Gas Cylinder

A gas cylinder is a pressure vessel built to store and contain gases above atmospheric pressure, typically shaped as an elongated cylinder with a flattened or dished base for standing upright and a shoulder and threaded neck at the top where a valve assembly attaches. Modern cylinders are built in four main types, ranging from all metal seamless steel or aluminum vessels, through metal cores wrapped in fiberglass or composite, to plastic liners fully wrapped in fiber reinforced composite. Contents may be stored as a compressed gas, as vapor over liquid, as a supercritical fluid, or dissolved in a substrate material, which makes gas cylinders a versatile way to store energy carrying gases for welding and cutting, breathing gas supply, liquefied petroleum and natural gas storage, medical gas delivery and laboratory use.