Christmas tree (oil well)

A Christmas tree (short: E- Cross, English Christmas Tree. ) Serves as borehole completion of a successful drilling for oil or gas. It consists of a flanged pipe and several fittings, pressure gauges and fittings, which are permanently connected to the casing of the well. With this arrangement, it is possible to remove the imminent oil and gas in the well controlled and to feed a pipeline.

The Christmas tree is also used in drilling, pumping water and other liquids or gases into the wellbore, for example, to increase the pressure in the associated oil field or introduce natural gas into a tapped by drilling underground storage.

• Petroleum extraction technique