SIST ENV 1090-6:2001

S L O V E N S K I SIST ENV 1090-6
prva izdaja
PREDSTANDARD
julij 2001
Izdelava in montaža jeklenih konstrukcij – 6. del: Dopolnilna pravila za
nerjavna jekla (prevzet ENV 1090-6:2000 z metodo platnice)
Execution of steel structures - Part 6: Supplementary rules for stainless steel
Exécution des structures en acier - Partie 6: Règles supplémentaires pour les
aciers inoxydable
Ausführung von Tragwerken aus Stahl - Teil 6: Ergänzende Regeln für rostfreien
Stahl
Deskriptorji: jeklene konstrukcije, nerjavna jekla, materiali, izdelava, varjenje, stikovanje,
geometrijska odstopanja, zaščita, pregledi, preskusi
Referenčna številka
ICS 77.140.20; 91.080.10 SIST ENV 1090-6:2001 ((sl),en)
Nadaljevanje na straneh od II do IV in od 1 do 39
© Standard je založil in izdal Urad Republike Slovenije za meroslovje. Razmnoževanje ali kopiranje celote ali delov tega standarda ni
dovoljeno.

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SIST ENV 1090-6 : 2001
NACIONALNI UVOD
Predstandard SIST ENV 1090-6 ((sl),en), Izdelava in montaža jeklenih konstrukcij - 6. del: Dopolnilna
pravila za nerjavna jekla, prva izdaja, 2001, ima status slovenskega predstandarda in je z metodo
platnice prevzet evropski predstandard ENV 1090-6 (en), Execution of steel structures - Part 6:
Supplementary rules for stainless steel, January 2000.
NACIONALNI PREDGOVOR
Evropski predstandard ENV 1090-6:2000 je pripravil tehnični odbor Evropskega komiteja za
standardizacijo CEN/TC 135 Izdelava in montaža jeklenih konstrukcij.
Odločitev za prevzem tega predstandarda po metodi platnice je sprejela delovna skupina USM/TC
KON/WG 3 Jeklene konstrukcije, ki je pripravila tudi nacionalni dokument za uporabo v Sloveniji,
potrdil pa tehnični odbor USM/TC KON Konstrukcije.
Ta slovenski predstandard se lahko uporablja samo v skladu z nacionalnim dokumentom, ki je
sestavni del SIST ENV 1090-6:2001.
Ta slovenski predstandard je dne 2000-12-04 odobril direktor USM.
Rok veljavnosti tega predstandarda je do izdaje evropskega standarda EN 1090-6.
ZVEZE S STANDARDI
S prevzemom tega evropskega predstandarda veljajo za naslednje zveze:
SIST ENV 1090-1:1999 ((sl),en) Izdelava in montaža jeklenih konstrukcij – 1. del: Splošna
pravila in pravila za stavbe
SIST ENV 1992-1-1:1999 ((sl),en) Eurocode 2: Projektiranje betonskih konstrukcij – Del 1-1:
Splošna pravila in pravila za stavbe
SIST ENV 1993-1-1:1996 ((sl),en) Eurocode 3: Projektiranje jeklenih konstrukcij -
Del 1-1: Splošna pravila in pravila za stavbe
SIST ENV 1993-1-4:2001 ((sl),en) Eurocode 3: Projektiranje jeklenih konstrukcij – Del 1-4:
Splošna pravila – Dopolnilna pravila za nerjavna jekla
SIST ENV 1994-1-1:1998 ((sl),en) Eurocode 4: Projektiranje sovprežnih konstrukcij – Del 1-1:
Splošna pravila in pravila za stavbe
OPOMBI
- Povsod, kjer se v besedilu predstandarda uporablja izraz “evropski predstandard”, v
SIST ENV 1090-6:2001 to pomeni “slovenski predstandard”.
- Nacionalni uvod in nacionalni predgovor nista sestavni del predstandarda.
II

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SIST ENV 1090-6 : 2001
VSEBINA Stran
Nacionalni dokument za uporabo v Sloveniji. IV
ENV 1090-6:2000 .1
III

