ISO 3353-1:2020

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 3353-1
ISO/TC 20/SC 4
Aerospace — Lead and runout
Secretariat: DIN
threads —
Voting begins on:
2020-09-29
Part 1:
Voting terminates on:
Rolled external threads
2020-11-24
Aéronautique et espace — Filets incomplets, débuts et fins de filets —
Partie 1: Filetages extérieurs roulés
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 SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 3353-1:2020(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. ISO 2020

---------------------- Page: 1 ----------------------
ISO/FDIS 3353-1:2020(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2020
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 2020 – All rights reserved

---------------------- Page: 2 ----------------------
ISO/FDIS 3353-1:2020(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols for threads . 2
5 Requirements . 2
5.1 General requirements . 2
5.2 Lead threads . 2
5.3 Runout threads . 3
5.3.1 Normal shank . 3
5.3.2 Pitch diameter shank . 4
5.3.3 Stepped shank . 4
5.3.4 Screws threaded to the head and bolts threaded to a shoulder . 5
5.3.5 Oversized bolts . 6
6 Inspection method . 7
6.1 General . 7
6.2 Use of the charts . 7
6.3 Procedure . 7
6.3.1 For lead threads . 7
6.3.2 For runout threads . 7
Annex A (informative) Comments on inspection method .10
© ISO 2020 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO/FDIS 3353-1:2020(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/d irectives).
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/p atents).
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/f oreword. html.
This document was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles
Subcommittee SC 4, Aerospace fastener systems.
This second edition cancels and replaces the first edition (ISO 3353-1:2002), of which it constitutes a
minor revision.
The main changes compared to the previous edition are as follows:
— update of the term “lead threads”;
— editorially revised.
A list of all parts in the ISO 3353 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national
...