Christmas tree (oil well)

In petroleum and natural gas extraction, a Christmas tree, or tree, is an assembly of valves, casing spools, and fittings used to regulate the flow of pipes in an oil well, gas well, water injection well, water disposal well, gas injection well, condensate well, and other types of well. == Overview == The first primitive Christmas tree was used by the Hamill Brothers to bring Spindletop under control.

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