Electron Beam
welding process
The principle of electron beam welding is relatively simple:
electrons are accelerated by a high difference electrical
potential and concentrated on a target. The electron’s kinetic
energy is then transformed, for the most part, into thermal
energy melting the metal and producing welds.
Electron beam welding general presentation
The electron emission
Some materials such, tantalium or hexaboride
of lanthanum allow to get an appropriate quantity of free electrons when they are,heated up to a high
temperature, and are used for emissive gun elements manufacturing.
Inside electron guns these emissive elements can be heated up by two different modes:
• direct heating by joule effect,
• indirect heating by use of an electron bombardment from a filament.
The electron acceleration
In order to be extracted from the surface of the emissive element, the free electrons need to be submitted to a strenuous electrostatic field. The potential difference between the emissive element (cathode) and the opposite electrode (anode) allows to create this field, which accelerates the electrons by giving them a kinetic energy.
Electron Beam creation
In the inter-electrode space, the electrodes geometry defines the electron trajectories. First, the electron beam converges in the anode drilled in its center.
Then, the beam continues by inertia and diverges. In order to be used for welding, the beam is focused by an exciting coil placed in the gun. The focus length is set up by current adjustment inside the focusing coil.
Vacuum environment necessity
The emissive element and the electrodes are placed in the gun. The piece to be welded is located in the welding chamber.
Since the collision of free electrons and gas molecule which would induce beam dispersion and a decrease in the carried power density, the gun and the piece to be welded are vacuum pumped.
The dimension of the welding chamber depends on the dimension of the parts to be welded with its positioning equipment and can vary from few litres up to few ten m3.
Air Liquide Welding indirect heating gun
Filament heating voltage
+ Reference potential Bias Voltage Cathode Filament Accelerating voltage Wehnelt Anode Focusing coil Target: parts to be welded +
-Since the beginning of the Electron Beam Welding process 40 years ago and its first
dedicated application; the welding of tubular fuel elements of nuclear cells; Electron beam
welding has since being used world-wide and its range of applications extends from
welding thin foil to workpieces with walls over 100 mm thick.
Electron Beam process
The electrons are small particles of matter with small mass. When they are accelerated they hit the piece transferring their kinetic energy into thermal energy ensuring metal melting creating plasma of metallic vapours.
The E.B. welding process is a high energetic process allowing to use very high power up to ten's of kW on small surfaces of 5/10 of mm diameter.
However, the total heat input is actually much lower than that of any arc welding process.
Principals advantages of the electron beam
welding process:
• very small deformationsafter welding,
• very thick materials(exceeding 60 mm with steel) in one pass, • possibility to weld all the steel, copper, nickelmaterials, aluminium,
metals sensitive to oxygen and other gases as zirconium, titanium… • no filler metaland no gas,
• high welding quality. The welds obtained are exceptionally pure, • high reliability, • high reproducibility, • high productivity. U13% chrome steel U20 mm thickness UOne pass penetration butt welding UWelding speed 1 m/min UPower 10.3 kW
U2 strips stainless steel of 0.1 mm thickness
UOverlapping welds
UZirconium Zr2 of 10 mm thickness
UFillet weld
UTotal penetration 14.2 mm
UWelding speed 1 m/min
Air Liquide Welding answer:
Electron Beam welding equipment
A large range of solutions
The specific chamber, tools and vacuum system have to be defined according to the piece characteristics and the needs in term of quality and quantity.
For that, we will define jointly your specific requirement in term of:
• piece characteristics with drawing and especially joint definition,
• grade steel (chemical composition), • the required quantity (pieces/hour), • criteria of acceptability,
Air Liquide Weldingoffers:
• In term of production rate some Turn tables to load in masked time, robot for handling...
• In term of process quality, Recorder, Video control (process), Beam deflection.
Thanks to our experienced teams, we can respond
to yours specifics need.
Central system control by CNC
Based on its long experience, Air Liquide Welding developed a specific software dedicated to the E.B.W process which controls the overall machine operation. Through a C.N.C, it manages:
• The operation cycle, • The vacuum system, • The numerised axis,
• The main parameters through the E.B.Generator. A control panel will receive the general controls of the machine (Automatic cycle start/stop, welding chamber venting…) and can on demand be modified to accept the specific control required by the customer.
A very useful remote control box permits to modify the current of the focalisation and the current beam closed to the welding chamber. Thus, through the viewing
Remote control box
Start gun shot Axis displacement choice Focalisation current set Axis displacement hand crank
Emergency Stop
End gun shot
Beam current set
ST Standard gun based on a motorized displacement carriage. One manual closing door equipped with 2 viewing windows. Two Headstocks.
Examples of a universal welding chamber for automotive application (gear-wheels...)
