Aerospace series - Welded and brazed assemblies for aerospace construction - Joints of metallic materials by electron beam welding - Part 001: Quality of welded assemblies

This European Standard defines the rules to be satisfied to ensure the quality of joints of metallic materials by electron beam welding (reference number 51 according to EN ISO 4063). It applies unreservedly to the manufacturing of new parts or for repair, these operations being under the responsibility of an approved manufacturer or supplier. The final responsibility is with the design authority.

Luft- und Raumfahrt - Schweiß- und Lötverbindungen für die Luft- und Raumfahrt - Verbindungen metallischer Werkstoffe mittels Elektronenstrahlschweißen - Teil 001: Qualität der Schweißverbindungen

Diese Europäische Norm legt die zu erfüllenden Regeln fest, damit die Qualität der Verbindungen metallischer
Werkstoffe mittels Elektronenstrahlschweißen sichergestellt wird (Ordnungsnummer 51 nach EN ISO 4063).
Sie gilt vorbehaltlos für die Herstellung von neuen Teilen oder für die Reparatur; diese Verfahren liegen in der
Verantwortung eines anerkannten Herstellers oder Lieferers. Die abschließende Verantwortung liegt bei der
Konstruktionsstelle.

Série aérospatiale - Assemblages soudés et brasés pour constructions aérospatiales - Assemblages de matériaux métalliques soudés par faisceau d'électrons - Partie 001: Qualité des assemblages soudés

La présente Norme européenne définit les règles à observer pour garantir la qualité des constructions
aérospatiales en matériaux métalliques soudées par faisceau d’électrons (code 51 d'après la
NF EN ISO 4063).
Elle s'applique sans restriction pour la fabrication de pièces neuves ou pour la réparation, ces opérations
étant placées sous la responsabilité d'un fournisseur ou d'un réparateur agréé. La responsabilité finale
incombe à l’autorité de conception.

Aeronavtika - Varjeni in trdo spajkani sestavi za konstrukcije v aeronavtiki - Spoji kovinskih materialov pri varjenju z elektronskim snopom - 001. del: Kakovost varjenih sestavov

Ta evropski standard določa pravila, ki jih je treba izpolniti za zagotovitev kakovosti spojev kovinskih materialov pri varjenju z elektronskim snopom (referenčna številka 51 v skladu s standardom EN ISO 4063). Brez zadržkov se uporablja za izdelavo novih delov ali popravila, pri čemer je za te dejavnosti odgovoren odobreni proizvajalec ali dobavitelj. Končno odgovornost ima organ, pristojen za zasnovo.

General Information

Status
Published
Publication Date
12-Jun-2012
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
06-Jun-2012
Due Date
11-Aug-2012
Completion Date
13-Jun-2012

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2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Aeronavtika - Varjeni in trdo spajkani sestavi za konstrukcije v aeronavtiki - Spoji kovinskih materialov pri varjenju z elektronskim snopom - 001. del: Kakovost varjenih sestavovLuft- und Raumfahrt - Schweiß- und Lötverbindungen für die Luft- und Raumfahrt - Verbindungen metallischer Werkstoffe mittels Elektronenstrahlschweißen - Teil 001: Qualität der SchweißverbindungenSérie aérospatiale - Assemblages soudés et brasés pour constructions aérospatiales - Assemblages de matériaux métalliques soudés par faisceau d'électrons - Partie 001: Qualité des assemblages soudésAerospace series - Welded and brazed assemblies for aerospace construction - Joints of metallic materials by electron beam welding - Part 001: Quality of welded assemblies49.035Sestavni deli za letalsko in vesoljsko gradnjoComponents for aerospace construction25.160.40Varjeni spoji in variWelded jointsICS:Ta slovenski standard je istoveten z:EN 4677-001:2012SIST EN 4677-001:2012en01-september-2012SIST EN 4677-001:2012SLOVENSKI
STANDARD



SIST EN 4677-001:2012



EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 4677-001
May 2012 ICS 25.160.40; 49.035 English Version
Aerospace series - Welded and brazed assemblies for aerospace construction - Joints of metallic materials by electron beam welding - Part 001: Quality of welded assemblies
Série aérospatiale - Assemblages soudés et brasés pour constructions aérospatiales - Assemblages de matériaux métalliques soudés par faisceau d'électrons - Partie 001: Qualité des assemblages soudés
Luft- und Raumfahrt - Schweiß- und Lötverbindungen für die Luft- und Raumfahrt - Verbindungen metallischer Werkstoffe mittels Elektronenstrahlschweißen - Teil 001: Qualität der Schweißverbindungen This European Standard was approved by CEN on 16 January 2010.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre:
Avenue Marnix 17,
B-1000 Brussels © 2012 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 4677-001:2012: ESIST EN 4677-001:2012



