prEN 10210-1

Hot-finished steel structural hollow sections - Part 1: Technical delivery conditions

This document specifies technical delivery conditions for hot-finished seamless, electric welded and submerged arc welded steel structural hollow sections of circular, square, rectangular or elliptical forms.
It applies to hollow sections formed hot, with or without subsequent heat treatment, or formed cold with subsequent heat treatment above 580 °C to obtain equivalent mechanical properties to those obtained in the hot formed product.
NOTE 1   The requirements for tolerances, dimensions and sectional properties are specified in EN 10210-2.
NOTE 2   The provisions that apply under the Construction Products Regulations (CPR) are specified in EN 10380.
NOTE 3   The attention of users is drawn to the fact that whilst cold formed grades in EN 10219-1 can have equivalent mechanical properties to hot-finished grades in this document the sectional properties of square and rectangular hollow sections in EN 10210-2 and EN 10219-2 are not equivalent.
NOTE 4   A range of material grades is specified in this standard and the user should select the grade most appropriate to the intended use and service conditions. The grades and mechanical properties of the finished hollow sections are generally comparable with those in EN 10025-2, EN 10025-3, EN 10025-4, EN 10025-5 and EN 10025-6.
NOTE 5   The requirements for seamless and welded steel structural hollow sections for use in offshore structures are covered in EN 10225.
NOTE 6   Spiral welded hollow sections must be used with caution in applications involving dynamic behaviour (fatigue stress) as, up to now, there is insufficient data regarding their performance.

Warmgefertigte Hohlprofile für den Stahlbau - Teil 1: Technische Lieferbedingungen

Dieses Dokument legt die technischen Lieferbedingungen für warmgefertigte nahtlose, elektrisch und unterpulvergeschweißte Hohlprofile mit kreisförmiger, quadratischer, rechteckiger oder elliptischer Form fest.
Sie gilt für warmgefertigte Hohlprofile mit oder ohne nachfolgende Wärmebehandlung sowie für kaltgeformte Hohlprofile mit einer anschließenden Wärmebehandlung oberhalb von 580 °C um gleichwertige mechanische Eigenschaften wie bei den warmgeformten Erzeugnissen zu erzielen.
ANMERKUNG 1   Die Anforderungen an die Grenzabmaße, Maße und statischen Werte sind in EN 10210 2 festgelegt.
ANMERKUNG 2   Die unter der Bauproduktenverordnung (CPR) anzuwendenden Vorschriften sind in EN 10380 festgelegt.
ANMERKUNG 3   Der Anwender wird darauf aufmerksam gemacht, dass die kaltgeformten Hohlprofile nach EN 10219 1 zwar vergleichbare mechanische Eigenschaften zu den warmgefertigten Hohlprofilen nach diesem Dokument aufweisen können, dass aber die Maße und statischen Werte von quadratischen und rechteckigen Hohlprofilen nach EN 10210 2 und EN 10219 2 nicht vergleichbar sind.
ANMERKUNG 4   Eine Anzahl von Stahlsorten ist in diesem Dokument festgelegt und der Anwender sucht die geeignetste Sorte für die beabsichtigte Verwendung aus. Die Sorten und die mechanischen Eigenschaften der fertigen Hohlprofile sind im Allgemeinen vergleichbar mit den Sorten die in EN 10025 2, EN 10025 3, EN 10025 4, EN 10025 5 und EN 10025 6 aufgeführt sind.
ANMERKUNG 5   Nahtlose und geschweißte Hohlprofile für Offshore-Konstruktionen werden in der Europäischen Normenserie EN 10225 behandelt.
ANMERKUNG 6   Es wird erwartet, dass spiralnahtgeschweißte Hohlprofile mit Vorsicht bei Anwendungen, die dynamische Beanspruchung (Ermüdungsbelastung) einschließen, verwendet werden, da es bis heute nur unzureichende Daten bezüglich des Verhaltens gibt.

Profils creux de construction en aciers finis à chaud - Partie 1 : Conditions techniques de livraison

Le présent document spécifie les conditions techniques de livraison pour les profils creux de construction finis à chaud des aciers sans soudure, soudés électriquement et soudés à l’arc immergé de forme circulaire, carrée, rectangulaire ou elliptique.
Il s’applique aux profils creux formés à chaud, avec ou sans traitement thermique ultérieur, ou formés à froid avec traitement thermique ultérieur supérieur à 580 °C afin d’obtenir des caractéristiques mécaniques équivalentes à celles des produits formés à chaud.
NOTE 1   Les exigences relatives aux tolérances, dimensions et caractéristiques de profil sont spécifiées dans l’EN 10210-2.
NOTE 2   Les dispositions qui s'appliquent en vertu des Règlements sur les Produits de Construction (RPC) sont spécifiées dans l’EN 10380.
NOTE 3   L’attention des utilisateurs est attirée sur le fait que, même si les nuances formées à froid de l'EN 10219-3 peuvent avoir des caractéristiques mécaniques équivalentes aux nuances finies à chaud du présent document, les caractéristiques de section des profils creux carrés et rectangulaires de l’EN 10210-2 et de l’EN 10219-2 ne sont pas équivalentes.
NOTE 4   Une gamme de nuances de matériau est spécifiée dans le présent document, et l’utilisateur sélectionne la nuance la plus appropriée à l’utilisation et aux conditions de service prévues. Les nuances et les caractéristiques mécaniques des profils creux finis sont généralement comparables à celles des EN 10025 2, EN 10025 3, EN 10025 4, EN 10025 5 et EN 10025 6.
NOTE 5   Les exigences pour les profils creux de construction en aciers sans soudure et soudés destinés aux structures marines sont couvertes par l’EN 10225.
NOTE 6   Les profils creux soudés en spirale doivent être utilisés avec prudence dans les applications impliquant un comportement dynamique (contrainte en fatigue) important car jusqu'à présent, les données concernant leurs performances sont insuffisantes.

