EN ISO 294-1:2017

• Abstract:

  ISO 294-1:2017 specifies the general principles to be followed when injection moulding test specimens of thermoplastic materials and gives details of mould designs for preparing two types of specimen for use in acquiring reference data, i.e. type A1 and type B1 test specimens as specified in ISO 20753, and provides a basis for establishing reproducible moulding conditions. Its purpose is to provide consistent descriptions of the main parameters of the moulding process and to establish a uniform practice in reporting moulding conditions. The particular conditions required for the reproducible preparation of test specimens will vary for each material used and are given in the International Standard for the relevant material or are to be agreed upon between the interested parties.; NOTE Interlaboratory tests with acrylonitrile/butadiene/styrene (ABS), styrene/butadiene (SB) and poly(methyl methacrylate) (PMMA) have shown that mould design is an important factor in the reproducible preparation of test specimens.

• Status: Published
• Publication Date: 06-Jun-2017
• Withdrawal Date: 30-Dec-2017
• ICS: 83.080.20 - Thermoplastic materials
• Technical Committee: CEN/TC 249 - Plastics
• Drafting Committee: CEN/TC 249 - Plastics
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 07-Jun-2017
• Completion Date: 07-Jun-2017
• Ref Project: SIST EN ISO 294-1:2017 - Plastics - Injection moulding of test specimens of thermoplastic materials - Part 1: General principles, and moulding of multipurpose and bar test specimens (ISO 294-1:2017)

• Replaces: EN ISO 294-1:1998 - Plastics - Injection moulding of test specimens of thermoplastic materials - Part 1: General principles, and moulding of multipurpose and bar test specimens (ISO 294-1:1996)
• Effective Date: 08-Jun-2022
• Replaces: EN ISO 294-1:1998/A1:2002 - Plastics - Injection moulding of test specimens of thermoplastic materials - Part 1: General principles, and moulding of multipurpose and bar test specimens (ISO 294-1:1996/Amd. 1:2001)
• Effective Date: 14-Jun-2017
• Refers: ISO 294-3:2002 - Plastics — Injection moulding of test specimens of thermoplastic materials — Part 3: Small plates
• Effective Date: 25-Aug-2026
• Refers: ISO 20753:2008 - Plastics — Test specimens
• Effective Date: 25-Aug-2026
• Refers: ISO 294-2:1996 - Plastics — Injection moulding of test specimens of thermoplastic materials — Part 2: Small tensile bars
• Effective Date: 25-Aug-2026
• Refers: ISO 294-4:2001 - Plastics — Injection moulding of test specimens of thermoplastic materials — Part 4: Determination of moulding shrinkage
• Effective Date: 25-Aug-2026
• Refers: ISO 179-1:2010 - Plastics — Determination of Charpy impact properties — Part 1: Non-instrumented impact test
• Effective Date: 09-Feb-2026
• Refers: EN 12967-1:2007 - Health informatics - Service architecture - Part 1: Enterprise viewpoint
• Effective Date: 28-Jan-2026
• Refers: CEN/TR 16045:2010 - Construction Products - Assessment of release of dangerous substances - Content of regulated dangerous substances - Selection of analytical methods
• Effective Date: 28-Jan-2026
• Referred By: EN 60695-2-13:2010 - Fire hazard testing - Part 2-13: Glowing/hot-wire based test methods - Glow-wire ignition temperature (GWIT) test method for materials
• Effective Date: 09-Feb-2026
• Referred By: EN IEC 63522-56:2025 - Electrical relays - Tests and measurements - Part 56: Ball Pressure test
• Effective Date: 09-Feb-2026
• Referred By: EN 60695-11-10:2013 - Fire hazard testing - Part 11-10: Test flames - 50 W horizontal and vertical flame test methods
• Effective Date: 09-Feb-2026
• Referred By: EN IEC 60695-2-13:2021 - Fire hazard testing - Part 2-13: Glowing/hot-wire based test methods - Glow-wire ignition temperature (GWIT) test method for materials
• Effective Date: 09-Feb-2026
• Referred By: EN 60695-10-2:2014 - Fire hazard testing - Part 10-2: Abnormal heat - Ball pressure test method
• Effective Date: 09-Feb-2026
• Referred By: EN IEC 60695-2-12:2021 - Fire hazard testing - Part 2-12: Glowing/hot-wire based test methods - Glow-wire flammability index (GWFI) test method for materials
• Effective Date: 09-Feb-2026

Overview

EN ISO 294-1:2017 - Plastics: Injection moulding of test specimens of thermoplastic materials - Part 1: General principles, and moulding of multipurpose and bar test specimens (ISO 294-1:2017) is a CEN-endorsed standard that defines the general principles and mould designs for preparing reproducible injection-moulded test specimens. It specifies mould designs for type A1 and type B1 specimens (as per ISO 20753) and establishes a consistent framework for recording and reporting moulding conditions to obtain comparable reference data across laboratories and manufacturers.

