Author: Maria Francheteau
Master Classes at EDF
Assurance of quality welds for manufacturer and customer
In its manufacturing of components for high grade stainless steel tube systems in the field of hygienic applications, Dockweiler, worldwide leader in the manufacture of components for high quality stainless steel tube systems for semiconductor, pharmaceutical, biotechnological, and photovoltaic applications, has a system of efficient quality assurance procedures, including a rigorous inspection of all incoming semi-finished products and a distinctive classification concerning the weldability of materials.
New supports for orbital welding heads
Tired of untidy workbenches? Or looking for user-friendly supports to hold your favourite welding heads?
Polysoude presents its brand new range of professional accessories: Orbital welding head supports and holders.
To assure secure fixation and prevent damages on your welding heads, we are pleased to offer now our new supports, which can also be part of a complete professional solution. These packages can include the welding head, the TCIs and the support for workbench or welding table.
In order to adapt to any application for MW and UHP 250 and 500 welding heads, these supports are available with quick-release clamp or bracket for bench vice. Made from a qualitative aluminum frame, supports include rubber shims compatible for both UHP and MW welding heads.
For the UHP 625 welding head, a dedicated holder for workbench or welding table is now available, too.
Ready to find out more about our new welding head supports? Just click on the link below.
Looking forward to bringing professionalism always further in your workshop.
New roadmap towards enhanced relationship with Russian State Research Center
Recently, a delegation composed by members of Polysoude France and Russia had the opportunity to visit the Cniitmash state research center and meet with institute’s General Director Mr Orlov and the Director of the Welding Institute, Mr Volobuyev.
This visit came as a proof of the trustful relationship between both partners. In fact, the research institute houses Polysoude’s Technology Center in Moscow with some samples, torch manipulators such as a column & boom, spare parts and other displays.
The research center is a very strategic partner for the CIS market. In fact it is part of Atomenergomash, a mechanical engineering division of ROSATOM one of the leaders in the world's Nuclear energy industry (300.000 employees, representing 1/3 world market share, leader in global uranium enrichment services, covering 17.7% of the global nuclear fuel market).
The parties agreed to enhance their cooperation on a regular basis in the years to come. For example, the talks covered issues relating to the implementation of modern welding and surfacing technologies at the division’s mechanical engineering facilities.
Polysoude’s team is looking forward to further advise researchers of the institute on coming 28th May at the open day organised at Cniitmash.
Representing Cniitmash, General Director Mr V. V. ORLOV and the Director of the Welding Institute, Mr Yu. S. VOLOBUYEV
Polysoude’s team composed by Hans-Peter MARINER, CEO, Pascal WEBER, Sales Director, D. A. GUTOROV, Head of Polysoude Russia and D. V. KRYUKOV, Head of Sales of Representation office based in Moscow.
Orbital TIG welding technique ensures quality and productivity
Polysoude’s Orbital TIG welding is renowned for outstanding quality and reliability, especially under harsh environmental conditions and severe time restraints. This was shown by the Ruhlermoor project, completed in Northern Germany in 2017. The project involved laying 10.7k of duplex steel pipeline and connecting two pump stations.
Use of the TIG process in the industry
Industries which apply the TIG welding process:
Aircraft industry
The aircraft industry was the first to recognise the importance of orbital welding for its purposes. More than 1,500 welds are necessary to complete the high pressure system of one single plane. Manual welding of the small, thin-walled tubes is extremely difficult and the required consistent joint quality cannot be guaranteed. However, welding procedures using orbital welding have provided a solution, in which the parameter values are reliably controlled by the equipment and the final welds meet the same quality level as the qualified test welds.
Food, diary and beverage industries
The food, diary and beverage industries need tube and pipe systems meeting delicate hygienic requirements. Full penetration of the welded joints is necessary; any pit, pore, crevice, crack or undercut can become a dead spot, where the medium is trapped and pathogenic bacteria growth (Listeria etc.), could occur. Smooth surfaces everywhere inside the tubes enable successful cleaning and complete sterilisation of the system. The requisite surface quality can only be ensured if orbital TIG equipment is used to weld these critical joints. Therefore, most current standards and specifications require manufacturers of hygienic installations to apply this process.
