ISO 7050:2011

Cross-recessed countersunk (flat) head tapping screws

ISO 7050:2011 specifies the characteristics of cross-recessed countersunk (flat) head tapping screws with thread sizes from ST 2,2 to ST 9,5 inclusive.

Vis à tôle à tête fraisée à empreinte cruciforme

L'ISO 7050:2011 spécifie les caractéristiques des vis à tôle à tête fraisée à empreinte cruciforme, de diamètre de filetage ST 2,2 à ST 9,5 inclus.

General Information

• Status: Published
• Publication Date: 20-Jul-2011
• ICS: 21.060.10 - Bolts, screws, studs
• Technical Committee: ISO/TC 2/SC 13 - Fasteners with non-metric thread
• Drafting Committee: ISO/TC 2/SC 13 - Fasteners with non-metric thread
• Current Stage: 9093 - International Standard confirmed
• Start Date: 29-Jun-2021
• Completion Date: 13-Dec-2025

Relations

• Consolidates: ISO 15590-2:2003 - Petroleum and natural gas industries - Induction bends, fittings and flanges for pipeline transportation systems - Part 2: Fittings
• Effective Date: 06-Jun-2022
• Revises: ISO 7050:1983 - Cross recessed countersunk (flat) head tapping screws (common head style)
• Effective Date: 17-Mar-2009

Overview

ISO 7050:2011 is an international standard published by the International Organization for Standardization (ISO) that specifies the characteristics of cross-recessed countersunk (flat) head tapping screws. This standard covers tapping screws with thread sizes ranging from ST 2.2 to ST 9.5 inclusive. It provides detailed requirements for dimensions, mechanical properties, thread types, head configurations, and materials, ensuring uniformity and compatibility across industries.

The 2011 edition is the second edition and replaces the first edition from 1983, incorporating technical revisions to reflect advances in manufacturing and fastener technology. ISO 7050:2011 plays a key role in standardizing tapping screws used in many mechanical and engineering applications for reliable fastening solutions.

Key Topics

• Thread Sizes Covered: Thread sizes from ST 2.2 up to ST 9.5 are specified, with detailed metric dimensions for pitch, diameter, and length.
• Head Type: Countersunk flat heads with cross recesses are standardized for aesthetic flush fittings and efficient drive engagement.
• Material Specifications:
  • Steel tapping screws conforming to ISO 2702 (heat-treated steel for mechanical properties)
  • Stainless steel variants compliant with ISO 3506-4 for mechanical properties and corrosion resistance.
• Cross Recess Types: Includes Type H and Type Z cross recesses with detailed specifications on penetration depth to ensure tool compatibility.
• Dimensional Tolerances: Defined according to ISO 4759-1, which governs acceptable limits for product grades (A, B, and C).
• Surface Coatings and Treatments: Requirements for electroplated coatings (ISO 4042), passivation treatments for stainless steel (ISO 16048), and zinc flake coatings (ISO 10683) are included to enhance corrosion resistance.
• Acceptance Inspection: Inspection protocols per ISO 3269 guarantee product quality and conformance.
• Designation System: Clear format provided for specifying screws by thread size, length, material grade, end type, and cross recess type.

Applications

ISO 7050:2011 tapping screws are widely used in industries requiring secure fastening with precise dimensions and mechanical reliability. Typical applications include:

• Electronics Assembly: Small-size tapping screws ensure compact and secure fittings in devices with tight tolerances.
• Automotive Manufacturing: Consistent fasteners with specified corrosion resistance enable durable vehicle assemblies.
• Construction and Building: Countersunk flat heads provide smooth surfaces in metal and wood fastening.
• Appliance Production: Screws meeting ISO 7050 enable standardized repairs and maintenance.
• Machinery and Equipment: These screws allow for efficient assembly and disassembly of components requiring reliable fastening.

Their standardized specifications support interchangeability and quality assurance in high-volume manufacturing and engineering projects worldwide.

Related Standards

ISO 7050:2011 references and works in conjunction with several critical ISO standards to ensure comprehensive requirements and interoperability:

• ISO 225: Symbols and descriptions of dimensions for bolts, screws, studs, and nuts.
• ISO 1478: Specifications for tapping screw threads.
• ISO 2702: Mechanical properties for heat-treated steel tapping screws.
• ISO 3506-4: Mechanical properties for corrosion-resistant stainless steel tapping screws.
• ISO 4042: Requirements for electroplated coatings on fasteners.
• ISO 10683: Non-electrolytic zinc flake coating standards.
• ISO 16048: Passivation methods for stainless steel fasteners.
• ISO 4757 and ISO 7721-2: Specifications for cross recesses and countersunk head dimensions.
• ISO 4759-1: Tolerances for fastener dimensions and product grades.
• ISO 3269: Acceptance inspection procedures for fasteners.

These related standards complement ISO 7050 by covering mechanical properties, coatings, dimensions, and quality checks, creating a robust framework for reliable tapping screw manufacturing and use.

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By adhering to ISO 7050:2011, manufacturers and users ensure tapping screws that meet international quality and compatibility standards, facilitating global trade and consistent performance in various technical applications. Keywords: ISO 7050 tapping screws, cross-recessed countersunk screws, tapping screw dimensions, stainless steel tapping screws, fastening standards, mechanical fasteners, tapping screw specifications.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 7050
Second edition
2011-08-01
Cross-recessed countersunk (flat) head
tapping screws
Vis à tôle à tête fraisée à empreinte cruciforme

Reference number
©
ISO 2011
©  ISO 2011
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
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2011 – All rights reserved

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 7050 was prepared by Technical Committee ISO/TC 2, Fasteners, Subcommittee SC 13, Fasteners with
non-metric thread.
This second edition cancels and replaces the first edition (ISO 7050:1983), which has been technically revised.

