Mold-Making Handbook

Günter Mennig
K. Stoeckhert
Mold-Making
Handbook
3rd Edition
Mennig, Stoeckhert
Mold-Making Handbook
Günter Mennig
Klaus Stoeckhert
Mold-Making
Handbook
3rd Edition
Hanser Publishers, Munich
Hanser Publications, Cincinnati
The Editors:
Prof. Dr.-Ing. Günter Mennig,
Technische Universität Chemnitz, Institut für Allg. Maschinenbau und Kunststofftechnik, Chemnitz, Germany
Dr.-Ing. Klaus Stoeckhert (†)
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While the advice and information in this book are believed to be true and accurate at the date of going to
press, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors
or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the
material contained herein.
Library of Congress Cataloging-in-Publication Data
Werkzeuge der Kunststoffverarbeitung. English.
Mold-making handbook / [edited by] G?nter Mennig, Klaus Stoeckhert. -- 3rd Edition.
pages cm
ISBN 978-1-56990-446-6 (hardcover)
1. Plastics--Molds. I. Mennig, G?nter. II. Stoeckhert, Klaus, 1913- III. Title.
TP1150.W4613 2012
668.4’12--dc23
2012027079
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detaillierte bibliografische Daten sind im Internet über <http://dnb.d-nb.de> abrufbar.
ISBN 978-1-56990-446-6
E-Book-ISBN 978-1-56990-550-0
All rights reserved. No part of this book may be reproduced or transmitted in any form or by any means,
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without permission in writing from the publisher.
© Carl Hanser Verlag, Munich 2013
Production Management: Steffen Jörg
Coverconcept: Marc Müller-Bremer, www.rebranding.de, München
Coverdesign: Stephan Rönigk
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Printed and bound by Kösel, Krugzell
Printed in Germany
About the Book
The book uses European steel grades.
References for the comparison of US and European steel grades are available, for
example, from Beuth Verlag (Marks, P., US Steels: A comparison of US and European steel grades, German-English (2012), Beuth Verlag, Berlin, www.beuth.de) or
at www.key-to-steel.com.
Contributors
Dipl.-Ing. (FH) Christopherus Bader (Chapter 5.2)
PRIAMUS SYSTEM TECHNOLOGIES AG, Schaffhausen, Switzerland
Prof. Dr.-Ing. Thomas Bauernhansl (Chapter 1.9)
Fraunhofer-Institut für Produktionstechnik und Automatisierung IPA, Stuttgart,
Germany
Dr.-Ing. Joachim Berthold (Chapter 1.2)
Gummersbach, Germany
André Brandt (Chapter 2.2)
HASCO Hasenclever GmbH & Co. KG, Lüdenscheid, Germany
Dipl.-Ing. Otto Eiselen (Chapter 1.4)
HECO Maschinen- und Werkzeugbau GmbH, Lohmar, Germany
Alfred Erstling (Chapter 3.2)
Wuppertal, Germany
Dipl.-Ing. Thomas Eulenstein (Chapter 2.5 and 5.3)
Kunststoff-Institut Lüdenscheid, K.I.M.W. NRW GmbH, Lüdenscheid, Germany
Prof. Dr. Ing. Andreas Gebhardt (Chapter 4.7)
CP GmbH, Erkelenz and University of Applied Sciences Aachen, Aachen,
Germany
Dipl.-Ing. Josef Gockel (Chapter 2.2)
HASCO Hasenclever GmbH & Co. KG, Lüdenscheid, Germany
Ing. Rolf Hentrich (Chapter 1.6 and 4.3)
Lahr, Germany
Dipl.-Ing. (FH) Felix Hinken (Chapter 2.1)
