LPG Properties
LPG physical properties include specific gravity (density), boiling point, pressure, vapour expansion, energy content, combustion facts, flame temperature, flash point & more.
This chart shows some of the physical properties of propane, butane and isobutane…
LPG Pressure Varies with Temperature
- As previously mentioned, when LPG is stored in a gas bottle, it is under pressure.
- The term “pressure” refers to the average force per unit of area that the gas exerts on the inside walls of the gas bottle.(LPG Pressure-Temperature Chart shown)
- Pressure is measured in kilopascals (kPa) or pounds per square inch (psi).
- LPG pressure can vary greatly based on temperature, as shown in the chart.
- The level of fill in the gas bottle comes into play when the LPG is being used, as it affects the rate of vaporization.
- As LPG is a liquefied gas, the pressure inside the cylinder will remain the same from full until the last of the liquid LPG is vaporized.
- Then the pressure will fall quickly as the last of the LPG vapour is used, as well.
LPG is Heavier Than Air
- In answer to the frequently asked question "Is LPG heavier than air", the answer is "YES".
- For example, if the density of air is equal to 1.00, the density of propane is 1.53.
- Butane is even heavier, at 2.00. Isobutane is heavier still, at 2.07.
- On the other hand, natural gas - methane - is lighter than air, at about 60% of the density of air.
