EN ISO 3581:2023

Welding consumables - Covered electrodes for manual metal arc welding of stainless and heat-resisting steels - Classification (ISO 3581:2023)

This document specifies requirements for classification of covered electrodes, based on the all-weld metal chemical composition, the type of electrode covering and other electrode properties, and the all-weld metal mechanical properties, in the as-welded or heat-treated conditions, for manual metal arc welding of stainless and heat-resisting steels.
This document is a combined standard providing for classification utilizing a system based upon classification according to nominal composition or utilizing a system based upon classification according to alloy type.
a)       Paragraphs and tables which carry the label “classification according to nominal composition-A” or “ISO 3581-A” are applicable only to products classified to that system.
b)       Paragraphs and tables which carry the label “classification according to alloy type-B” or “ISO 3581-B” are applicable only to products classified to that system.
c)        Paragraphs and tables which carry neither label are applicable to products classified according to either or both systems.
Annex B gives information on considerations on weld metal ferrite content.

Schweißzusätze - Umhüllte Stabelektroden zum Lichtbogenhandschweißen von nichtrostenden und hitzebeständigen Stählen - Einteilung (ISO 3581:2023)

Dieses Dokument legt Anforderungen an die Einteilung von umhüllten Stabelektroden basierend auf der chemischen Zusammensetzung des reinen Schweißgutes, dem Umhüllungstyp und anderen Elektrodeneigenschaften sowie die mechanischen Eigenschaften des reinen Schweißgutes, im Schweißzustand oder nach Wärmebehandlung, für das Lichtbogenhandschweißen von nichtrostenden und hitzebeständigen Stählen fest.
Dieses Dokument ist eine kombinierte Einteilungsnorm und benutzt zur Einteilung ein System auf Grundlage der Nennzusammensetzung oder ein System auf Grundlage des Legierungstyps.
a)   Abschnitte und Tabellen mit der Bezeichnung „Einteilung nach der Nennzusammensetzung-A“ oder „ISO 3581-A“ sind nur für solche Produkte anwendbar, die nach diesem System eingeteilt sind.
b)   Abschnitte und Tabellen mit der Bezeichnung „Einteilung nach dem Legierungstyp-B“ oder „ISO 3581-B“ sind nur für solche Produkte anwendbar, die nach diesem System eingeteilt sind.
c)   Abschnitte und Tabellen, die keine dieser Bezeichnungen enthalten, sind für Produkte eines der beiden oder beider Systeme anwendbar.
Anhang B enthält Informationen über Überlegungen zum Ferritgehalt des Schweißguts.

Produits consommables pour le soudage - Électrodes enrobées pour le soudage manuel à l'arc des aciers inoxydables et résistant aux températures élevées - Classification (ISO 3581:2023)

Le présent document spécifie les exigences relatives à la classification des électrodes enrobées destinées au soudage manuel à l'arc des aciers inoxydables et résistant aux températures élevées, basée sur la composition chimique du métal fondu hors dilution, sur le type d'enrobage d'électrode et d'autres propriétés de l'électrode, ainsi que sur les propriétés mécaniques du métal fondu hors dilution, à l'état brut de soudage ou traité thermiquement.
Le présent document est une norme mixte qui permet une classification utilisant un système basé sur la classification d'après la composition nominale ou utilisant un système basé sur la classification d'après le type d'alliage.
a)       Les paragraphes et les tableaux qui portent la mention «classification d'après la composition nominale-A» ou «ISO 3581-A» ne sont applicables qu'aux produits classifiés d'après ledit système.
b)       Les paragraphes et les tableaux qui portent la mention «classification d'après le type d'alliage-B» ou «ISO 3581-B» ne sont applicables qu'aux produits classifiés d'après ledit système.
c)        Les paragraphes et les tableaux qui ne portent aucune des deux mentions sont applicables aux produits classifiés soit d'après l'un des systèmes, soit d'après les deux systèmes.
L'Annexe B donne des informations sur les considérations sur la teneur de ferrite dans le métal fondu.

Dodajni in pomožni materiali za varjenje - Oplaščene elektrode za ročno obločno varjenje nerjavnih in toplotno odpornih jekel - Razvrstitev (ISO 3581:2023)

Standard ISO 3581:2016 določa zahteve za klasifikacijo oplaščenih elektrod na osnovi kemijske sestave čistega vara, vrste obloge elektrode in drugih značilnosti elektrod ter mehanskih lastnosti čistega vara v varjenem stanju in s toplotno obdelavo za ročno obločno varjenje nerjavnega in toplotno odpornega jekla.
Je kombiniran standard, ki omogoča klasifikacijo z uporabo sistema na osnovi nominalne sestave ali sistema na osnovi klasifikacije glede na vrsto zlitine.
a) Odstavki in preglednice z oznako »razvrstitev v skladu z nominalno sestavo« ali ISO 3581-A se uporabljajo samo za proizvode, razvrščene po tem sistemu.
b) Odstavki in preglednice z oznako »razvrstitev v skladu z vrsto zlitine« ali ISO 3581-B se uporabljajo samo za proizvode, razvrščene po tem sistemu.
c) Odstavki in preglednice brez katere koli od teh oznak se uporabljajo za proizvode, razvrščene v skladu z enim od teh sistemov ali obema sistemoma.

