ISO 3545-3:1989

Steel tubes and fittings - Symbols for use in specifications - Part 3: Tubular fittings with circular cross-section

This part defines the most common symbols with the aim of standardizing and facilitating the use of terminology in standards for steel hollow sections and associated products. Five figures illustrate the meaning of the text. Annex A contains the bibliography.

Tubes et raccords en acier — Symboles à utiliser dans les spécifications — Partie 3: Accessoires tubulaires à section circulaire

La présente partie de l'ISO 3545 définit les symboles les plus usuels en vue de faciliter et d'unifier le langage dans le domaine des normes pour accessoires tubulaires en acier susceptibles d'être élaborées.

Jeklene cevi in fitingi - Simboli za rabo v specifikacijah - 3. del: Cevni fitingi s krožnim prerezom

General Information

• Status: Published
• Publication Date: 29-Nov-1989
• ICS: 23.040.40 - Metal fittings
• Technical Committee: ISO/TC 5/SC 1 - Steel tubes
• Drafting Committee: ISO/TC 5/SC 1 - Steel tubes
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 08-Dec-2025
• Completion Date: 13-Dec-2025
• Ref Project: SIST ISO 3545-3:1995 - Steel tubes and fittings -- Symbols for use in specifications -- Part 3: Tubular fittings with circular cross-section

Relations

• Revises: ISO 3545:1981 - Steel tubes and tubular shaped accessories with circular cross-section - Symbols to be used in specifications
• Effective Date: 15-Apr-2008

Overview

ISO 3545-3:1989 is an international standard developed by the International Organization for Standardization (ISO) that focuses on the symbols used in specifications for steel tubular fittings with circular cross-sections. This standard provides a unified set of symbols aimed at standardizing terminology in relation to steel tubes and fittings, specifically those with circular profiles. It helps manufacturers, engineers, and technical professionals accurately communicate dimensions, tolerances, and service conditions related to steel tubular fittings.

The document is part of the broader ISO 3545 series which addresses symbols for steel tubes and fittings in various cross-sections, promoting clarity and consistency across industry documentation and technical standards.

Key Topics

• Standardized Symbols: The standard defines symbols for dimensions including outside and inside diameters, thicknesses adjacent to major and minor diameters, lengths of straight ends, bending radii, nominal sizes, and pressures.
• Symbols for Service Conditions: Includes specification of nominal and service pressures and temperatures, critical for engineering and safety assessments.
• Tolerances and Alignment Symbols: Addresses angular and perpendicular alignment tolerances to ensure accurate engineering and fitting of parts.
• Types of Tubular Fittings Covered: Symbols are provided for common fittings such as:
  • Bends (with detailed bending radii identification)
  • Reducers (both concentric and eccentric)
  • Tees (equal and reducing)
  • Caps
• Illustrative Figures: Five figures accompany the text to visually explain the symbols and their application on tubular fittings.
• Annex A - Bibliography: Provides references to related ISO standards on steel fittings for additional context.

Applications

ISO 3545-3:1989 is essential for industries involved in the design, production, and use of steel tubular fittings, including:

• Oil and Gas: For pipelines and pressure vessel construction requiring clear dimensional specifications and pressure ratings.
• Construction and Civil Engineering: In structural frameworks where steel tubes with circular sections are prevalent.
• Mechanical Engineering: For machinery and equipment involving fluid transport through tubular steel components.
• Manufacturing: Facilitates standardized production drawings and specifications, minimizing errors and misinterpretations.
• Quality Control: Enables consistent inspection protocols based on recognized symbols and tolerances.

Using ISO 3545-3 greatly improves communication between international suppliers, manufacturers, and end-users by ensuring that all parties understand the precise nature of tubular fittings as described in specifications.

Related Standards

• ISO 3545-1: Symbols for steel tubes and fittings - General terms.
• ISO 3545-2: Symbols for steel tubes and fittings - Square and rectangular hollow sections.
• ISO 5252:1977: Steel tubes - Tolerances systems, complementing the tolerance symbols used in ISO 3545-3.
• ISO 3419:1981: Non-alloy and alloy steel butt-welding fittings – relevant for butt-welding joint specifications.
• ISO 5251:1981: Stainless steel butt-welding fittings, related to material-specific applications of fittings.

---

Adopting ISO 3545-3:1989 ensures accurate and universally understood specifications for tubular steel fittings with circular cross-sections, supporting efficient design, manufacture, and quality assurance processes worldwide. This standard is a key reference point in steel tubing industries aiming for high-quality, consistent documentation of tubular fittings.

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-1995
Jeklene cevi in fitingi - Simboli za rabo v specifikacijah - 3. del: Cevni fitingi s
krožnim prerezom
Steel tubes and fittings -- Symbols for use in specifications -- Part 3: Tubular fittings with
circular cross-section
Tubes et raccords en acier -- Symboles à utiliser dans les spécifications -- Partie 3:
Accessoires tubulaires à section circulaire
Ta slovenski standard je istoveten z: ISO 3545-3:1989
ICS:
01.080.30 *UDILþQLVLPEROL]DXSRUDERY Graphical symbols for use on
ULVEDKGLDJUDPLKQDþUWLK mechanical engineering and
]HPOMHYLGLKYVWURMQLãWYXLQ construction drawings,
JUDGEHQLãWYXWHUYXVWUH]QL diagrams, plans, maps and in
WHKQLþQLSURL]YRGQL relevant technical product
GRNXPHQWDFLML documentation
23.040.40 Kovinski fitingi Metal fittings
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

