Propylene (C3H6)


Propylene (C3H6) is a colourless fuel gas with a naturally pungent smell. Although similar to propane, it has a double bond which gives it a combustion advantage i.e. it burns hotter. This fuel gas is extremely flammable and non-toxic. Propylene is obtained during the refining of gasoline. But it can also be produced by splitting, cracking and reforming hydrocarbon mixtures.

Propylene is an attractive alternative to propane for heating and cutting due to its superior combustion performance. It is also widely used as a fuel gas for high-velocity oxygen fuel (HVOF) processes. In addition, the chemical and plastics industries rely on propylene as a fuel gas.

TEchnical Information

Molecular Weight 42.8
Specific Volume 8.9 cf/lb @ 70 F & 1 ATM
Flammability Limts in Air 2.4 - 11 % in Air
Liquid Density 4.325 lb / gal
Refrigerant Number R1270
Fill Density 44%

Safety Data Sheet PDF Link


Propylene Uses and Applications

Cutting: Propylene provides a faster cutting speed than acetylene, better quality of cuts meaning less grinding, and longer tip life.

Refrigerant: Propylene is used as a refrigerant in high/medium/low temperature applications including commercial refrigeration and air conditioning.

HVAC: Replace your “B” or “MC” tanks for identical tanks using Propylene.  Propylene provides more head and control for the demanding brazing and soldering applications. 

Calibration: Propylene is used as a component in calibration gases for the petrochemical/chemical industry.

Manufacturing: Propylene is polymerized to form polypropylene plastics.

Propylene Benefits vs Acetylene

Acetylene has long been the fuel gas of choice for cutting applications, but many welders are switching to an alternative fuel gas called propylene for increased safety and due to the fact that propylene often provides a significant cost savings over acetylene. In addition, propylene is generally considered safer and it provides increased flexibility because the cutting tip can be farther away from the work surface, while still resulting in an excellent cut. In this post we’ll be covering some of the common reasons to switch from acetylene to propylene to find out if it’s right for you.

Longer Lasting Cylinders – Increased productivity & lower labor costs
Each cylinder of propylene simply has more product than a cylinder of acetylene. For instance, a single 105lb propylene cylinder is equivalent to five, 330 cubic foot acetylene cylinders. This can significantly decrease both product and delivery costs as well as increase productivity because less time is spent changing out cylinders. According to a study completed by Gas Innovations, this can reduce labor of cylinder change outs by up to 80%.

Longer Lasting Cutting Tips – Lower costs
In general, cutting tip consumables last longer when using propylene. This is due to the fact that the tip-to-work distance is increased, so the tip is not exposed to such high temperatures or effects from the work surface. In addition, propylene cutting does not produce soot due to the chemistry of the gas that makes it a cleaner burning fuel.

More BTUs & Better Heat Transfer – Increased productivity and effectiveness
Using propylene for cutting results in more BTUs of heat for more effectively heating large parts and thick metals. Also, the chemistry of propylene results in better heat transfer properties than acetylene which means you can increase productivity by producing faster cuts.

Safety Benefits
When considering which fuel gas should be used, safety is at the top of the list. Propylene is generally considered a safer because it is a more stable gas. Acetylene’s stability issues with increased pressure can cause insufficient pressures for heating heads resulting in dangerous flashbacks. With propylene, this is only a very minimal concern.

Equipment Requirements
Most of the time, you only need to switch out the gas and cutting tips to begin using propylene for your cutting project as long as you’re already using a T-grade hose. In fact, any fuel gas other than acetylene requires the use of a T-grade hose because they are flame and oil resistant.

Ready? We’re here to help!
Tulsa Gas & Gear can provide nearly any equipment or gases for your specific application—whether you stick with time-tested acetylene, or you’d like to try out propylene. We’d love the opportunity to analyze your current application to see if propylene might be a good fit for you or your organization. If you’re interested in learning more about how propylene can be used to reduce your costs, and increase safety, contact us for more information or to request a live demo.


Propylene Transportation Information

Class or
Passenger Aircraft or
Railcar Quantity
Cargo Aircraft
Only Quantity
PropaneUN19782.1Not applicable2.1Forbidden150 kgN/A

Propylene Packaging Options

Low Pressure Cylinders

Low Pressure Bulk Tanks

Low Pressure Transport

Propylene Purity Grades

Instrument 99.50%
Chemically Pure (CP) 99.00%

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