Blowout Preventer (BOP)
Definition - What does Blowout Preventer (BOP) mean?
A blowout Preventer is a set of specialized valves installed on the well head in stacks, which are used to control the flow of gases or liquids from the well during drilling and production operations. BOP system is mainly operated during the situations of a well kick.
This term is usually interchanged with blowout preventer stack, blowout preventer system and it is abbreviated as BOP (“B-O-P”).
Petropedia explains Blowout Preventer (BOP)
When drilling a well, mud system is a primary barrier and a BOP system is a secondary barrier for well control. When the primary barrier fails, hydrocarbons may enter the wellbore and a kick will occur. To gain control on this situation the drilling crew will operate the BOP system to close.
BOP is of two types- Annular and RAM type which comes in different sizes and pressure ratings. This is installed on top of the well head in stacks and allows access to the formation. They are designed to close the bore hole completely when there is no string in the well, allow closing of the well with the string (Drill pipe, Tubing etc.) inside and few are designed to shear or cut the string. BOP is a major equipment for safety of the rig and personnel, so they are inspected regularly and pressure tested every 21 days as per standards. On jack up rigs BOP is mounted below the rotary while in floater they are installed on surface of sea bed.
Functions of BOP:
- Control the flow of well fluids.
- Allow pumping of fluids into well.
- Monitor the wellbore pressure and allow to bleed of excess pressure.
- Shut in the well, i.e., seal the annular space between drill pipe and casing.
- Completely seal the well bore and shear the string.