Pharmaceutical and biotechnology industries
Plants in pharmaceutical industries must be equipped with pipe systems for the transport and treatment of products and for the safe supply of clean steam and injection water. For injection water and its derivatives, which are intended for injection into the human body, the purity requirements are particularly high. Any trace of corrosion cannot be tolerated, therefore welds must be corrosion resistant, especially to incidents such as the partial overheating of base material. Joints made by orbital welding meet the high standards for extended corrosion resistance. Additionally, to avoid any subsequent oxidation or corrosion, their smooth surface can be passivated.
Fabrication of semi-conductor devices
For the fabrication of semi-conductor devices, electro-polished stainless steel tubes are installed as process gas lines, mostly with an OD of 6.3 mm and a wall thickness of 0.9 mm. The ultra-pure process gas must pass through the tubes without picking up moisture, oxygen, particles or any other contaminants. The acceptance criteria for these installations are extremely stringent. Uniform welds with small weld beads are required, in order to minimise the weld surface in the tubes, allow for full penetration on the ID and ensure the absence of discoloration, etc. Only the reliability and consistency of orbital welding equipment, used by experienced operators, often even under adverse conditions on site, can enable such tasks to be successfully carried out.
Chemical industries
A considerable proportion of plant equipment for chemical industries is manufactured and installed by means of orbital welding. Chemical apparatus comprise of tubes, heat exchangers and converters, which are made of corrosion-resistant or refractory metals, or alloys of titanium, zirconium, nickel, chrome etc. as well as the whole range of different types of stainless steel. As the service life of the installations depend directly on the quality level of the welded joints, strict control and traceability of the weld process are required by customers, inspection bodies and standards authorities. For the assembly of one heat exchanger, hundreds or even thousands of faultless welds must be carried out, thus, in this area, orbital welding is invaluable in ensuring the expected results.
Fossil and nuclear power plants
For the safety of fossil fuel power stations and nuclear reactors, the whole range of orbital joining techniques are applied. Small diameter tubing must be connected, for sensing and control purposes, heat exchangers and other components are manufactured using orbital tube-to-tubesheet welding and thick-walled tubes for operation under high pressure and temperature must be assembled on site. The welding procedures and the weld quality are generally under constant surveillance by the respective authorities and external organisations. In this respect, the required complete documentation and traceability is ensured by the use of orbital equipment with its online data acquisition systems.
Principles & advantages of TIG welding
A summary of the TIG process
An electric arc is maintained between the non-consumable tungsten electrode and the workpiece. The electrode supports the heat of the arc; the metal of the workpiece melts and forms the weld puddle.
The molten metal of the workpiece and the electrode must be protected against oxygen in the atmosphere; an inert gas such as argon serves as shielding gas. If the addition of filler metal becomes necessary, filler wire can be fed to the weld puddle, where it melts due to the energy delivered by the electric arc.
Advantages
1 - Nearly all metals can be joined
2 - Different kinds of steel, including stainless steel, can be welded, as well as refractory or wear-resistant nickel alloys, aluminium, copper, gold, magnesium, tantalum, titanium, zirconium, and their alloys; even brass and bronze can be welded in certain cases. If filler wire is applied, workpieces consisting of dissimilar alloys or batches can also be joined together.
3 - All welding positions are possible
4 - The process is extremely stable and reliable, consequently, the occurrence of weld defects can be reduced to less than 1%
5 - No slag or fumes are produced during welding
6 - All weld parameters can be adjusted through a wide range, independently of each other
7 - TIG welding can be carried out with or without filler wire
8 - The arc voltage, which is directly related to the arc length, together with the weld current intensity, offer a wide range of variations and can be controlled automatically.
TIG Cold Wire
TIGer Hot Wire
TIG Hot Wire
Plasma Cold Wire
Принципы и преимущества сварки вольфрамовым электродом в среде защитного газа
BrauBeviale 2018 Trade Show in Nuremberg
The Brau Beviale trade show enables participants in the food industry — especially the beverage sector — to present their latest innovations across the production chain, from equipment installation to the finished product. This trade show will give Polysoude a chance to present its solutions for orbital pipe welding, developed through years of TIG process expertise, and above all the latest addition to its closed-head MW range.