Oxy-Fuel Cutting with Propylene
When fuels are burned in the presence of oxygen, they are able to generate a flame of a higher temperature compared to that of a fuel burned in air. Oxy-fuel cutting makes use of this extremely hot flame to cut metals and it is up to the operator to select the fuel they will use. Acetylene, propylene, and propane are all common fuels that are used, and, specifically, propylene offers the cutter the safest, cheapest, and most efficient means of cutting.
Benefits of Propylene for Cutting
To explain the benefits of propylene, it is helpful to understand how it differs from acetylene gas. Acetylene is a popular choice among oxy-fuel cutters because if burns with the hottest flame and also allows for oxy-fuel welding. The downside of acetylene as a fuel is its volatility. The explosive potential of acetylene means that it must be stored in expensive tanks and its delivery pressure is limited which limits the overall heat output of the flame.
In contrast, propylene is far more stable than acetylene and, therefore, the storage is safer and the price per cylinder is lower. Another advantage of propylene is the high overall heat output. Although acetylene burns at a higher primary temperature, it is limited to a pressure of 15 psi, a limitation that propylene does not have. Therefore, propylene work can work at a higher pressure which more than makes up for the lack of initial heat in terms of overall energy output. This quality makes propylene especially effective for heating and cutting large or thick pieces of metal.
Propylene Stability
Safety was previously mentioned and it is a major concern of people who work with acetylene. All compressed gas cylinders should be treated with great care and stored under precaution, but acetylene is especially sensitive. Because acetylene is so unstable, it must be stored in liquid acetone and, as stated, is limited in its output. Propylene is more stable under pressure, thus less likely to cause an accidental. Plus, due to the lower flame temperature, propylene cuts with less splatter which is safer for the operator and makes a cleaner cut.
Equipment Considerations for Propylene Cutting
Finally, important consideration must be given to the equipment used when oxy-fuel cutting with propylene. First, an injector torch is needed to achieve the optimal cutting flam and a grade “T” hose is needed to deliver the gas. (Grade T ensures that the hose does not degrade) Secondly, an 8-hole tip is needed to cut with propylene, as opposed to the 4- to 6-hole tips of acetylene set ups.
Propylene Cutting is Cost Effective
Apart from the initial investment in new equipment, oxy-fuel cutting is actually less expensive than acetylene. That is because propylene gas itself is less expensive than acetylene and increasing in price at a much slower rate. Weigh the advantages and disadvantages of propylene gas for oxy-fuel cutting with your budget and cutting needs to figure out if propylene is the right gas for you.