General Information

• Status: Published
• Publication Date: 15-Aug-2023
• ICS: 25.160.20 - Welding consumables
• Technical Committee: CEN/TC 121 - Welding
• Drafting Committee: CEN/TC 121/WG 3 - Welding consumables
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 16-Aug-2023
• Completion Date: 16-Aug-2023
• Ref Project: SIST EN ISO 3581:2023 - Welding consumables - Covered electrodes for manual metal arc welding of stainless and heat-resisting steels - Classification (ISO 3581:2023)

Relations

• Replaces: EN ISO 3581:2016 - Welding consumables - Covered electrodes for manual metal arc welding of stainless and heat-resisting steels - Classification (ISO 3581:2016, Corrected version 2017-11-01)
• Effective Date: 23-Aug-2023

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2023
Nadomešča:
SIST EN ISO 3581:2016
Dodajni in pomožni materiali za varjenje - Oplaščene elektrode za ročno obločno
varjenje nerjavnih in toplotno odpornih jekel - Razvrstitev (ISO 3581:2023)
Welding consumables - Covered electrodes for manual metal arc welding of stainless
and heat-resisting steels - Classification (ISO 3581:2023)
Schweißzusätze - Umhüllte Stabelektroden zum Lichtbogenhandschweißen von
nichtrostenden und hitzebeständigen Stählen - Einteilung (ISO 3581:2023)
Produits consommables pour le soudage - Électrodes enrobées pour le soudage manuel
à l'arc des aciers inoxydables et résistant aux températures élevées - Classification (ISO
3581:2023)
Ta slovenski standard je istoveten z: EN ISO 3581:2023
ICS:
25.160.20 Potrošni material pri varjenju Welding consumables
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 3581
EUROPEAN STANDARD
NORME EUROPÉENNE
August 2023
EUROPÄISCHE NORM
ICS 25.160.20
English Version
Welding consumables - Covered electrodes for manual
metal arc welding of stainless and heat-resisting steels -
Classification (ISO 3581:2023)
Produits consommables pour le soudage - Électrodes Schweißzusätze - Umhüllte Stabelektroden zum
enrobées pour le soudage manuel à l'arc des aciers Lichtbogenhandschweißen von nichtrostenden und
inoxydables et résistant aux températures élevées - hitzebeständigen Stählen - Einteilung (ISO 3581:2023)
Classification (ISO 3581:2023)
This European Standard was approved by CEN on 13 August 2022.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 3581:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 3581:2023) has been prepared by Technical Committee ISO/TC 44 "Welding
and allied processes" in collaboration with Technical Committee CEN/TC 121 “Welding and allied
processes” the secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by February 2024, and conflicting national standards
shall be withdrawn at the latest by February 2024.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 3581:2023 has been approved by CEN as EN ISO 3581:2023 without any modification.

INTERNATIONAL ISO
STANDARD 3581
Fourth edition
2023-08
Welding consumables — Covered
electrodes for manual metal arc
welding of stainless and heat-resisting
steels — Classification
Produits consommables pour le soudage — Électrodes enrobées pour
le soudage manuel à l'arc des aciers inoxydables et résistant aux
températures élevées — Classification
Reference number
ISO 3581:2023(E)
ISO 3581:2023(E)
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
ISO 3581:2023(E)
Contents Page
Foreword .iv
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Classification . 2
4.1 General . 2
4.2 Classification systems . 4
4.2.1 General . 4
4.2.2 Classification: nominal composition — A . 5
4.2.3 Classification: alloy type — B . 5
5 Symbols and requirements . 5
5.1 Symbol for the product or process . 5
5.1.1 Classification according to nominal composition — A . 5
5.1.2 Classification according to alloy type — B . 5
5.1.3 Symbol for the chemical composition of all-weld metal . 5
5.2 Symbol for type of electrode covering . 6
5.2.1 General . 6
5.2.2 Classification according to nominal composition — A . 6
5.2.3 Classification according to alloy type — B . 6
5.3 Symbol for nominal electrode efficiency and type of current . 18
5.3.1 Classification according to nominal composition — A . 18
5.3.2 Classification according to alloy type — B . 18
5.4 Symbol for welding position . 19
6 Chemical analysis . .19
7 Mechanical property tests .19
7.1 General . 19
7.2 Preheat and interpass temperatures . 19
7.3 Pass sequence . 20
8 Fillet weld test .20
9 Rounding procedure .21
10 Retests .21
11 Technical delivery conditions .22
12 Examples of designation .22
12.1 General .22
12.2 Example 1: classification according to nominal composition — A .22
12.3 Example 2: classification according to alloy type — B . 22
12.4 Example 3: Z classification . 23
Annex A (informative) Types of covering .24
Annex B (informative) Considerations on weld metal ferrite contents .26
Bibliography .29
iii
ISO 3581:2023(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each 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, governmental 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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use
of (a) patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed
patent rights in respect thereof. As of the date of publication of this document, ISO had not received
notice of (a) patent(s) which may be required to implement this document. However, implementers are
cautioned that this may not represent the latest information, which may be obtained from the patent
database available at www.iso.org/patents. ISO shall not be held responsible for identifying any or all
such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 44, Welding and allied processes,
Subcommittee SC 3, Welding consumables, in collaboration with the European Committee for
Standardization (CEN) Technical Committee CEN/TC 121, Welding and allied processes, in accordance
with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This fourth edition cancels and replaces the third edition (ISO 3581:2016), which has been technically
revised.