Key Topics

• Mould design and types: Guidance for ISO multi‑cavity and single‑cavity moulds and interchangeable cavity plates to support reproducible specimen production.
• Main process parameters: Definitions and conventions for mould temperature, melt temperature, melt pressure, hold pressure, moulding cycle and cycle time-ensuring consistent terminology when reporting results.
• Equipment and apparatus: Requirements for injection‑moulding machines, recommended measurement points (thermometers, melt temperature measurement), screw and clamping considerations, and moulding volume.
• Procedure and conditioning: Principles for conditioning feedstock, injection‑moulding steps, measurement of temperatures/pressures, and post‑moulding treatment of specimens.
• Annexes for practical setup: Informative annexes provide runner configurations, standardized mould components, an example mould layout, methods for setting machine parameters (Annex D) and methods to determine hold pressure and hold time (Annex E).
• Reproducibility emphasis: Notes from interlaboratory tests (e.g., ABS, SB, PMMA) underline that mould design and controlled parameters are critical for reproducible test specimens.

Applications

• Quality control and materials testing labs producing reference specimens for mechanical, thermal or impact testing.
• Polymer manufacturers and compounders validating batch properties under standardized moulding conditions.
• Injection‑moulding equipment manufacturers and toolmakers designing test‑specimen moulds compliant with ISO 294‑1.
• R&D and interlaboratory studies where consistent specimen preparation is essential for comparable data.
  Using EN ISO 294‑1:2017 helps minimize variability caused by processing and mould-related factors, improving the reliability of property data for thermoplastic materials.

Related Standards

• ISO 20753 - Test specimens (refers to specimen types A1 and B1)
• ISO 294 series (Parts 2–4) - Additional specimen geometries and shrinkage determination
• ISO 179‑1 - Charpy impact property testing (referenced for specimen preparation)

Adopting EN ISO 294‑1:2017 ensures standardized terminology, repeatable injection‑moulding practices, and clearer reporting-essential for comparable thermoplastic materials testing and certification.

SLOVENSKI STANDARD
01-september-2017
1DGRPHãþD
SIST EN ISO 294-1:2000
SIST EN ISO 294-1:2000/A1:2002
3ROLPHUQLPDWHULDOL9EUL]JDYDQMHSODVWRPHUQLKSUHVNXãDQFHYGHO6SORãQD
QDþHODLQREOLNRYDQMHYHþQDPHQVNLKLQSDOLþDVWLKSUHVNXãDQFHY,62
Plastics - Injection moulding of test specimens of thermoplastic materials - Part 1:
General principles, and moulding of multipurpose and bar test specimens (ISO 294-
1:2017)
Kunststoffe - Spritzgießen von Probekörpern aus Thermoplasten - Teil 1: Allgemeine
Grundlagen und Herstellung von Vielzweckprobekörpern und Stäben (ISO 294-1:2017)
Plastiques - Moulage par injection des éprouvettes de matériaux thermoplastiques -
Partie 1: Principes généraux, et moulage des éprouvettes à usages multiples et des
barreaux (ISO 294-1:2017)
Ta slovenski standard je istoveten z: EN ISO 294-1:2017
ICS:
83.080.20 Plastomeri Thermoplastic materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 294-1
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2017
EUROPÄISCHE NORM
ICS 83.080.20 Supersedes EN ISO 294-1:1998
English Version
Plastics - Injection moulding of test specimens of
thermoplastic materials - Part 1: General principles, and
moulding of multipurpose and bar test specimens (ISO
294-1:2017)
Plastiques - Moulage par injection des éprouvettes de Kunststoffe - Spritzgießen von Probekörpern aus
matériaux thermoplastiques - Partie 1: Principes Thermoplasten - Teil 1: Allgemeine Grundlagen und
généraux, et moulage des éprouvettes à usages Herstellung von Vielzweckprobekörpern und Stäben
multiples et des barreaux (ISO 294-1:2017) (ISO 294-1:2017)
This European Standard was approved by CEN on 13 April 2017.

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, Serbia, 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
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 294-1:2017 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 294-1:2017) has been prepared by Technical Committee ISO/TC 61 "Plastics" in
collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN.
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 December 2017, and conflicting national standards
shall be withdrawn at the latest by December 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 294-1:1998.
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, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 294-1:2017 has been approved by CEN as EN ISO 294-1:2017 without any modification.