EN 4677-001:2012 (E) 2 Contents Page Foreword . 31 Scope . 42 Normative references . 43 Terms and definitions . 53.1 General . 53.1.1 Electron beam welding . 53.2 Technical terms . 53.2.1 Welding parameters . 53.2.2 Other technical terms . 73.3 General terms . 94 Weldability . 114.1 Notion of weldability . 114.2 Degrees of weldability . 115 Symbols and acronyms . 116 General requirements . 126.1 Weld classification . 126.1.1 Manufacturing new parts . 126.1.2 Repair . 126.2 Welding machines . 126.3 Operators and setters . 126.3.1 Training . 126.3.2 Qualification . 136.4 Responsibility . 157 Technical requirements for manufacturing new parts . 157.1 Materials . 157.2 Preparation of welding procedure specification . 157.2.1 Generality of procedure . 157.2.2 Welding procedure specification . 167.2.3 Qualification tests . 177.3 Process monitoring and inspection in manufacture . 257.3.1 General . 257.3.2 Manufacturing data sheet . 257.3.3 Follow up and inspection of manufacturing conditions . 257.3.4 Testing and inspection during manufacturing . 267.3.5 Sentencing of test specimens . 277.4 Acceptance of welded assemblies . 287.4.1 Requirements . 287.4.2 Acceptance criteria . 297.4.3 Sentencing of assemblies . 297.4.4 Repair of non-conforming welded joints . 298 Technical repair requirements . 299 Special case . 30
SIST EN 4677-001:2012



EN 4677-001:2012 (E) 3 Foreword This document (EN 4677-001:2012) has been prepared by the Aerospace and Defence Industries Association of Europe - Standardization (ASD-STAN). After enquiries and votes carried out in accordance with the rules of this Association, this Standard has received the approval of the National Associations and the Official Services of the member countries of ASD, prior to its presentation to CEN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by November 2012, and conflicting national standards shall be withdrawn at the latest by November 2012. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. SIST EN 4677-001:2012



EN 4677-001:2012 (E) 4 1 Scope This European Standard defines the rules to be satisfied to ensure the quality of joints of metallic materials by electron beam welding (reference number 51 according to EN ISO 4063). It applies unreservedly to the manufacturing of new parts or for repair, these operations being under the responsibility of an approved manufacturer or supplier. The final responsibility is with the design authority 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. EN 875, Destructive tests on welds in metallic materials — Impact tests — Test specimen location, notch orientation and examination EN 895, Destructive tests on welds in metallic materials — Transverse tensile test EN 910, Destructive tests on welds in metallic materials — Bend tests EN 4632-001, Aerospace series — Welded and brazed assemblies for aerospace constructions — Weldability and brazeability of materials — Part 001: General requirements EN 4632-002, Aerospace series — Welded and brazed assemblies for aerospace constructions — Weldability and brazeability of materials — Part 002: Homogeneous assemblies aluminium and aluminium alloys EN 4632-003, Aerospace series — Weldability and brazeability of materials in aerospace constructions — Part 003: Welding and brazing of homogeneous assemblies of unalloyed and low alloy steels EN 4632-004, Aerospace series — Welded and brazed assemblies for aerospace constructions — Weldability and brazeability of materials — Part 004: Homogeneous assemblies highly alloyed steels EN 4632-005, Aerospace series, Weldability and brazeability of materials in aerospace constructions — Homogeneous assemblies of heat resisting Ni or Co base alloys EN 4632-006, Welded and brazed assemblies for aerospace constructions — Weldability and brazeability of materials — Part 006: Homogeneous assemblies titanium alloys EN ISO 4063, Welding and allied processes — Nomenclature of processes and reference numbers
(ISO 4063) EN ISO 5817, Welding — Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding excluded) — Quality levels for imperfections (ISO 5817) EN ISO 6507-1, Metallic materials — Vickers hardness test — Part 1: Test method (ISO 6507-1) EN ISO 6947, Welding and allied processes — Welding positions (ISO 6947) EN ISO 10042, Welding — Arc-welded joints in aluminium and its alloys — Quality levels for imperfections (ISO 10042) EN ISO 14731, Welding coordination — Tasks and responsibilities (ISO 14731) EN ISO 14744-1, Welding — Acceptance inspection of electron beam welding machines — Part 1: Principles and acceptance conditions (ISO 14744-1) SIST EN 4677-001:2012



