pendulum impact testing machine is not in compliance with this part of ISO 148 until it has been verified by
both the direct and indirect methods (see Clause 7).
The requirements for the reference test pieces are found in ISO 148-3.
NOTE This part of ISO 148 takes into account the total energy absorbed in fracturing the test piece using an indirect
method. This total absorbed energy consists of 1) the energy needed to break the test piece itself and 2) the internal
energy losses of the pendulum impact testing machine performing the first half-cycle swing from the initial position.
Internal energy losses are due to:
a) Air resistance, friction of the bearings of the rotation axis and the indicating pointer of the pendulum which can
be determined by the direct method (see 6.3.4).
b) Shock of the foundation, vibration of the frame and pendulum for which no suitable measuring methods and
apparatus have been developed.
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 references, the latest edition of the referenced
document (including any amendments) applies.
ISO 148-1: Metallic materials — Charpy pendulum impact test — Part 1: Test method.
© ISO 2005 — All rights reserved 1

DRAFT 2006

---------------------- Page: 8 ----------------------
ISO/DIS 148-2
ISO 148-3: Metallic materials — Charpy pendulum impact test — Part 3: Preparation and characterization of
Charpy V-notch test pieces for indirect verification of pendulum impact machines.
3 Terms and definitions
For the purposes of this part of ISO 148, the following definitions apply.
3.1 Definitions pertaining to the machine
3.1.1
anvil
the portion of the machine that serves to properly position the test piece for impact with respect to the striker
and the test piece supports, and supports the test piece under the force of the strike
3.1.2
base
that part of the framework of the machine located below the horizontal plane of the supports
3.1.3
centre of percussion
that point in a body at which, on striking a blow, the percussive action is the same as if the whole mass of the
body was concentrated at the point (see Figure 4)
NOTE When a simple pendulum delivers a blow along a horizontal line passing through the centre of percussion,
there is no resulting horizontal reaction at the axis of rotation.
3.1.4
centre of strike
that point on the striking edge of the pendulum at which, in the free hanging position of
the pendulum, the vertical edge of the striker meets the upper horizontal plane of a test piece of half standard
height (i.e. 5 mm) or equivalent gauge bar resting on the test piece supports (see Figure 2)
3.1.5
industrial machine
impact machine used for industrial, general, or most research-laboratory testing of metallic materials
NOTE 1 These machines are not used to establish reference values.
NOTE 2 Industrial machines are verified using the procedures described in this part of ISO 148.
3.1.6
reference machine
pendulum impact testing machines used to determine the reference energy of a reference test piece
3.1.7
striker
the portion of the pendulum that contacts the test piece
NOTE The edge that actually contacts the test piece may have a radius of 2 mm (the 2 mm striker) or a radius of
8 mm (the 8 mm striker). (See Figure 2.)
3.1.8
test piece supports
the portion of the machine that serves to properly position the test piece for impact, with respect to the centre
of percussion of the pendulum, the striker and the anvils. (see Figures 2 and 3)
2 © ISO 2005 — All rights reserved

DRAFT 2006

---------------------- Page: 9 ----------------------
ISO/DIS 148-2
3.2 Definitions pertaining to energy
3.2.1
total absorbed energy (absorbed energy)
K
T
the total energy required to break a test piece when tested by a pendulum impact testing machine
NOTE It is equal to the difference in the potential energy from the starting position of the pendulum to the end of the
first half swing during which the test piece is broken (see Clause 6.3)
3.2.2
initial potential energy (potential energy)
K
P
Difference between the potential energy of the pendulum hammer prior to its release for the impact test, and
the potential energy of the pendulum hammer at the position of impact, as determined by direct verification
(see Clause 6.3.1)
3.2.3
absorbed energy)
K
Energy required to break a test piece with a pendulum impact testing machine, as indicated by the pointer of
other readout device, which is corrected for friction
NOTE 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 striker radius, that is KV for example.
2
3.2.4
nominal initial potential energy (nominal energy)
K
N
the energy assigned by the manufacturer of the pendulum impact testing machine
3.2.5
reference energy
K
R
the average absorbed energy associated with test pieces used to verify the performance of pendulum impact
machines
3.2.6
reference test piece:
Impact test pieces used to verify the suitability of pendulum impact testing machines by comparing the
indicated energy measured by that machine to the reference energy associated with the test pieces
NOTE Reference test pieces are prepared in accordance with ISO 148-3.
3.3 Definitions pertaining to test pieces
(placed in the test position on the supports of the machine) (See Figures 2 and 3)
3.4.1
height
distance between the notched face and the opposite face
3.4.2
width
dimension perpendicular to the height that is parallel to the notch
3.4.3
length
largest dimension at right angles to the notch
© ISO 2005 — All rights reserved 3