INTERNATIONAL ISO
STANDARD 294-1
Second edition
2017-05
Plastics — Injection moulding of
test specimens of thermoplastic
materials —
Part 1:
General principles, and moulding of
multipurpose and bar test specimens
Plastiques — Moulage par injection des éprouvettes de matériaux
thermoplastiques —
Partie 1: Principes généraux, et moulage des éprouvettes à usages
multiples et des barreaux
Reference number
ISO 294-1:2017(E)
©
ISO 2017
ISO 294-1:2017(E)
© ISO 2017, 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. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2017 – All rights reserved

ISO 294-1:2017(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Apparatus . 6
4.1 Moulds . 6
4.1.1 ISO (multi-cavity) moulds . 6
4.1.2 Single-cavity moulds. 9
4.2 Injection-moulding machine .10
4.2.1 General.10
4.2.2 Moulding volume .10
4.2.3 Control system .10
4.2.4 Screw .10
4.2.5 Clamping force .11
4.2.6 Thermometers .11
5 Procedure.11
5.1 Conditioning of material .11
5.2 Injection moulding .12
5.3 Measurement of mould temperature.13
5.4 Measurement of the melt temperature .13
5.5 Post-moulding treatment of test specimens.13
6 Report on test-specimen preparation .13
Annex A (informative) Examples of runner configurations .15
Annex B (informative) Standardized injection-moulding mould components .16
Annex C (informative) Example of an injection mould .17
Annex D (informative) Methods for setting the injection moulding parameters .18
Annex E (informative) Methods of determining the hold pressure and hold time .23
Bibliography .29
ISO 294-1:2017(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 voluntary nature of standards, 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: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 9,
Thermoplastic materials.
This second edition cancels and replaces the first edition (ISO 294-1:1996), which has been technically
revised with the following changes:
— the types of test specimen have been replaced according to ISO 20753;
— Annex D has been added to clarify the methods for setting the operation parameters on injection
machine;
— the original Annex D has been renamed as Annex E.
It also incorporates the Amendments ISO 294-1:1996/Amd.1:2001 and ISO 294-1:1996/Amd.2:2005.
A list of all the parts in the ISO 294 series can be found on the ISO website.
iv © ISO 2017 – All rights reserved

ISO 294-1:2017(E)
Introduction
Many factors in the injection-moulding process influence the properties of moulded test specimens and
hence the measured values obtained when the specimens are used in a test method. The mechanical
properties of such specimens are strongly dependent on the conditions of the moulding process used
to prepare the specimens. Exact definition of each of the main parameters of the moulding process is a
basic requirement for reproducible and comparable operating conditions.
It is important in defining moulding conditions to consider any influence the conditions may have
on the properties to be determined. Thermoplastics exhibit differences in molecular orientation in
crystallization morphology (for crystalline and semicrystalline polymers), in phase morphology (for
heterogeneous thermoplastics) as well as in the orientation of anisotropic fillers such as short fibres.
Residual (“frozen-in”) stresses in the moulded test specimens and thermal degradation of the polymer
during moulding also influence properties. Each of these phenomena must be controlled to minimize
variability of the numerical values of the properties measured.
Care has been taken to ensure that the ISO moulds described can all be fitted in existing injection-
moulding equipment and have interchangeable cavity plates.
INTERNATIONAL STANDARD ISO 294-1:2017(E)
Plastics — Injection moulding of test specimens of
thermoplastic materials —
Part 1:
General principles, and moulding of multipurpose and bar
test specimens
1 Scope
This document specifies the general principles to be followed when injection moulding test specimens
of thermoplastic materials and gives details of mould designs for preparing two types of specimen for
use in acquiring reference data, i.e. type A1 and type B1 test specimens as specified in ISO 20753, and
provides a basis for establishing reproducible moulding conditions. Its purpose is to provide consistent
descriptions of the main parameters of the moulding process and to establish a uniform practice in
reporting moulding conditions. The particular conditions required for the reproducible preparation of
test specimens will vary for each material used and are given in the International Standard for the
relevant material or are to be agreed upon between the interested parties.
NOTE Interlaboratory tests with acrylonitrile/butadiene/styrene (ABS), styrene/butadiene (SB) and
poly(methyl methacrylate) (PMMA) have shown that mould design is an important factor in the reproducible
preparation of test specimens.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 179-1, Plastics — Determination of Charpy impact properties — Part 1: Non-instrumented impact test
ISO 294-2, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 2: Small
tensile bars
ISO 294-3:2002, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 3:
Small plates
ISO 294-4, Plastics — Injection moulding of test specimens of thermoplastic materials — Part 4:
Determination of moulding shrinkage
ISO 20753, Plastics — Test specimens
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
ISO 294-1:2017(E)
3.1
mould temperature
T
C
average temperature of the mould cavity surfaces measured after the system has attained thermal
equilibrium and immediately after opening the mould
Note 1 to entry: It is expressed in degrees Celsius (°C).
3.2
melt temperature
T
M
temperature of the molten plastic in a free shot
Note 1 to entry: It is expressed in degrees Celsius (°C).
3.3
melt pressure
p
pressure of the plastic material in front of the screw at any time during the moulding process
Note 1 to entry: It is expressed in megapascals (MPa).
3.4
hold pressure
p
H
melt pressure (3.3) during the hold time (3.9)
Note 1 to entry: It is expressed in megapascals (MPa).
3.5
moulding cycle
complete sequence of operations in the moulding process required for the production of one set of test
specimens
Note 1 to entry: See Figure 1.
3.6
cycle time
t
T
time required to carry out a complete moulding cycle (3.5)
Note 1 to entry: The cycle time is the sum of the injection time, t , the cooling time, t and the mould-open time, t .
I C, O
Note 2 to entry: It is expressed in seconds (s).
2 © ISO 2017 – All rights reserved

