ISO 4757-1983 PDF

Full title and description

ISO 4757:1983 — Cross recesses for screws. Specifies the geometric forms, dimensions and gauging method for two types of cruciform (cross) recesses used in screw heads (type H and type Z), with tables and figures covering sizes from No. 0 to No. 4 and a method of penetration gauging to check driver engagement.

Abstract

This International Standard defines two cross-recess types (H and Z) for screws, gives dimensional illustrations and tabulated gauge dimensions for sizes No. 0 up to No. 4 inclusive, and includes a method for penetration gauging applicable to both types. The document is concise (9 pages) and intended for use in specification, production and inspection of cruciform-head fasteners.

General information

• Status: Published — international standard (confirmed in a 2023 review; the 1983 edition remains current).
• Publication date: 1 August 1983 (Edition 1, 1983).
• Publisher: ISO (International Organization for Standardization).
• ICS / categories: 21.060.10 (Bolts, screws, studs).
• Edition / version: Edition 1 (1983).
• Number of pages: 9.

Key bibliographic and status details are recorded on the ISO bibliographic entry for ISO 4757:1983.

Scope

ISO 4757:1983 specifies the form and dimensions of two types of cross recesses for screw heads (designated H and Z), provides graphical illustrations and tables of gauge dimensions for sizes No. 0 through No. 4, and defines a penetration-gauging method to verify the recess-driver engagement. It is intended to standardize recess geometry so that drivers and gauges can be made and used consistently across manufacturers and inspection laboratories.

Key topics and requirements

• Definition and pictorial representation of cross-recess types H and Z.
• Dimensional tables (gauge dimensions) for recess sizes No. 0 to No. 4 inclusive.
• Figures illustrating recess geometry and dimensional tolerances.
• Method of penetration gauging to assess driver engagement and recess acceptability.
• Normative specification intended for manufacturers, tool designers and quality inspectors to ensure interchangeability of drivers and screw heads.

These requirements and topics are summarized in the ISO document and in subsequent national/adopted versions.

Typical use and users

Primary users are fastener manufacturers, tool (driver) designers, assembly-tooling engineers, quality control and metrology laboratories, procurement/specification engineers, and standards committees dealing with fasteners and tooling. The standard is used when specifying screw head recess geometry for production drawings, driver design, inspection procedures and procurement documents.

Related standards

ISO 4757:1983 has been adopted in various regional and national forms (for example as EN ISO 4757 in the 1990s and corresponding national adoptions such as DIN EN ISO 4757 and BS EN ISO 4757). Related documents include the European adoptions and later national transpositions that reproduce ISO 4757 content for regional use.

Keywords

cross recess, cruciform recess, screw head, driver engagement, penetration gauging, type H, type Z, fasteners, screws, ICS 21.060.10.

FAQ

Q: What is this standard?

A: ISO 4757:1983 is an International Standard titled "Cross recesses for screws" that defines the geometry, dimensions and a gauging method for two types of cruciform recesses used in screw heads (types H and Z).

Q: What does it cover?

A: It covers the form and dimensions of cross recesses (H and Z), tabulated gauge sizes No. 0–4, illustrative figures, tolerances and a method of penetration gauging to verify proper driver engagement.

Q: Who typically uses it?

A: Fastener manufacturers, tool and driver designers, assembly and production engineers, quality/inspection laboratories, purchasers specifying fasteners, and standards bodies adopting the ISO content nationally or regionally.

Q: Is it current or superseded?

A: The ISO bibliographic record shows ISO 4757:1983 was reviewed and confirmed in 2023; the 1983 edition therefore remains the current ISO edition. Regional adoptions (EN/DIN/BS versions) have been published in the 1990s. Users should check national catalogues for any later amendments or national-only changes before quoting the standard in procurement.

Q: Is it part of a series?

A: ISO 4757:1983 is a standalone ISO document specific to cross recesses for screws but is related by subject to other ISO standards and regional/adopted documents covering fasteners and head forms; it has been incorporated into European/national adoptions (EN ISO, DIN EN, BS EN).

Q: What are the key keywords?

A: Cross recess, cruciform, screw head, type H, type Z, penetration gauging, fasteners, screw recess dimensions (ICS 21.060.10).