Annular-type Blowout Preventer

annular blowout preventer

A drilling rig works efficiently due to all its components. Wellhead equipment, blowout preventers, mud pump, pipe ramp etc are some of the important components of any drilling rig. Of the above mentioned components, blowout preventer is one of the fundamental components. BOP is a special type of valve which deals with extreme pressures that can lead to explorations. The sub-types of blowout preventers are used to seal the wellhead to stop the flow of fluid (oil) from the wellbore. Ram BOP and annular BOP are the two types of BOPs. The major difference between the two is between the techniques used to function. One advantage of annual blowout preventer is that an annual blowout preventer can seal various types of pipes, unlike the ram BOP.

Annular BOP was invented in 1946 by Granville Sloan Knox. It is a large valve that is installed about the ram blowout preventer and seals in the annular space between the wellbore and the pipe. This type of BOP is used for on-shore as well as off-shore operations. Though the annular blowout preventer was invented in the year 1946, a patent was awarded to Knox in 1952. The annular BOP invented by Knox, was later modified for subsea BOP stack use. One of the modified version that was rewarded a patent was designed by Ado N. Vujasinovic. This variation of the original BOP is now counted as a type of annular-type BOP known as the spherical blowout preventer.

The original type of annular blowout preventer uses a conical-faced piston for functioning. When this piston rises, the movement of the packing unit is restricted, making the piston squeeze inward towards the middle of the wellbore. It also has a rubber seal element, which helps to seal the space between drill collar, kelly or drill pipe.

Spherical blowout preventers are named so due to its shape. These blowout preventers can provide pressure for moving the pipe in and out of the hole. The spherical BOPs manufactured now a days are compact, so are able to seal any kind of drill pipe, casing and so on.

Every blowout preventer stack at least has one annular BOP. An annular blowout preventer is generally used to seal the drill stem in the hole, however, if there is no drill stem, it can close over the open hole. These are some of the common features of every annular BOP; however, most of the oil drilling equipment manufacturers have some special features for the products manufactured by them. Like at Integrated Equipment, we design annular BOPs that are strong yet simple in construction. We also use trash rings to avoid debris from dropping into the chambers during field replacement of packing rubber.

Ram and annular blowoutpreventers manufactured by us meet all the requirements of API 16A. For reliable and long-lasting oil drilling products, those are accredited per ISO 9001; Integrated Equipment is the right choice.