Doug Perry

As you know when it comes to oxy-fuel applications the "Holy Grail" is Hydrogen.  The burning of H2 and O2 results in only two by-products - energy release in the form of heat and plain old pure water - H²O.

You cannot find a more abundant, more renewable source of energy.  Hydrogen is actually the most abundant substance in the universe, and Oxygen too is very abundant.  In fact, if you separate water into H2 and O2, then recombine it by burning, it returns to water, and our planet has more water than dirt.  Oxy-hydrogen is truly "green."  The only real problem is that it takes too much energy to separate water into Hydrogen and Oxygen to make its energy competitive with the other fuel gases out there now. So being abundant is not reflected in its price.

The use of Oxy-hydrogen fuels is not new to our industry.  In the past Hydrogen was the fuel of choice for things like underwater cutting and special welding applications like welding aluminum or lead. 

Currently we still use Oxy-hydrogen when we need a flame devoid of contaminants like the carbon emitted from the combustion of ordinary hydrocarbon fuels.  Forming laboratory glass, polishing plexi-glass, and melting precious metals are common uses of Oxy-hydrogen flames today.  So if you need a really clean flame, use an Oxy-hydrogen flame.

Officially Harris recommends using equal pressure Acetylene-oxygen equipment for Oxy-Hydrogen applications - with one exception: you'll need a regulator with a 350 CGA on a Hydrogen cylinder.  A 350 is generally for high pressure fuel gases (>500 psig) versus the more common CGA 510 connection meant only for low pressure fuel gas cylinders. You can use an Acetylene Tip Chart to set the gas pressures.  Even though Hydrogen is much thinner than Acetylene gas and it requires using a very different oxy-fuel ratio, everything seems to work itself out and you'll end up with a hot, clean, stable flame. 

When you get the flame going, the first thing you'll notice is that the flame is pale, with hardly any color.  The fact is that there is virtually no carbon in the flame to give it the color and intensity you are used to when burning hydrocarbon fuels.  This makes the flame difficult to see in daylight or in a brightly lit room. So be careful, there are a few things more dangerous than a flame that you cannot see.
In addition to its flame being hard to see there are two other negatives you will become aware of if you choose to give it a try: first, it is usually more expensive than the other alternate fuels and second, it has a greater tendency to leak. It tends to leak because along with being the most abundant substance in the universe, it is also the thinnest. Remember: CHECK FOR LEAKS TWICE - LIGHT ONCE!

Summary:

• Use Oxy-Hydrogen through Equal pressure Oxy-Acetylene Torches, Mixers and Tips.
• Exchange Acetylene low pressure regulators for a high pressure Hydrogen regulators – CGA 350.
• Set pressures the same as those found in Acetylene Tip Charts
• Warning: 
• Flame will be virtually invisible.
• Hydrogen has great potential for leaks – check thoroughly and only use in well-ventilated areas.