The main changes are as follows:
— the document has been updated in accordance with the drafting guidelines laid out in the ISO House
Style;
— the dates of normative references have been updated to show their latest editions;
— a new Clause 3 (Terms and definitions) has been added in accordance with the standard structure
of ISO documents;
— “weld metal recovery” now reads “nominal electrode efficiency” throughout, in accordance with
ISO 2401;
— a new Table 2 has been added listing classification systems;
— new alloys have been added to Table 3 (formerly Table 2) and associated clauses of the document;
— the chemical compositions of several alloys have been updated in Table 3 (formerly Table 2);
— certain alloys have been reclassified in Table 3 (formerly Table 2);
— a new footnote was added to Table 3 (formerly Table 2) regarding Co content;
iv
ISO 3581:2023(E)
— the wording of Clause 9 (formerly Clause 8) has been updated.
Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html. Official
interpretations of ISO/TC 44 documents, where they exist, are available from this page:
https://committee.iso.org/sites/tc44/home/interpretation.html.
v
ISO 3581:2023(E)
Introduction
This document provides a classification system for covered electrodes for manual metal arc welding of
stainless and heat-resisting steels in terms of chemical composition of deposited weld metal and type of
electrode covering. Other properties of the electrodes are specified by reference to tables.
This document recognizes that there are two somewhat different approaches in the global market for
classifying a given covered electrode for arc welding of stainless steel. It allows for either or both to
be used to suit a particular need. Application of either (or both) type(s) of classification designation
identifies a product as classified according to this document. It is important to note that the two
systems are not exactly equivalent; therefore, each system is to be used independently of the other,
without combining designators in any way.
The classification according to nominal composition (system A) is mainly based on EN 1600. The
classification according to alloy type (system B) is mainly based on standards used around the Pacific
Rim.
vi
INTERNATIONAL STANDARD ISO 3581:2023(E)
Welding consumables — Covered electrodes for manual
metal arc welding of stainless and heat-resisting steels —
Classification
1 Scope
This document specifies requirements for classification of covered electrodes, based on the all-weld
metal chemical composition, the type of electrode covering and other electrode properties, and the all-
weld metal mechanical properties, in the as-welded or heat-treated conditions, for manual metal arc
welding of stainless and heat-resisting steels.
This document is a combined standard providing for classification utilizing a system based upon
classification according to nominal composition or utilizing a system based upon classification
according to alloy type.
a) Paragraphs and tables which carry the label “classification according to nominal composition-A” or
“ISO 3581-A” are applicable only to products classified to that system.
b) Paragraphs and tables which carry the label “classification according to alloy type-B” or “ISO 3581-
B” are applicable only to products classified to that system.
c) Paragraphs and tables which carry neither label are applicable to products classified according to
either or both systems.
Annex B gives information on considerations on weld metal ferrite content.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 544, Welding consumables — Technical delivery conditions for filler materials and fluxes — Type of
product, dimensions, tolerances and markings
ISO 6847, Welding consumables — Deposition of a weld metal pad for chemical analysis
ISO 14344, Welding consumables — Procurement of filler materials and fluxes
ISO 15792-1:2020, Welding consumables — Test methods — Part 1: Preparation of all-weld metal test
pieces and specimens in steel, nickel and nickel alloys
ISO 15792-3, Welding consumables — Test methods — Part 3: Classification testing of positional capacity
and root penetration of welding consumables in a fillet weld
ISO 80000-1:2022, Quantities and units — Part 1: General
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
ISO 3581:2023(E)
— IEC Electropedia: available at https:// www .electropedia .org/
4 Classification
4.1 General
Classification designations are based upon two approaches for indicating the chemical composition of
the all-weld metal deposit obtained with a given electrode.
The “nominal composition ISO 3581-A” approach uses designation components directly indicating the
nominal levels of certain alloying elements, given in a particular order, and some symbols for low but
significant levels of other elements, whose levels are not conveniently expressed as integers.
The “alloy type ISO 3581-B” approach uses tradition-based three-digit or four-digit designations for
alloy families, and occasionally an additional character or characters for compositional modifications
of each original alloy within the family.
Both designation approaches include additional designators for some other classification requirements,
but not entirely the same classification requirements, as explained in the following clauses.
Table 1 lists the tests required for classification of an electrode under each approach.
In many cases, a given commercial product can be classified using both approaches. Then, either or
both classification designations can be used for the product.
Table 1 — Summary of test requirements
b
Position of welding
a
Size
Electrode designation
Chemical analysis All-weld metal
Fillet weld test
mm
test tension test
ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B
2,5 (or 2,4 Not Not Not Not Not
PA
or 2,6) required required required required required
Not Not Not Not
Coating
3,2 or 3,0 PA PA
Position
required required required required
type sym-
and coat-
bol B and Not
ing type 4,0 PA PA PA PA PB, PF, PD
position required
symbol
symbols 1
Not Not Not Not
− 15
5,0 or 4,8 PA PB
and 2
required required required required
6,0 (or 5,6 Not Not Not Not
PA PB
or 6,4) required required required required
a
If the size is not manufactured, the next nearest size may be substituted (provided that the substituted size is different
from that specified in this table).
