SIST EN ISO 293:2023

SLOVENSKI STANDARD
01-maj-2023
Polimerni materiali - Preskušanci plastomerov, oblikovani s stiskanjem (ISO
293:2023)
Plastics - Compression moulding of test specimens of thermoplastic materials (ISO
293:2023)
Kunststoffe - Formgepresste Probekörper aus Thermoplasten (ISO 293:2023)
Plastiques - Moulage par compression des éprouvettes en matières thermoplastiques
(ISO 293:2023)
Ta slovenski standard je istoveten z: EN ISO 293:2023
ICS:
83.080.20 Plastomeri Thermoplastic materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 293
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2023
EUROPÄISCHE NORM
ICS 83.080.20 Supersedes EN ISO 293:2005
English Version
Plastics - Compression moulding of test specimens of
thermoplastic materials (ISO 293:2023)
Plastiques - Moulage par compression des éprouvettes Kunststoffe - Formgepresste Probekörper aus
en matières thermoplastiques (ISO 293:2023) Thermoplasten (ISO 293:2023)
This European Standard was approved by CEN on 24 February 2023.

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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 293:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 293:2023) 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 September 2023, and conflicting national standards
shall be withdrawn at the latest by September 2023.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 293:2005.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
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, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 293:2023 has been approved by CEN as EN ISO 293:2023 without any modification.

INTERNATIONAL ISO
STANDARD 293
Fourth edition
2023-02
Plastics — Compression moulding
of test specimens of thermoplastic
materials
Plastiques — Moulage par compression des éprouvettes en matières
thermoplastiques
Reference number
ISO 293:2023(E)
ISO 293:2023(E)
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, 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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 293:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Apparatus . 2
4.1 Moulding press . 2
4.2 Moulds . 2
4.2.1 General . 2
4.2.2 Fabrication . 3
4.2.3 Types . 3
5 Procedure .4
5.1 Preparation of moulding material. 4
5.1.1 Drying of granular material . 4
5.1.2 Preparation of preforms . 4
5.2 Moulding . 5
5.3 Cooling . 5
5.3.1 General . 5
5.3.2 Cooling methods . 5
6 Inspection of the moulded specimens or sheets . 6
7 Specimen preparation report .6
Bibliography . 7
iii
ISO 293:2023(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 of 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
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 9,
Thermoplastic materials, in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 249, Plastics, in accordance with the Agreement on technical cooperation
between ISO and CEN (Vienna Agreement).
This fourth edition cancels and replaces the third edition (ISO 293:2004), which has been technically
revised.
The main changes are as follows:
— the definition for “cooling rate” has been revised (see 3.6);
— requirements regarding the biggest clamping force and the highest platens temperature have been
changed (see 4.1);
— the description of common specifications of positive mould has been given (see 4.2.3.3);
— the conditions for the use of vacuum oven while material drying have been added (see 5.1.1);
— the methods of cooling rate have been revised (see Table 1);
— a bibliography has been added.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
iv
ISO 293:2023(E)
Introduction
For reproducible test results, specimens with a specified state are required. In contrast to injection
moulding, the aim of compression moulding is to produce test specimens and sheets for machining or
stamping of test specimens that are homogeneous and isotropic.
In the process of compression moulding, mixing of material takes place on a negligible scale. Granules
and powders fuse only at their surfaces and preforms (milled sheets) are only partially softened.
Isotropic and homogeneous specimens can, therefore, only be obtained when the moulding material
is itself homogeneous and isotropic. This has to be considered when processing multiphase materials,
such as ABS, which retain their internal structure.
The cooling rate in the crystallization stage has a great influence on the properties of semi-crystalline
or crystalline polymer (such as PB, PE, PP, etc.), so it is necessary to control the cooling rate more
strictly at the cooling stage.
v
INTERNATIONAL STANDARD ISO 293:2023(E)
Plastics — Compression moulding of test specimens of
thermoplastic materials
1 Scope
This document specifies the general principles and the procedures to be followed with thermoplastics
in the preparation of compression-moulded test specimens, and sheets from which test specimens can
be machined or stamped.
NOTE In order to obtain mouldings in a reproducible state, the main steps of the procedure, inc
...