SIST EN 50064:2019

SLOVENSKI STANDARD
SIST EN 50064:2019
01-januar-2019
1DGRPHãþD
SIST EN 50064:1998
SIST EN 50064:1998/A1:1998
Visokonapetostne stikalne in krmilne naprave - S plinom polnjena ohišja iz
gnetljivega aluminija in aluminijevih zlitin
High-voltage switchgear and controlgear - Gas-filled wrought aluminium and aluminium
alloy enclosures
Hochspannungs-Schaltgeräte und Schaltanlagen - Gasgefüllte Kapselungen aus
Aluminium und Aluminium-Knetlegierungen
Appareillage électrique haute tension - Enveloppes sous pression en aluminium corroyé
et en alliage d’aluminium
Ta slovenski standard je istoveten z: EN 50064:2018
ICS:
29.130.10 Visokonapetostne stikalne in High voltage switchgear and
krmilne naprave controlgear
77.150.10 Aluminijski izdelki Aluminium products
SIST EN 50064:2019 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50064:2019

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SIST EN 50064:2019

EUROPEAN STANDARD EN 50064

NORME EUROPÉENNE

EUROPÄISCHE NORM
November 2018
ICS 29.130.10 Supersedes EN 50064:1989
English Version
High-voltage switchgear and controlgear - Gas-filled wrought
aluminium and aluminium alloy enclosures
Appareillage électrique haute tension - Enveloppes sous Hochspannungs-Schaltgeräte und Schaltanlagen -
pression en aluminium corroyé et en alliage d'aluminium Gasgefüllte Kapselungen aus Aluminium und Aluminium-
Knetlegierungen
This European Standard was approved by CENELEC on 2018-08-27. CENELEC 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 CENELEC 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 CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.



European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
 Ref. No. EN 50064:2018 E

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SIST EN 50064:2019
EN 50064:2018 (E)
Contents Page
European foreword .4
Introduction .5
1 Scope .6
2 Normative references .6
3 Terms and definitions .7
4 Quality assurance .9
5 Normal and special service conditions .9
6 Materials . 10
6.1 Selection of material. 10
6.2 Chemical analysis. 11
7 Design . 11
7.1 General . 11
7.2 Calculation methods . 12
7.2.1 General . 12
7.2.2 Evaluation of mechanical strength using “Design by Formula” . 12
7.2.3 Evaluation of mechanical strength using “Design by Analysis” . 13
7.2.4 Evaluation of mechanical strength using “Design by Burst test” . 14
7.2.5 Flanges . 15
7.2.6 Bolted connections . 15
7.3 Inspection and access openings . 16
8 Manufacture and workmanship . 16
8.1 Material identification . 16
8.2 Order of completion of weld seams . 16
8.3 Cutting of materials . 16
8.3.1 General . 16
8.3.2 Cold sharing . 16
8.3.3 Thermal cutting . 17
8.3.4 Examination of cut edges . 17
8.4 Forming of shell sections and end plates . 17
8.5 Assembly tolerances . 17
8.6 Welded joints . 17
8.7 Assembly for welding. 17
8.8 General welding requirements . 17
8.9 Preheating . 18
8.10 Surface finish . 18
9 Repair of welding defects . 18
10 Inspection, testing and certification . 19
10.1 Type tests . 19
10.1.1 General . 19
10.1.2 Burst test procedure . 19
10.1.3 Strain measurement test . 19
10.2 Inspection and routine tests . 19
10.2.1 General . 19
10.2.2 Routine pressure tests . 20
10.3 Welding procedure specifications . 20
10.4 Welder performance tests . 20
10.5 Non-destructive testing . 20
10.5.1 Amount of testing of welded joints . 20
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10.5.2 Test methods for weld seams . 21
10.5.3 Surface conditions and preparations for testing . 21
10.5.4 Marking of the enclosure welds . 22
10.5.5 Reporting . 22
10.5.6 Minimum acceptance levels . 22
10.5.7 Assessment of imperfections . 22
10.6 Design specification, drawings and data sheets . 24
10.7 Certificate . 24
10.8 Stamping . 24
10.9 Final inspection . 24
11 Pressure relief devices . 25
11.1 General . 25
11.2 Bursting discs . 25
11.3 Self-closing pressure relief valves . 25
11.4 Non-self-closing pressure relief devices . 25
Annex A (informative) A-deviation . 27
Bibliography . 28

