blowout preventer manufacturers usa

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blowout preventer manufacturers usa
WHAT IS BOP - KNOW EVERYTHING IN DETAIL
Blowout preventers come in a variety of styles, sizes and pressure ratings. Several individual
units serving various functions are combined to compose a blowout preventer stack. Multiple
blowout preventers of the same type are frequently provided for redundancy, an essential factor
in the effectiveness of protective devices.
The Primary Functions Of Blowout Preventer system are to:●
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Confine well fluid to the wellbore;
Provide means to add fluid to the wellbore;
Allow Control volumes of fluid to be withdrawn from the wellbore;
Regulate and monitor Wellbore pressure;
Centre and hanging of the drill string In the Well bore;
Shut in the well (e.g. seal the void annulus, between drill pipe and casing);
“Kill” the well (prevent the flow of formation fluid, influx, from the reservoir into the
wellbore) ;
Seal the wellhead (close off the wellbore);
Sever the casing or drill pipe (in case of emergencies).
In drilling a typical high-pressure well, drill strings are routed through a blowout preventer stack
toward the reservoir of oil and gas. As the well is drilled, drilling fluid, "mud", is fed through the
drill string down to the drill bit, "blade", and returns up to the wellbore in the ring-shaped
void, annulus, between the outside of the drill pipe and the casing (piping that lines the
wellbore).
The column of drilling mud exerts downward hydrostatic pressure to counter opposing force
from the formation being drilled, allowing drilling to proceed. This is less desirable because of
the higher surface pressures likely needed and the fact that much of the mud originally in the
annulus must be forced into receptive formations in the open hole section beneath the most
in-depth casing shoe.
Types
Ram blowout preventer
The Ram BOP was invented by James Smither Abercrombie and Harry S. Cameron in 1922
and was brought to market in 1924 by Cameron Iron Works. A ram-type BOP is similar in
operation to a gate valve but uses a pair of opposing steel plungers, rams. The rams extend
toward the centre of the wellbore to restrict flow or retract open in order to permit flow. The inner
and top faces of the rams are fitted with packers ​(​elastomeric seals) that press against each
other, against the wellbore, and around tubing running through the wellbore.
Rams, or ram blocks, are of four common types: ​pipe​, ​blind​, ​shear​, and ​blind shear​.
Annular blowout preventer
The Annular blowout preventer was invented by Granville Sloan Knox in 1946; a U.S. patent for
it was awarded in 1952. Often around the rig, it is called the "Hydril", after the name of one of
the BOP manufacturers.
An annular-type blowout preventer can close around the drill string, casing or a non-cylindrical
object, such as the kelly. Drill pipe including the larger-diameter tool joints (threaded
connectors) can be "stripped" through an annular preventer by careful control of the hydraulic
closing pressure. Annular blowout preventers are also effective at maintaining a seal around the
drill pipe even as it rotates during drilling. Regulations typically require that an annular preventer
be able to completely close a wellbore, but annular preventers are generally not as effective as
ram preventers in maintaining a seal on an open hole.
Control Methods
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Hydraulic Control Signal: sent from the surface through a hydraulic umbilical.
Electrical Control Signal: sent from the surface through a control cable.
Acoustical Control Signal: sent from the surface based on a modulated/encoded pulse of
sound transmitted by an underwater transducer.
ROV Intervention remotely operated vehicles (ROVs) mechanically control valves and
provide hydraulic pressure to the stack (via “hot stab” panels).
Top ​Blowout Preventer manufacturers USA
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Schlumberger
National Oilwell Varco
Baker Hughes
Worldwide Oilfield Machine, Inc.
Control Technology Inc.
To know more visit our ​website​.
Conclusion
Since BOPs are essential for the safety of the crew and natural environment, as well as the
drilling rig and the wellbore itself, authorities recommend, and regulations require, that BOPs be
regularly inspected, tested and refurbished. Tests vary from daily analysis of functions on critical
wells to monthly or less frequent testing on wells with a low likelihood of control problems.
Exploitable reservoirs of oil and gas are increasingly rare and remote, leading to increased
subsea deepwater well exploration and requiring BOPs to remain submerged for as long as a
year in extreme conditions.

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