The Drill Bit A drill bit is the cutting tool used in drilling. Once geologists have decided where to drill, the next step is to make a hole. A drill bit rotates in the ground, gouging and scraping away the rock. Modern drill bits come in many shapes and sizes. The most basic drill bit used today is the roller cone bit. Each cone rotates separately, digging its teeth into the rock. Nozzles in the drill bit allow drilling fluid or mud to jet out, washing away cuttings and carrying them to the surface.

Hydrocyclone Separator Crude oil from the reservoir may contain sand and other unwelcome solid particles. One means of removing these particles from the oil is a vortex separation or hydrocyclone.
Oil carrying particles enters the top of separator. The shape of the separator causes the oil to move in a spiral path, like the air in a tornado. The rotating motion creates centripetal force, keeping the oil in the center of the cyclone while the particles move out to the sides. The clean oil exits through the top of the separator.

Christmas Tree A Christmas tree is a group of valves used to control the flow of fluids from a completed well.
Through a small stretch of the imagination, the Christmas tree may resemble its namesake. Tubing from the well is connected to the Christmas tree. Since natural gas is lighter than air and under tremendous pressure, it flows up the well without the need for pumps. Valves and chokes on the Christmas tree control the flow of the natural gas. A choke is a device with a small opening in it used to regulate the flow. Some valves allow sampling of the natural gas stream. Pressure gauges indicate the flow pressure of the gas. After leaving the Christmas tree, the gas goes to other treatment equipment in the field.