GOST 3129-70 PDF

Full title and description

GOST 3129-70 — Taper pins. Construction and dimensions (Russian: Штифты конические незакаленные. Технические условия). National standard specifying design, nominal sizes, tolerances, classes and basic technical requirements for unhardened (conical) taper pins used as fastening and locating elements in mechanical assemblies.

Abstract

This standard defines the construction, nominal dimensions, tolerances, classes of accuracy and marking of unhardened taper (conical) pins. It covers pin geometry (including cone ratio), dimensional series, permissible sizes and mass data for standard metric diameters and lengths, and indicates typical materials and surface finishes used for these fasteners.

General information

• Status: Active (national GOST, maintained in standards catalogues).
• Publication date: Adopted as GOST 3129-70 (designation year 1970); published / came into force 1 July 1971.
• Publisher: State Committee for Standards of the USSR (Gosstandart); current custodian practice under national standards bodies (Rosstandart) for Russian GOST documentation.
• ICS / categories: 21.060.50 — Pins, nails (Fasteners).
• Edition / version: Original GOST 3129-70 (with later amendments recorded, e.g. amendments in 1979, 1984, 1988).
• Number of pages: Approximately 5 pages (standard text and tables).

Scope

Applies to unhardened taper (conical) pins of accuracy classes A and B with nominal diameters from 0.6 mm to 50 mm and nominal lengths per the standard (lengths given by the dimensional series, up to several hundred millimetres). The standard specifies the cone (1:50), dimensional series, end forms (chamfered or radiused), measurement conventions and a table of theoretical masses for standard sizes. It is intended for general mechanical engineering, repair and assembly applications where precise locating or removable fastening is required.

Key topics and requirements

• Definition of pin types and two executions (end chamfer or rounded end) and classes of accuracy (A and B).
• Nominal diameter range: 0.6 mm to 50 mm and corresponding nominal lengths (standard length series specified in the table).
• Cone ratio: 1:50 (geometric taper specification used for manufacture and mating holes).
• Dimensional tolerances and measurement conventions (how diameter and length are defined and measured along the tapered surface).
• Table of theoretical masses for 1 000 pieces by size to support material and weight calculations.
• Typical materials and permissible surface finishes (carbon steels, stainless steels such as A2/A4; coatings including chemical oxide, phosphate with oil, zinc/chromate and other protective finishes as listed).
• References to related dimensional / conformity requirements and notes on interchangeability with common international equivalents (e.g., DIN 1, ISO 2339 series).

Typical use and users

Used by mechanical designers, product engineers, maintenance and repair workshops, fastening suppliers and purchasers. Typical applications include locating and securing mating parts in machine tools, gearboxes, engines, instruments and general machinery where a removable, precise alignment pin is required. Also used by manufacturers of standard fasteners and by procurement departments specifying GOST-compliant parts.

Related standards

International and national documents commonly referenced alongside GOST 3129-70: ISO 2339 (Taper pins — unhardened), DIN 1 (metric taper pin series), related GOSTs for other pin types and threaded taper pins. The standard has been cross-referenced with regional/industry documents (e.g., ST SEV / CMEA listings) and typical fastener classification ICS 21.060.50.

Keywords

GOST 3129-70, taper pin, conical pin, unhardened pin, dowel pin, fastening, 1:50 taper, diameters 0.6–50 mm, accuracy classes A B, mechanical fastening

FAQ

Q: What is this standard?

A: GOST 3129-70 is a Soviet / national standard that specifies construction, dimensions and technical requirements for unhardened taper (conical) pins used as fasteners and locating elements.

Q: What does it cover?

A: It covers nominal diameters and lengths, cone ratio (1:50), accuracy classes (A and B), end forms, measurement conventions and theoretical mass tables, plus guidance on materials and surface finishes for standard taper pins.

Q: Who typically uses it?

A: Mechanical designers, manufacturing engineers, fastener suppliers, maintenance specialists and procurement teams who specify or produce conical (taper) pins for machine assemblies and repairs.

Q: Is it current or superseded?

A: The document is listed in standards catalogues as the national GOST for unhardened taper pins (designation 3129-70). There have been recorded amendments; users should check the current national standards catalogues or the responsible standards body for the latest status or any superseding documents before final specification.

Q: Is it part of a series?

A: It is a standalone GOST for one type of fastener (unhardened taper pins) but is commonly used together with other pin- and fastener-related standards (for example ISO 2339 and various DIN standards) that define alternate series, threaded variants or hardened dowel pins.

Q: What are the key keywords?

A: taper pin, conical pin, GOST 3129-70, unhardened pin, dowel, 1:50 taper, fastener, accuracy class A, accuracy class B