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SIST EN 50064:2019
EN 50064:2018 (E)
European foreword
This document (EN 50064:2018) has been prepared by CLC/TC 17AC, “High-voltage switchgear and
controlgear”.
The following dates are fixed:
• latest date by which this document has (dop) 2019-08-27
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2021-08-27
standards conflicting with this document
have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 50064:1989.
This European Standard has been revised by CENELEC Technical Committee 17AC High-voltage
switchgear and controlgear. It supplements the relevant product standards on gas-insulated switchgear and
controlgear in that it provides specific requirements for pressurized high-voltage switchgear and controlgear.
The present EN has been written to get a European specification for the design, construction, testing,
inspection and certification of pressurized enclosures used in high-voltage switchgear and controlgear.
In this respect this European Standard constitutes the exclusion of HV switchgear from the scope of the
Directive 2014/68/EU (superseding 97/23/EC) concerning pressure equipment. Article 1, 2. (l) excludes
“enclosures for high-voltage electrical equipment such as switchgear, controlgear, transformers, and rotating
machines” from the scope of the Directive.
This standard deals with gas-insulated switchgear enclosures of wrought aluminium and aluminium alloy and
their welding. For different enclosure materials, other European Standards are available.
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Introduction
This standard covers the requirements for the design, construction, testing, inspection and certification of
gas-filled enclosures for use specifically in high-voltage switchgear and controlgear, or for associated gas-
filled equipment.
Special consideration is given to these enclosures for the following reasons.
(a) The enclosures usually form the containment of electrical equipment, thus their shape is determined by
electrical rather than mechanical requirements.
(b) The enclosures are installed in restricted access areas and the equipment is operated by instructed,
authorized persons only.
(c) As the thorough drying of the inert, non-corrosive gas-filling medium is fundamental to the satisfactory
operation of the electrical equipment, the gas is periodically checked. For this reason, no internal corrosion
allowance is required on the wall thickness of these enclosures.
(d) The enclosures are subjected to only small fluctuations of pressure as the gas-filling density will be
maintained within close limits to ensure satisfactory insulating and arc-quenching properties. Therefore, the
enclosures are not liable to fatigue due to pressure cycling.
(e) The operating pressure is relatively low.
Due to the foregoing reasons and to ensure maximum service continuity as well as to reduce the risk of
moisture and dust entering the enclosures which may endanger safe electrical operation of the switchgear,
no pressure tests should be carried out after installation and before placing in service and no periodic
inspection of the enclosure interiors or pressure tests should be carried out after the equipment is placed in
service.
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SIST EN 50064:2019
EN 50064:2018 (E)
1 Scope
This document applies to wrought aluminium and aluminium alloy enclosures and their welding. These
enclosures are pressurized with dry air, inert gases, for example sulphur hexafluoride or nitrogen or a
mixture of such gases, used in indoor and outdoor installations of high-voltage switchgear and controlgear
with rated voltages above 1 kV, where the gas is used principally for its dielectric and/or arc-quenching
properties with rated voltages.
— above 1 kV and up to and including 52 kV concerning gas-filled compartments with design pressure
higher than 300 kPa relative pressure (gauge);
— above 52 kV concerning all gas-filled compartments.
The enclosures comprise parts of electrical equipment not necessarily limited to the following examples:
— circuit-breakers;
— switch-disconnectors;
— disconnectors;
— earthing switches;
— current transformers;
— voltage transformers;
— surge arrestors;
— busbars and connections;
— etc.
The scope also covers enclosures of pressurized components such as the centre chamber of live tank
switchgear, gas-insulated current transformers, etc.
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 13445-3, Unfired pressure vessels — Part 3: Design
EN 13445-8:2014, Unfired pressure vessels — Part 8: Additional requirements for pressure vessels of
aluminium and aluminium alloys
EN 62271-1:2017, High-voltage switchgear and controlgear — Part 1: Common specifications for alternating
current switchgear and controlgear (IEC 62271-1:2017)
EN ISO 3452 (all parts), Non-destructive testing — Penetrant testing (ISO 3452)
EN ISO 898 (all parts), Mechanical properties of fasteners made of carbon steel and alloy steel (ISO 898)
EN ISO 9606-2, Qualification test of welders — Fusion welding — Part 2: Aluminium and aluminium alloys
