ISO 23509-2016 PDF

Full title and description

St ISO 23509-2016 — Bevel and hypoid gear geometry. International standard that defines geometric definitions, symbols and calculation methods for bevel and hypoid gears (straight, spiral, Zerol and hypoid forms), intended to provide a consistent basis for design, drawing, manufacture-neutral geometry specifications and for geometry inputs used in gear-rating calculations.

Abstract

ISO 23509:2016 specifies the geometry of bevel and hypoid gears, covering straight, spiral, Zerol and hypoid designs. The standard is manufacturing-process neutral and provides geometric definitions, formulae and calculation structure (Annex A) required to describe gear macro-geometry and to generate values used in bevel-gear rating calculations (for example, factors used in ISO 10300). It is intended primarily for experienced gear designers and specialists rather than the general engineering public.

General information

• Status: Withdrawn (superseded).
• Publication date: November 2016 (Edition 2, published 2016-11).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 21.200 — Gears.
• Edition / version: Edition 2 (2016).
• Number of pages: 138.

Scope

This standard defines the geometric parameters, coordinate definitions, symbols and calculation methods necessary to describe the macro-geometry of bevel and hypoid gears (including straight, skew, spiral and Zerol bevel designs and hypoid gears). It covers cone angles, spiral angles, pitch definitions, tooth thickness and spacing conventions, offsets and axis arrangements required for consistent geometry specification and for producing inputs to gear-rating procedures. The document is neutral with respect to manufacturing process and is intended to be used by gear designers and specialists to select and compute appropriate geometry values.

Key topics and requirements

• Definitions and symbol set for bevel and hypoid gear geometry (cone angles, spiral angle, pitch, tooth thickness, offsets, axis angle conventions).
• Calculation methods and formulae for deriving geometric parameters across straight, spiral, Zerol and hypoid forms.
• Geometry conventions and coordinate systems suitable for specification, drawing and digital transfer.
• Structure for organized calculations (Annex A) to support programmatic and manual computation of geometry.
• Provision of geometry required for gear-rating factor calculations (compatible with ISO 10300 series).
• Guidance on selecting appropriate parameter values, intended for experienced gear designers rather than general users.

Typical use and users

Used by gear designers, drivetrain and transmission engineers, gear-manufacturing technical staff, gear-design software developers, research organizations and standards committees. Typical applications are initial geometry definition for bevel/hypoid gear sets, pre-dimensioning, preparation of geometry inputs for strength and contact rating calculations, and ensuring consistent geometric data exchange between design, analysis and manufacturing systems.

Related standards

ISO 23509:2016 has been revised and its content superseded by ISO 23509-1:2025 (Part 1: Basic methods). It is directly related to gear-rating and calculation standards such as the ISO 10300 series (factors used in gear rating). It also sits in the work programme of ISO/TC 60 (Gears) and its subcommittees. National adoptions and related guidance documents from national standards bodies and industry bodies on bevel/hypoid gear geometry and rating are commonly used alongside this standard.

Keywords

Bevel gear, hypoid gear, Zerol bevel, spiral bevel, gear geometry, cone angle, spiral angle, pitch, tooth thickness, gear calculation, ISO 10300, bevel gear pre-dimensioning.

FAQ

Q: What is this standard?

A: ISO 23509:2016 is an international standard that defines the geometry, symbols and calculation methods for bevel and hypoid gears (straight, spiral, Zerol and hypoid types).

Q: What does it cover?

A: It covers geometric definitions, coordinate and angle conventions, formulae for computing geometric parameters, and a calculation structure (Annex A) to produce consistent geometry data suitable for design, manufacture-neutral specification and input to gear-rating calculations.

Q: Who typically uses it?

A: Experienced gear designers, transmission engineers, gear-manufacturing engineers, designers of gear-analysis software, researchers and standards bodies that need consistent bevel/hypoid geometry definitions.

Q: Is it current or superseded?

A: ISO 23509:2016 has been withdrawn and superseded. The material was revised and published as ISO 23509-1:2025 (Part 1: Basic methods), published in July 2025; users should refer to the 2025 Part 1 publication for the current, published methods.

Q: Is it part of a series?

A: The 2016 edition was a standalone edition covering bevel and hypoid gear geometry. The content has since been reorganized into a multi-part structure under ISO 23509-1:2025 (Part 1: Basic methods); further parts or related documents may be published by ISO/TC 60 in the series covering additional methods or details.

Q: What are the key keywords?

A: Bevel gear, hypoid gear, spiral bevel, Zerol, gear geometry, cone angle, spiral angle, pitch, tooth form, gear calculation, ISO 10300.