Vroče izdelani votli profili iz jekla - 1. del: Tehnični dobavni pogoji

Ta dokument določa tehnične pogoje dobave za vroče oblikovane brezšivne, električno varjene in potopno obločno varjene jeklene strukturne votle profile okroglih, kvadratnih, pravokotnih ali eliptičnih oblik.
Uporablja se za votle profile, oblikovane vroče, z ali brez naknadne toplotne obdelave, ali oblikovane hladno z naknadno toplotno obdelavo nad 580 °C, da se dosežejo enakovredne mehanske lastnosti tistim, pridobljenim pri vroče oblikovanem izdelku.
OPOMBA 1 Zahteve za tolerance, dimenzije in lastnosti presekov so določene v EN 10210-2.
OPOMBA 2 Določbe, ki veljajo v skladu z Uredbo o gradbenih proizvodih (CPR), so določene v EN 10380.
OPOMBA 3 Uporabnike opozarjamo, da čeprav lahko hladno oblikovani razredi v EN 10219-1 imajo enakovredne mehanske lastnosti kot vroče oblikovani razredi v tem dokumentu, lastnosti presekov kvadratnih in pravokotnih votlih profilov v EN 10210-2 in EN 10219-2 niso enakovredne.
OPOMBA 4 V tem standardu je določen razpon materialnih razredov, uporabnik pa naj izbere razred, ki je najbolj primeren za predvideno uporabo in pogoje storitve. Razredi in mehanske lastnosti končnih votlih profilov so na splošno primerljivi s tistimi v EN 10025-2, EN 10025-3, EN 10025-4, EN 10025-5 in EN 10025-6.
OPOMBA 5 Zahteve za brezšivne in varjene jeklene strukturne votle profile za uporabo v morskih strukturah so zajete v EN 10225.
OPOMBA 6 Spiralno varjene votle profile je treba uporabljati previdno v aplikacijah, ki vključujejo dinamično obnašanje (utrujenostni napor), saj do sedaj ni dovolj podatkov o njihovi zmogljivosti.

General Information

• Status: Not Published
• Publication Date: 23-Apr-2026
• ICS: 77.140.75 - Steel pipes and tubes for specific use
• Technical Committee: ECISS/TC 103 - Structural steels other than reinforcements
• Drafting Committee: ECISS/TC 103/WG 3 - Hollow sections
• Current Stage: 4020 - Submission to enquiry - Enquiry
• Start Date: 26-Mar-2026
• Due Date: 04-Dec-2024
• Completion Date: 26-Mar-2026
• Ref Project: oSIST prEN 10210-1:2026 - Hot-finished steel structural hollow sections - Part 1: Technical delivery conditions

Relations

• Revises: EN 10210-1:2006 - Hot finished structural hollow sections of non-alloy and fine grain steels - Part 1: Technical delivery conditions
• Effective Date: 17-Jan-2024

Overview

prEN 10210-1:2026 is a CEN draft European Standard that defines the technical delivery conditions for hot-finished steel structural hollow sections. This standard applies to both seamless and welded hollow sections - including those produced by electric welding and submerged arc welding. The sections may be circular, square, rectangular, or elliptical in shape. The document is intended for hollow sections formed hot, with or without subsequent heat treatment, or cold-formed and then heat treated at temperatures above 580 °C to achieve equivalent mechanical properties to hot-formed products.

This standard is a key reference for engineers, fabricators, and construction professionals seeking to ensure compliance and achieve high performance in steel structural hollow sections for construction and industrial uses.

Key Topics

• Scope of Product:

  • Covers hot-finished circular, square, rectangular, and elliptical steel hollow sections.
  • Includes seamless, electric welded, and submerged arc welded types.
  • Applies to products formed either hot or cold, with subsequent heat treatment when required.

• Technical Delivery Conditions:

  • Specifies the chemical composition, mechanical properties, and manufacturing processes.
  • Details mandatory and optional order information for manufacturers and purchasers.
  • Outlines the classification and designation of structural hollow sections, using a clear system for grade and mechanical property identification.

• Inspection and Testing:

  • Sets requirements for inspection frequency, sample preparation, and mechanical/chemical testing.
  • Defines procedures for non-destructive testing (NDT), weld inspections, and quality certifications.

• Compliance and Regulatory References:

  • Refers to EN 10210-2 for tolerances, dimensions, and sectional properties.
  • Aligns with Construction Products Regulation (CPR) requirements as specified in EN 10380.
  • Encourages selection of grades in accordance with intended use and service conditions.

Applications

Hot-finished steel structural hollow sections manufactured and certified to prEN 10210-1 are widely used in:

• Building and Construction:

  • Structural frameworks for commercial, industrial, and residential buildings.
  • Bridges, stadiums, and heavy civil engineering works.

• Industrial Applications:

  • Machinery frames
  • Conveyor structures
  • Plant and equipment supporting structures

• Infrastructure:

  • Columns, beams, and structural supports in bridges and road infrastructure.
  • Utility supports, pylons, and overhead structures.

