Solar flux is one flux cored wire is another.
Tig welding stainless steel pipe purging.
Crevice corrosion of the pipe.
This process also uses shielding gas against contamination but you can weld thinner metals more efficiently with it.
But the cost of the gas and the setup time for the purging process can be significant especially as the pipe diameters and lengths increase.
If you re welding stainless steel pipe with a traditional process like tig or stick it likely requires a back purge with argon gas.
Welding stainless steel tubes and pipes typically requires back purging with argon gas when using traditional processes such as gas tungsten arc welding gtaw and shielded metal arc welding smaw.
Purging during tig welding is a process that envelopes the weld area with a non reactive gas such as helium or argon minimizing oxidation of the base weld area.
I take it your talking about tig welded root runs.
Tig welding stainless steel is performed by using a non disposable tungsten electrode with a tig welder for striking up the arc.
There are six basic steps to purging a tig weld.
Aquasol water soluble paper provides an excellent barrier used to retain noble gases such as argon and helium within the weld zone during tig welding of stainless steel and aluminum pipes.
Solar flux is a powder that is mixed with methanol to form a cream like paste which is then painted onto the inside of the pipe plate.
There are a couple of ways to weld stainless steel without purging the back of the weld.
They are able to be placed within close proximity of the weld zone thereby increasing efficiency of the entire welding process.
Purge gas backing fluxes fight off oxygen purging stainless steel pipe with ar gon or nitrogen for 300 series alloys with less than 10 percent nickel re quires the purge gas to flow long enough to displace the air from the pipe and create an atmosphere of less than 1 percent oxygen.
At first you re required to appropriately configure your welder.
Prepare the pipe ends for welding.
Any welded stainless steel pipe application requires shielding the back of the weld as well as the front when tig welding.
When the laser welding process is chosen joints or welds being made on reactive materials will need to be carried out and in the case of electron beam welding this is carried out in a vacuum in which case purging takes place by complete evacuation of all gas.