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SIST ENV 1090-6 : 2001
Nacionalni dokument za uporabo v Sloveniji
Pri referenčnih standardih za vijake je potrebno upoštevati določila Nacionalnega dokumenta za
uporabo v Sloveniji za SIST ENV 1090-1:1999.
IV

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EUROPEAN PRESTANDARD
ENV 1090-6
PRÉNORME EUROPÉENNE
EUROPÄISCHE VORNORM
January 2000
ICS 77.140.20; 91.080.10
English version
Execution of steel structures - Part 6: Supplementary rules for
stainless steel
Exécution des structures en acier - Partie 6: Règles Ausführung von Tragwerken aus Stahl - Teil 6: Ergänzende
supplémentaires pour les aciers inoxydable Regeln für rostfreien Stahl
This European Prestandard (ENV) was approved by CEN on 11 April 1999 as a prospective standard for provisional application.
The period of validity of this ENV is limited initially to three years. After two years the members of CEN will be requested to submit their
comments, particularly on the question whether the ENV can be converted into a European Standard.
CEN members are required to announce the existence of this ENV in the same way as for an EN and to make the ENV available promptly
at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the ENV) until the final
decision about the possible conversion of the ENV into an EN is reached.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Central Secretariat: rue de Stassart, 36  B-1050 Brussels
© 2000 CEN All rights of exploitation in any form and by any means reserved Ref. No. ENV 1090-6:2000 E
worldwide for CEN national Members.

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ENV 1090-6:2000
CONTENTS
FOREWORD 4
INTRODUCTION 4
1SCOPE 4
2 NORMATIVE REFERENCES 5
3 DEFINITIONS 7
4 DOCUMENTATION 7
5 MATERIALS 7
5.1 General 7
5.2 Use of materials 8
5.3 Welding consumables 9
5.4 Mechanical fasteners 9
5.6 Bolts with locking devices 11
6 FABRICATION 11
6.2 Identification 11
6.3 Handling and storage 11
6.4 Cutting 12
6.5 Shaping 12
6.6 Holing 13
7 WELDING 13
7.101 General 13
7.102 Modifications to EN 1011-1 requirements 14
7.103 Modifications to prEN 1011-3 requirements 14
7.104 Other welding processes 15
7.105 Other weld types 16
7.106 Welding different stainless steels to each other or to other metallic materials 16
8 MECHANICAL FASTENING 16
8.1 General 16
8.2 Hole sizes and positions 16
8.5 Use of washers 17
8.6 Tightening of non-preloaded bolts 17
8.7 Tightening of preloaded bolts 17
8.8 Contact surfaces in slip resistant connections 17
8.9 Use of special fasteners and fastening methods 18
8.112 Fastening sidelaps 18
8.113 Galling and seizure 18
9 ERECTION 19
9.5 Workmanship 19
9.106 Cleaning 19

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ENV 1090-6:2000
10 PROTECTIVE TREATMENT 20
10.1 General 20
10.2 Surface preparation 20
10.3 Coating Methods 20
10.5  Treatment of fasteners 20
11 GEOMETRICAL TOLERANCES 20
11.1 General 20
11.2 Fabrication tolerances 20
12 INSPECTION, TESTING AND CORRECTIONS 24
12.1 General 24
12.2 Materials and fabricated products 25
12.3 Fabrication 25
12.4 Welding 25
12.5 Mechanical fastening 26
12.6 Protective treatment 26
12.7 Erection 27
12.108 Surface condition 27
ANNEX A  (Normative) PROCEDURE TESTS FOR PRELOADING BOLTS AND
DETERMINATION OF SLIP FACTOR 28
ANNEX B  (Normative) RIVETING 28
ANNEX C  (Informative) PROJECT SPECIFICATION 29
ANNEX D  (Informative) CLASSIFICATION OF FABRICATED STEEL COMPONENTS
AND SYSTEMS FOR THE CONTROL OF CONFORMITY 32
ANNEX E  (Informative) GUIDELINES FOR WELDING COORDINATION 33
ANNEX F  (Informative) HEXAGON INJECTION BOLTS 34
ANNEX G  (Informative) GUIDELINES FOR INSPECTION AND TEST PLAN 35
ANNEX H  (Informative) GUIDELINES FOR WELD IMPERFECTION LIMITS 36
ANNEX J  (Informative) SELECTION AND USE OF MECHANICAL
FASTENERS FOR SHEETING 37
Annex L (Informative) GUIDANCE FOR BENDING OF CIRCULAR TUBES 39
Annex M (Informative) BIBLIOGRAPHY 40