ISO 294-1:2017(E)
Key
X time, t
Y melt pressure, p, and longitudinal screw position, l
1 cycle time, t
T
2 injection time, t
I
3 hold time, t
H
4 cooling time, t
C
5 mould-open time, t
O
6 melt pressure, p
7 longitudinal position of screw, l
8 mould opening
9 mould closing
NOTE The melt pressure during the cooling phase is not zero due to back pressure effects.
Figure 1 — Schematic diagram of an injection-moulding cycle showing the melt pressure (full
line) and the longitudinal position of the screw (dashed line) as a function of time
3.7
injection time
t
I
time from the instant the screw starts to move forward until the switchover point between the injection
period and the hold period
Note 1 to entry: It is expressed in seconds (s).
ISO 294-1:2017(E)
3.8
cooling time
t
C
time from the end of the injection period until the mould starts to open
Note 1 to entry: It is expressed in seconds (s).
3.9
hold time
t
H
time during which the pressure is maintained at the hold pressure (3.4)
Note 1 to entry: It is expressed in seconds (s).
3.10
mould-open time
t
O
time from the instant the mould starts to open until the mould is closed and exerts the full clamping
force (3.19)
Note 1 to entry: It is expressed in seconds (s).
Note 2 to entry: It includes the time required to remove the mouldings from the mould.
3.11
cavity
part of the hollow space in a mould that produces one specimen
3.12
single-cavity mould
mould with one cavity (3.11) only
3.13
multi-cavity mould
mould that has two or more identical cavities (3.11) in a parallel-flow arrangement
Note 1 to entry: Identical flow-path geometries and symmetrical positioning of the cavities in the mould ensure
that all test specimens from one shot are equivalent in their properties.
3.14
family mould
multi-cavity mould (3.13) containing cavities (3.11) which have different geometries
3.15
ISO mould
one of several standard moulds (designated ISO 20753 type A1, B1, C1, D11 and D12) intended for the
reproducible preparation of test specimens with comparable properties
Note 1 to entry: The moulds have a fixed plate with a central sprue, plus a multi-cavity cavity plate as described
in 3.13.
Note 2 to entry: Additional details are given in 4.1.1.4. An example of a complete mould is shown in Annex C.
3.16
critical cross-sectional area
A
c
cross-sectional area of the cavity (3.11) in a single-cavity mould (3.12) or multi-cavity mould (3.13) at the
position where the critical portion of the test specimen, i.e. that part on which the measurement will be
made, is moulded
Note 1 to entry: It is expressed in square millimetres (mm ).
4 © ISO 2017 – All rights reserved

