MAG welding – Which gas is required?
- This article provides information about MAG welding and the shielding gases used in itComposition of shielding gasesThe different sizes of gas cylinders / delivery formsPossibilities Suppliers, sources of supply etc.Leak test Gas supplyHow long does my gas cylinder last
Mag welding gas / inert gas
The term MAG welding already includes active gas in the abbreviation metal,
a reference to the shielding gas. So a
active gas, in former times mostly pure carbon dioxide was used, today there are rather gas mixtures. Mostly the standard is a mixture of argon and carbon dioxide.
The standard user looks for a gas dealer, this can even be a hardware store today and buys the gas mixture available there.
For example Corgon, Sagox or others are common products.
It should always be noted that the shielding gas must always match the material and the filler metal.
Corgon & Sagox are for example gases for carbon steel, construction steel etc.
bottle size / delivery form
The following bottle sizes are normally available: 10, 20, 33 and 50 litres.
The pressure is normal at 200 bar on delivery, at 20 degrees Celsius of course only.
Temperature is an important factor, many manufacturers report that in winter customers regularly complain that the bottle has less content, i.e. less pressure. This is of course due to the lower temperature, but in return nobody complains in summer when the bottle is over 200 bar.
Latest generation cylinders have 300 bar, in addition they have an integrated pressure reducer and an integrated pressure gauge. Even cylinders with RFID chip and GPS, so that the cylinders can be found and recognized again and again, are already available or are in planning by the manufacturers.
The normal hobby user will be well served with a 10 or 20 litre bottle. The 10 and 20 litre bottles are easy to transport, so they are much more mobile than large bottles.
MAG welding gas / sources of supply
Likes welding gas / sources of supply or simply said where do I get my gas from. Besides many gas traders, more and more DIY stores supply technical gases such as argon, but also argon carbon dioxide mixtures. So exactly what we need for MAG welding. There are also online shops that ship gas cylinders at low prices, I have already ordered here, for example. Click here
Disposable bottles, such as this one (to the disposable bottle), can also be a cheap alternative. Especially for occasional users who only need small quantities.
Many manufacturers offer e.g. rental bottles, but this is usually only worthwhile for regular users. For occasional welders, it is better to buy a gas cylinder, which is usually offered by DIY stores. The empty bottle can then be exchanged for a new one. For a 10 or 20 litre bottle you have to calculate between 100 and 130 Euros, plus of course the filling. A filling should cost between 30 and 40 euros. But also online shops offer recently good service in this area. Always inform before about exchange refill and return of the empty bottle.
In addition to the gas cylinder, the pressure reducer is an important aspect of the gas supply during welding.
The pressure reducer reduces the cylinder pressure to the required working pressure. The required working pressure for MAG welding is usually determined by the wire thickness to be welded or the diameter of the welding wire.
10 to 12 litres are standard here.
In addition, the pressure reducer offers a pressure gauge from which the filling level of the bottle can be read
An important point in gas supply is always the tightness in the following video you can see a short simple but very effective tightness test. Such a short test should be standard, because first of all shielding gas is expensive and secondly it is always very annoying when welding tasks are pending and the required shielding gas is missing or almost empty. So regularly test or check the tightness of the gas supply.
How long does my gas bottle
A standard question how long does my gas bottle last, we have three factors: the size of the gas bottle, the pressure of the gas bottle and the amount of gas extracted in litres per minute. Now we can easily calculate how long our gas bottle will last.
A theoretical example:
10 litres x 200 bar = 2000 litres 10 litres per minute Consumption 2000 litres/ 10 litres per minute = 200 minutes
This means that welding can be carried out continuously for 200 minutes. Losses and leaks are not taken into account in this calculation.
Nevertheless a good answer to the question: How long will my gas bottle last?