• Offshore and Specialized Use:

  • While general offshore requirements are addressed in EN 10225, the standard provides foundational requirements for seamless and welded hollow sections in various environments.
  • Caution is recommended with spiral welded hollow sections under dynamic or fatigue-stressed applications due to limited performance data.

Benefits for users include:

• Consistent mechanical properties and quality assurance.
• Reliable weldability and compatibility with hot-dip galvanizing.
• Selection of a wide range of grades to match performance and durability requirements.
• Harmonization with European and international standards, supporting regulatory and market acceptance.

Related Standards

For a comprehensive understanding and correct application of prEN 10210-1, users should consult:

• EN 10210-2 - Tolerances, dimensions, and sectional properties for hot finished steel hollow sections.
• EN 10219-1 & EN 10219-2 - Standards for cold formed hollow sections.
• EN 10025 Series (2–6) - Reference for comparable steel grades and mechanical properties.
• EN 10380 - Provisions for Construction Products Regulation (CPR) compliance.
• EN 10225 - Specific requirements for offshore structural hollow sections.
• ISO/EN references (e.g., EN 10020, EN 10204, EN ISO 6892-1) for relevant definitions, testing procedures, and inspection documents.

By following prEN 10210-1 and its related standards, stakeholders in the steel and construction industries can ensure the structural integrity, safety, and regulatory compliance of steel structural hollow section products used across a variety of demanding applications.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2026
Vroče izdelani votli profili iz jekla - 1. del: Tehnični dobavni pogoji
Hot-finished steel structural hollow sections - Part 1: Technical delivery conditions
Warmgefertigte Hohlprofile für den Stahlbau - Teil 1: Technische Lieferbedingungen
Profils creux de construction en aciers finis à chaud - Partie 1 : Conditions techniques de
livraison
Ta slovenski standard je istoveten z: prEN 10210-1
ICS:
77.140.70 Jekleni profili Steel profiles
77.140.75 Jeklene cevi in cevni profili Steel pipes and tubes for
za posebne namene specific use
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2026
ICS 77.140.75 Will supersede EN 10210-1:2006
English Version
Hot-finished steel structural hollow sections - Part 1:
Technical delivery conditions
Profils creux de construction en aciers finis à chaud - Warmgefertigte Hohlprofile für den Stahlbau - Teil 1:
Partie 1 : Conditions techniques de livraison Technische Lieferbedingungen
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 459/SC 3.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 10210-1:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions and symbols . 7
3.1 Terms and definitions . 7
3.2 Symbols. 8
4 Classification and designation . 9
4.1 Classification . 9
4.2 Designation . 9
5 Information to be obtained by the manufacturer . 10
5.1 Mandatory information . 10
5.2 Options . 11
5.3 Example of an order . 11
6 Manufacturing process . 11
6.1 General . 11
6.2 Steel manufacturing process . 12
6.3 Grain structure . 12
6.4 Structural hollow section manufacturing process . 12
6.5 Delivery condition . 12
7 Requirements . 13
7.1 Chemical composition . 13
7.2 Mechanical properties . 15
7.3 Technological properties . 16
7.3.1 Weldability . 16
7.3.2 Hot-dip-zinc coating . 16
7.4 Product supply condition . 17
7.5 Non-destructive testing . 17
7.6 Tolerances and mass . 18
8 Inspection . 18
8.1 Types of inspection . 18
8.2 Types and contents of inspection documents. 18
8.3 Summary of inspection . 19
9 Frequency of testing and preparation of samples and test pieces . 20
9.1 Frequency of tests . 20
9.2 Selection and preparation of samples for product analysis . 21
9.3 Location and orientation of samples for the mechanical tests . 21
9.3.1 Tensile test pieces. 21
9.3.2 Impact test pieces . 21
9.4 Preparation of test pieces for mechanical tests . 21
9.4.1 General . 21
9.4.2 Tensile test pieces. 22
9.4.3 Impact test pieces . 22
10 Test methods . 22
10.1 Chemical analysis . 22
10.2 Mechanical tests . 22
10.2.1 Test temperature . 22
10.2.2 Tensile test . 22
10.2.3 Impact test . 23
10.3 Visual inspection and dimensional check . 23
10.4 Non-destructive testing . 23
10.4.1 General . 23
10.4.2 Weld seams of electric welded sections . 23
10.4.3 Weld seams of submerged arc welded sections . 24
10.4.4 Full peripheral NDT for imperfections . 24
10.4.5 Ultrasonic testing for laminar imperfections . 24
10.5 Retests, sorting and reprocessing . 24
11 Marking . 24
Annex A (normative) Structural hollow sections of non-alloy quality steels — Chemical
composition and mechanical properties . 26
Annex B (normative) Structural hollow sections of normalized/normalized rolled steels —
Chemical composition and mechanical properties . 28
Annex C (normative) Structural hollow sections of thermomechanical formed steels —
Chemical composition and mechanical properties . 31
Annex D (normative) Structural hollow sections of quenched and tempered steels —
Chemical composition and mechanical properties . 36
Annex E (normative) Structural hollow sections of steels with improved atmospheric
corrosion resistance — Chemical composition and mechanical properties . 41
Annex F (normative) Location of samples and test pieces . 43
Annex G (informative) Hot finished hollow section production processes, manufacturing
routes and delivery conditions . 45
Bibliography . 48