ISO 294-1:2017(E)
Note 2 to entry: For tensile test specimens, for instance, the critical portion of the test specimen is the narrow
section which is subjected to the greatest stress during testing.
3.17
moulding volume
V
M
ratio of the mass of the moulding to the density of the solid plastic
Note 1 to entry: It is expressed in cubic millimetres (mm ).
3.18
projected area
A
p
overall profile of the moulding projected on to the parting plane
Note 1 to entry: It is expressed in square millimetres (mm ).
3.19
clamping force
F
M
force holding the plates of the mould closed
Note 1 to entry: It is expressed in kilonewtons (kN).
3.20
injection velocity
v
I
average velocity of the melt as it passes through the critical cross-sectional area (3.16)
Note 1 to entry: It is expressed in millimetres per second (mm/s).
3.21
shot volume Max.
V
S
product of the maximum metering stroke of the injection-moulding machine and the cross-sectional
area of the screw
Note 1 to entry: It is expressed in cubic millimetres (mm ).
3.22
mass of moulding
total mass of the test specimens, the runner(s) and the sprue in a single moulding
Note 1 to entry: It is expressed in grams (g).
3.23
mass of test specimen
mass of a single specimen, excluding the runner(s) and the sprue
Note 1 to entry: It is expressed in grams (g).
ISO 294-1:2017(E)
3.24
sink mark ratio
SR
indication of the relative depth of a sink mark on the surface of the specimen, as given by:
hh−
()
maxmin
SR =
h
max
where
h is the minimum thickness of the specimen, calculated as the average of the thicknesses at
min
three points P , P and P along the length of the specimen, as defined in
min1 min2 min3
Figures E.2 and E.3;
h is the maximum thickness of the specimen, calculated as the average of the thicknesses at
max
three points P , P and P along the length of the specimen, as defined in
max1 max2 max3
Figures E.2 and E.3.
Note 1 to entry: It is expressed to two significant figures (e.g. 0,032).
3.25
cavity pressure
pressure of the melt in the mould cavity, measured with a pressure sensor on the inner surface of
the cavity
Note 1 to entry: It is expressed in megapascals (MPa).
4 Apparatus
4.1 Moulds
4.1.1 ISO (multi-cavity) moulds
4.1.1.1 ISO moulds are strongly recommended for producing test specimens for the acquisition of data
which are intended to be comparable (see ISO 10350-1, ISO 10350-2, ISO 11403-1, ISO 11403-2 and
ISO 11403-3), as well as for use in the case of disputes involving International Standards.
4.1.1.2 Multipurpose test specimen as specified in ISO 20753 type A1 shall be moulded in a two-cavity
mould using a Z- or T-runner (see Annex A). The mould as shown in Figure 2 shall meet the requirements
specified in 4.1.1.4. Of the two types of runner, the Z-runner is preferred owing to the more symmetrical
closure force obtained. The specimen mouldings produced shall have the dimensions of the ISO 20753
type A1 specimen specified in ISO 20753.
4.1.1.3 Rectangular 80 mm × 10 mm × 4 mm bars (ISO 20753 type B1) shall be moulded in a four-cavity
mould with a double-T runner. The mould shall be as shown in Figure 3 and shall meet the requirements
specified in 4.1.1.4. The bars produced shall have the same cross-sectional dimensions along their central
section as multipurpose test specimens (see ISO 20753) and a length of 80 mm ± 2 mm.
4.1.1.4 The main constructional details of ISO 20753 type A1 and B1 moulds are shown in Figures 2
and 3. They shall meet the following requirements:
a) The sprue diameter on the nozzle side shall be at least 4 mm.
b) The width and height (or the diameter) of the runner system shall be at least 5 mm.
c) The cavities shall be one-end gated as shown in Figures 2 and 3.
6 © ISO 2017 – All rights reserved