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ENV 1090-6:2000
FOREWORD
This European Prestandard has been prepared by Technical Committee CEN/TC 135 "Execution of
steel structures and aluminium structures", the secretariat of which is held by NSF.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to announce this European Prestandard: Austria, Belgium, Czech
Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg,
Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom.
INTRODUCTION
Addition:
(104) This European Prestandard ENV 1090-6 is a supplement to ENV 1090-1: Execution of Steel
Structures - General rules and rules for buildings and specifies particular requirements for the
execution of stainless steel structures designed to ENV 1993-1-4.
(105) This European Prestandard presupposes that the work is performed in accordance with the
requirements of ENV 1090-1, as varied by this supplement.
(106) In this European Prestandard, the following terms are used:
  Addition: means that the text applies in addition to the corresponding clause or subclause
of ENV 1090-1 without any amendments to the existing text of ENV 1090-1;
  Modification: means that the text shall modify the corresponding text of ENV 1090-1 as
appropriate.
(107) An addition is identified by the subsequent number to the last subclause respective paragraph
number of ENV 1090-1 added to 100.
(108) If a sub-clause of ENV 1090-1 is not mentioned in this ENV 1090-6 that sub-clause shall apply.
(109) The supplementary rules of ENV 1090-3 do not apply to stainless steels.
(110) The supplementary rules of ENV 1090-4 apply to hollow section lattice structures executed
using stainless steel.
1SCOPE
Modification:
(1) This Part 6 of European Prestandard ENV 1090 specifies requirements for execution of structural
steelwork produced from stainless steel products.
(2) This Part of ENV 1090 gives detailed requirements for structures that are not significantly
susceptible to fatigue. The definition of structures which are not significantly susceptible to fatigue is
given in ENV 1993-1-1.
Addition:
(106) This Part of ENV 1090 applies to austenitic and austenitic-ferritic stainless steels. In addition,
non-welded threaded bars of precipitation hardened stainless steel are covered. It does not apply to
ferritic type stainless steels.

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ENV 1090-6:2000
NOTE: It is expected that a later version of this Part of ENV 1090 will contain appropriate
provisions for other stainless steels.
(107) This standard gives details of surface finish specification requirements.
2 NORMATIVE REFERENCES
This clause of ENV 1090-1 is applicable except as follows
Addition:
prEN 508-3 Roofing products from metal sheet - Specification for self-supporting
products of steel, aluminium or stainless steel sheet –
Part 3: Stainless steel
EN 571-1 Non-destructive testing - Penetrant testing – Part 1: General principles
EN 970:1997 Non-destructive examination of fusion welding - Visual examination
EN 1011-1:1998 Requirements for fusion welding of metallic materials  Part 1: General
prEN 1011-3 Requirements for fusion welding of metallic materials
Part 3: Stainless steels
ENV 1090-1:1996 Execution of steel structures - Part 1: General rules and rules for buildings
ENV 1090-2:1998 Execution of steel structures - Part 2: Supplementary rules for cold formed
thin gauge components and sheeting
ENV 1090-3:1997 Execution of steel structures –
Part 3: Supplementary rules for high yield strength steels
ENV 1090-4:1997 Execution of steel structures -
Part 4: Supplementary rules for hollow section lattice structures
EN 1435:1997 Non-destructive examination of welds - Radiographic examination of
welded joints
prEN 1711: Non-destructive examination of welds – Eddy current examination by phase
discrimination method
ENV 1993-1-3:1992 Eurocode 3: Design of steel structures -
Part 1-3: General rules - Supplementary rules for cold formed thin gauge
members and sheeting
ENV 1993-1-4:1996 Eurocode 3: Design of steel structures -
Part 1-4: General rules - Supplementary rules for stainless steels
EN-ISO 3506-1:1997 Mechanical properties of corrosion-resistant stainless-steel fasteners –
Part 1: Bolts, screws and studs
EN-ISO 3506-2:1997 Mechanical properties of corrosion-resistant stainless-steel fasteners –
Part 2: Nuts
EN-ISO 3506-3:1997 Mechanical properties of corrosion-resistant stainless-steel fasteners –
Part 3: Set screws and similar fasteners not under tensile stress
prEN 10028-7 Flat products made of steels for pressure purposes - Stainless steels