European foreword
This document (prEN 10210-1:2026) has been prepared by Technical Committee CEN/TC 459/SC 3
“Structural steels other than reinforcements”, the secretariat of which is held by DIN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 10210-1:2006 and EN 10210-3:2020.
This document includes the following significant technical changes with respect to the previous version:
— part 1 and part 3 were merged;
— the chemical compositions of some grades were slightly changed;
— Annex ZA and provisions that apply under the Construction Products Regulation were moved to
EN 10380;
— editorial revised.
This standard consists of the following parts:
— EN 10380, Finished non-alloy and alloy steel products for structural use
— EN 10210-1, Hot finished steel structural hollow sections - Part 1: Technical delivery conditions
— EN 10210-2, Hot finished steel structural hollow sections - Part 2: Tolerances, dimensions and
sectional properties
It forms part of a series of standards on hollow sections together with EN 10219-1 and EN 10219-2.

1 Scope
This document specifies technical delivery conditions for hot-finished seamless, electric welded and
submerged arc welded steel structural hollow sections of circular, square, rectangular or elliptical forms.
It applies to hollow sections formed hot, with or without subsequent heat treatment, or formed cold with
subsequent heat treatment above 580 °C to obtain equivalent mechanical properties to those obtained in
the hot formed product.
NOTE 1 The requirements for tolerances, dimensions and sectional properties are specified in EN 10210-2.
NOTE 2 The provisions that apply under the Construction Products Regulations (CPR) are specified in EN 10380.
NOTE 3 The attention of users is drawn to the fact that whilst cold formed grades in EN 10219-1 can have
equivalent mechanical properties to hot-finished grades in this document the sectional properties of square and
rectangular hollow sections in EN 10210-2 and EN 10219-2 are not equivalent.
NOTE 4 A range of material grades is specified in this document and the user selects the grade most appropriate
to the intended use and service conditions. The grades and mechanical properties of the finished hollow sections
are generally comparable with those in EN 10025-2, EN 10025-3, EN 10025-4, EN 10025-5 and EN 10025-6.
NOTE 5 The requirements for seamless and welded steel structural hollow sections for use in offshore structures
are covered in EN 10225.
NOTE 6 Spiral welded hollow sections must be used with caution in applications involving dynamic behaviour
(fatigue stress) as, up to now, there is insufficient data regarding their performance.
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.
EN 1011-1, Welding — Recommendations for welding of metallic materials — Part 1: General guidance for
arc welding
EN 1011-2, Welding — Recommendations for welding of metallic materials — Part 2: Arc welding of ferritic
steels
EN 10020, Definition and classification of grades of steel
EN 10021, General technical delivery conditions for steel products
EN 10027-1, Designation systems for steels — Part 1: Steel names
EN 10027-2, Designation systems for steels — Part 2: Numerical system
EN 10160, Ultrasonic testing of steel flat product of thickness equal or greater than 6 mm (reflection
method)
EN 10168, Steel products — Inspection documents — List of information and description
EN 10204, Metallic products — Types of inspection documents
EN 10210-2, Hot finished steel structural hollow sections — Part 2: Tolerances, dimensions and sectional
properties
CEN/TR 10261, Iron and steel — European standards for the determination of chemical composition
EN 10266, Steel tubes, fittings and structural hollow sections — Symbols and definitions of terms for use in
product standards
EN ISO 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method (ISO 148-1)
EN ISO 377, Steel and steel products — Location and preparation of samples and test pieces for mechanical
testing (ISO 377)
EN ISO 643, Steels — Micrographic determination of the apparent grain size (ISO 643)
EN ISO 1461, Hot dip galvanized coatings on fabricated iron and steel articles — Specifications and test
methods (ISO 1461)
EN ISO 2566-1, Steel — Conversion of elongation values — Part 1: Carbon and low alloy steels (ISO 2566-1)
EN ISO 4885, Ferrous materials — Heat treatments — Vocabulary (ISO 4885)
EN ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
(ISO 6892-1)
EN ISO 9606-1, Qualification testing of welders — Fusion welding — Part 1: Steels (ISO 9606-1)
EN ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel (ISO 9712)
EN ISO 10893-2, Non-destructive testing of steel tubes — Part 2: Automated eddy current testing of
seamless and welded (except submerged arc-welded) steel tubes for the detection of imperfections
(ISO 10893-2)
EN ISO 10893-3, Non-destructive testing of steel tubes — Part 3: Automated full peripheral flux leakage
testing of seamless and welded (except submerged arc-welded) ferromagnetic steel tubes for the detection
of longitudinal and/or transverse imperfections (ISO 10893-3)
EN ISO 10893-6, Non-destructive testing of steel tubes — Part 6: Radiographic testing of the weld seam of
welded steel tubes for the detection of imperfections (ISO 10893-6)
EN ISO 10893-7, Non-destructive testing of steel tubes — Part 7: Digital radiographic testing of the weld
seam of welded steel tubes for the detection of imperfections (ISO 10893-7)
