GOST 19274-73 PDF

Full title and description

GOST 19274-73 — Передачи зубчатые цилиндрические эвольвентные внутреннего зацепления. Расчет геометрии. Standard for the geometric calculation of cylindrical involute internal gear pairs (defines methods, formulas and drawing parameters for internal involute gear sets).

Abstract

This GOST specifies the method for calculating geometric and kinematic parameters of cylindrical involute internal gear pairs with constant transmission ratio. It covers nominal dimensions, tooth geometry, checks for interference and cutting-tool-related constraints, and the parameters to be shown on working drawings in accordance with drawing rules. The standard applies to straight- and helical-tooth internal gears, with and without profile modification, and includes recommendations and verification procedures to ensure manufacturability and correct meshing.

General information

• Status: Active (Действует); limitation of validity removed by subsequent resolution.
• Publication date: Approved 1973; introduced (effective) 01 January 1975; reprinted June 1992.
• Publisher: State Committee for Standards of the USSR (Gosstandart) — published as a USSR / Interstate (GOST) standard.
• ICS / categories: OKS/ICS 21.200 (Gears / mechanical systems and components for general use).
• Edition / version: Original designation GOST 19274-73 (1973); effective from 1975; later reprints/editions (e.g., 1992 reprint) retained the original designation.
• Number of pages: Approximately 65–66 pages (varies by publisher/reprint).

Scope

Applies to cylindrical involute internal gear pairs with constant gear ratio. Establishes calculation procedures for nominal geometric parameters of the gear pair and individual wheels (modules, pitch diameters, tip/root diameters, tooth thickness by chord and arc, pressure angles, helix/lead for helical gears, centers/clearances), and prescribes the parameters to be indicated on working drawings. Includes methods to check for interference and for manufacturability when using standard cutting tools (e.g., broaches or cutters) and gives special rules for cases with profile modification or rounded tool edges.

Key topics and requirements

• Definitions and notation for internal involute gear geometry consistent with related gear GOSTs.
• Formulas and step-by-step procedures to calculate nominal geometric parameters (module, number of teeth, pitch diameters, addendum/dedendum, working depth, tooth thickness by chord, space width, etc.).
• Calculation rules for straight-tooth (spur) and helical internal gears, including helix angle and axial lead relations.
• Verification methods for interference between mating teeth and for absence of undercut or excessive trimming when manufactured by standard tools.
• Guidance on allowable profile modifications (head/profile shifts) and their influence on geometry and assembly clearances.
• Requirements for values and tolerances to be shown on working drawings in accordance with drawing standard GOST 2.403-75.
• Nomograms, tables and graphical checks (where applicable) to simplify routine design and interference checks.

Typical use and users

Used by mechanical designers, gear engineers and specialists in machine-tooling and transmission design for calculating and documenting internal gear geometry. Typical users include gear manufacturers, tractor/automotive/industrial gearbox designers, toolmakers (broaches and cutters), testing and quality departments, standards bodies, and technical educators teaching gear design and manufacturing.

Related standards

Commonly used together with other GOSTs covering gear geometry, reference contours, cutting tools and drawing rules — for example GOST 16532 (external involute gear calculation and related rules), GOST 13755 (reference contours), GOST 2.403-75 (working drawing rules), and standards for gear cutting tools and processes. When designing to international practice, designers also reference relevant ISO/IEC gear standards for compatibility with international specifications.

Keywords

GOST 19274-73; internal gear; involute; cylindrical gears; gear geometry; interference check; module; tooth thickness; addendum; dedendum; gear calculation; spur gear; helical gear; Gosstandart.

FAQ

Q: What is this standard?

A: GOST 19274-73 is a Soviet / interstate standard that defines the calculation of geometric parameters for cylindrical involute internal gear pairs (design and drawing parameters for internal gears).

Q: What does it cover?

A: It covers formulas, procedures and verification methods to compute nominal dimensions (module, pitch and tip/root diameters, tooth thickness by chord/arc, pressure angles, helix parameters), checks for interference and manufacturability, and the parameters to be indicated on working drawings.

Q: Who typically uses it?

A: Gear designers, mechanical engineers, toolmakers, gear manufacturers, quality/inspection engineers, and educators involved in the design and production of internal cylindrical gears.

Q: Is it current or superseded?

A: The standard carries the designation -73 (approved 1973) and was introduced 01 January 1975. Public records indicate its limitation of validity was removed and it remains listed as an active GOST (reprints exist, e.g., 1992); users should check the latest national/regional repositories or standards offices for the definitive current status before relying on it for regulatory compliance.

Q: Is it part of a series?

A: Yes — it is part of the family of GOSTs covering gear design and manufacturing. It is typically used alongside other gear standards (external gear calculation, reference contours, tolerances and drawing standards) that together form the design and documentation system for gear transmissions.

Q: What are the key keywords?

A: Internal gear, involute, cylindrical gear, geometry calculation, module, interference, addendum, dedendum, tooth thickness, GOST.