Blowout Preventers

Blowout Preventer (BOP) devices are typically installed on the top of the casing, below the rig floor. BOPs are large valves that help contain the liquid and gas pressure in the well. 

One type of BOP can seal off the annulus, the space between the drill pipe and the casing, if the drill pipe is still in the hole. Another can shear off the drill pipe and thus seal off the entire well if no drill pipe is in the hole. Usually, several of these BOPs are mounted as a BOP stack. 

Read more about the role of Blowout Preventers in the Stages of Drilling!

Petroleum Communication Foundation. Our Petroleum Challenge: Exploring Canada's Oil and Gas Industry, Sixth Edition. Calgary: Petroleum Communication Foundation, 1999. With permission from the Petroleum Communication Foundation.