EN ISO 10893-8, Non-destructive testing of steel tubes — Part 8: Automated ultrasonic testing of seamless
and welded steel tubes for the detection of laminar imperfections (ISO 10893-8)
EN ISO 10893-9, Non-destructive testing of steel tubes — Part 9: Automated ultrasonic testing for the
detection of laminar imperfections in strip/plate used for the manufacture of welded steel tubes
(ISO 10893-9)
EN ISO 10893-10, Non-destructive testing of steel tubes — Part 10: Automated full peripheral ultrasonic
testing of seamless and welded (except submerged arc-welded) steel tubes for the detection of longitudinal
and/or transverse imperfections (ISO 10893-10)
EN ISO 10893-11, Non-destructive testing of steel tubes — Part 11: Automated ultrasonic testing of the weld
seam of welded steel tubes for the detection of longitudinal and/or transverse imperfections (ISO 10893-11)
EN ISO 14284, Steel and iron — Sampling and preparation of samples for the determination of chemical
composition (ISO 14284)
EN ISO 14713-2, Zinc coatings — Guidelines and recommendations for the protection against corrosion of
iron and steel in structures — Part 2: Hot dip galvanizing (ISO 14713-2)
EN ISO 15607, Specification and qualification of welding procedures for metallic materials — General rules
(ISO 15607)
EN ISO 15609-1, Specification and qualification of welding procedures for metallic materials — Welding
procedure specification — Part 1: Arc welding (ISO 15609-1)
EN ISO 15614-1, Specification and qualification of welding procedures for metallic materials — Welding
procedure test — Part 1: Arc and gas welding of steels and arc welding of nickel and nickel alloys
(ISO 15614-1)
ISO 11484, Steel products — Employer’s qualification system for non-destructive testing (NDT) personnel
SNT TC-1A, Personnel Qualification and Certification in non-destructive Testing
3 Terms and definitions and symbols
3.1 Terms and definitions
For the purpose of this document the following terms and definitions apply in addition to or where
different from those in EN 10020, EN 10021, EN 10266 and EN ISO 4885.
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/
— IEC Electropedia: available at https://www.electropedia.org/
3.1.1
hot finished
hollow sections formed hot, with or without subsequent heat treatment, or formed cold with subsequent
heat treatment above 580 °C to obtain equivalent metallurgical conditions to those obtained in the hot
formed product
3.1.2
cold forming
process where the forming to final shape of the welded hollow section is carried out at ambient
temperature
Note 1 to entry: Circular hollow sections produced from normalized strip with a normalized weld seam and with a
cold forming ratio of D/T ≥ 20 may be classified as hot-finished hollow sections.
3.1.3
normalizing rolling
rolling process in which the final deformation is carried out in a certain temperature range leading to a
material condition equivalent to that obtained after normalizing so that the specified values of the
mechanical properties are retained even after subsequent normalizing
3.1.4
thermomechanical forming
simultaneously performed forming process and heat treatment in which the final deformation from
round to rectangular/square/elliptical hollow sections is carried out in a certain temperature range
above 580 °C leading to a material condition with certain properties which cannot be achieved or
repeated by heat treatment alone
Note 1 to entry: Thermomechanical rolling leading to the delivery condition M can include processes with an
increased cooling rate with or without tempering including self-tempering but excluding direct quenching and
quenching and tempering.
Note 2 to entry: In some publications the word TMCP (Thermomechanical Control Process) is also used.
3.1.5
steel with improved atmospheric corrosion resistance
steel in which a certain number of alloying elements has been added in order to increase its resistance to
atmospheric corrosion, by forming an auto-protective oxide layer on the base metal under the influence
of weather conditions
Note 1 to entry: Steel with improved atmospheric corrosion resistance is often called weathering steel.
Note 2 to entry: Additional information for the use of steel with improved atmospheric corrosion resistance is
given in Annex E.
3.1.6
quenching and tempering
process which consists of the following two steps:
— first quenching, where the steel is heated up above Ac temperature and then rapidly cooled down in
liquids to create a process specific grain structure;
— afterwards tempering, during which the steel is heated up to a certain temperature to adjust the
desired properties and cooled down in air afterwards
3.1.7
fine grain steel
steel with fine grain structure with an equivalent index of ferritic grain size ≥ 6
Note 1 to entry: For the determination of grain sizes except for +QT steels, see EN ISO 643.
3.1.8
hot-dip zinc coating
application of a zinc coating by immersing the prepared strip or hollow section in a molten bath
containing a zinc content of at least 98 %
3.2 Symbols
For the purposes of this document, the symbols defined in EN 10266 apply.
4 Classification and designation
4.1 Classification
4.1.1 Within the grades of non-alloy steels given in Annex A, four qualities JR, J0, J2 and K2 are specified.
These differ in respect of specified impact requirements, limits on values of various elements, with