DRAFT 2006

---------------------- Page: 10 ----------------------
ISO/DIS 148-2
4 Symbols
For the purposes of this part of ISO 148, the symbols and designations in Table 1 are applicable.
Table 1 — Symbols and their meanings
a
Unit Meaning
Symbol
K J Nominal initial potential energy (nominal energy)
N
K J Initial potential energy (potential energy)
P
K J Energy of a set of Charpy reference test pieces
R
K J Absorbed energy
K J Total absorbed energy
T
J or degree Indicated energy or angle of rise when the machine is operated in the normal manner
K or β
1 1
without a test piece in position
J or degree Indicated energy or angle of rise when the machine is operated in the normal manner
K or β
2 2
without a test piece in position and without resetting the indication mechanism
J or degree Indicated energy or angle of rise after 11 half swings when the machine is operated
K or β
3 3
in the normal manner without a test piece in position and without resetting the
indication mechanism
F Force exerted by the pendulum when measured at a distance of l
N
2
h m Height of fall of pendulum
h m Height of rise of pendulum
1
l
m Distance to centre of test piece (centre of striker) from the axis of rotation (length of
pendulum)
l m Distance to the centre of percussion from the axis of rotation
1
l m Distance to the point of application of the force F from the axis of rotation
2
M N·m The moment equal to the product Fl
2
p J Energy loss caused by pointer friction
p′ J Energy loss caused by bearing friction and air resistance
p
J Correction of energy losses for an angle of swing β
β
t s Period of the pendulum
T s Total time for 100 swings of the pendulum
T s Maximum value of T
max
T Minimum value of T
s
min
W N Weight of the pendulum
α degree Angle of fall of the pendulum
β degree Angle of rise of the pendulum
a
see Figure 4


4 © ISO 2005 — All rights reserved

DRAFT 2006

---------------------- Page: 11 ----------------------
ISO/DIS 148-2
5 Testing machine
A pendulum impact testing machine consists of the following parts (see Figures 1 to 3):
a) foundation/installation;
b) machine framework — the structure supporting the pendulum, excluding the foundation;
c) pendulum including the hammer;
d) anvils and supports (see Figures 2 and 3);
e) indicating equipment for the absorbed energy (e.g. scale and friction pointer or electronic readout device).
6 Direct Verification
Direct verification of the machine can occur only after installation and involves the inspection of the following
items:
a) foundation/installation,
b) machine framework,
c) pendulum, including the hammer and the striker,
d) anvils and supports, and
e) indicating equipment.
6.1 Foundation/installation
The foundation to which the machine is fixed and the method(s) of fixing the machine to the foundation are of
utmost importance.
6.1.1 Inspection of the machine foundation usually cannot be made once the machine has been installed,
thus documentation made at the time of installation shall be produced to provide assurance that the mass of
the foundation is not less than 40 times that of the pendulum.
6.1.2 Inspection of the installed machine shall consist of the following.
a) Ensuring that the bolts are torqued to the value specified by the machine manufacturer. The torque value
shall be noted in the document provided by the manufacturer of the machine (see 6.1.1). If other
mounting arrangements are used or selected by an end user, equivalency shall be demonstrated.
b) Ensuring that the machine is not subject to external vibrations transmitted through the foundation at the
time of the impact test.
NOTE This can be accomplished, for example, by placing a small container of water on any convenient location on
the machine framework. Absence of ripples on the water surface indicates that this requirement is met.
6.2 Machine framework
Inspection of the machine framework (see Figure 1) shall consist of determining the following items:
a) free position of the pendulum;
b) location of the pendulum in relation to the supports;
© ISO 2005 — All rights reserved 5