b
The abbreviations PA, PB, PD, PF and PG indicate welding positions in accordance with ISO 6947:2019:
PA  flat
PB  horizontal vertical
PD  horizontal overhead
PF  vertical up
PG  vertical down
ISO 3581:2023(E)
TTabablele 1 1 ((ccoonnttiinnueuedd))
b
Position of welding
a
Size
Electrode designation
Chemical analysis All-weld metal
mm Fillet weld test
test tension test
ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B
Not Not
3,2 or 3,0 PA
required required
All coating
types and Not Not Not Not Not
4,0 PA PA
position applicable applicable applicable required applicable
symbol 3
Not Not Not
5,0 or 4,8
required required required
2,5 (or 2,4 Not Not Not Not
PA PG
or 2,6) required required required required
Position
Not Not Not
All coating
3,2 or 3,0 PA PA PG
symbol
required required required
types and
− 4 and all
position
Not
coating
4,0 PA PA PA PA PG
symbol 4
required
types
Not Not Not Not
5,0 or 4,8 PA PG
required required required required
Not Not
3,2 (or 3,0) PA
required required
All coating
types and Not Not Not Not Not
4,0 PA PA
position applicable applicable applicable required applicable
symbol 5
Not Not Not
5,0 (or 4,8)
required required required
2,5 (or 2,4 Not Not Not Not Not
PA
or 2,6) required required required required required
Not Not Not Not
Coating Position
3,2 (or 3,0) PA PA
required required required required
type sym- and coat-
bol R and ing type Not
4,0 PA PA PA PA PB, PF, PD
position symbols required
symbols 1 − 16 and −
Not Not Not Not
5,0 (or 4,8) PA PB
and 2 − 17
required required required required
6,0 (or 5,6 Not Not Not Not
PA PB
or 6,4) required required required required
a
If the size is not manufactured, the next nearest size may be substituted (provided that the substituted size is different
from that specified in this table).
b
The abbreviations PA, PB, PD, PF and PG indicate welding positions in accordance with ISO 6947:2019:
PA  flat
PB  horizontal vertical
PD  horizontal overhead
PF  vertical up
PG  vertical down
ISO 3581:2023(E)
TTabablele 1 1 ((ccoonnttiinnueuedd))
b
Position of welding
a
Size
Electrode designation
Chemical analysis All-weld metal
mm Fillet weld test
test tension test
ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B ISO 3581-A ISO 3581-B
2,5 (or 2,4 Not Not
PA
or 2,6) required required
Position
Not Not
3,2 (or 3,0) PA
and coat-
required required
Not ing type Not Not Not
4,0 PA PA PB
applicable symbols applicable applicable applicable
Not
− 26 and
5,0 (or 4,8) PA PB
required
− 27
6,0 (or 5,6 Not
PA PB
or 6,4) required
a
If the size is not manufactured, the next nearest size may be substituted (provided that the substituted size is different
from that specified in this table).
b
The abbreviations PA, PB, PD, PF and PG indicate welding positions in accordance with ISO 6947:2019:
PA  flat
PB  horizontal vertical
PD  horizontal overhead
PF  vertical up
PG  vertical down
4.2 Classification systems
4.2.1 General
Table 2 gives the requirements for classification according to:
— nominal composition — ISO 3581-A; and
— alloy type — ISO 3581-B.
NOTE The composition of the core wire, which can be substantially different from the weld metal
composition, is not considered a classification criterion.
Table 2 — Classification systems
Classification according to:
Nominal composition — ISO 3581-A Alloy type — ISO 3581-B
The classification is divided into five parts: The classification is divided into four parts:
1) a symbol indicating the product or pro- 1) a symbol indicating the product or pro-
cess to be identified (see 5.1) cess to be identified (see 5.1)
2) a symbol indicating the chemical compo- 2) a symbol indicating the chemical compo-
sition of all-weld metal (see Table 3) sition of all-weld metal (see Table 3)
3) a symbol indicating the type of electrode 3) a symbol indicating the welding position
covering (see 5.3) (see Table 6)
4) a symbol indicating the nominal elec- 4) a symbol indicating the type of electrode
trode efficiency, R , and type of current (see covering. This also serves to specify the
N
Table 5) type of current which can be used with the
electrode classified (see 5.2.3)
5) a symbol indicating the welding position
(see Table 6)
ISO 3581:2023(E)
4.2.2 Classification: nominal composition — A
This classification includes all-weld metal properties obtained with a covered electrode as follows.
The classification is based on an electrode diameter of 4 mm, with the exception of testing for welding
position. When 4-mm-diameter electrodes are not manufactured, the next closest diameter shall be
tested.
Classification according to nominal composition is split into two sections.
— Compulsory section: includes the symbols for the type of product, the chemical composition, and
the type of covering, i.e. symbols in accordance with 5.1 and 5.2.
— Optional section: includes the symbols for the nominal electrode efficiency, R , (see ISO 2401) the
N
type of current, and the welding positions for which the electrode is suitable, i.e. the symbols in
accordance with 5.4 and Table 5.
The full designation (compulsory and optional sections, as applicable) shall be used on packages and in
the manufacturer's literature and data sheets.
4.2.3 Classification: alloy type — B
This classification includes all-weld metal properties obtained with a covered electrode as follows. The
classification is based on an electrode diameter of 4 mm for mechanical properties, with the exception
of testing for welding position and for chemical analysis of the weld metal. When 4-mm-diameter
electrodes are not manufactured, the next closest diameter shall be tested. In classifying welding
electrodes according to alloy type, the symbols for all four parts (product or process, alloy type, welding
position and type of electrode covering) in accordance with 5.1, 5.2 and 5.4 are compulsory.
The full designation shall be used on packages and in the manufacturer's literature and data sheets.
5 Symbols and requirements
5.1 Symbol for the product or process
5.1.1 Classification according to nominal composition — A
The symbol for a covered electrode using the manual metal arc welding process for stainless and heat-
resisting steels in accordance with ISO 3581-A shall be the letter E.