particular reference to sulphur and phosphorus, and the inspection and testing requirements.
In accordance with the classification system in EN 10020, all steel grades in Annex A are non-alloy quality
steels.
4.1.2 Within the grades of steels given in Annex B, C and D seven qualities N, NL, M, ML, Q, QL and QL1
are specified. These differ in respect of the carbon, sulphur and phosphorus content, low temperature
impact properties, production process, heat treatment and grain size.
In accordance with the classification system in EN 10020, steel grades S275NH, S275NLH, S355NH and
S355NLH are non-alloy quality steels and all other steel grades are alloy special steels.
4.1.3 Within the grades of steels given in Annex E, three qualities J0, J2 and K2 are specified. These
differ in respect of specified impact requirements and limits on values of various elements.
In accordance with the classification system in EN 10020, all steel grades in Annex E are alloy special
steels.
4.2 Designation
4.2.1 For the products covered by this document the steel names shall be allocated in accordance with
EN 10027-1; the steel numbers shall be allocated in accordance with EN 10027-2.
4.2.2 The designation of steel hollow sections consists of:
a) the number of this document (EN 10210-1);
b) the capital letter S for structural steel;
c) the indication of the minimum specified yield strength for thicknesses ≤ 16 mm expressed in MPa;
d) further designations for either:
1) non-alloy structural steels:
i) the capital letters JR for the qualities with specified impact properties at room temperature;
ii) the characters J0 for the qualities with specified impact properties at 0 °C;
iii) the characters J2 or K2 for the qualities with specified impact properties at −20 °C; or
2) normalized/normalized rolled structural steels:
i) capital letter N to indicate normalized or normalized rolled with specified impact properties
at −20 °C (see 6.5);
ii) capital letters NL for qualities with specified impact properties at –50 °C; or
3) thermomechanical formed structural steels:
i) capital letter M to indicate thermomechanical rolled with specified impact properties at
−20 °C (see 6.5);
ii) capital letters ML for qualities with specified impact properties at –50 °C; or
4) structural steels in the quenched and tempered condition:
i) capital letter Q to indicate the quenched and tempered condition with specified impact
properties at −20 °C (see 6.5);
ii) capital letters QL or QL1 for qualities with specified impact properties at –40 or –50 °C; or
5) steels with improved atmospheric corrosion resistance:
i) the characters J0 for the qualities with specified impact properties at 0 °C;
ii) the characters J2 or K2 for the qualities with specified impact properties at −20 °C; and
iii) the letter W (weather) for improved atmospheric corrosion resistance; and
e) the capital letter H to indicate hollow sections.
EXAMPLE 1 Hollow section made of structural steel (S) with a specified minimum yield strength for a thickness
not greater than 16 mm of 275 MPa, with a minimum impact energy value of 27 J at 0 °C (J0), hollow section (H):
EN 10210-1 — S275J0H
or
EN 10210-1 — 1.0149
EXAMPLE 2 Hollow section made of structural steel (S) with a specified minimum yield strength for a thickness
not greater than 16 mm of 355 MPa, normalized condition (N), with a minimum impact energy value of 27 J at −50 °C
(L), hollow section (H):
EN 10210-1 — S355NLH
or
EN 10210-1 — 1.0549
5 Information to be obtained by the manufacturer
5.1 Mandatory information
The following information shall be contained in the order document at the time of enquiry and order:
a) the quantity (mass or total length);
b) details of the product form:
1) HFCHS = hot finished circular hollow sections;
2) HFRHS = hot finished square or rectangular hollow sections;
3) HFEHS = hot finished elliptical hollow sections;
c) the name of the standard for dimensions and tolerances (EN 10210-2);
d) the dimensions and the type of length, length range or length (see EN 10210-2);
e) the steel designation (see 4.2).
5.2 Options
A number of options are specified in this document. These are listed below with appropriate clause
references. In the event that the purchaser does not indicate a wish to implement any of these options at
the time of enquiry and order, the hollow sections shall at least be supplied in accordance with the basic
specification.
1.1 Internal weld bead trimmed (see 6.4.2);
1.2 empty (Option for EN 10219-2)
1.3 Product analysis (see 7.1.1);
1.4 Cr, Cu, Mo, Ni, Ti and V cast analysis contents to be reported for non-alloy quality steels (see
7.1.2);
1.5 Tensile test in corner region (see 7.2.1);
1.6 Impact test in corner region (see 7.2.2).
1.7 Verification of impact properties for qualities JR and J0 (see 7.2.3);
1.8 The product shall have a chemical composition suitable for hot-dip-zinc coating (see 7.3.2);
1.9 Weld repairs to the body of structural steel hollow sections are permitted (see 7.4.4);
1.10 Full peripheral NDT (non-destructive testing) of circular tubes for imperfections - not possible
for elliptical, rectangular, square and SAW (submerged arc welded) hollow sections (see 7.5);
1.11 Ultrasonic testing for laminar imperfections (see 7.5);
1.12 Inspection certificate 3.1 for steel grades S235JRH, S275J0H, S355J0H of Annex A and S355J0WH
of Annex E instead of a test report 2.2 (see 8.1);
1.13 Inspection certificate 3.2.