ISO 294-1:2017(E)
d) The height of the gate shall be at least two-thirds the height of the cavity and the width of the gate
shall be equal to that of the cavity at the point where the gate enters the cavity.
e) The gate shall be as short as possible, in any case not exceeding 3 mm.
Dimensions in millimetres
Key
Sp sprue
G gates
3 2
NOTE Moulding volume V ≈ 30 000 mm , projected area A ≈ 6 300 mm .
M p
Figure 2 — Two-cavity mould for an ISO 20753 type A1 mould
Dimensions in millimetres
Key
Sp sprue
G gates
3 2
NOTE Moulding volume V ≈ 30 000 mm , projected area A ≈ 6 500 mm .
M p
Figure 3 — Four cavity mould for an ISO 20753 type B1 mould
ISO 294-1:2017(E)
f) The draft angle of the runners shall be at least 10°, but not more than 30°. The cavity shall have a
draft angle not greater than 1°, except in the area of tensile-specimen shoulders where the draft
angle shall not be greater than 2°.
g) The dimensions of the cavities shall be such that the dimensions of the test specimens produced
conform to the requirements given in the relevant test standard. To allow for different degrees of
moulding shrinkage, the dimensions of the cavities shall be chosen so that they are between the
nominal value and the upper limit of the dimensions specified for the specimen concerned. In the
case of ISO 20753 type A1 and B1 moulds, the main cavity dimensions, in millimetres, shall be as
follows (see ISO 20753):
1) depth: 4,0 mm to 4,2 mm;
2) width of central section: 10,0 mm to 10,2 mm;
3) length (ISO 20753 type B1 mould): 80 mm to 82 mm.
h) Ejector pins, if used, shall be located outside the test area of the specimen, i.e. at the shoulders
of dumbbell specimens produced from ISO 20753 type A1 and type C moulds (for type C, see
ISO 294-2), outside the central 20 mm section of bar specimens from ISO 20753 type B1 moulds
and outside the 50-mm-diameter central area of plate specimens from ISO 20753 type D moulds
(see ISO 294-3).
i) The heating/cooling system for the mould plates shall be designed so that, under operating
conditions, the difference in temperature between any point on the surface of a cavity and either
plate is less than 5 °C.
j) Interchangeable cavity plates and gate inserts are recommended to permit rapid changes in
production from one type of test specimen to another. Such changes are facilitated by using shot
capacities, V , which are as similar as possible. An example is shown in Annex A.
s
k) It is recommended that a pressure sensor be fitted in the central runner to give proper control
of the injection period (the sensor is mandatory for ISO 294-4). A sensor position suitable for the
various types of ISO mould is given in ISO 294-3:2002, Figure 2 and 4.1 k).
l) To ensure that cavity plates are interchangeable between different ISO moulds, it is important to
note the following constructional details in addition to those shown in Figures 2 and 3 and those
given in ISO 294-2 and ISO 294-3:
1) It is recommended that a cavity length of 170 mm be used for multipurpose test specimens
moulded in the ISO 20753 type A1 mould. This gives a maximum length of 180 mm for the
space between the cavity plates.
2) The width of the mould plates may be affected by the minimum distance required between the
connection points for the heating/cooling channels. In addition, space may need to be provided
in ISO 20753 type B1 moulds for the fitting of a special insert enabling notched bars for use in
ISO 179-1 to be moulded.
3) Lines along which the test specimens can be cut from the runners may be defined, e.g. 170 mm
apart for ISO 20753 type A1, B1 and C moulds (for type C, see ISO 294-2). A second pair of lines
80 mm apart may be defined for cutting bars from multipurpose test specimens from a type A
mould and may be used as well for cutting off small-plate mouldings (see ISO 294-3).
m) To make it easier to check that all the specimens from a mould are identical, it is recommended that
the individual cavities be marked, but outside the test area of the specimen [see item h) above].
This can be done very simply by engraving suitable symbols on the heads of the ejector pins, thus
avoiding any damage to the surface of the cavity plate.
n) Surface imperfections can influence the results, especially those of mechanical tests. Where
appropriate, the surfaces of the mould cavities shall be highly polished therefore, the direction of
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ISO 294-1:2017(E)
polishing corresponding to the direction in which the test specimen will be placed under load when
it is tested.
4.1.1.5 For more information on those mould components described in other International Standards,
see Annex B.
4.1.2 Single-cavity moulds
The cavity of a single-cavity mould (see Figure 4) may be that of a dumbbell, a disc or any other shape.
Test specimens from a single-cavity mould generally give values for certain properties which are
different from those obtained with specimens from ISO moulds.
NOTE This difference can occur because the ratio of the volume of the cavity to the volume of the moulding,
V , can be different from that for ISO moulds. Also, the smaller volume of the moulding produced by a single-
M
cavity mould makes conformance with the volume-ratio requirements of 4.2.2 different and failure to conform to
these requirements can contribute to erratic values of properties.
a) Sprue (Sp) normal to moulding plate
b) Sprue parallel to the parting plane (the bend in the runner prevents jetting)
Figure 4 — Examples of single-cavity moulds
4.1.3 Family moulds
A family mould (see Figure 5) may be used to produce, for example, flat bars plus dumbbells and discs.
A family mould may be used when the properties of the test specimens obtained correspond to those
obtained from ISO moulds.
NOTE In most cases, steady, simultaneous filling of the different cavities is not possible with a family mould
