Does Argon Welding Gas Go Bad?

Welding Gas

A tank of gas usually lasts till it is fully empty without showing any signs of complications. Most people who work with argon mix daily; don’t face any problems while using it. But If a tank is left unused for a long time, complications may arise that inevitably leads to people suspecting whether the gas has gone bad or not.

Argon Gas, on its own, will never go bad nor lose any of its quality. However, the pressure in the gas tank can wane over time, causing various problems. You might occasionally find a bottle that has the wrong ratio of gas mixtures inside.

An average tank of argon gas for industrial usage holds up to 250 cubic feet of gas. It would take more than 10 hours of continuous welding for it to run dry. But does argon welding gas go bad? That’s highly unlikely. There are proper storage and mixing methods that can help you preserve the gas safely. As to what those methods are, I shall explain them below.

Argon Welding Gas Does Not Expire

Most of the time, argon 4.6 is the type that you are likely to see used in welding. It has a purity of around 99.96%. Depending on the metal, argon gas is mixed with other gases to simulate different bead profiles. As to when a tank of gas might expire; or go bad, nobody can tell.

Argon welding gas will not age and become defective with time. Here are some points that you should know regarding how argon gas behaves in storage conditions.

  • Impurities can affect performance

 If you take argon gas with a low purity level and store it in a container that has lost its temper, naturally, you’ll see bad results when trying to weld. The gas won’t go bad per se, but the cylinder’s impurities will interfere when you are welding.

  • Doesn’t change with time

Argon does not develop malicious characteristics in storage. No matter how long you keep it in a container, the gas will not start having weird reactions when you try to weld. If it is bad, it will show faults right at the start (impurities).

  • Mixed argon gas does not separate

There’s a common misconception that Argon mixed with other gases will separate in the bottle. The truth is that it does not. The molecular motion in a pressurized container does a pretty decent job of keeping mixed welding gas stay at the preferred consistency.

There might be some odd times that a new bottle of argon gas doesn’t work the way you know. That has nothing to do with the mixture inside being separated. The most likely cause of this might be from the manufacturer’s side. They might have mixed the wrong gases with Argon or messed up the ratio.

To reiterate, Argon gas won’t expire or lose its temper. But the impurities and addition of other gases can lower its performance when you weld. To avoid such problems, you should take extreme caution when filling or refilling a bottle of welding gas. Store it in a suitable container.

The Container May Develop Defects

Argon welding gas itself does not succumb to time and expire, but the container can most certainly lose its temperament. There’s no labeled expiration date on them, but extensive use can significantly lower its ability to store argon welding gas properly. That’s why large cylinders need checkups periodically to ensure their integrity.

If a gas container loses pressure for any reason, you cannot use the gas stored inside of it anymore. Gas tanks need to be inspected every three to ten years through a process called hydrostatic testing.

There are a few tips you can follow to keep your Argon gas containers from losing their temper.

Storage tips

There are a few common tips for storing any kind of welding gas. First off, make sure that the temperature of the storage area does not go over 125°.

Secondly, keep the bottle far away from direct sunlight. Lastly, keep the bottle upright. You do not ever want to drop a bottle sideways.

Routine inspection

 Keeping the gas bottles safe is only one part of the equation. The other part is regularly checking for indentations and punctures. Always check these things before starting to weld.

You should also check the valves and regulators to ensure their integrity. If you see any stuck valves do not immediately force them open. It is better to try lubricating the joints and slowly coax them open. Applying excessive force may damage the valves.

In all honesty, an argon gas bottle has more durability and lifespan than a regular human. A brand-new tank would last more than fifty years at the very least. As long as the bottles are handled properly, most people should not need to worry about these containers. But there are a lot of reusable tanks, so keeping track of age is kind of a hard thing to do.

Can You Refill Argon Welding Gas?

Yes, once your welding gas runs out, you can refill the bottle. The cost of a welding tank isn’t that low, so most people will keep refilling it rather than buying a new one. Usually, people would take their cylinder to a supply store and have them fill it up. The refilling process is simpler than you would think, and you can do it at home quite easily.

First, you would need a full cylinder. Usually, you can rent these things. Once you have them, the transfer process should be as follows:

  • Place the full cylinder beside the empty cylinder. One of them needs to be half-submerged into chilled water, so you also need to arrange for a large bucket.
  • Connect the two cylinders via a high-pressure copper line. Tight both ends of the line carefully to prevent gas leakage.
  • You need to connect a vacuum line that runs down to the vacuum gauge. Place it on the valve of the empty cylinder. Connect the other end of the vacuum line to a vacuum pump.
  • Run the vacuum pump at about three hundred to three hundred fifty milliliters. That should clean the residual gas out of the receiving cylinder. It also helps remove all the air from the copper line between the two cylinders.
  • Place the receiving cylinder in chilled water so that the pressure in the receiving cylinder falls. That will help draw more gas out from the other cylinder. If you place both cylinders at room temperature, the gas inside will not transfer. The pressure inside both cylinders would be the same, so there won’t be any push or pull effect.
  • Now shut down the vacuum pump and slowly open the main valve of the filled cylinder. Do this as gently as you can, and the gas should transfer into the receiving tank smoothly. And with that, you have successfully refilled an empty argon cylinder.


So, does argon welding gas go bad? I believe I clarified that it does not. The gas itself is not the problem, but you might occasionally face issues while welding due to the cylinders themselves wearing out with time and repeated use.  Check the content and ratio of the gas carefully if you are looking for a specific mix. Having a wrong ratio or wrong combination causing welding issues is not abnormal. If you figure it out early, your supply store should give you a refund or exchange it for a prop

Recent Posts