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ENV 1090-6:2000
EN 10048:1997 Tolerances on dimensions and shape for hot rolled narrow steel strip
EN 10088-2:1995 Stainless steel - Part 2: Technical delivery conditions for steel/plate and
strip for general purposes
EN 10088-3:1995 Stainless steel - Part 3: Technical delivery conditions for semi-finished
products, bars, rods and sections for general purposes
prEN 10162 Cold rolled sections - Technical delivery conditions, dimensional and
cross-sectional tolerances
prEN 10216-5 Seamless steel tubes for pressure purposes - technical delivery conditions
Part 5: Stainless steels
prEN 10217-7 Welded steel tubes for pressure purposes - technical delivery conditions
Part 7: Stainless steels
EN 10258:1997 Cold rolled stainless steel and narrow strip and cut lengths - Tolerances on
dimension and shape
EN 10259:1997 Cold rolled stainless and heat-resisting steel wide strip and plate/sheet –
tolerances on dimension and shape
prEN 10272 Hot rolled stainless steel bar for pressure purposes
EN 12062:1997 Non-destructive examination of welds – General rules for metallic materials
EN-ISO 14555:1999 Welding – Arc stud welding of metallic materials
prEN-ISO 15620 Welding – Friction welding of metallic materials
EURONORM 17 (1970) Wire rod in general purpose non-alloy steel for cold drawing or forming;
tolerances, dimensions
EURONORM 58 (1978) Hot rolled flats for general purposes
EURONORM 59 (1978) Hot rolled square bars for general purposes
EURONORM 60 (1977) Hot rolled round bars for general purposes
EURONORM 61 (1982) Hot rolled hexagons
EURONORM 65 (1980) Hot rolled round bars for screws and rivets
ISO 1127:1997 Stainless steel tubes - Dimensions, tolerances and conventional masses
per unit length
ISO 3269:1988 Fasteners - Acceptance inspection

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ENV 1090-6:2000
3 DEFINITIONS
This clause of ENV 1090-1 is applicable except as follows:
3.118: cold forming: The process of forming steel sheet or strip into a component with
open or closed cross section, or into a profiled sheet, by either roll
forming, pressing or folding.
3.119: construction classes: See ENV 1993-1-3
3.120: fabrication: All activities performed to produce finished steel components
including cold formed thin gauge components and sheeting ready
for assembly on site.
3.121: fabrication tolerance: Permitted variation in the size of a dimension of a component
resulting from component manufacture
3.122: structural sheeting: Profiled steel sheets produced by cold-forming and used in such a
manner as to form either:
a) a stressed skin shear diaphragm;
b) a bracing system offering structural restraint to other
components or assemblies of components;
c) part of a cladding system intended to offer access to roofs for
the purpose of maintenance and repair.
3.123: thin gauge components: Open or closed section structural components with a cross section
bounded by either free edges or by bends produced by cold
forming sheet or strip steel.
NOTE: Hollow section components may be made either:
a) by joining two previously formed open sections by continuous
welding; or
b) from a single flat strip by forming the corners to make a box and
continuously welding the longitudinal seam. The flat strip may also
be work hardened before forming as stated in the project
specification.
NOTE: The definitions 3.118, 3.119, 3.120, 3.122 and 3.123 are
identical to the definitions in ENV 1090-2.
4 DOCUMENTATION
This clause of ENV 1090-1 is applicable.
5MATERIALS
This clause of ENV 1090-1 is applicable except as follows:
5.1 General
Addition:
(106) The project specification shall specify stainless steel material to be used in the works in terms
of the relevant product standard from Table 1. If products not covered by standards are used
they shall be specified in the project specification.