EN 4677-001:2012 (E) 5 EN ISO 14744-2, Welding — Acceptance inspection of electron beam welding machines — Part 2: Measurement of accelerating voltage characteristics (ISO 14744-2) EN ISO 14744-3, Welding — Acceptance inspection of electron beam welding machines — Part 3: Measurement of beam current characteristics (ISO 14744-3) EN ISO 14744-6, Welding — Acceptance inspection of electron beam welding machines — Part 6: Measurement of stability of spot position (ISO 14744-6) EN ISO 15609-3, Specification and qualification of welding procedures for metallic materials — Welding procedure specification — Part 3: Electron beam welding EN ISO 17659:2004, Welding — Multilingual terms for welded joints with illustrations (ISO 17659:2002) ISO 857-1:1998, Welding and allied processes — Vocabulary — Part 1: Metal welding processes ISO 4969, Steel — Macroscopic examination by etching with strong mineral acids ISO 22826, Destructive tests on welds in metallic materials — Hardness testing of narrow joints welded by laser and electron beam (Vickers and Knoop hardness tests) ISO 24394, Welding for aerospace applications — Qualification test for welders and welding operators — Fusion welding of metallic components ISO/TR 25901, Welding and related processes — Vocabulary 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 857-1:1998 and EN ISO 17659:2004 and the following apply. 3.1 General 3.1.1 Electron beam welding fusion welding process using the transformation of the kinetic energy of beam electrons into thermal energy when they strike the material Note 1 to entry: The electrons are obtained from a cathode heated under a secondary vacuum (1 Pa to 10-4 Pa). Note 2 to entry: The welding operation may be performed under a controlled atmosphere, generally under a primary vacuum (100 Pa to 1 Pa) or secondary vacuum. 3.2 Technical terms 3.2.1 Welding parameters 3.2.1.1 run-out interval encompassing all geometrical irregularities of the joint plane Note 1 to entry: This interval is measured on the detail parts, positioned in their welding setup, and is used as a reference to determine the minimum width of the weld zone. 3.2.1.2 beam centering alignment of the beam axis on the joint plane SIST EN 4677-001:2012



EN 4677-001:2012 (E) 6 3.2.1.3 beam deflection controlled movement of the beam in relation to the physical axis of the gun 3.2.1.4 level distance difference in level (height) between two detail parts at the joint plane 3.2.1.5 firing (working) distance distance between the impact point of the beam on detail parts and a reference surface linked to the gun or the machine (example: middle of the closest focusing coil of the detail part, electron gun base) 3.2.1.6 specific welding energy defined by ratio between the beam power over the welding speed, multiplied by 60 0001(cm/min)60(Ampere)(Volt)×××VIU (in kJ/cm) 3.2.1.7 focusing current intensity intensity of the current crossing the focusing coil enabling electron beam concentration on a point called the focusing point Note 1 to entry: The intensity may be constant or modulated. 3.2.1.8 beam current electron flow emitted by the cathode Note 1 to entry: This current may be constant or modulated. 3.2.1.9 clearance before welding (Fit up) distance measured on a straight section of the joint between the surfaces to be welded 3.2.1.10 slope (or ramp) up operating conditions for which the penetration depth varies incrementally 3.2.1.11 focusing level distance between the beam impact point on the detail parts and the focusing point Note 1 to entry: Conventionally, this distance is negative when the focusing point is within the detail parts. 3.2.1.12 perveance ratio of the beam current over the acceleration voltage at power 3/2 tecUI=23 3.2.1.13 beam power product of the acceleration voltage and the beam current SIST EN 4677-001:2012



EN 4677-001:2012 (E) 7 3.2.1.14 acceleration voltage difference in potential between the cathode and the anode, used to create the electric field intended to accelerate the electrons 3.2.1.15 beam oscillation periodic movement of the beam axis in relation to the weld pool Note 1 to entry: This oscillation is defined by the signal shape, its amplitude, frequency and direction in relation to that of welding. 3.2.1.16 welding speed length of the weld on beam impact side produced per time unit 3.2.2 Other technical terms 3.2.2.1 welding campaign series of welding operations on identical parts, executed on the same machine, without any changes of welding parameters, without performing other welds on the machine, without interrupting manufacturing for more than a week 3.2.2.2 welding cycle succession of different welding phases performed by the welding machine to make a weld 3.2.2.3 tacking pass pre-assembling of elementary detail parts using the same process as the one used for welding, consisting of making a slightly penetrating, narrow weld, continuous or discontinuous along the joint plane, with the purpose of maintaining the detail parts in position 3.2.2.4 adjustment verification specimen a flat test specimen of the same material, subjected to the same heat treatments as the detail parts, on which a melt run will be made in the middle using the parameters identical to those used for parts, and for which the relationship between the micrographic shape of the cross section cut of the bead and that obtained on test specimens or real parts has been previously defined 3.2.2.5 structural state metal crystalline structural state 3.2.2.6 manufacturing performance of welding operations on new parts or repairs to existing assemblies (or products) 3.2.2.7 stabilized manufacturing manufacturing for which the reliability can be established without quality issue over several welding campaigns, of which the number is previously defined by the appropriate department of the design authority 3.2.2.8 smoothing pass or cosmetic pass remelted surface of the welded zone SIST EN 4677-001:2012