Schneider Form GmbH, Dettingen/Teck, Germany
Dipl.-Ing. Udo Hinzpeter (Chapter 5.3)
Kunststoff -Institut Lüdenscheid; K.I.M.W. NRW GmbH, Lüdenscheid, Germany
VIII
Contributors
Dr.-Ing. Frank Hippenstiel (Chapter 3.1)
BGH Edelstahl Siegen GmbH, Siegen, Germany
Robert Hofmann (Chapter 1.11)
Hofmann Modellbau, Lichtenfels, Germany
Prof. Dipl.-Ing. Peter Karlinger (Chapter 2.1)
University of Applied Sciences Rosenheim, Rosenheim, Germany
Dipl.-Ing. (FH) Armin Klotzbücher (Chapter 4.1)
KWO Kunststoffteile GmbH, Offenau, Germany
Dr. Ulrich Knipp (Chapter 1.3)
Bergisch Gladbach, Germany
Günter Konzilia (Chapter 1.10)
z-werkzeugbau-gmbh, Dornbirn, Austria
Stefan Krüth (Chapter 4.6)
J. & F. Krüth GmbH, Solingen, Germany
Bernhard Mack (Chapter 4.2)
Mack Erodiertechnik, Langenau, Germany
Dr. Udo Maier (Chapter 1.3)
Pulheim, Germany
Prof. Dr.-Ing. Peter Mitschang (Chapter 1.8)
Institut für Verbundwerkstoffe GmbH, Kaiserslautern, Germany
Dipl.-Ing. Dirk Paulmann (Chapter 2.3)
HASCO Hasenclever GmbH & Co. KG, Lüdenscheid, Germany
Dipl.-Ing. Norbert Reuber (Chapter 1.7)
Kurtz GmbH, Kreuzwertheim, Germany
Dipl.-Ing. Manfred Sander (Chapter 2.3)
Iserlohn, Germany
Dipl.-Ing. (FH) Dietmar Schäffner (Chapter 4.2)
Viscoch GmbH, Widnau, Switzerland
Prof. Dr.-Ing. Alois K. Schlarb (Chapter 1.8)
University Kaiserslautern, Kaiserslautern, Germany
Prof. Dr.-Ing. Ralf Schledjewski (Chapter 1.8)
Montanuniversität Leoben, Leoben, Austria
Prof. Dr.-Ing. Friedhelm Schlößer (Chapter 5.1)
KION Group AG, Wiesbaden, Germany
Contributors
Edgar Seufert (Chapter 3.3)
Schmelzmetall Deutschland GmbH, Steinfeld-Hausen, Germany
Dipl.-Ing. Peter Schwarzmann (Chapter 1.5)
Illig Maschinenbau GmbH & Co. KG, Heilbronn, Germany
Claudia Steiner (Chapter 4.4)
NOVAPAX Kunststofftechnik Steiner GmbH & Co. KG, Berlin, Germany
Prof. Dr.-Ing. Paul Thienel (Chapter 2.4)
University of Applied Sciences Südwestfalen, Iserlohn, Germany
Uwe Thiesen (Chapter 5.4)
Plastics Germany GmbH & Co. KG, Lohne, Germany
Peter Vetter (Chapter 4.5)
Buderus Edelstahl GmbH, Wetzlar, Germany
Dipl.-Betriebsw. Oliver Wandres (Chapter 1.6)
Maus GmbH, Karlsruhe, Germany
Prof. Dipl.-Ing. Peter Wippenbeck (Chapter 1.1)
Steinbeis-Innovationszentrum Kunststofftechnik, Aalen, Germany
Klaus Zoller (Chapter 1.9)
Freudenberg Sealing Technologies GmbH & Co. KG, Weinheim, Germany
IX
Editor’s Preface
to the 3rd edition
When this book was first published in Carl Hanser Verlag in 1965 in German, edited
by K. Stoeckhert, a market gap was filled, because a second edition was already
required after four years, this time in collaboration with H. Domininghaus. The
third edition came eleven years later (1980), which already had almost twice the
number of pages. It was translated and became the 1 st English edition. Due to the
personnel change in the editorship, it then took 15 years until the next edition was
published with a slightly altered title in English and German. In addition a Chinese
edition was launched for the first time. Again it took some 15 years for the now
presented 3rd edition (the 5th in German) to be published.
