TPi September 2018

Welding technology

Weld heads for thin stainless steel pipes HX series orbital weld heads from Orbitalum allow pipe elbows to be joined to small stainless steel pipes (for example in heat exchanger construction) with efficiency and reliability. Orbitalum is now expanding the series to include the HX 12P, which is designed for compact fin heat exchangers using pipe diameters from 9.5 to 13.3mm. around 30 seconds per pipe, and up to 250 welds per head and layer can be made in this way. While conventional heads and tongs require a lot of space between the pipes for positioning, the slim HX heads make it possible to build very compact heat exchangers with a high pipe density. Pipe spacing of less than 40mm is possible.

to call up the corresponding welding procedure and initiate the process prior to the start of welding. Working with the Orbitalum system is said to be so easy and reliable that even semi-skilled operators can achieve optimum welding results. Practice has shown that waste can be reduced from 4 per cent to under 0.7 per cent with the Orbitalum system. Another advantage of the system is that an operator can work with multiple weld heads at the same time, which increases production efficiency. The closed welding chamber and consistent process also prevent annealing colouration from occurring, so expensive reworking such as pickling and passivation can usually be dispensed with. In contrast to open welding tongs, all connections for power, gas and cooling water are integrated into the HX head. To facilitate handling, Orbitalum heads are connected to the welding power source with a flexible 7.5m hose. The HX 12P’s straight design enables easy turning of the head at the heat exchanger, and the entire unit can be suspended from a balancer to take the strain off the operator. In addition to the new HX 12P, the series includes the HX 16P for pipe diameters from 15 to 16.8mm, and the HX 22P for 18 to 22mm pipes. Orbitalum Tools GmbH – Germany

When performed by hand, the welding of pipe elbows for heat exchanger construction is an exhausting task. In addition, consistently high quality (and the proper sealing of all pipe elbows) on a continual basis by the welder cannot be guaranteed. This can result in expensive correction work and a lot of waste. The automated welding technology of HX orbital weld heads allows pre- mounted pipe elbows, even those in tight pipe bundles, to be welded reliably and quickly. Thin-walled stainless steel pipes with wall thicknesses of 0.5 to 0.8mm can be processed. It is claimed that preparation time is reduced by around 50 per cent, compared to manual work. The welding time is only

To operate, HX heads are opened up and placed around a pipe, and clamp themselves pneumatically at the push of a button. A stop with coarse and fine adjustment aids secure positioning on the pipe. Following the start-up procedure, the water-cooled head floods with argon gas and welding is carried out automatically. The Orbitalum system ensures clean weld penetration with no recesses, gaps or burrs in the pipe. Clamping and starting are activated by pressing buttons on the weld head. Orbitalum welding power supplies automatically detect the connected HX head and its specified parameters in such a way that the operator only needs

Photo credit: Orbitalum Tools GmbH

tools@orbitalum.com www.orbitalum.com

The slim HX heads allow the building of compact heat exchangers with high pipe density

Welding technology transforms productivity A new type of local vacuum electron beam welding technology developed in the UK by Cambridge Vacuum Engineering (CVE) is helping to revolutionise the power generation sector. The EBManPower project is a joint collaboration between CVE, U-Battery, Cammell Laird and TWI. smaller scale reactors, especially for developing countries and remote areas off main power grids. The current development of micro modular reactors presents a host of economic, industrial and environmental opportunities, contributing to the solution of what is known as the ‘energy trilemma’ (low carbon, secure and affordable energy), and enabling a low-carbon economy. £1.5mn, will implement and validate the first EBFlow system within a large- scale fabrication facility (in Birkenhead, UK) in order to enable cost-effective manufacture of large-scale power generation infrastructure. Cambridge Vacuum Engineering – UK

sales@camvaceng.com www.camvaceng.com EBFlow – UK www.ebflow.com

Large-scale nuclear reactors require high capital investment and rely heavily on the infrastructure of nuclear sites. The challenge has therefore been to develop

The EBManPower project, due to complete in 2021 at a value of

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TUBE PRODUCTS INTERNATIONAL September 2018

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