EN 4677-001:2012 (E) 8 3.2.2.9 batch of parts set of parts with the same reference from:  the same welding campaign;  the same heat treatment batch;  traced material (processing, chemical analysis, …). 3.2.2.10 material/Parent material material or metal used to make the detail parts 3.2.2.11 filler material additional alloy or metal used to make the weld of an assembly or a deposit 3.2.2.12 tooling equipment required to hold and position parts before and during welding 3.2.2.13 beam stopper (catcher) part intended to intercept the residual energy crossing the beam in the case of a through weld Note 1 to entry: The material making up the beam catcher should be of a same grade or a grade compatible with the required quality of the assembly. 3.2.2.14 detail part individual element to be assembled with other elements to make up a complete part 3.2.2.15 part - product assembly comprising several assembled detail parts 3.2.2.16 tack welding pre-assembly of detail parts by welding consisting of a set of tacks along the joint plane, intended to hold the detail parts in position 3.2.2.17 pre-heating heating of detail parts before welding without fusion Note 1 to entry: This operation will be carried out with an unfocused beam or any other process not involving magnetism. 3.2.2.18 through weld case where the beam crosses all the thickness of parts to weld and case where the beam propagates through all the parts to be welded 3.2.2.19 blind weld case where the beam only crosses part of the thickness of the parts to weld and case where the beam only partially propagates through the thickness of the parts to be welded 3.2.2.20 qualification test specimen welded assembly to be used for inspection purposes SIST EN 4677-001:2012



EN 4677-001:2012 (E) 9 3.2.2.21 manufacturing test specimen – test specimen representing manufactured parts to be welded under the same conditions as those parts; – test specimen made from the same material grade, in the same condition, with the same dimensions as the manufactured part. Note 1 to entry: Manufacturing test specimens may be actual parts. 3.2.2.22 pool support element positioned on detail parts to prevent the fused metal from overflowing Note 1 to entry: The material making up the pool support shall be of the same base alloy as the detail parts, to prevent any weld contamination. Note 2 to entry: The pool support may be positioned as illustrated in Figures 1 to 3:
Keys 1 E.B. Keys 1 E.B. Keys 1 E.B. Figure 1 — Back support Figure 2 — Back-side support Figure 3 — Front-side support 3.2.2.23 witness lines alignment lines on both sides (upper and root) of the detail parts to ensure good location and the avoidance of lack of fusion 3.2.2.24 post-weld heat-treatment treatment intended to provide the parent material and the weld zone with the requisite conditions and properties 3.3 General terms 3.3.1 manufacturer or subcontractor organisation who assembles, or manufactures and assembles the elements or subassemblies into assemblies 3.3.2 supplier individual or company holding a contract or order that it has accepted, binding it to the customer to perform the services defined therein 3.3.3 customer individual or company placing a contract or order and who may or may not be the design authority 3.3.4 operator person who performs the welding operations using a mechanised or automated process SIST EN 4677-001:2012



EN 4677-001:2012 (E) 10 3.3.5 qualification action recognizing that a welder, product, etc. is capable of fulfilling the role for which he/it is intended 3.3.6 repair act consisting in making acceptable a part that was felt to be beyond the acceptance criteria after its normal manufacturing and inspection cycle Note 1 to entry: Bringing into conformity of a part which had been damaged during operation 3.3.7 setter person responsible for fully programming the machine, the beam analysis and finalization of welding procedure specification parameters and, if necessary, performing welding operations by a mechanized or automated process 3.3.8 repairer supplier in the specific field of repairs 3.3.9 competent department specialist department with specific duties within a company, such as:  design office,  quality department,  laboratory,  methods office 3.3.10 official supervisory body governmental authorities or approved organisations responsible for ensuring equipment conformity with the definition file 3.3.11 design authority the organisation responsible for the design of the welded assembly and for defining the performance and inspection requirements 3.3.12 welding coordinator See EN ISO 14731:2006 3.4.1 Flat position PA horizontal welding, with beam axis vertical 3.4.1.1 Horizontal-vertical position PB horizontal welding 3.4.1.2 Horizontal position PC horizontal welding, welding axis horizontal 3.4.1.3 Horizontal overhead position PD horizontal welding, overhead SIST EN 4677-001:2012