The present edition is not only updated, but modernized and renewed. This is also
indicated by the fact that only six of the “old” authors are still involved, and there
are new chapters such as micro injection molds, molds for the rubber industry, or
rapid prototyping, while others are no longer applicable. Otherwise, as it was already
stated in the preface of the 4th German edition, it still applies that this compilation
does not intend to serve as a textbook for the detailed design of an injection mold
or to replace the catalogue of a manufacturer of standard mold units, and it is also
not the long version of a lecture manuscript either. Rather, the brief description of
the basic facts and the latest state of the art for the individual mold types and their
manufacture allow a direct comparison in a compact form.
The book still addresses both, the reader who is looking for an introduction to a
key area of plastics processing as well as the pronounced specialist to enable quick
reading into related technical areas, which can result in ideas for their own work.
Each chapter is self-contained; the proposed synergistic effect is achieved especially
when the reader not only reads “his” chapter, but is willing to “look outside the
box” of his own specialist field.
Chemnitz, April 2013
Günter Mennig
Contents
About the Book. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . V
Contributors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VII
Editor’s Preface to the 3rd edition.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . XI
1 Molds for Various Processing Methods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Injection Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
P. Wippenbeck
1.1.1General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1.2
Injection Molding Process. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1.3
Design of the Molded Part. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
1.1.4
Basic Mold Structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
1.1.5
Types of Ejection.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.1.5.1 Products without Undercuts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
1.1.5.2 Products with External Undercuts. . . . . . . . . . . . . . . . . . . . . . . . . 13
1.1.5.3 Product with Internal Undercuts. . . . . . . . . . . . . . . . . . . . . . . . . . . 17
1.1.5.4 Products with Internal Threads. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
1.1.6
Gate Technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1.1.6.1 Gate Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1.1.6.2 Solidifying Runner, Remaining at the Molded Part. . . . . . . . . . 23
1.1.6.3 Automatically Separated Runner. . . . . . . . . . . . . . . . . . . . . . . . . . . 26
1.1.6.4 Pass Through Channels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
1.1.6.5 Hotrunner Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
1.1.6.6 Hotrunner Nozzles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
1.1.7
Venting of the Cavity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
1.1.8
Temperature Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
1.1.9
Special Designs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
1.1.9.1 Stack Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
1.1.9.2 Injection-Compression Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
1.1.9.3 Multi-Component Technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
XIV
Contents
1.1.9.4 Outsert Technology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1.9.5 Molds for Thermosets and Elastomers. . . . . . . . . . . . . . . . . . . . . .
1.2 Compression and Transfer Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
J. Berthold
1.2.1Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.2
Compression Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.2.1 General Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.2.2Requirements.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.2.3 Components of a Compression Mold.. . . . . . . . . . . . . . . . . . . . . . .
1.2.3
Transfer Molding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.3.1General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.3.2Requirements.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.3.3 Structure of a Transfer Mold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.4
Making Compression Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.4.1Machining.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5
Mold Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.1 Types of Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.1.1 Small-Series Mold.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.1.2 Test Mold.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.1.3 Standard Mold Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.1.4 Conventional Compression Mold. . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2 Structural Mold Designs.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2.1 Positive Mold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2.2 Positive Mold with Lands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2.3 Multi-Cavity Mold with a Common Loading Chamber. . . . . . .
1.2.5.2.4 Multi-Cavity Mold with Individual Loading Chambers. . . . . . .
1.2.5.2.5 Mold with Lateral Core Puller.. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2.6 Split Mold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2.7 Hinged Split-Cavity Mold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2.8 Mold with Inserts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.2.9 Unscrewing Mold. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.5.3 General Aspects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.6
Sheet Molding Compound (SMC)-Molds. . . . . . . . . . . . . . . . . . . .
1.2.6.1Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.6.2 Mold Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.6.2.1 Mold Alignment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.6.2.2 Ejector Mechanism.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.6.2.3Undercuts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.6.2.4Heating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.7
GMT/LFT Molds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2.7.1Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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