EN ISO 8742:1997

Grooved pins - One-third-length centre grooved (ISO 8742:1997)

Knebelkerbstifte mit kurzen Kerben (ISO 8742:1997)

Diese Internationale Norm beschreibt die Eigenschaften von Knebelkerbstiften aus Stahl oder austenitischem nichtrostendem Stahl, mit kurzen Kerben, mit drei gleichmäßig verteilten Längskerben auf der Außenfläche. Die Kerbstifte haben einen Nenndurchmesser d1, von 1,5 mm bis einschließlich 25 mm. Der zu jeder Seite der Kerbe verdrängte Werkstoff, der den aufgeweiterten Durchmesser d2 bildet, welcher größer als dder Nenndurchmesser d1 ist, führt zu einer kraftschlüssigen Verbindung, wenn diese Kerbstifte in eine Bohrung mit einem Durchmesser gleich dem Nenndurchmesser d1 gepreßt werden

Goupilles cannelées à cannelures centrales constantes sur le tiers de la longueur non débouchantes (ISO 8742:1997)

La présente Norme internationale prescrit les caractéristiques des goupilles cannelées en acier ou en acier inoxydable austénitique, à trois cannelures centrales constantes sur le tiers de leur longueur, non débouchantes et régulièrement espacées, de diamètre nominal, d1, de 1,5 mm à 25 mm inclus. Le matériau refoulé de chaque côté des cannelures forme un renflement dont le diamètre d2, supérieur au diamètre nominal d1, permet un ajustement serré de ces goupilles cannelées lorsqu'elles sont emmanchées en force dans un trou de diamètre de perçage égal au diamètre nominal de la goupille d1 (voir article 4).

Zasekani zatiči z brazdami enake globine na tretjini dolžine v sredini (ISO 8742:1997)

General Information

• Status: Published
• Publication Date: 31-Oct-1997
• ICS: 21.060 - Fasteners
• Technical Committee: CEN/TC 185 - Threaded and nonthreaded mechanical fasteners and accessories
• Drafting Committee: CEN/TC 185 - Threaded and nonthreaded mechanical fasteners and accessories
• Current Stage: 9093 - Decision to confirm - Review Enquiry
• Start Date: 04-Feb-2008
• Completion Date: 04-Feb-2008
• Ref Project: SIST EN ISO 8742:2001 - Grooved pins - One-third-length centre grooved (ISO 8742:1997)

Relations

• Replaces: EN 28742:1992 - Grooved pins - Third-length centre grooved (ISO 8742:1986)
• Effective Date: 22-Dec-2008
• Revised: prEN ISO 8742 - Fasteners - Grooved pins - One-third-length center grooves (ISO/DIS 8742:2025)
• Effective Date: 05-Nov-2024
• Revised: prEN ISO 8742 - Fasteners - Grooved pins - One-third-length center grooves (ISO/DIS 8742:2023)
• Effective Date: 18-Jan-2023

Overview

EN ISO 8742:1997 is an internationally recognized standard developed by the International Organization for Standardization (ISO) and adopted by CEN. This standard specifies the technical characteristics and requirements for one-third-length centre grooved pins constructed primarily from steel or austenitic stainless steel. These grooved pins feature three equally spaced longitudinal grooves along one-third of their length, designed to provide a reliable, non-positive locking fit when inserted into drilled holes.

The standard covers pin diameters ranging from 1.5 mm to 25 mm, detailing dimensions, materials, surface treatments, mechanical properties, and testing methods essential to ensure consistent quality and performance in industrial fastening applications.

---

Key Topics

• Pin Dimensions and Grooving

  • Nominal diameters from 1.5 mm to 25 mm.
  • Three equidistant longitudinal grooves on the central third length.
  • The grooves create an expanded diameter exceeding the nominal size, allowing for a secure non-positive locking fit in a corresponding hole.

• Materials and Hardness

  • Steel: hardness range 125 HV30 to 245 HV30.
  • Austenitic stainless steel: hardness range 210 HV30 to 280 HV30 compliant with ISO 3506-1.
  • Material choice affects groove angle and expanded diameter dimensions.