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ENV 1090-6:2000
NOTE: Table 1 gives information on the product standards for stainless steel. Grades and
finishes should be stated in the project specification together with any options allowed by the
product standard.
(107) The project specification shall specify the requirements for corrosion resistance and mechanical
properties of connectors and fasteners. Unless otherwise specified, the connectors or fasteners shall
be at least as corrosion resistant as the connected parts.
(108) The surface finish requirements of the stainless steel shall be specified in the project
specification. The surface finish of:
- Sheet, plate and strip shall be in accordance with the requirements of EN 10088-2
- Bars, rods and sections shall be in accordance with the requirements of EN 10088-3
- Other product forms shall be specified in terms of appropriate national and international
specifications.
If the relevant specification does not adequately define decorative or specialist surface finishes, the
finish shall be detailed in the project specification.
Modification of Table 1 of ENV 1090-1: Product standards for stainless steel materials
Products Technical delivery requirements Tolerances
General Pressure
engineering retaining
Sheet, plate and strip EN 10088-2 prEN 10028-7 EN 10029
EN 10048
EN 10051
EN 10258
EN 10259
Tubes (welded) prEN 100xx prEN 10217-7
ISO 1127
Tubes (seamless) prEN 100yy prEN 10216-5
Hollow sections prEN 100zz - ISO 1127
Bars, rods and sections EN 10088-3 prEN 10272 Eu 17, Eu 58, Eu 59,
Eu 60, Eu 61, Eu 65
5.2 Use of materials
5.2.1 Identification
Addition to Note:
Where studding other than property class 50 (EN ISO 3506-1) is being used care should be taken to
ensure that it is identifiable at all stages from receipt to handover after incorporation in the works.
5.2.2 Handling and storage
Addition:
(104) Stainless steel shall not be contaminated by fixtures or manipulators etc.

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ENV 1090-6:2000
5.2.3 Steel for welded components
This clause is not applicable.
NOTE: Guidance for welded components of stainless steels are given in prEN 1011-3.
5.2.4 Special properties
Modification:
(1) The project specification shall specify any special restrictions on either surface discontinuities or the
repair of surface defects by grinding in accordance with EN 10088-2 or EN 10088-3.
(2) and (3) are not applicable
Addition:
(104) Any special requirements, for example Pitting Resistance Equivalent (Nitrogen) (PRE(N)) or
accelerated corrosion testing, shall be specified in the project specification. The PRE(N) shall be given
by (Cr + 3.3 Mo + 16N), in which the elements are in weight percent, unless otherwise specified.
O
(105) Welded connections shall not be used in service at temperatures over 375 C unless permitted
by the project specification.
5.3 Welding consumables
(3) is not applicable.
Addition:
(104) Consumables shall be used which give weld deposits of at least equivalent corrosion resistance
to the parent metal. All consumables shall be kept free from contaminants, and stored according to
the manufacturer's instructions.
5.4 Mechanical fasteners
5.4.1 Hexagon bolts, screws, hexagon nuts, studs and plain washers
5.4.1.2Mechanical properties
Addition:
(105) The mechanical properties of austenitic stainless steel bolts, screws, nuts and studs up to M39
for property class 50 and up to M24 for property classes 70 and 80 shall be in accordance with
EN-ISO 3506-1 and EN-ISO 3506-2.
(106) The mechanical properties of larger diameter austenitic bolts and austenitic-ferritic bolts at any
diameter shall be specified in the project specification.
(107) The mechanical properties of austenitic stainless steel washers up to M39 shall be as listed in
Table 2.
(108) The mechanical properties of larger diameter austenitic washers and austenitic-ferritic washers
at any diameter shall be specified in the project specification.

