Liquefied petroleum gases, such as propane and butane, have not been included as they are too numerous to mention.

The spherical tank is the storage of liquefied gases, and one of the commonly used pressure vessel, in the petroleum, chemical, metallurgical and city gas supply and so widely used.

Hydrogen can replace acetylene, gas, liquefied petroleum gases such as carbon, with high calorific value, flame concentration, zero pollution, high efficiency, energy saving and easy.