under more than one set of moulding conditions. Thus this type of mould is not suitable for the preparation of
referee test specimens. In addition, the injection velocity, v , cannot be defined precisely for a family mould.
I
ISO 294-1:2017(E)
Figure 5 — Example of a family mould
4.2 Injection-moulding machine
4.2.1 General
For further information, see Reference [7].
For the reproducible preparation of test specimens capable of giving comparable results, only
reciprocating-screw injection-moulding machines equipped with all the necessary devices for the
control of the moulding conditions shall be used.
4.2.2 Moulding volume
The ratio of the moulding volume, V , to the shot volume Max., V , shall be between 20 % and 80 % unless
M s
a higher ratio is required by the relevant material standard or is recommended by the manufacturer.
4.2.3 Control system
The control system of the machine shall be capable of maintaining the operating conditions within the
following tolerance limits:
Injection time, t ±0,1 s
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Hold pressure, p ±5 %
H
Hold time, t ±5 %
H
Melt temperature, T ±3 °C
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Mould temperature, T ±3 °C up to 80 °C
C
±5 °C above 80 °C
Mass of moulding ±2 %
4.2.4 Screw
The screw shall be of a type suitable for the moulding material (e.g. length, diameter, thread height,
compression ratio).
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ISO 294-1:2017(E)
It is recommended that a screw with a diameter in the range between 18 mm and 40 mm is used.
4.2.5 Clamping force
The clamping force, F , shall be high enough to prevent flash forming under any operating conditions.
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The minimum clamping force necessary may be calculated from Formula (1):
−3
FA≥×p ×10 (1)
Mp max
where
F is the clamping force, in kilonewtons;
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A is the projected area, in square millimetres;
p
p is the maximum value of the melt pressure, p, in megapascals.
max
The melt pressure, p, which is generated hydraulically for instance, can be calculated from the force, F ,
s
acting longitudinally on the screw using Formula (2):
41× 0 F
s
p = (2)
πD
where
p is the melt pressure, in megapascals;
F is the longitudinal force, in kilonewtons, acting upon the screw;
s
D is the screw diameter, in millimetres.
The recommended minimum clamping force, F , for type ISO 20753 type A1 and B1 moulds is given by
M
-3
F ≥ 6 500 × p × 10 , i.e. 520 kN for a maximum melt pressure of 80 MPa.
M max
An injection-moulding system with interchangeable cavity plates will need to take into account the
ISO 20753 type D11 and D12 moulds for which A ≈ 11 000 mm , thus requiring a significantly higher
p
clamping force.
4.2.6 Thermometers
A needle-probe thermometer accurate to ±1 °C shall be used to measure the melt temperature, T . A
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surface thermometer accurate to ±1 °C shall be used to measure the temperature of the surface of the
mould cavity, which gives the mould temperature, T .
C
5 Procedure
5.1 Conditioning of material
Prior to moulding, condition the pellets or granules of the thermoplastic material as required in the
relevant material standard or as recommended by the manufacturer if no standard covers this subject.
Avoid exposing the material to an atmosphere at a temperature significantly below the temperature of
the workshop to avoid condensation of moisture on to the material.
ISO 294-1:2017(E)
5.2 Injection moulding
5.2.1 Set the machine to the conditions specified in the relevant material standard or agreed between
the interested parties if no standard covers this subject.
5.2.2 For many thermoplastics, the most suitable range for the injection velocity, v, is
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200 mm/s ± 100 mm/s when using ISO 20753 type A1 or B1 moulds. Note that for a given value of the
injection velocity, v , the injection time, t , is inversely proportional to the number of cavities, n, in the
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mould [see Formula (3)]. Keep any changes in the injection velocity during the injection period as small
as possible.
NOTE Methods for setting the injection moulding operation parameters are given in Annex D.
It is applicable to single- and multi-cavity moulds only, and may be calculated from Formula (3):
V
M
v = (3)
I
tA××n
Ic
where
v is the injection velocity, in millimetres per second;
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n is the number of cavities;
A is the critical cross-sectional area, in square millimetres;
c
V is the moulding volume, in cubic millimetres;
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t is the injection time, in seconds.
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5.2.3 The hold pressure, p , is determined by the material’s structure and property; it should be
H
confirmed by relevant properties of specimen with different hold pressure. When similar properties
of the specimen which are free from sink marks, voids, flash and other visible faults at different hold
pressure are acquired, the low pressure is recommended.
The hold pressure may be determined using one of the following methods:
a) using the mass of specimens cut from the moulding;
b) using the sink mark ratio;
c) using the maximum melt pressure that does not yield flash marks.
NOTE Each of these methods is described in Annex E to determine the range of hold pressure, for example,
method c) is for the maximum. Other comparable methods of determining the correct hold pressure are also
allowed.
5.2.4 Ensure that the hold pressure is maintained constant until the material in the gate region has
solidified, i.e. during the hold time, t . The hold time can be determined using one of the following