INTERNATIONAL
ISO
STANDARD
3545-3
First edition
1989-12-01
Steel tubes and fittings - Symbols for use in
specifications -
Part 3:
Tubular fittings with circular cross-section
. .
Tubes et raccords en acier - Symboles 2 utiliser dans /es spkifica tions -
Partie 3: Accessoires tubulaires h section circulaire
Reference number
ISO 3545-3 : 1989 (EI
ISO 3545-3 : 1989 (El
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bedies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch 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, govern-
mental 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.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 3545-3 was prepared by Technical Committee ISO/TC 5,
Ferrous metal pipes and metallic fittings.
ISO 3545 consists of the following Parts, under the general title Steel tubes and fittings
- Symbols for use in specifications :
-
Part 7: Tubes and tubular accessories with circular Cross-section
- Part 2: Square and rectangular hollow sections
- Part 3: Tubular fittings with circular Cross-section
Annex A of this part of ISO 3545 is for information only.
0 ISO 1989
All rights reserved. No patt of this publication may be reproduced or utilized in any form or by any
means, electronie or mechan
...

INTERNATIONAL
ISO
STANDARD
3545-3
First edition
1989-12-01
Steel tubes and fittings - Symbols for use in
specifications -
Part 3:
Tubular fittings with circular cross-section
. .
Tubes et raccords en acier - Symboles 2 utiliser dans /es spkifica tions -
Partie 3: Accessoires tubulaires h section circulaire
Reference number
ISO 3545-3 : 1989 (EI
ISO 3545-3 : 1989 (El
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bedies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch 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, govern-
mental 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.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 3545-3 was prepared by Technical Committee ISO/TC 5,
Ferrous metal pipes and metallic fittings.
ISO 3545 consists of the following Parts, under the general title Steel tubes and fittings
- Symbols for use in specifications :
-
Part 7: Tubes and tubular accessories with circular Cross-section
- Part 2: Square and rectangular hollow sections
- Part 3: Tubular fittings with circular Cross-section
Annex A of this part of ISO 3545 is for information only.
0 ISO 1989
All rights reserved. No patt of this publication may be reproduced or utilized in any form or by any
means, electronie or mechanical, including photocopying and microfilm, without Permission in
writing from the publisher.
International Organization for Standardization
Case postale 56 l CH-1211 Geneve 20 e Switzerland
Printed in Switzerland
ISO 3545-3 : 1989 (E)
INTERNATIONAL STANDARD
Steel tubes and fittings - Symbols for use in
specifications -
Part 3 :
Tubular fittings with circular cross-section
T= thickness
1 Scope
F= value of bending radius
This part of ISO 3545 defines the most common Symbols with
the aim of standardizing and facilitating the use of terminology
L= length of straight end
in Standards for tubula
...

ISO
NORME
3545-3
INTERNATIONALE
Première édition
1989-12-01
Tubes et raccords en acier - Symboles à utiliser
dans les spécifications -
Partie 3:
Accessoires tubulaires à section circulaire
Symbols for use in specifications -
Steel tubes and fittings -
Part 3: Tubular fittings with circular cross-section
Numéro de référence
ISO 3545-3 : 1989 (FI
Avant-propos
L’ISO (Organisation internationale de normalisation) est une fédération mondiale
d’organismes nationaux de normalisation (comités membres de I’ISO). L’élaboration
des Normes internationales est en général confiée aux comités techniques de I’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 I’ISO participent également aux travaux. L’ISO col-
labore étroitement avec la Commission électrotechnique internationale (CEI) en ce qui
concerne la normalisation électrotechnique.
Les projets de Normes internationales adoptés par les comités techniques sont soumis
aux comités membres pour approbation, avant leur acceptation comme Normes inter-
nationales par le Conseil de I’ISO. Les Normes internationales sont approuvées confor-
mément aux procédures de I’ISO qui requièrent l’approbation de 75 % au moins des
comités membres votants.
La Norme internationale ISO 3545-3 a été élaborée par le comité technique ISO/TC 5,
Tuyauteries en mhtaux ferreux et raccords métalliques.
L’ISO 3545 comprend les parties suivantes, présentées sous le titre général Tubes et
raccords en acier - Symboles à utiliser dans les spécifications :
-
Partie 1: Tubes et accessoires de forme tubulaire à section circulaire
- Partie 2: Profils creux à section carrée ou rectangulaire
- Partie 3: Accessoires tubulaires à section circulaire
L’annexe A de la présente partie de I’ISO 3545 est donnée uniquement à titre d’infor-
mation.
0 ISO 1989
Droits de reproduction réservés. 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’éditeur.
Organisation internationale de normalisation
Case postale 56 l CH-121 1 Genève 20 l Suisse
Imprimé en Suisse
ISO 3545-3 : 1989 (F)
NORME INTERNATIONALE
Tubes et raccords en acier - Symboles à utiliser
dans les spécifications -
Partie 3 :
Accessoires tubulaires à section circulaire
T= épaisseur
1 Domaine d’application
La présente partie de I’ISO 3545 définit les symboles les plus
F = valeur du rayon de cintrage
usuels en vue de faciliter et d’unifier le langage dans le domaine
des normes pour accessoires tubulaires en acier susceptibles
L= longueur de la partie droite
d’être él
...