Hydrogen Refill
As a fuel gas with oxygen, hydrogen produces a relatively low flame temperature of 5,125°F (2,830°C) and it is most useful for the brazing of aluminum and magnesium and for lead welding. Because hydrogen can be safely compressed to overcome underwater pressures, oxyhydrogen cutting torches are sometimes employed by divers on salvage operations. Mixed in small quantities with argon, hydrogen brings significant improvements in weld quality for stainless steels. Hydrogen is also increasingly used in plastic brushing applications.