X-Tree

The term "X-Tree" in the context of the oil and gas industry typically refers to an "Christmas Tree" or "Wellhead Tree." A Christmas Tree (X-Tree) is an assembly of valves, spools, and fittings used for controlling the flow of oil or gas from a well. It is an essential component in the production and exploration of oil and gas wells. These trees are installed on top of the wellhead and provide a means to:

Control the flow of hydrocarbons (oil and gas) from the well.
Monitor and regulate well pressure and temperature.
Inject chemicals or other substances into the well.
Secure the well in case of emergencies.