(ISO 9606-2)
EN ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel (ISO 9712)
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EN ISO 15614-2, Specification and qualification of welding procedures for metallic materials — Welding
procedure test — Part 2: Arc welding of aluminium and its alloys (ISO 15614-2)
EN ISO 17636 (all parts), Non-destructive testing of welds — Radiographic testing (ISO 17636)
EN ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and
assessment (ISO 17640)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
enclosure
part of gas-insulated metal-enclosed switchgear retaining the insulating gas under the prescribed conditions
necessary to maintain safely the rated insulation level, protecting the equipment against external influences
and providing a high degree of protection to personnel
3.2
manufacturer
organization that is responsible for the design of the enclosure and the production of the gas-insulated
switchgear
Note 1 to entry: In this standard, this is the switchgear manufacturer.
3.3
design pressure
pressure, expressed in relative terms (gauge), used to determine the thickness of the enclosure
Note 1 to entry: It is at least equal to the maximum pressure in the enclosure at the highest temperature that the gas
used for insulation can reach under specified maximum service conditions.
3.4
design temperature (of an enclosure)
maximum temperature that the enclosures can reach under specified maximum service conditions
Note 1 to entry: This is generally the upper limit of ambient air temperature increased by the temperature rise due to
the flow of rated normal current.
Note 2 to entry: Solar radiation should be taken into account when it has a significant effect on the temperature of the
gas and on the mechanical properties of materials. Similarly, the effects of low temperatures on the properties of some
materials should be considered.
[SOURCE: EN 62271-203:2012, 3.112, modified – Note 1 to entry and Note 2 to entry have been added]
3.5
design stress
maximum permissible stress on the enclosure imposed by conditions of operation, environment or test that
determine the (material) characteristics of an enclosure
3.6
normal load
load whose occurrence and level can be planned or predicted
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3.7
exceptional load
load whose probability of occurrence during the lifetime of product is very small or accidental
3.8
alloy
substance having metallic properties and composed of two or more elements so combined that they cannot
readily be separated by physical means
[SOURCE: EN 12258-1:2012, 2.2.1]
3.9
aluminium alloy
metallic substance in which aluminium predominates by mass and the other elements exceed 1% of the total
content by weight
3.10
weld defect
imperfections in metallic fusion welds
3.10.1
lack of fusion
lack of union between the weld metal and the parent material or between the successive layers of weld metal
[SOURCE: EN ISO 6520-1:2007, Reference No. 401]
3.10.2
overlap
excessive weld metal covering the parent material surface but not fused to it
[SOURCE: EN ISO 6520-1:2007, Reference No. 506]
3.10.3
undercut
irregular groove at a toe of a run in the parent material or in previously deposited weld metal
[SOURCE: EN ISO 6520-1:2007, Reference No. 5011]
3.10.4
hot crack (hot tear)
crack formed in a cast metal or in a welding because of internal stress developed upon cooling at the solidus
temperature or slightly above
[SOURCE: EN 12258-1:2012, 5.2.8]
3.10.5
inclusion
extraneous material accidentally entrapped into the liquid metal during melting or melt treatment or
entrapped into the metal surface during hot or cold working
[SOURCE: EN 12258-1:2012, 5.5.7]
3.10.6
blister
raised spot whose inside is hollow, that forms on the surface of products and is caused by the penetration of
a gas into a subsurface zone typically during thermal treatment
[SOURCE: EN 12258-1:2012, 5.5.10]
Note 1 to entry: A void resulting from blister that has ruptured is often termed “blow hole”.
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3.11
thermal treatment
heating, holding at elevated temperature and cooling of the solid metal in such a way as to obtain desired
metallurgical structure or properties
[SOURCE: EN 12258-1:2012, 3.6.1]
Note 1 to entry: The term “heat treatment” is used for the same concept as a synonym.
3.12
ductility
ability of a material to deform plastically before fracturing
[SOURCE: EN 12258-1:2012, 4.3.15]
3.13
fatigue
tendency for a metal to break under conditions of repeated cyclic stressing considerably below the tensile
strength
[SOURCE: EN 12258-1:2012, 4.3.23, modified – Note 1 to entry has been removed]
3.14
tensile strength
ratio of maximum load before rupture in a tensile test to original cross-sectional area
[SOURCE: EN 12258-1:2012, 4.3.3]
3.15
yield strength
stress necessary to produce a defined small plastic deformation in a material under uniaxial tensile or
compressive load
[SOURCE: EN 12258-1:2012, 4.3.4, modified]
3.16
test piece
two or more parts of material welded together in accordance with a specified weld procedure, in order to