Intensive working for over 35 years
in industries
All our E.B generators are low voltage triode gun. It gives many advantages as:
• A beam a little bit thicker and consequently a much larger tolerance in the preparation of the edge to be welded.
• Low emission of X rays parasite.
Moreover, our solid cathodes are heated indirectly and are made from W in some case (Zirconium welding) and more generally in LaB6 material. These last materials present the characteristic to work at low temperature compared to other materials such as W or Ta. It offers a very long life from 1000 hours up to 2000 hours in comparison with the common consumable parts of industrial electron beam generator. Moreover, the electrodes have a short coupling. It confers to the gun a very good stability of electronic trajectories and a good repeatability of the impact position.
ST Standards series:
autonomous E.B generator
Air Liquide Weldingproposes a large range of autonomous electron beam welding generator from 6 kW - 45 kV to 100 kW - 100 kV made up of:
• Our triode gun with indirect cathode heating, • Our high voltage resonance power supply
assembly with oil free and auxiliary tank, • A high voltage cable with low capacitance. An electrical cabinet with all the control loop of the process, a P.L.C, and a control box to set all the fundamentals E.B.W parameters.
Thus, our E.B.Generator can work alone or under control of our C.N.C. In this way, the maintenance is made easier and on the other hand, we can on demand realize refurbishment on existent machine.
Our ST Standard gun
Think different: Think Electron Beam welding
The wide range of energy density of the electron beam allows to readily obtain sound welds, presenting satisfactory mechanical characteristics and almost without any deformation, on materials for which a conventional welding process would be extremely complex, or even impossible, to perform:
A new fashion to design your pieces
100 mm thickness titanium butt weld
Fillet welds of stainless steel
Cost Reduction
The same piece welded by E.B.W Integral machined piece
Up to 2 pieces welded by minute
possible on this kind of application.
Electron Beam welding activity
Electron Beam welding workshop
Air Liquide Welding is part of the Air Liquide group the world
leader in industrial and medical gases and related services.
The group offers innovative solutions based on constantly
enhanced technologies to help manufacture many indispensable
products and preserve life.
Air Liquide Welding experience
The electron beam welding installations offered by Air Liquide Weldingis the result of the integration of the technologies developed and the experience gained from our industrial achievements over the last thirty five years in electron beam technology.
Air Liquide Weldinghas many more references in electron beam welding in technological environment known through the trademark SAFMATIC as varied as:
• aeronautics,
•mechanic, hydraulic, pneumatic components, • motorcar automobile,
• nuclear,
• boiler construction.
Consequently the elements of our installation have already met the many functioning criteria required in those demanding industrial contexts. The optimization of technical characteristics due to those different applications has lead to a high level of stability and reliability which is well appreciated by our Customer.
Project feasibility
and small size production
Our means of production and our means of control are at your service for prototypes and small quantities production. Machine Characteristic 12 kW maxi. Controlled by micro-computer Enclosure: 24 dm3
Controlled axis for radial welding
10 kW maxi. Controlled by micro-computer
Enclosure: 900 x 400 x 400
Controlled axis for axial and radial welding
6 kW maxi. Controlled by micro-computer
Enclosure: 520 x 410 x 460
Controlled axis for axial and radial welding
Benefit from the research
department of Air Liquide Welding
Our research and development team is composed of more than 140 persons working to develop innovative solutions in:
• metallurgy, • health and safety, • productivity, • gas, equipment, • consumables and
tool combinations.
Innovation is a state of mind for the group employees. This is clearly illustrated through the many patented inventions developed by our researchers in the CTAS (Technical Centre for Welding Applications) the largest
W 000 274 587 - © Air Liquide W
elding - 03/2009 - Ed.1 - PLBD 5584
Contacts
BELGIUM
AIR LIQUIDE WELDING BELGIUM SA Z.I. West Grijpen - Grijpenlaan 5 - 3300 TIENEN Tel.: +32 16 80 48 20 - Fax: +32 16 78 29 22
CHINA
SAF SHANGHAI REP.OFF. Rm 722 Pine City Hotel
777 Zhao Jia Bang Lu - SHANGHAI 200032 Tel.: +86 21 64 43 89 69 - Fax: +86 21 64 43 58 97
CZECH REPUBLIC
AIR LIQUIDE CZ S.R.O. - Welding and Cutting
Podnikatelská 565 - Areál SVUM - 190 11 PRAHA 9 - Búchovice Tel.: +420 274 023 163 - Fax: +420 274 023 233
FRANCE
AIR LIQUIDE WELDING FRANCE
13, rue d’Épluches - BP 70024 Saint-Ouen l'Aumône 95315 CERGY PONTOISE Cedex
Tel.: +33 1 34 21 33 33 - Fax: +33 1 34 21 31 30 GERMANY OERLIKON SCHWEISSTECHNIK GmbH Industriestrasse 12 - D-67304 EISENBERG/PFALZ Tel.: +49 6351 4760 - Fax: +49 6351 476 335 HUNGARY
AIR LIQUIDE HUNGARY - Welding & Cutting Krisztina krt. 39/b - H-1013 BUDAPEST Tel.: +36 1 339 8650 - Fax: +36 1 339 8649
ITALY
AIR LIQUIDE WELDING ITALY Via Torricelli 15/A - 37135 VERONA
Tel.: +39 045 82 91 511 - Fax: +39 045 82 91 536
LUXEMBOURG
AIR LIQUIDE WELDING LUXEMBOURG S.A.