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ENV 1090-6:2000
5.4.1.3Bolt assemblies
Modification:
(1) Table 2 shall be replaced by table 2 below.
Modification of Table 2 of ENV 1090-1: Non-preloaded stainless steel bolt assemblies
Bolts Nuts Washers
Standard Class
1) 1)
EN 24014 EN 24032 ISO 7089 A 140
1)
EN 24017 ISO 7090 A 140
1)
NOTE: These standards make reference to stainless steel bolts and nuts to grade A2 only.
Grade A3, A4 and A5 bolts and nuts may be used if stated in the project specification.
(2) Stainless steel bolts shall not be used in preloaded applications unless stated in the project
specification. Table 3 is not applicable, and preloaded applications shall be treated as special
fasteners.
Addition:
(104) Stainless steel bolt assemblies shall comprise matching bolts, nuts and washers. Austenitic
stainless steel bolt assemblies up to M39 for property class 50 and up to M24 for property classes 70
and 80 shall conform with an appropriate combination given in Table 2.
(105) Appropriate combinations of matching bolts, nuts and washers for larger diameter austenitic
bolt assemblies and austenitic-ferritic bolts at any diameter shall be specified in the project
specification.
5.4.2 Direct tension indicating washers
This clause is not applicable.
5.4.3 Special fasteners
Addition:
(103) The following fasteners generally used for fastening in thin gauge members and sheeting shall
be treated as special fasteners:
- self tapping and self drilling fasteners;
- blind rivets;
- cartridge fired pins;
- air driven pins.
NOTE: Annex J gives guidance for selection of these mechanical fasteners.
(104) Special fasteners shall be delivered in appropriate durable packaging and labelled such that the
contents are readily identifiable.
NOTE: Labelling or supporting documentation should bear the following information in a legible
and durable form:
- manufacturer’s or supplier’s identification;
- type of fastener and, if appropriate, its assembly;
- fastener material and, if appropriate, protective coating;

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ENV 1090-6:2000
- dimensions in mm, as appropriate for nominal diameter, length, washer diameter and
thickness of elastomeric part, effective fastening range;
- size of drill bit as appropriate;
- for screws: method of preventing over-tightening;
- for cartridge fired and air driven pins: details of the firing charge and driving forces as
appropriate.
A drawing to the scale 1:1 with the appropriate notation is adequate to provide the dimensional
information.
(105) Unless stated in the project specification, special fastener assemblies shall bear a
manufacturer’s or supplier’s identification mark on the assembly that is recognizable after the fasteners
have been set.
5.6 Bolts with locking devices
Modification:
Note to (1) is not applicable.
6 FABRICATION
This clause of ENV 1090-1 is applicable except as follows:
6.2 Identification
Modification:
(2) Identification marks shall not be made by hard stamping and punching, unless soft stamps are
used. Chiselled notches shall not be used.
Addition:
(103) Identification may be achieved as appropriate by batching or by the shape or the size of the
component, or by the use of durable and distinguishing marks applied in a way not producing any
damage.
(104) The project specification shall define the identification requirements and any zones where
identification marks shall not be visible after completion.
NOTE: Identification may include rolling direction, sheet number or cast number.
6.3 Handling and storage
Addition to (1):
NOTE: Certain cold formed thin gauge members may be particularly prone to edge damage,
twisting and distortion if handled as individual items. Single point lifting of long components
should be avoided by the use of spreader beams as appropriate. If bundled together, nested
components may be robust, but care should be taken to avoid localized damage to unstiffened
edges at lifting points or other zones where the total weight of the bundle is imposed on a single
unreinforced edge.
Addition:
(103) All stainless steel shall be stored carefully, so that the surfaces are protected from damage or
contamination. If the use of a protective film is required, it shall be included in the project specification.
(104) The project specification shall specify which of the handling and storage procedures given in
Table 3 are applicable.