make one or more test specimens
3.17
test specimen
portion detached from a test piece, in specified dimensions, finally prepared as required for testing
4 Quality assurance
It is the intention of this standard that the switchgear manufacturer shall be responsible for achieving and
maintaining a consistent and adequate quality of the product.
Sufficient examinations shall be made by the enclosure manufacturer to ensure that the materials,
production and testing comply in all respects with the requirements of this standard.
Inspection by the user`s inspectors shall not absolve the switchgear manufacturer from his responsibility to
exercise such quality assurance procedures as to ensure that the requirements and the intent of this
standard are satisfied.
5 Normal and special service conditions
Clause 2 of EN 62271-1:2017 is applicable.
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6 Materials
6.1 Selection of material
Any aluminium or aluminium alloy is permissible. A list of recommended materials is given in Table 1 based
on information from EN 13445-8:2014.
The elongation after fraction of any aluminium or aluminium alloy shall comply with EN 13445-8:2014, 5.2.
NOTE Contact with more noble metals, particularly copper and its alloys, can lead to heavy galvanic corrosion.
Austenitic stainless steel is an exception to this rule because of its protective oxide film and can often be used in contact
with aluminium.
Aluminium enclosures should be protected externally where, for example, they come into contact with mild
steel supports.
Bitumen, thin zinc sheet (which gives sacrificial protection) or a combination of these are useful in this
respect. Alternatively, the mild steel supports can be galvanized or zinc or aluminium sprayed.
It should be noted that contact with certain gasket materials can cause corrosion of aluminium. The gasket
manufacturer should be consulted.
Table 1 — List of recommended aluminium alloys [1]
Group Sub Type of aluminium Designation
and
Group
EN AW number Chemical symbol Temper
aluminium alloys
22 Non heat treatable alloys
 22.1 Aluminium-manganese EN AW — 3003 EN AW-Al Mn1Cu O, H111,
alloys H112
EN AW — 3103 EN AW-Al Mn1
O, H111,
EN AW — 3105 EN AW-Al Mn0,5Mg0,5
H112
O, H111
 22.2 Aluminium-magnesium EN AW — 5005 EN AW-Al Mg1(B) O, H111,
alloys with Mg ≤ 1,5 % H112
EN AW — 5005A EN AW-Al Mg1(C)
O, H111,
EN AW — 5050 EN AW-Al Mg1,5(C)
H112
O, H111
 22.3 Aluminium-magnesium EN AW — 5049 EN AW-Al Mg2Mn0,8 O, H111,
alloys with H112
EN AW — 5052 EN AW-Al Mg2,5
1,5 % < Mg ≤ 3,5 %
O, H111,
EN AW — 5154A EN AW-Al Mg3,5(A)
H112
EN AW — 5251 EN AW-Al Mg2
O, H111,
EN AW — 5454 EN AW-Al Mg3Mn(A)
H112
EN AW — 5754 EN AW-Al Mg3
O, H111,
H112
O, H111,
H112
O, H111,
H112
 22.4 Aluminium-magnesium EN AW — 5083 EN AW-Al Mg4,5Mn0,7 O, H111,
alloys with Mg > 3,5 % H112
EN AW — 5086 EN AW-Al Mg4
O, H111
23 Heat treatable alloys
a
 23.1 Aluminium-magnesium- EN AW — 6060 EN AW-Al MgSi T4
b c
silicon
EN AW — 6061 EN AW-Al Mg1SiCu T4 , T6
b c
alloys
EN AW — 6082 EN AW-Al Si1MgMn T4 , T6
a
For profiles only.
b
For seamless pipes and flanges only.
c
For flanges only.
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These alloys are recommended because of their low content of copper and zinc (lower than 0,5 % each) as
well as their low content of magnesium (lower than 0,7 %).
Alloys listed in this table are similar but not identical regarding chemical composition and mechanical
properties. They are not interchangeable without a re-qualification of the enclosure, i.e. re-calculation or re-
testing.
The properties of the materials should be taken from the applicable standards.
For applications where specified temperatures exceed 100 °C heat treated materials are not permitted due to
the loss of material properties, i.e. the thermal treatment will be nullified.
6.2 Chemical analysis
The chemical composition shall be in accordance with their material specification materials except that all
materials shall have a maximum lead content of 150 pg/g.
It is recommended that the material to be used for welded components be produced from rolling or extrusion
ingots with hydrogen level no greater than 0,2 ml per 100 g aluminium, measured on liquid metal during
casting.
Ingots used shall comply with the requirements of the appropriate material specification and any special
requirement called for on the order; they shall be clean and free from harmful defects.
Providing the chemical analysis of the melt meets the requirements of the appropriate specification, the
founder may use scrap which arises from his own production from approved ingots, which is segregated and
identifiable. It may include heavy fettling scrap, but shall exclude all drosses and small particles such as
sawings and chippings.
NOTE Attention is drawn to a limitation of the range of aluminium-magnesium alloys. Alloys with magnesium
content above 4 % can become susceptible to stress-corrosion cracking after use for long periods at temperatures above
100 °C.
7 Design
7.1 General
The rules for the design of enclosure
...