INTERNATIONAL STANDARD ISO 7050:2011(E)

Cross-recessed countersunk (flat) head tapping screws
1 Scope
This International Standard specifies the characteristics of cross-recessed pan head tapping screws with
thread sizes from ST 2,2 to ST 9,5 inclusive.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 225, Fasteners — Bolts, screws, studs and nuts — Symbols and descriptions of dimensions
ISO 1478, Tapping screws thread
ISO 2702, Heat-treated steel tapping screws — Mechanical properties
ISO 3269, Fasteners — Acceptance inspection
ISO 3506-4, Mechanical properties of corrosion-resistant stainless steel fasteners — Part 4: Tapping screws
ISO 4042, Fasteners — Electroplated coatings
ISO 4757, Cross recesses for screws
ISO 4759-1, Tolerances for fasteners — Part 1: Bolts, screws, studs and nuts — Product grades A, B and C
ISO 7721, Countersunk head screws — Head configuration and gauging
ISO 7721-2, Countersunk flat head screws — Part 2: Penetration depth of cross recesses
ISO 8992, Fasteners — General requirements for bolts, screws, studs and nuts
ISO 10683, Fasteners — Non-electrolytically applied zinc flake coatings
ISO 16048, Passivation of corrosion-resistant stainless-steel fasteners
------------
...

NORME ISO
INTERNATIONALE 7050
Deuxième édition
2011-08-01
Vis à tôle à tête fraisée à empreinte
cruciforme
Cross-recessed countersunk (flat) head tapping screws

Numéro de référence
©
ISO 2011
DOCUMENT PROTÉGÉ PAR COPYRIGHT

©  ISO 2011
Droits de reproduction réservés. Sauf prescription différente, aucune partie de cette publication ne peut être reproduite ni utilisée sous
quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et les microfilms, sans l'accord écrit
de l'ISO à l'adresse ci-après ou du comité membre de l'ISO dans le pays du demandeur.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Publié en Suisse
ii © ISO 2011 – Tous droits réservés

Avant-propos
L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes nationaux de
normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est en général confiée
aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude a le droit de faire partie du
comité technique créé à cet effet. Les organisations internationales, gouvernementales et non
gouvernementales, en liaison avec l'ISO participent également aux travaux. L'ISO collabore étroitement avec
la Commission électrotechnique internationale (CEI) en ce qui concerne la normalisation électrotechnique.
Les Normes internationales sont rédigées conformément aux règles données dans les Directives ISO/CEI,
Partie 2.
La tâche principale des comités techniques est d'élaborer les Normes internationales. Les projets de Normes
internationales adoptés par les comités techniques sont soumis aux comités membres pour vote. Leur
publication comme Normes internationales requiert l'approbation de 75 % au moins des comités membres
votants.
L'attention est appelée sur le fait que certains des éléments du présent document peuvent faire l'objet de
droits de propriété intellectuelle ou de droits analogues. L'ISO ne saurait être tenue pour responsable de ne
pas avoir identifié de tels droits de propriété et averti de leur existence.
L'ISO 7050 a été élaborée par le comité technique ISO/TC 2, Éléments de fixation, sous-comité SC 13,
Éléments de fixation à filetage non métrique.
Cette deuxième édition annule et remplace la première édition (ISO 7050:1983), qui a fait l'objet d'une
révision technique.
NORME INTERNATIONALE ISO 7050:2011(F)

Vis à tôle à tête fraisée à empreinte cruciforme
1 Domaine d'application
La présente Norme internationale spécifie les caractéristiques des vis à tôle à tête fraisée à empreinte
cruciforme, de diamètre de filetage ST 2,2 à ST 9,5 inclus.
2 Références normatives
Les documents de référence suivants sont indispensables pour l'application du présent document. Pour les
références datées, seule l'édition citée s'applique. Pour les références non datées, la dernière édition du
document de référence s'applique (y compris les éventuels amendements).
ISO 225, Éléments de fixation — Vis, goujons et écrous — Symboles et description des dimensions
ISO 1478, Filetage de vis à tôle
ISO 2702, Vis à tôle en acier traité thermiquement — Caractéristiques mécaniques
ISO 3269, Éléments de fixation — Contrôle de réception
ISO 3506-4, Caractéristiques mécaniques des éléments de fixation en acier inoxydable résistant à la
corrosion — Partie 4: Vis à tôle
ISO 4042, Éléments de fixation — Revêtements électrolytiques
ISO 4757, Empreintes cruciformes pour vis
ISO 4759-1, Tolérances des éléments de fixation — Partie 1: Vis, goujons et écrous — Grades A, B et C
ISO 7721, Vis à tête fraisée — Configuration de la tête et vérification par calibre
ISO 7721-2, Vis à métaux à tête fraisée — Partie 2: Profondeur de pénétration des empreintes cruciformes
ISO 8992, Éléments de fixation — Exigences générales pour vis, goujons et écrous
ISO 10683, Éléments de fixation — Revêtements non électrolytiques de lamelles de zinc
ISO 16048, Passivation des éléments de fixation en acier
...