5.1.2 Classification according to alloy type — B
The symbol for a covered electrode using the manual metal arc welding process for stainless and heat-
resisting steels in accordance with ISO 3581-B shall be the letters ES. The initial letter “E” indicates a
covered electrode while the letter “S” indicates stainless and heat-resisting steels.
5.1.3 Symbol for the chemical composition of all-weld metal
The symbols in Table 3 indicate the chemical composition of all-weld metal determined in accordance
with Clause 6. The all-weld metal obtained with the covered electrodes in Table 3, in accordance with
Clause 7, shall also fulfil the mechanical property requirements for that electrode as specified in Table 4.
A symbol classification in parentheses indicates a near match in the other designation system, but not
an exact match. The correct designation for a given composition is the one without parentheses. A given
product may, by having a more restricted chemical composition that fulfils both sets of requirements,
be assigned both designations independently, provided that the mechanical property requirements are
met.
ISO 3581:2023(E)
5.2 Symbol for type of electrode covering
5.2.1 General
The type of electrode covering determines, to a large extent, usability characteristics of the electrode
and properties of the weld metal. See Annex A for information on coating types.
5.2.2 Classification according to nominal composition — A
The following two symbols are used to describe the type of covering:
— B denotes a basic covering;
— R denotes a rutile-based covering.
5.2.3 Classification according to alloy type — B
The following three symbols are used to specify the type of covering on the electrode:
— 5 denotes a basic covering intended for DC welding;
— 6 denotes a rutile-based coating intended for DC or AC welding (except that position and coating
type −46 is DC);
— 7 denotes a modified rutile-based coating containing a considerable amount of silica, intended for
DC or AC welding (except that position and coating type −47 is DC).
ISO 3581:2023(E)
Table 3 — Chemical composition requirements
a,b,c
Chemical composition
Symbol classification by:
% (by mass)
Nominal Other
e
composition Alloy type speci-
C Si Mn P S Cr Ni Mo Cu Nb + Ta N
d,e
(ISO 3581-B) fied ele-
f
(ISO 3581-A) ments
Martensitic and ferritic types
11,0 to 0,50 to
— 409Nb 0,12 1,0 1,00 0,04 0,03 0,6 0,75 0,75 — —
14,0 1,50
11,0 to
e
13 (410) 0,12 1,0 1,5 0,030 0,025 0,60 0,75 0,75 — — —
14,0
11,0 to
e
(13) 410 0,12 0,90 1,0 0,04 0,03 0,7 0,75 0,75 — — —
14,0
11,0 to
e
13 4 (410NiMo) 0,06 1,0 1,5 0,030 0,025 3,0 to 5,0 0,4 to 1,0 0,75 — — —
14,5
11,0 to 0,40 to
e
(13 4) 410NiMo 0,06 0,90 1,0 0,04 0,03 4,0 to 5,0 0,75 — — —
12,5 0,70
16,0 to
e
17 (430) 0,12 1,0 1,5 0,030 0,025 0,60 0,75 0,75 — — —
18,0
15,0 to
e
(17) 430 0,10 0,90 1,0 0,04 0,03 0,6 0,75 0,75 — — —
18,0
15,0 to 0,50 to
— 430Nb 0,10 1,0 1,00 0,04 0,03 0,6 0,75 0,75 — —
18,0 1,50
Austenitic types
20,5 to 0,10 to V 0,10 to
— 209 0,06 1,00 4,0 to 7,0 0,04 0,03 9,5 to 12,0 1,5 to 3,0 0,75 —
24,0 0,30 0,30
19,0 to 0,10 to
— 219 0,06 1,00 8,0 to 10,0 0,04 0,03 5,5 to 7,0 0,75 0,75 — —