5.3 Example of an order
100 t hot finished square hollow section in accordance with EN 10210-2 with specified outside
dimensions 100 mm × 100 mm and wall thickness of 8 mm of 12 m approximate length, grade S355J0H
according to EN 10210-1, verified impact properties at 0 °C (Option 1.7), supplied with inspection
certificate 3.1 (Option 1.12) and with regulatory marking according to EN 10380:
100 t– HFRHS – EN 10210-2 —100 × 100 × 8 – approximate length 12 m EN 10210-1 — S355J0H –
Options 1.7 and 1.12
6 Manufacturing process
6.1 General
Structural hot finished hollow sections of non-alloy steels shall conform to the requirements of Annex A.
Structural hot finished hollow sections of normalized/normalized rolled, thermomechanical rolled and
quenched and tempered steels shall conform to Annexes B to D and steels with improved atmospheric
corrosion resistance shall conform to the requirements of Annex E.
In addition, the general technical delivery requirements specified in EN 10021 shall apply.
6.2 Steel manufacturing process
6.2.1 The steel manufacturing process shall be at the discretion of the hollow section manufacturer
with the exception that the open hearth (Siemens-Martin) process shall not be employed.
6.2.2 The method of deoxidation shall be as specified in Tables A.1, B.1, C.1, D.1 and E.1.
6.3 Grain structure
The steels grades given in Annexes B to D shall have a ferritic grain size equal to or finer than 6 when
measured in accordance with EN ISO 643 (see 7.2.4).
6.4 Structural hollow section manufacturing process
6.4.1 Structural hollow sections shall be manufactured by a seamless or by a welding process (see
informative Annex G). Welded sections manufactured by a continuous process shall not include the welds
used to join the lengths of strip prior to forming the hollow section, except as permitted in 10.4.3.
6.4.2 Electric welded hollow sections shall be supplied with the external weld bead trimmed to an
essentially flush condition. Trimming of the internal weld bead is at the discretion of the manufacturer
unless Option 1.1 is specified.
Option 1.1 Electric welded hollow sections shall be supplied with the internal weld bead trimmed,
the maximum height of the internal weld bead after trimming shall be agreed at the time of enquiry and
order.
6.4.3 All NDT activities shall be carried out by qualified and competent level 1, 2 and/or 3 personnel
authorized to operate by the employer.
The qualification shall be in accordance with ISO 11484 or ASNT TC-1A or EN ISO 9712.
It is recommended that the level 3 personnel be certified in accordance with EN ISO 9712 or ASNT.
The operating authorisation issued by the employer shall be in accordance with a written procedure.
NDT operations shall be authorised by a level 3 NDT individual approved by the employer.
NOTE The definition of levels 1, 2 and 3 can be found in the appropriate standards, e.g. EN ISO 9712 and
ISO 11484.
6.5 Delivery condition
The products shall be delivered in the conditions indicated below:
— Qualities JR, J0, J2 and K2 — hot finished,
— Qualities N and NL — full body normalized. Normalized includes normalized rolled and normalized
formed,
— Qualities M and ML – thermomechanical formed,
— Qualities Q, QL and QL1 — quenched and tempered.
For steels of qualities JR, J0, J2, K2 of Annex A and steel of qualities N, NL of Annex B it may be necessary
for hollow sections to apply accelerated cooling after austenitizing to achieve the intended structure, or
liquid quenching and tempering to achieve the specified mechanical properties. The decision shall be left
to the discretion of the manufacturer, but shall be stated to the purchaser at the time of enquiry and order.
Hollow sections treated in such a way by quenching and tempering shall be designated by the steel name
supplemented with the symbol "+QT".
7 Requirements
7.1 Chemical composition
7.1.1 The chemical composition determined by the cast analysis and reported by the steel producer
shall comply to the requirements given in Tables A.1, B.1, C.1, D.1 or E.1.
The maximum carbon equivalent value (CEV) for all grades, based on the cast analyses, given in Tables
A.2, B.2, C.2, D.2 and E.2 shall apply.
When determining the CEV, the following formula of the International Institute of Welding (IIW) shall be
used:
Mn Cr++Mo V Ni+ Cu
CEV=C+ + +
6 5 15
In addition to the cast analysis the following option can be specified by the purchaser at the time of
enquiry and order:
Option 1.3 For products supplied with specific inspection and testing, a product analysis shall be
reported.
Deviations of the product analysis from the specified limits of the cast analysis shall be in accordance with
Table 1.
7.1.2 For non-alloy steel products with specific inspection (3.1 or 3.2) the following option may be
specified:
Option 1.4 The recording on the inspection certificate of the Cr, Cu, Mo, Ni, Ti and V content (cast
analysis).
7.1.3 When products are supplied with a control on Si e.g. for hot-dip zinc-coating there could be a
need, for certain grades and thicknesses, to increase the content of other elements such as C and Mn, to
achieve the required mechanical properties. In such cases the maximum carbon equivalent values of
Tables A.2 to E.2 may be increased as follows:
— for Si ≤ 0,04 %, increase the value of the CEV by 0,02;
— for Si ≤ 0,25 %, increase the value of the CEV by 0,01.
Table 1 — Permissible deviations of the product analysis from the specified limits of the cast
analysis specified in Tables A.1, B.1, C.1, D.1 and E.1
Permissible deviation of the
Permissible maximum content in product analysis from
Element
the cast analysis specified limits for the cast
analysis
% by mass % by mass
≤ 0,20 + 0,02
C
> 0,20 + 0,03
≤ 0,60 + 0,05
Si
> 0,60 + 0,06
non-alloy ≤ 1,60 + 0,10
normalized ≤ 1,70 – 0,05 / + 0,10
Mn thermomechanical formed ≤ 2,10 + 0,10
quenched and tempered ≤ 1,70 + 0,10
weather ≤ 1,50 – 0,05 / + 0,10
non-alloy ≤ 0,040 + 0,010
normalized / thermomechanical
P formed ≤ 0,030, + 0,005
quenched and tempered ≤ 0,025
weather ≤ 0,035 + 0,010
non-alloy ≤ 0,040 + 0,010
normalized/ thermomechanical
+ 0,005