H
methods:
a) using the mass of the specimens;
b) using the cavity pressure.
NOTE Each of these methods is described in E.2. Other comparable methods of determining the correct hold
time are also allowed.
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ISO 294-1:2017(E)
5.2.5 Discard the mouldings until the machine has reached steady-state operation. Then record the
operating conditions and begin test-specimen collection.
During the moulding process, maintain the steady-state conditions by suitable means, e.g. by checking
the mass of the moulding.
5.2.6 In the event of any change in material, empty the machine and clean it thoroughly. Discard at
least 10 mouldings made using the new material before beginning test-specimen collection again.
5.3 Measurement of mould temperature
Determine the mould temperature, T , after the system has attained thermal equilibrium and
C
immediately after opening the mould. Measure the temperature of the mould-cavity surface at four
points on each pair of the mould cavity using a surface thermometer. Between each reading, cycle the
mould for a minimum of three cycles before continuing with the next point of measurements. Record
each measurement and calculate the mould temperature as the average of all the measurements.
5.4 Measurement of the melt temperature
Measure the melt temperature, T , by one of the following methods.
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a) After thermal equilibrium has been attained, inject a free shot of at least 30 cm into an insulated,
non-metallic container of a suitable size and immediately insert the probe of a preheated rapid-
response needle thermometer into the centre of the molten mass, moving it about gently until the
reading of the thermometer has reached a maximum. Ensure that the preheating temperature is
close to the melt temperature. Use the same injection conditions for the free shot as those to be
used to mould the specimens, allowing the appropriate cycle time to elapse between each free shot.
b) The melt temperature may alternatively be measured by means of a suitable temperature sensor,
provided the result obtained can be shown to be the same as that obtained using the free-shot
method. The sensor shall cause only low heat losses and shall respond rapidly to melt-temperature
changes. Mount the sensor in a suitable place, such as in the nozzle of the injection-moulding
machine. In case of doubt, use the method described in a).
5.5 Post-moulding treatment of test specimens
Once removed from the mould, allow the test specimens to cool gradually and at the same rate to room
temperature in order to avoid any differences in the history of individual test specimens. Protect test
specimens made from thermoplastics sensitive to atmospheric exposure by keeping them in airtight
containers, together with a desiccant if necessary. Perform any additional conditioning as specified in
the relevant material or product standard.
6 Report on test-specimen preparation
The report shall include the following information:
a) a reference to this document, i.e. ISO 294-1;
b) the date, time and place the specimens were moulded;
c) a full description of the material used (type, designation, manufacturer, lot number);
d) details of any conditioning of the material carried out prior to moulding;
e) the type of mould used (type A1, type B1 or, in the case of another type of mould, the type of
specimen produced, the relevant standard, the number of cavities and the gate size and location);
f) details of the injection-moulding machine used (manufacturer, shot volume Max., clamping force,
control systems);
ISO 294-1:2017(E)
g) the moulding conditions;
1) melt temperature, T , in degrees Celsius;
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2) mould temperature, T , in degrees Celsius;
C
3) injection velocity, v , in millimetres per second;
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4) injection time, t , in seconds;
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5) hold pressure, p , in megapascals;
H
6) hold time, t , in seconds;
H
7) cooling time, t , in seconds;
C
8) cycle time, t , in seconds;
T
9) mass of the moulding, in grams;
h) any other relevant details (e.g. the number of mouldings initially discarded, the number retained,
any post-moulding treatment).
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ISO 294-1:2017(E)
Annex A
(informative)
Examples of runner configurations
The layout of a mould may be changed by means of gate inserts as shown in Figure A.1.
a) Injection mould with b) Variant with T-runner c) Variant with double-T runner
Z-runner (e.g. for studying weld
strength)
Key
1 interchangeable gate insert
2 interchangeable cavity plate
Figure A.1 — Different types of runner configuration
ISO 294-1:2017(E)
Annex B
(informative)
Standardized injection-moulding mould components
ISO 6751, Tools for moulding — Ejector pins with cylindrical head
ISO 6753-2, Tools for pressing and moulding — Machined plates — Part 2: Machined plates for moulds
ISO 8017, Tools for moulding — Guide pillars, straight and shouldered, and locating guide pillars, shouldered
ISO 8018, Tools for moulding — Guide bushes, headed, and locating guide bushes, headed
ISO 8404, Tools for moulding — Angle pins
ISO 8405, Tools for moulding — Ejector sleeves with cylindrical head — Basic series for general purposes
ISO 8406, Tools for moulding — Mould bases — Round locating elements and spacers
ISO 8693, Tools for moulding — Flat ejector pins
ISO 8694, Tools for moulding — Shouldered ejector pins
ISO 9449, Tools for moulding — Centring sleeves
ISO 10072, Tools for moulding — Sprue bushes — Dimensions
ISO 10073, Tools for moulding —Support pillars
ISO 10907-1, Tools for moulding — Locating rings — Part 1: Locating rings for mounting without thermal
insulating sheets in sm
...