A more thorough explanation:

Definition: A horsehead, also known as a pumping unit or pumpjack, is a piece of equipment used in the oil and gas industry to pump oil to the surface. It is used when the pressure difference between the formation and the borehole is not strong enough to cause oil to rise to the surface.

• A horsehead is typically made up of a large metal frame with a motor and a series of rods and pumps.
• When the motor is turned on, the rods and pumps move up and down, creating suction that pulls the oil to the surface.
• Oil wells that use horseheads can be found all over the world, from Texas to Saudi Arabia.

These examples illustrate how a horsehead works and where it is used in the oil and gas industry. The metal frame, motor, rods, and pumps all work together to create the necessary suction to bring the oil to the surface. Horseheads are used in oil wells all over the world, wherever the pressure difference between the formation and the borehole is not strong enough to bring the oil to the surface on its own.