SIST EN ISO 888:2018

Fasteners - Bolts, screws and studs - Nominal lengths and thread lengths (ISO 888:2012)

ISO 888:2012 specifies lengths and thread lengths for bolts, screws and studs for use in appropriate product standards and other relevant documents, e.g. for parts per drawing.
It applies to bolts, screws and studs with ISO metric screw thread according to ISO 68-1.

Verbindungselemente - Schrauben - Nenn- und Gewindelängen (ISO 888:2012)

Fixations - Vis, goujons et tiges filetées - Longueurs nominales et longueurs filetées (ISO 888:2012)

Vezni elementi - Sorniki, vijaki in zatiči - Imenske dožine in dolžine navoja (ISO 888:2012)

Standard ISO 888:2012 določa dolžine in dolžine navoja za sornike, vijake ter zatiče, ki se uporabljajo v ustreznih standardih za proizvode in drugih zadevnih dokumentih, npr. za dele na sliko.
Uporablja se za sornike, vijake in zatiče z metričnim navojem ISO v skladu s standardom ISO 68-1.

General Information

• Status: Published
• Public Enquiry End Date: 13-Sep-2017
• Publication Date: 10-Sep-2018
• ICS: 21.060.10 - Bolts, screws, studs
• Technical Committee: ISEL - Mechanical elements
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 26-Jul-2018
• Due Date: 30-Sep-2018
• Completion Date: 11-Sep-2018
• Ref Project: EN ISO 888:2018 - Fasteners - Bolts, screws and studs - Nominal lengths and thread lengths (ISO 888:2012)

Overview

EN ISO 888:2018 (ISO 888:2012) - Fasteners: bolts, screws and studs - nominal lengths and thread lengths.
This CEN-adopted standard specifies how to define and dimension nominal lengths and thread lengths for bolts, screws and studs with ISO metric screw thread (per ISO 68-1). It is intended for use in product standards, technical drawings and other documents that specify fastener geometry.

Key topics and technical requirements

• Scope: Applies to ISO metric threaded bolts, screws and studs; defines measurement positions and dimensioning rules for lengths and thread lengths.
• Normative references: ISO 68-1 (metric thread profile), ISO 225 (symbols and descriptions), ISO 4753 (thread ends), ISO 4759-1 (tolerances for fasteners).
• Symbols & definitions: Nominal length (l), thread length (b), basic major diameter (d), thread pitch (P) and related terms used consistently for dimensioning.
• Position of lengths: Clear measurement rules for different head and end types:
  • Bolts/screws with bearing face - length from bearing face to end.
  • Flat countersunk and raised countersunk heads - length from head reference surface to end.
  • Concave/serrated bearing surfaces - from effective bearing plane.
  • Headless/set screws and fully threaded studs - length from end to end.
  • Partially threaded studs/double-end studs - length from thread run-out to nut end, etc.
• Thread length calculation: Default thread length b is calculated unless a product standard specifies otherwise:
  • For l ≤ 125 mm: b = 2d + 6 mm
  • For 125 mm < l ≤ 200 mm: b = 2d + 12 mm
  • For l > 200 mm: b = 2d + 25 mm
  • If the unthreaded shank would be ≤ 0.5d, the fastener should be fully threaded.
• Tolerances: Tolerances for lengths and thread lengths are handled according to ISO 4759-1 and also referenced in ISO 225 for particular head/drive types.

Applications

• Standardizes how fastener dimensions are specified on drawings and in product standards, ensuring interchangeability and correct fit.
• Useful when specifying bolted joints, assemblies, fastener procurement, and quality inspection criteria.
• Helps determine when a bolt should be fully threaded versus partially threaded based on length-to-diameter relationships.

Who uses this standard

• Fastener manufacturers and suppliers
• Mechanical designers and OEMs specifying hardware on drawings
• Standards committees and technical authors writing product standards
• Quality engineers and inspectors verifying fastener dimensions
• Purchasing and procurement teams ensuring correct part specifications

Related standards

• ISO 68-1 (Metric screw threads - basic profile)
• ISO 225 (Fasteners - symbols and descriptions)
• ISO 4753 (Ends of threaded parts)
• ISO 4759-1 (Tolerances for fasteners - product grades)

Keywords: EN ISO 888:2018, ISO 888:2012, fasteners, bolts, screws, studs, nominal lengths, thread lengths, ISO metric screw thread, thread length calculation.

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2018
9H]QLHOHPHQWL6RUQLNLYLMDNLLQ]DWLþL,PHQVNHGRåLQHLQGROåLQHQDYRMD,62

Fasteners - Bolts, screws and studs - Nominal lengths and thread lengths (ISO
888:2012)
Verbindungselemente - Schrauben - Nenn- und Gewindelängen (ISO 888:2012)
Fixations - Vis, goujons et tiges filetées - Longueurs nominales et longueurs filetées (ISO
888:2012)
Ta slovenski standard je istoveten z: EN ISO 888:2018
ICS:
21.060.10 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 888
EUROPEAN STANDARD
NORME EUROPÉENNE
June 2018
EUROPÄISCHE NORM
ICS 21.060.10
English Version
Fasteners - Bolts, screws and studs - Nominal lengths and
thread lengths (ISO 888:2012)
Fixations - Vis, goujons et tiges filetées - Longueurs Verbindungselemente - Schrauben - Nenn- und
nominales et longueurs filetées (ISO 888:2012) Gewindelängen (ISO 888:2012)
This European Standard was approved by CEN on 23 April 2018.

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: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 888:2018 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
European foreword
The text of ISO 888:2012 has been prepared by Technical Committee ISO/TC 2 “Fasteners” of the
International Organization for Standardization (ISO) and has been taken over as EN ISO 888:2018 by
Technical Committee CEN/TC 185 “Fasteners” the secretariat of which is held by BSI.
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 2018, and conflicting national standards
shall be withdrawn at the latest by December 2018.
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.
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 888:2012 has been approved by CEN as EN ISO 888:2018 without any modification.

INTERNATIONAL ISO
STANDARD 888
Second edition
2012-04-15
Fasteners — Bolts, screws and studs —
Nominal lengths and thread lengths
Fixations — Vis, goujons et tiges filetées — Longueurs nominales et
longueurs filetées
Reference number
ISO 888:2012(E)
©
ISO 2012
ISO 888:2012(E)
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
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Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

ISO 888:2012(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Symbols . 1
4 Position of lengths and thread lengths . 1
4.1 General . 1
4.2 Bolts and screws . 2
4.3 Headless screws and set screws . 3
4.4 Studs and similar fasteners . 3
5 Dimensions for lengths . 5
6 Dimensions for thread lengths . 6
ISO 888:2012(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 888 was prepared by Technical Committee ISO/TC 2, Fasteners, Subcommittee SC 7, Reference standards.
This second edition cancels and replaces the first edition (ISO 888:1976), which has been technically revised.
iv © ISO 2012 – All rights reserved

INTERNATIONAL STANDARD ISO 888:2012(E)
Fasteners — Bolts, screws and studs — Nominal lengths and
thread lengths
1 Scope
This International Standard specifies lengths and thread length
...