21,5 0,30
10,5 to 17,0 to 0,10 to
— 240 0,06 1,00 0,04 0,03 4,0 to 6,0 0,75 0,75 — —
13,5 19,0 0,30
18,0 to
e
19 9 (308) 0,08 1,2 2,0 0,030 0,025 9,0 to 11,0 0,75 0,75 — — —
21,0
18,0 to
e
(19 9) 308 0,08 1,00 0,5 to 2,5 0,04 0,03 9,0 to 11,0 0,75 0,75 — — —
21,0
ISO 3581:2023(E)
Table 3 (continued)
a,b,c
Chemical composition
Symbol classification by:
% (by mass)
Nominal Other
e
composition Alloy type speci-
C Si Mn P S Cr Ni Mo Cu Nb + Ta N
d,e
(ISO 3581-B) fied ele-
f
(ISO 3581-A) ments
0,04 to 18,0 to
e
19 9 H (308H) 1,2 2,0 0,03 0,025 9,0 to 11,0 0,75 0,75 — — —
0,08 21,0
0,04 to 18,0 to
e
(19 9 H) 308H 1,00 0,5 to 2,5 0,04 0,03 9,0 to 11,0 0,75 0,75 — — —
0,08 21,0
18,0 to
e
19 9 L (308L) 0,04 1,2 2,0 0,030 0,025 9,0 to 11,0 0,75 0,75 — — —
21,0
18,0 to
e
(19 9 L) 308L 0,04 1,00 0,5 to 2,5 0,04 0,03 9,0 to 11,0 0,75 0,75 — — —
21,0
18,00 to 9,00 to 0,06 to
19 9 N L 308LN 0,035 0,90 0,5 to 2,0 0,025 0,025 0,50 0,75 — —
21,00 11,00 0,10
18,0 to
e
(20 10 3) 308Mo 0,08 1,00 0,5 to 2,5 0,04 0,03 9,0 to 12,0 2,0 to 3,0 0,75 — — —
21,0
18,0 to
— 308LMo 0,04 1,00 0,5 to 2,5 0,04 0,03 9,0 to 12,0 2,0 to 3,0 0,75 — — —
21,0
21,0 to 0,12 to
— 308N 0,10 0,90 1,0 to 4,0 0,04 0,03 7,0 to 10,0 — — — —
25,0 0,30
V 0,10 to
0,30
18,0 to 0,35 to 0,75 to
— 349 0,13 1,00 0,5 to 2,5 0,04 0,03 8,0 to 10,0 0,75 — Ti 0,15
21,0 0,65 1,20
W 1,25
to 1,75
18,0 to 8 × C to
e
19 9 Nb (347) 0,08 1,2 2,0 0,030 0,025 9,0 to 11,0 0,75 0,75 — —
21,0 1,1
18,0 to 8 × C to
e
(19 9 Nb) 347 0,08 1,00 0,5 to 2,5 0,04 0,03 9,0 to 11,0 0,75 0,75 — —
21,0 1,00
18,0 to 8 × C to
— 347L 0,04 1,00 0,5 to 2,5 0,040 0,030 9,0 to 11,0 0,75 0,75 — —
21,0 1,00
17,0 to 10,0 to
e
19 12 2 (316) 0,08 1,2 2,0 0,030 0,025 2,0 to 3,0 0,75 — — —
20,0 13,0
ISO 3581:2023(E)
Table 3 (continued)
a,b,c
Chemical composition
Symbol classification by:
% (by mass)
Nominal Other
e
composition Alloy type speci-
C Si Mn P S Cr Ni Mo Cu Nb + Ta N
d,e
(ISO 3581-B) fied ele-
f
(ISO 3581-A) ments
17,0 to 11,0 to
e
(19 12 2) 316 0,08 1,00 0,5 to 2,5 0,04 0,03 2,0 to 3,0 0,75 — — —
20,0 14,0
0,04 to 17,0 to 11,0 to
e
(19 12 2) 316H 1,00 0,5 to 2,5 0,04 0,03 2,0 to 3,0 0,75 — — —
0,08 20,0 14,0
17,0 to 11,0 to
e
(19 12 3 L) 316L 0,04 1,00 0,5 to 2,5 0,04 0,03 2,0 to 3,0 0,75 — — —
20,0 14,0
17,0 to 10,0 to
e
19 12 3 L (316L) 0,04 1,2 2,0 0,030 0,025 2,5 to 3,0 0,75 — — —
20,0 13,0
18,0 to 12,0 to 0,06 to
19 12 3 N L 316LN 0,035 0,90 0,5 to 2,0 0,025 0,025 2,5 to 3,0 0,75 — Co 0,20
20,0 13,0 0,10
17,0 to 11,0 to 1,20 to 1,00 to
— 316LCu 0,04 1,00 0,5 to 2,5 0,040 0,030 — — —
20,0 16,0 2,75 2,50
18,0 to 15,0 to 0,10 to
— 316LMn 0,04 0,90 5,0 to 8,0 0,04 0,03 2,5 to 3,5 0,75 — —
21,0 18,0 0,25
18,0 to 12,0 to
— 317 0,08 1,00 0,5 to 2,5 0,04 0,03 3,0 to 4,0 0,75 — — —
21,0 14,0
18,0 to 12,0 to
— 317L 0,04 1,00 0,5 to 2,5 0,04 0,03 3,0 to 4,0 0,75 — — —
21,0 14,0
17,0 to 10,0 to 8 × C to
e
19 12 3 Nb (318) 0,08 1,2 2,0 0,030 0,025 2,5 to 3,0 0,75 — —
20,0 13,0 1,1
17,0 to 11,0 to 6 × C to
e
(19 12 3 Nb) 318 0,08 1,00 0,5 to 2,5 0,04 0,03 2,0 to 3,0 0,75 — —
20,0 14,0 1,00
17,0 to 12,0 to
19 13 4 N L — 0,04 1,2 1,0 to 5,0 0,030 0,025 3,0 to 4,5 0,75 — 0,20 —
20,0 15,0
