Published on 27 March 2014
Electron beam (EB) welding is often used for its unique ability to produce low distortion welds in thick section materials in a single pass. To enable deep welding and ensure high integrity the process is carried out in a vacuum chamber which effectively limits the size and geometry of the assembly which may be welded. Component-specific static chambers can be used to maintain a vacuum local to the weld region but are inflexible and expensive to implement.
TWI's solution to this challenge is the mobile local vacuum sliding seal which is able to travel across a surface maintaining a vacuum only at the point of beam/material interaction. Today the technology, enabled in part by TWI's patented reduced pressure electron beam gun, has been applied to the welding of C-Mn steel plates of up to 60mm thickness and large tubulars of <2m diameter and 40mm wall thickness.
The technology is of interest for fabrication of large pressure containment vessels for conventional and nuclear power generation. These applications will be demonstrated during 2012 in thick section C-Mn and stainless steels. Another key driver for a move to EB welding is the increase in productivity which can be achieved through reducing time-consuming multi-pass welding and intermittent inspections.
For further information please see EB welding or contact us