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ENV 1090-6:2000
Table 3: List of handling and storage measures
No Description
1 If the stainless steel has a protective plastic or other coating, it is left on as long as
practicable, and removed just before final fabrication or close-in.
2 Storage in salt-laden humid atmospheres is avoided.
3 Storage racks are protected by wooden, rubber or plastic battens or sheaths to avoid carbon
steel, copper-containing, lead etc. rubbing surfaces.
4 Markers containing chloride or sulphide are not used. An alternative is to use protective film
and apply all marks only into this film.
5 Stainless steel is protected from direct contact with carbon steel lifting tackle or handling
equipment such as chains, hooks, strapping and rollers or the forks of fork lift trucks by the
use of isolating materials or light plywood or suction cups. Appropriate erection tools are
used to ensure that surface contamination does not occur.
6 Contact with chemicals, including dyes, glues, adhesive tape, undue amounts of oil and
grease is avoided. If it is necessary to use them, their suitability is checked with their
manufacturer.
7 Segregated fabrication areas are used for carbon steel and stainless steel to prevent carbon
steel pick-up. Separate tools are dedicated for use with stainless steel only, particularly
grinding wheels and wire brushes. Wire brushes and wire wool are of stainless steel,
preferably an austenitic grade. Ferritic stainless steel brushes are not used on austenitic
stainless steels.
8 Special measures may be needed for protecting fabricated steelwork in transit.
6.4 Cutting
Modification:
(1) Cutting may be carried out by sawing, shearing, plasma arc, laser and water jet techniques. Oxy-
fuel cutting shall not be used for cutting stainless steels, unless a powder fluxing technique is used.
NOTE 1:Cutting (and machining in general) should be carried out when the metal is in the
annealed condition, in order to limit work hardening and consequent tool wear.
(2) and (5) are not applicable.
6.5 Shaping
Modification to the Note to (1):
NOTE: Cold forming processes are usually used. The power requirement for bending stainless
steel are higher than for bending geometrically similar carbon steel members, due to work
hardening (by about 50% in the case of the austenitic steels or even more in the case of 1.4462
austenitic-ferritic steel). Guidance for bending of circlar tubes are given in Annex L.
In order to counteract the effects of spring-back, stainless steel needs to be over-bent to a
slightly higher degree than carbon steel.
(2) For hot forming the recommendations (if any) of the steel producer shall be observed.
Modification:

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ENV 1090-6:2000
(4) If shaping by controlled application of heat is used to correct distortion, the maximum steel
temperature and the cooling procedure shall be carefully controlled. Procedures shall be specified in
the project specification.
Addition:
(106) Unless otherwise specified in the project specification, the minimum inside bend radii to be
formed shall be:
- 2t for austenitic grades 1.4301, 1.4401, 1.4404, 1.4541 and 1.4571;
-2,5t for austenitic-ferritic grade 1.4462.
in which t is the thickness of the material.
For other grades of stainless steel, the minimum inside bend radii shall be given in the project
specification.
NOTE: Smaller inside bend radii may be permitted if due consideration is given to issues such
as steel specification, condition and thickness and the direction of bending in relation to the
rolling direction.
(107) Lubricants shall be specified in the project specification.
6.6 Holing
Modification:
(1) This subclause applies to the making of holes for non-preloaded bolts only.
(2) Holes may be formed by drilling, punching, laser cutting or other methods permitted by the project
specification. The project specification shall define if reaming is to be used.
(3) Material up to 20 mm in thickness may be punched provided that the nominal thickness of the
material is not greater than the nominal diameter of the hole, or for a non-circular hole, its minimum
dimension.
NOTE: Punching material may lead to local cracking on shear lines.
Modification:
(5) Slotted holes shall be either punched in one operation or formed by drilling or punching two holes
and completed by thermal cutting, unless otherwise stated in the project specification.
7 WELDING
This clause of ENV 1090-1 is not applicable and is superseded by the following clause.
7.101 General
(1) The requirements for arc welding of stainless steels shall be in accordance with EN 1011-1 and
prEN 1011-3 as amended by sub-clauses 7.102 and 7.103 of this European standard.
(2) Where required by the project specification, a welding plan shall be drawn up to relate the welding
procedures and specific instructions to particular joints.
(3) The project specification shall state any specific requirements for application of EN 729-3.

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ENV 1090-6:2000
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