EN 4677-001:2012 (E) 11 3.4.1.4 Overhead position PE horizontal welding, overhead, welding axis vertical 3.4.1.5 Vertical up position PF welding up 3.4.1.6 Vertical down position PG welding down 4 Weldability 4.1 Notion of weldability a metallic material is considered to be weldable to a given degree, by a given process or for a given type of application when, provided that the corresponding precautions are taken, it lends itself to the production of a weld which, through its characteristics and the consequences of its presence, meets the required properties chosen as the basis for the judgement 4.2 Degrees of weldability the weldability of materials is assessed according to the following four degrees:  degree 1: material with very good weldability, requiring no particular precautions. Preferred.  degree 2: material with good weldability but likely to require special welding precautions (for example, preheating, low feedrate).  degree 3: material with poor weldability, requiring specific development for each type of part and likely to lead to manufacturing problems. Inadvisable.  degree 4: material with very poor weldability. To be avoided. 5 Symbols and acronyms e Thickness of the thinnest part of the assembly E Total thickness of 2 sheets I Beam current T Tempering, structural hardening, ageing U Acceleration voltage V Welding speed E.B. Electron beam TIG Tungsten inert gas SIST EN 4677-001:2012



EN 4677-001:2012 (E) 12 6 General requirements 6.1 Weld classification 6.1.1 Manufacturing new parts The design authority, at the time of part design, shall allocate a weld class to each assembly: 1, 2 or 3 according to a decremental functional severity order. The requirements are listed in Table 1. A higher severity weld class may be allocated to meet specific problems such as manufacturing complexity or interpretation of inspection operations, etc. Table 1 — Weld class allocation requirements Part with function Assembly weld rupture can affect normal operation of the part without significant consequences Vital 1 2 Other 2 3
A given part may have several different weld classes. Each weld class is associated with all of the following conditions:  implementation before manufacturing;  follow up during manufacturing;  inspection on welded assembly;  acceptance criteria. The design authority shall insure that inspection requirements are adequate to demonstrate compliance with the design requirements. 6.1.2 Repair The repairer shall comply with the requirements of the design authority. 6.2 Welding machines The machines used for welding shall comply with EN ISO 14744-1. In particular, machines shall have undergone specific qualification tests for use in the aerospace industry when they were acquired or renovated. NOTE Standard in preparation on electron beam welding machine – qualification specifications. 6.3 Operators and setters 6.3.1 Training 6.3.1.1 Operator training For any manufacturing or repair operation, the electron beam-welding operator shall have followed a training course given by the competent department of the manufacturer (part manufacturer), or an external training organization, with regard to:  technical training on the process; SIST EN 4677-001:2012



EN 4677-001:2012 (E) 13  operation of the machine used (electrical power supply, replacement of the machine electron emitter system, etc.);  safety related to this machine and the welding operation;  equipment, instruments and tooling required for correct operation of the machine, and performance of the welding operation;  display and verification of welding procedures;  positioning of the focal point in relation to the part surface;  alignment check of the beam in relation to the joint plane;  appearance and geometrical check of welded assemblies. The operator shall weld beads and/or melt runs on standard parts and/or test specimens and/or manufacturing test specimens according to the validated welding procedure specification corresponding to his training. 6.3.1.2 Setter training For any manufacturing or repair operation, the electron beam welding setter shall have followed the operator training course, as well as a theoretical and technical training course given by the competent department of the manufacturer (part manufacturer), and/or an external training organization. The training concerns:  complete programming of the machine;  analysis of beam quality (EN ISO 14744-2, EN ISO 14744-3 and EN ISO 14744-6);  optimisation of welding parameters and preparation of welding procedure specification etc. The setter shall prepare a welding procedure specification in order to validate his training. 6.3.2 Qualification 6.3.2.1 Operator qualification See Table 2. Table 2 — Operator qualification requirements Test Requirement Near vision Visual acuity (eyesight) shall be examined for near vision. Welder and Welding operators shall have vision acuity of 20/30 or better in each eye, and shall be able to read the Jaeger No. 2 eye chart at 400 mm or to pass an equivalent test as specified by an optometrist. Corrective vision may be used to fulfil eye test requirements. Colour perception Be capable of distinguishing and differentiating colo
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