Welding Exhaust With Torch. It leaves a little room for expansion of the pipe and if you leave the top unwelded you can still grind it away and remove the pipe. Consequently should I weld my exhaust.
Local exhaust ventilation shall consist of freely movable hoods intended to be placed by the welder or burner as close as practicable to the work. Your base surface should be completely free of oils rust paint and dirt. In addition the influence of the angle of use of the welding torch was also investigated as part of the research at INRS.
Apply the flame to your weld.
Use on-torch extraction as this is the most effective fume control for MIG welding when it is set up and used correctly. A tig welder uses an electric arch to melt the metal and the torch uses flame. The pipe itself will reach temperature hot enough to weaken whatever solder used then vibrations will do the rest. Just a quick temporary repair.