Tandem SAW Narrow groove application
As the section thickness of vessel for nuclear and petroleum industry increase, the desire
for reduced weld time and material consumption has driven the joint on these vessels to
become narrower joint significantly reduce number of passes and material needed to
complete each joint. Whenever material and specification allow, SAW process ideally
Tandem with two torches are is preferred due to its ability to provide higher strength. Itprevents undercut, trapped slag and concave profile since there are maximum two passes
per layer. It is required to change mode of power supply from DC to AC when switching
from root pass to filler pass.
TWIN HEAD-SAW – In order to increase productivity of welding two wire or multi wire
SAW process is carried out. LNT practice that for many of high thickness nuclear pressure
vessel.