Mild Steel Tubes and Purging

Mild steel welds can be quite difficult to get right ifon the purging process. This is due to the
you are not used to this kind of work. It can be onecomponents of water which are hydrogen and
of the most difficult jobs to do when working withoxygen. Wait until all the water will evaporate.
mild steel tubes. Hats off, if you can do it well, but it2. You can poke a small hole at the topmost part of
takes a real man to be able to do this job. You willthe tube to allow the argon gas to flow continuously
need to wait for the mild steel tube to cool afterinside it. Argon should freely flow inside the tube to
interval passes, while making sure that you keep thelet all the air out of the tube, as argon is denser than
tip extremely hot and shielded with argon. You alsoair. Argon will also remove air out of the tube
have to make sure that you snip the tip of thebecause it has the ability to displace it.
welding rod if it ever gets crapped up so as to keep3. Use a diffuser and place it at both ends of your
your tungsten sharp as it should be.argon hose to ensure a higher flow rate of the gas.
Purging steel is a very tough thing to do. Mild steelA homemade diffuser can be easily fabricated with
tubes and all the other types of stainless steelusing stainless steel wool, perforated stainless steel
products need to be purged with argon gas tosheet and small piece of sheet metal.
prevent them from sugaring or granulation, which isIf you are sure that a good purge was done, you
the effect of severe oxidation.can proceed with tacking. You can do this by getting
Mild steel welds cannot be complete without an argonthe tape off to let the tack cool down, after which
purge on the inside surface of common mild steelyou should re tape it. The tacking should be done 180
tube. And this process is done by wrapping aluminumdegrees apart.
duct tape around the ends of the mild steel tubesThere are more tips that you can follow when
while argon gas is left to be trapped inside it.welding stainless steel pipe.
To be able to determine whether the tube has been1. Instead of using a 3/32 inch rod, you should use a
purged enough, you need to use an oxygen analyzer;1/8 inch wire to do better welding.
and to make sure that you do a good purge, here2. Re-welding can be done on impenetrable areas.
are some tips that you can follow:3. Prefer to use stainless steel wire brushes and files
1. Check that there is no water left inside in mild steelwhich are for stainless steel alone.
tube. Even a single drop of water will cause damage4. To avoid overheating, use enough amperage.