DRAFT 2006

---------------------- Page: 12 ----------------------
ISO/DIS 148-2
c) transverse and radial play of the pendulum bearings;
d) clearance between the hammer and the framework.
Machines manufactured after the original publication date of this part of ISO 148 shall have a reference plane
from which measurements can be made.
6.2.1 The axis of rotation of the pendulum shall be parallel to the reference plane to within 2/1 000. This
shall be certified by the manufacturer.
6.2.2 The machine shall be installed so that the reference plane is horizontal to within 2/1 000.
For pendulum impact testing machines without a reference plane, the axis of rotation shall be established to
be horizontal to within 4/1 000 directly or a reference plane shall be established from which the horizontality of
the axis of rotation can be verified as described above.
6.2.3 When hanging free, the pendulum shall hang so that the striking edge is within 0,5 mm of the position
where it would just touch the test specimen.
NOTE This condition can be determined using a gauge in the form of a bar, approximately 55 mm in the length and
of rectangular section, 9,5 mm in height and approximately 10 mm in width (see Figure 3). The distance between the
striker and the bar is then measured.
6.2.4 The plane of the swing of the pendulum shall be 90° ± 0,1° (3/1 000) to the axis of rotation.
6.2.5 The striker shall make contact over the full width of the test piece.
NOTE One method of verifying this is as follows. A test piece having dimensions of 55 mm × 10 mm × 10 mm is
tightly wrapped in thin paper (e.g. by means of adhesive tape), and the test piece is placed in the test-piece supports.
Similarly, the striker edge is tightly wrapped in carbon paper with the carbon side outermost (i.e. not facing the striker).
From its position of equilibrium, the pendulum is raised a few degrees, released so that it contacts the test piece, and
prevented from contacting the test piece a second time. The mark made by the carbon paper on the paper covering the
test piece should extend completely across the paper. This test may be performed concurrently with that of checking the
angle of contact between the striker and the test piece (see 6.3.7).
6.2.6 The pendulum shall be located so that the centre of the striker and the centre of the gap between the
anvils are coincident to within 0,5 mm.
6.2.7 Axial play in the pendulum bearings shall not exceed 0,25 mm measured at the striker under a
transverse force of approximately 4 % of the effective weight of the pendulum, W [see Figure 4 b)], applied at
the centre of strike.
6.2.8 Radial play of the shaft in the pendulum bearings shall not exceed 0,08 mm, when a force of
150 N ± 10 N is applied at a distance L at right angles to the plane of swing of the pendulum.
NOTE The radial play can be measured, for example, by a dial gauge mounted on the machine frame at the bearing
housing, in order to indicate movement at the end of the shaft (in the bearings) when a force of about 150 N is applied to
the pendulum perpendicularly to the plane of the swing.
6.2.9 For new machines, it is recommended that the mass of the base of the machine framework should be
at least 12 times that of the pendulum.
NOTE The base of the machine is that portion of the framework located below the plane(s) of the supports.
6.3 Pendulum
The verification of the pendulum (including striker) should consist of determining the following quantities:
a) potential energy, K ,
P
6 © ISO 2005 — All rights reserved

DRAFT 2006

---------------------- Page: 13 ----------------------
ISO/DIS 148-2
b) error in the indicated energy, K
S
c) velocity of the pendulum at instant of impact,
d) energy absorbed by friction,
e) position of centre of percussion (i.e. distance from centre of percussion to axis of rotation),
f) type of striker and
g) the angle of the line of contact of the striker and the horizontal axis of the test piece.
6.3.1 The potential energy, K , shall not differ from the nominal energy, K , by more that ± 1 %. The
P N
potential energy K shall be determined as follows:
P
The moment of the pendulum is determined by supporting the pendulum at a chosen distance, l , from the
2
axis of rotation by means of a knife edge on a balance or dynamometer in such a manner that the line through
the axis
of rotation which joins the centre of gravity of the pendulum is horizontal within 15/1 000 [see Figure 4 a)].
The force, F, and the length, l , shall each be determined to an accuracy of ± 0,2 %. The moment, M, is the
2
product F × l .
2
NOTE 1 Length l can be equal to length l.
2
The angle of fall, α, shall be measured to an accuracy of ± 0,4°; this angle can be greater than 90°.
The potential energy, K , is then calculated by t
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.