• Surface Finish and Coatings

  • Pins typically supplied in natural finish or with protective coatings.
  • Accepted coatings include black oxide, phosphate coatings, or zinc plating with chromate conversion.
  • All coatings must comply with referenced standards ISO 9717 and ISO 4042.

• Mechanical Requirements

  • Defined minimum shear strength requirements for different sizes (expressed in kN).
  • Acceptance inspection based on ISO 3269.
  • Shear testing conducted according to ISO 8749.

• Design and Workmanship

  • Groove form can vary but must ensure proper function.
  • Pins must be free from defects or irregularities affecting performance.

• Hole Tolerance for Installation

  • The drilled hole must match the nominal pin diameter to tolerance class H11 to ensure correct fit.

---

Applications

EN ISO 8742 grooved pins are widely used in mechanical engineering and manufacturing sectors for:

• Locating and Fastening Components
  Ensuring precise alignment and secure locking in assemblies subject to shear forces.

• Machinery and Equipment Assembly
  Enable quick and reliable joining of parts without threaded fasteners-ideal for applications requiring repeatable and robust connections.

• Automotive and Aerospace Industries
  Provide consistent and measurable mechanical reliability critical in safety and performance-sensitive applications.

• General Industrial Use
  Applies to any product requiring economical and efficient pin fasteners with secure locking and shear resistance.

---

Related Standards

• ISO 3269:1988 – Fasteners: Acceptance inspection procedures for quality verification.
• ISO 3506-1:1997 – Corrosion-resistant stainless steel fasteners specifications.
• ISO 4042 – Fasteners: Electroplated coatings (foreseen revision pending).
• ISO 8749:1986 – Pins and grooved pins shear strength testing methods.
• ISO 9717:1990 – Phosphate conversion coatings requirements for metals.

---

EN ISO 8742:1997 ensures a globally harmonized approach for manufacturing and quality assurance of one-third-length centre grooved pins. This facilitates compatibility, interchangeability, and reliable performance across industries relying on precision fasteners. Utilizing this standard improves product quality, assembly efficiency, and long-term durability in mechanical connections.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2001
1DGRPHãþD
SIST EN 28742:1996
=DVHNDQL]DWLþL]EUD]GDPLHQDNHJORELQHQDWUHWMLQLGROåLQHYVUHGLQL,62

Grooved pins - One-third-length centre grooved (ISO 8742:1997)
Knebelkerbstifte mit kurzen Kerben (ISO 8742:1997)
Goupilles cannelées a cannelures centrales constantes sur le tiers de la longueur non
débouchantes (ISO 8742:1997)
Ta slovenski standard je istoveten z: EN ISO 8742:1997
ICS:
21.060.50 =DWLþLåHEOML Pins, nails
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL ISO
STANDARD 8742
Second edition
1997-11-01
Grooved pins — One-third-length centre
grooved
Goupilles cannelées à cannelures centrales constantes sur le tiers
de la longueur non débouchantes
.
A
Reference number
ISO 8742:1997(E)
ISO 8742:1997(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.
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.
International Standard ISO 8742 was prepared by Technical Committee
ISO/TC 2, Fasteners.
This second edition cancels and replaces the first edition (ISO 8742:1986),
which has been technically revised.
©  ISO 1997
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 the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet [e-mail]
X.400 c=ch; a=400net; p=iso; o=isocs; s=central
Printed in Switzerland
ii
©
INTERNATIONAL STANDARD  ISO ISO 8742:1997(E)
Grooved pins — One-third-length centre grooved
1 Scope
This International Standard specifies the characteristics of one-third-length centre grooved pins made of steel
or austenitic stainless steel which have three equally spaced grooves impressed longitudinally on their
exterior surface, with nominal diameter, d , from 1,5 mm to 25 mm inclusive.
The displaced material to each side of the grooves forming an expanded diameter, d , which is larger than the
nominal diameter d will cause a non-positive locking fit when these grooved pins are forced into a drilled hole
equal to the nominal diameter d (see clause 4).
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this
International Standard. At the time of publication, the editions indicated were valid. All standards are subject
to revision, and parties to agreements based on this International Standard are encouraged to investigate the
possibility of applying the most recent editions of the s
...