5 rue de la Déportation - BP 1385 - L-1415 LUXEMBOURG Tel.: +352 48 54 56 - Fax: +352 48 54 57
MALAYSIA
SAF-OERLIKON MALAYSIA SDN BHD No 10, Jalan TPP 5/1
Taman Perindustrian Puchong - 47100 PUCHONG, SELANGOR Tel.: +603 8060 8638 - Fax: +603 8061 620
NETHERLANDS
AIR LIQUIDE WELDING NETHERLANDS Rudonk 6 B - NL 4824 AJ BREDA
Tel.: +31 76 541 00 80 - Fax: +31 76 541 58 96
POLAND
AIR LIQUIDE WELDING POLSKA - SP. Z.o.o UL. Porcelanowa 10 - 40-246 KATOWICE Tel.: +48 32 609 04 50 - Fax: +48 32 609 04 60
PORTUGAL
AIR LIQUIDE SOLDADURA LDA
Rua Dr. António Loureiro Borges, 4-2° Arquiparque Miraflores - 1495-131 ALGÉS
Tel: +351 21 41 64 900 - Fax: +351 21 41 69 40
ROMANIA
DUCTIL
Aleea Industriilor Nr 1 - 120224 BUZAU Tel.: +40 238 722 058 - Fax: +40 238 716 861
RUSSIA
AIR LIQUIDE WELDING
17 Vorontsovskaya Str. - 109147 MOSCOW Tel.: +7 495 641 28 98 - Fax: +7 495 641 28 91 SCANDINAVIA OERLIKON SKANDINAVIEN AB Krossverksgatan 7 - 216 16 LIMHAMN Tel.: +46 (0)40 670 15 00 - Fax: +46 (0)40 670 15 01 SLOVAKIA
AIR LIQUIDE WELDING CENTRAL EUROPE S.R.O. Hlohovecká 6 - 951 41 NITRA - LUŽIANKY Tel.: +421 37 692 4610 - Fax : + 421 37 651 28 04
SPAIN
OERLIKON SOLDADURA SA
Poligono Industrial la Noria Carretera de Castellon Km-15,500 - 50730 El Burgo de Ebro - ZARAGOZA Tel.: +34 976 10 47 00 - Fax: +34 976 10 42 67 SWITZERLAND OERLIKON SCHWEISSTECHNIK AG Mandachstrasse 54 - CH 8155 NIEDERHASLI Tel.:+41 44 3076 111 - Fax: +41 44 3076 112 THAILANDE
AIR LIQUIDE WELDING THAILAND Co. Ltd.
40 Moo 6 - Ramindra Road Km 9.5 - KHANNAYAO, BANGKOK 10230 Tel.: +66 29 43 2250 - Fax: +66 29 43 2256
UAE
AIR LIQUIDE WELDING MIDDLE EAST FZE Jebel Ali free zone warehouse No. FZS1AH05 P.O. BOX 18734 - Jebel Ali - DUBAI
Tel.: +971(0)48861606 - Fax: +971(0)48861608
U. K.
AIR LIQUIDE WELDING Ltd
Low March / London Road - DAVENTRY - Northants NN11 4SD Tel.: +44 1 327 70 55 11 - Fax: +44 1 327 70 13 10
UKRAINE
AIR LIQUIDE WELDING UKRAINE, Llc.
1 rue Proskura - bureau 106A - 61070 KHARKOV Tel.: +380 577 546 867 - Fax: +380 577 546 867
www.airliquide.com
Contacts for other countries
ALW Export Department Italy
Via Torricelli15/A 37135 VERONA
Tel.: +39 045 82 91 511- Fax: +39 045 82 91 536 E-mail: [email protected]
ALW Export Department France
13, rue d'Epluches
BP 70024 Saint Ouen l'Aumône 95315 CERGY-PONTOISE Cedex
Tel.: +33 1 34 21 33 33 - Fax: +33 1 30 37 19 73 E-mail: [email protected]
ALW Export Department Switzerland
OERLIKON WELDING LTD Mandachstrasse 54 CH - 8155 Niederhasli
Tel.: +41 44 3076 111 - Fax: +41 44 3076 212 E-mail: [email protected]