19,0 to 32,0 to 8 × C to
— 320 0,07 0,60 0,5 to 2,5 0,04 0,03 2,0 to 3,0 3,0 to 4,0 — —
21,0 36,0 1,00
1,50 to 19,0 to 32,0 to 8 × C to
— 320LR 0,03 0,30 0,020 0,015 2,0 to 3,0 3,0 to 4,0 — —
2,50 21,0 36,0 0,40
ISO 3581:2023(E)
Table 3 (continued)
a,b,c
Chemical composition
Symbol classification by:
% (by mass)
Nominal Other
e
composition Alloy type speci-
C Si Mn P S Cr Ni Mo Cu Nb + Ta N
d,e
(ISO 3581-B) fied ele-
f
(ISO 3581-A) ments
Ferritic-austenitic types, sometimes referred to as austenitic-ferritic types
21,0 to 0,08 to
e
22 9 3 N L (2209) 0,04 1,2 2,5 0,030 0,025 7,5 to 10,5 2,5 to 4,0 0,75 — —
24,0 0,20
21,5 to 0,08 to
e
(22 9 3 N L) 2209 0,04 1,00 0,5 to 2,0 0,04 0,03 8,5 to 10,5 2,5 to 3,5 0,75 — —
23,5 0,20
22,5 to 0,10 to
23 7 N L 2307 0,04 1,0 0,4 to 1,5 0,030 0,020 6,5 to 10,0 0,8 0,50 — —
25,5 0,20
24,0 to
d
25 7 2 N L — 0,04 1,2 2,0 0,035 0,025 6,0 to 8,0 1,0 to 3,0 0,75 — 0,20 —
28,0
24,0 to 0,10 to
e
25 9 3 Cu N L (2593) 0,04 1,2 2,5 0,030 0,025 7,5 to 10,5 2,5 to 4,0 1,5 to 3,5 — —
27,0 0,25
(25 9 3 Cu N 24,0 to 0,08 to
2593 0,04 1,00 0,5 to 1,5 0,04 0,03 8,5 to 10,5 2,9 to 3,9 1,5 to 3,0 — —
e
L) 27,0 0,25
24,0 to 0,20 to
d e
25 9 4 N L (2595) 0,04 1,2 2,5 0,030 0,025 8,0 to 11,0 2,5 to 4,5 1,5 — W 1,0
27,0 0,30
24,0 to 0,20 to W 0,4 to
e
(25 9 4 N L) 2595 0,04 1,2 2,5 0,03 0,025 8,0 to 10,5 2,5 to 4,5 0,4 to 1,5 —
27,0 0,30 1,0
24,0 to 0,20 to
— 2594 0,04 1,00 0,5 to 2,0 0,04 0,03 8,0 to 10,5 3,5 to 4,5 0,75 — —
27,0 0,30
23,0 to 0,08 to
25 9 4 W N L 2594W 0,04 1,0 0,5 to 2,5 0,04 0,03 8,0 to 11,0 3,0 to 4,5 1,0 — W 2,5
27,0 0,30
24,0 to 0,10 to
— 2553 0,06 1,00 0,5 to 1,5 0,04 0,03 6,5 to 8,5 2,9 to 3,9 1,5 to 2,5 — —
27,0 0,25
Fully austenitic types
31,0 to 30,0 to
— 33-31 0,03 0,9 2,5 to 4,0 0,02 0,01 1,0 to 2,0 0,4 to 0,8 — 0,3 to 0,5 —
35,0 32,0
26,5 to 30,0 to
— 383 0,03 0,90 0,5 to 2,5 0,02 0,02 3,2 to 4,2 0,6 to 1,5 — — —
29,0 33,0
ISO 3581:2023(E)
Table 3 (continued)
a,b,c
Chemical composition
Symbol classification by:
% (by mass)
Nominal Other
e
composition Alloy type speci-
C Si Mn P S Cr Ni Mo Cu Nb + Ta N
d,e
(ISO 3581-B) fied ele-
f
(ISO 3581-A) ments
(20 25 5 Cu N 19,5 to 24,0 to
385 0,03 0,90 1,0 to 2,5 0,03 0,02 4,2 to 5,2 1,2 to 2,0 — — —
e
L) 21,5 26,0
16,5 to 14,0 to
18 15 3 L — 0,04 1,2 1,0 to 4,0 0,030 0,025 2,5 to 3,5 0,75 — — —
19,5 17,0
17,0 to 15,5 to
d
18 16 5 N L — 0,04 1,2 1,0 to 4,0 0,035 0,025 3,5 to 5,0 0,75 — 0,20 —
20,0 19,0
19,0 to 24,0 to
e
20 25 5 Cu N L (385) 0,04 1,2 1,0 to 4,0 0,030 0,025 4,0 to 7,0 1,0 to 2,0 — 0,25 —
22,0 27,0
20 16 3 Mn N 18,0 to 15,0 to
— 0,04 1,2 5,0 to 8,0 0,035 0,025 2,5 to 3,5 0,75 — 0,20 —
d
L 21,0 18,0
24,0 to 20,0 to
25 22 2 N L — 0,04 1,2 1,0 to 5,0 0,030 0,025 2,0 to 3,0 0,75 — 0,20 —
27,0 23,0
26,0 to 30,0 to
27 31 4 Cu L — 0,04 1,2 2,5 0,030 0,025 3,0 to 4,5 0,6 to 1,5 — — —
29,0 33,0
Co 18,5
to 21,0
20,0 to 19,0 to 0,75 to
— 3155 0,10 1,00 1,0 to 2,5 0,04 0,03 2,5 to 3,5 0,75 —
22,5 21,0 1,25
W 2,0 to
3,0
Special types, often used for dissimilar metal joining
17,0 to
d
18 8 Mn — 0,20 1,2 4,5 to 7,5 0,035 0,025 7,0 to 10,0 0,75 0,75 — — —
20,0
0,04 to 18,0 to
d e
18 9 Mn Mo (307) 1,2 3,0 to 5,0 0,035 0,025 9,0 to 11,0 0,5 to 1,5 0,75 — — —