formed ≤ 0,025
S
quenched and tempered ≤ 0,015 + 0,002
weather ≤ 0,035 + 0,010
Nb ≤ 0,060 + 0,010
V ≤ 0,20 + 0,02
≤ 0,03 + 0,01
Ti
> 0,03 + 0,02
≤ 0,30 + 0,05
Cr
> 0,30 + 0,10
≤ 0,80 + 0,05
Ni
> 0,80 + 0,10
Permissible deviation of the
Permissible maximum content in product analysis from
Element
the cast analysis specified limits for the cast
analysis
% by mass % by mass
≤ 0,10 + 0,03
Mo
> 0,10 + 0,04
non-alloy,
normalized/thermomechanical ±0,04
formed, weather ≤ 0,35
Cu non-alloy,
normalized/thermomechanical + 0,07
formed, weather 0,35 < Cu ≤ 0,55
quenched and tempered ≤ 0,50 + 0,05
non-alloy,
normalized/thermomechanical + 0,002
N
formed, weather ≤ 0,025
quenched and tempered ≤ 0,020 + 0,001
Al
≥ 0,020 – 0,005
total
B ≤ 0,005 0 + 0,000 5
Zr ≤ 0,15 + 0,02
7.2 Mechanical properties
7.2.1 Under the inspection and testing conditions as specified in Clause 8 and in the delivery condition
as specified in 6.5 the mechanical properties of the finished hollow section shall conform to the relevant
requirements of Tables A.3, B.3, B.4, C.3, C.4, D.3, D.4 and E.3.
Any heat treatment at more than 580 °C may lead to a reduction in the mechanical properties of TMCR
sections and also hot finished sections not processed in the normalizing temperature range.
The following option can be specified by the purchaser at the time of enquiry and order:
Option 1.5 longitudinal test pieces for the tensile test shall be taken from the centre of the corner,
but remote from the weld in welded sections, (see Annex F).
7.2.2 Another temperature as given in the Tables A.3, B.4, C.4, D.4 and E.3 may be agreed at the time of
the order.
If a Charpy test is performed at a lower temperature than specified in the standard and the impact energy
values obtained meet the requirements at the higher temperature, then the material is deemed to
conform to the standard and the test need not be repeated at the higher temperature.
The following option can be specified by the purchaser at the time of enquiry and order:
Option 1.6 longitudinal test pieces for the impact test shall be taken from the centre of the corner
with the notch orientated through the material thickness.
7.2.3 Subject to limitations of 7.2.2:
a) the impact properties of structural hollow sections of steel qualities J2, K2, N, NL, M, ML, Q, QL and
QL1 shall be verified;
b) the impact properties of structural hollow sections of steel qualities JR and J0 need not be verified
unless option 1.7 is specified by the purchaser at the time of enquiry and order.
Option 1.7 For products in qualities JR and J0 supplied with specific inspection and testing (see
Option 1.12 and 1.13) the verification of the impact properties is specified.
7.2.4 The following requirement for fine grain steel hollow sections can be specified.
For fine grain steel hollow sections in thicknesses which do not permit impact test pieces of width ≥ 5 mm
to be taken, the ferritic grain size (see 6.3) shall be verified by the method as described in EN ISO 643.
When aluminium is used as the grain refining element, the grain size requirement shall be deemed to be
fulfilled if the cast analysis shows the aluminium content to be ≥ than 0,020 % total aluminium or
alternatively ≥ 0,015 % soluble aluminium. In these cases, verification of the grain size is not required.
7.3 Technological properties
7.3.1 Weldability
The steels specified in this document are weldable as given in Annexes A to E. The general requirements
for welding of the products in accordance with this document shall comply with EN 1011-1 and
EN 1011-2.
NOTE 1 When welding hollow sections, as product thickness, strength level and CEV increase, the occurrence of
cold cracking in the welded zone forms the main risk. Cold cracking is caused by a combination of the following
factors:
— high levels of diffusible hydrogen in the weld metal;
— a brittle structure in the heat affected zone;
— significant tensile stress concentrations in the welded joint.
NOTE 2 By using guidelines, specified for example in EN 1011-1, EN 1011-2 or any other relevant welding
standard, the welding conditions and the various welding ranges for the steel grades can be determined. These will
vary depending on the product thickness, the applied welding energy, the design requirements, the electrode
efficiency, the welding process and the weld metal properties.
7.3.2 Hot-dip-zinc coating
EN ISO 1461 shall be used to specify coating requirements. EN ISO 14713-2 provides further guidance,
including information on the influence of various factors, including steel chemical composition, on the
coating formation.
Option 1.8 can be used to order steels with a chemical composition required for hot-dip-zinc coating.
When Option 1.8 is implemented, the purchaser and manufacturer shall agree a steel composition (cast
analysis) of silicon and phosphorous according to either
— Category A (see also EN ISO 14713-2:2020, Table 1, Note 1); or
— Category B; or
— Category D (limited to 0,25 % < Si ≤ 0,35 %)
with required values as cited by the ranges given in EN ISO 14713-2:2020, Table 1, column 2.
Option 1.8 The chemical composition shall be suitable for hot dip zinc coating. If no additional
information is given the delivered category is at the discretion of the manufacturer.
NOTE EN ISO 14713-2:2020, Tables 1 gives guidance on typical coating characteristics on the basis of the
surface composition of silicon and phosphorous associated with certain steel compositions.
The maximum carbon equivalent shall be increased by 0,02 or by 0,01 (see 7.1.3).
7.4 Product supply condition
7.4.1 The hollow sections shall have a smooth surface corresponding to the manufacturing method
used; bumps, cavities or shallow longitudinal grooves resulting from the manufacturing process are
permissible, provided the thickness is within tolerance, see EN 10210-2.
Surface imperfections may be removed by the manufacturer by grinding, provided that the thickness of
the hollow section after the repair is not less than the minimum permissible thickness in accordance with
EN 10210-2.
The p
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