0,14 21,5
0,04 to 3,30 to 18,0 to
e
(18 9 Mn Mo) 307 1,00 0,04 0,03 9,0 to 10,7 0,5 to 1,5 0,75 — — —
0,14 4,75 21,5
18,0 to
e
20 10 3 (308Mo) 0,10 1,2 2,5 0,030 0,025 9,0 to 12,0 1,5 to 3,5 0,75 — — —
21,0
20,0 to 10,0 to
e
22 12 (309) 0,15 1,2 2,5 0,030 0,025 0,75 0,75 — — —
23,0 13,0
ISO 3581:2023(E)
Table 3 (continued)
a,b,c
Chemical composition
Symbol classification by:
% (by mass)
Nominal Other
e
composition Alloy type speci-
C Si Mn P S Cr Ni Mo Cu Nb + Ta N
d,e
(ISO 3581-B) fied ele-
f
(ISO 3581-A) ments
22,0 to 12,0 to
e
(22 12) 309 0,15 1,00 0,5 to 2,5 0,04 0,03 0,75 0,75 — — —
25,0 14,0
22,0 to 11,0 to
e
23 12 L (309L) 0,04 1,2 2,5 0,030 0,025 0,75 0,75 — — —
25,0 14,0
22,0 to 12,0 to
e
(23 12 L) 309L 0,04 1,00 0,5 to 2,5 0,04 0,03 0,75 0,75 — — —
25,0 14,0
22,0 to 11,0 to 8 × C to
e
23 12 Nb (309Nb) 0,10 1,2 2,5 0,030 0,025 0,75 0,75 — —
25,0 14,0 1,1
22,0 to 12,0 to 0,70 to
— 309LNb 0,04 1,00 0,5 to 2,5 0,040 0,030 0,75 0,75 — —
25,0 14,0 1,00
22,0 to 12,0 to 0,70 to
e
(23 12 Nb) 309Nb 0,12 1,00 0,5 to 2,5 0,04 0,03 0,75 0,75 — —
25,0 14,0 1,00
22,0 to 12,0 to
— 309Mo 0,12 1,00 0,5 to 2,5 0,04 0,03 2,0 to 3,0 0,75 — — —
25,0 14,0
22,0 to 11,0 to
e
23 12 2 L (309LMo) 0,04 1,2 2,5 0,030 0,025 2,0 to 3,0 0,75 — — —
25,0 14,0
22,0 to 12,0 to
e
(23 12 2 L) 309LMo 0,04 1,00 0,5 to 2,5 0,04 0,03 2,0 to 3,0 0,75 — — —
25,0 14,0
27,0 to
d e
29 9 (312) 0,15 1,2 2,5 0,035 0,025 8,0 to 12,0 0,75 0,75 — — —
31,0
28,0 to
e
(29 9) 312 0,15 1,00 0,5 to 2,5 0,04 0,03 8,0 to 10,5 0,75 0,75 — — —
32,0
Heat-resisting types
14,5 to
e
16 8 2 (16-8-2) 0,08 0,60 2,5 0,030 0,025 7,5 to 9,5 1,5 to 2,5 0,75 — — —
16,5
14,5 to
e
(16 8 2) 16-8-2 0,10 0,60 0,5 to 2,5 0,03 0,03 7,5 to 9,5 1,0 to 2,0 0,75 — — —
16,5
0,06 to 1,0 to 20,5 to 0,10 to
21 10 N — 0,3 to 1,0 0,02 0,01 9,5 to 11,0 0,5 0,3 — Ce 0,05
0,09 2,0 22,5 0,20
ISO 3581:2023(E)
Table 3 (continued)
a,b,c
Chemical composition
Symbol classification by:
% (by mass)
Nominal Other
e
composition Alloy type speci-
C Si Mn P S Cr Ni Mo Cu Nb + Ta N
d,e
(ISO 3581-B) fied ele-
f
(ISO 3581-A) ments
24,0 to
25 4 — 0,15 1,2 2,5 0,030 0,025 4,0 to 6,0 0,75 0,75 — — —
27,0
0,04 to 22,0 to 12,0 to
e
(22 12) 309H 1,00 0,5 to 2,5 0,04 0,03 0,75 0,75 — — —
0,15 25,0 14,0
0,06 to 23,0 to 18,0 to
e
25 20 (310) 1,2 1,0 to 5,0 0,030 0,025 0,75 0,75 — — —
0,20 27,0 22,0
0,08 to 25,0 to 20,0 to
e
(25 20) 310 0,75 1,0 to 2,5 0,03 0,03 0,75 0,75 — — —
0,20 28,0 22,5
0,35 to 23,0 to 18,0 to
e
25 20 H (310H) 1,2 2,5 0,030 0,025 0,75 0,75 — — —
0,45 27,0 22,0
0,35 to 25,0 to 20,0 to
e
(25 20 H) 310H 0,75 1,0 to 2,5 0,03 0,03 0,75 0,75 — — —
0,45 28,0 22,5
25,0 to 20,0 to 0,70 to
— 310Nb 0,12 0,75 1,0 to 2,5 0,03 0,03 0,75 0,75 — —
28,0 22,0 1,00
25,0 to 20,0 to
— 310Mo 0,12 0,75 1,0 to 2,5 0,03 0,03 2,0 to 3,0 0,75 — — —
28,0 22,0
14,0 to 33,0 to
e
18 36 (330) 0,25 1,2 2,5 0,030 0,025 0,75 0,75 — — —
18,0 37,0
0,18 to 14,0 to 33,0 to
e
(18 36) 330 1,00 1,0 to 2,5 0,04 0,03 0,75 0,75 — — —
0,25 17,0 37,0
0,35 to 14,0 to 33,0 to
— 330H 1,00 1,0 to 2,5 0,04 0,03 0,75 0,75 — — —
0,45 17,0 37,0
Precipitation hardening type
0,25 to 16,00 to 3,25 to 0,15 to
...