The Cameron ram-type blowout preventer was the first successful blowout preventer (BOP) for oil wells. It was developed by James S. Abercrombie and Harry S. Cameron in 1922. [1] [2] The device was issued U.S. patent 1,569,247 on January 12, 1926. [3] The blowout preventer was designated as a Mechanical Engineering Landmark in 2003. [1] [2] [4]
While drilling an oil or gas well, the top of the wellbore is lined with a casing. The drill string runs through the casing. The annular (ring-shaped) region between the casing and the drill stem is filled with drilling mud which provides hydrostatic pressure to keep the formation fluid from coming up the wellbore. If the pressure of the formation fluid exceeds the hydrostatic pressure of the drilling mud, the oil or gas can blow out of the wellbore. This has caused spills of large quantities of oil and fires on drilling rigs. The blowout of the Lucas well at the Spindletop field in 1901 lasted for over nine days and spilled over 500,000 US barrels (60,000,000 L; 16,000,000 US gal; 13,000,000 imp gal) of oil. [4]
James Smither Abercrombie (1891–1975), a Texas oil driller, and Harry S. Cameron (1872–1928), who operated a machine shop, formed the Cameron Iron Works in 1920. [5] Abercrombie had an idea for a blowout preventer and took it to Cameron. They designed and built the device at the Cameron Iron works. This resulted in the first ram-type blowout preventer, which they called the MO BOP. [1] [2] [4]
Cameron Iron Works successfully marketed their blowout preventer and developed other tools for petroleum exploration. In 1990, Cooper Industries acquired the company. Cooper's petroleum divisions were transferred into the Cooper Cameron Corporation. [4] This company is now called Cameron International Corporation.
The blowout preventer is a T-shaped coupling that is screwed onto the top of the casing. It has a passage through the coupling for the drill string. There is a ram with a concave, semi-circular face in each arm of the tee. Each ram is moved in or out by turning its valve stem, which extends beyond the coupling. The ends of the stems are squared off. [3]
When the rams are retracted, there is a passage for the drilling mud. If a blowout begins, the drill string is stopped. Then wrenches are used to manually close the rams around the drill string to seal the wellbore. [3] The MO BOP was tested to withstand 3,000 pounds per square inch (21,000 kPa). [1]
The device had a lateral valve below the rams on its bottom section. In case of a blowout, a mud pump could be used to pump drilling mud into the wellbore to control the blowout. [3]
In the oil and gas industry, the term wireline usually refers to the use of multi-conductor, single conductor or slickline cable, or "wireline", as a conveyance for the acquisition of subsurface petrophysical and geophysical data and the delivery of well construction services such as pipe recovery, perforating, plug setting and well cleaning and fishing. The subsurface geophysical and petrophysical information results in the description and analysis of subsurface geology, reservoir properties and production characteristics.
Well control is the technique used in oil and gas operations such as drilling, well workover and well completion for maintaining the hydrostatic pressure and formation pressure to prevent the influx of formation fluids into the wellbore. This technique involves the estimation of formation fluid pressures, the strength of the subsurface formations and the use of casing and mud density to offset those pressures in a predictable fashion. Understanding pressure and pressure relationships is important in well control.
Casing is a large diameter pipe that is assembled and inserted into a recently drilled section of a borehole. Similar to the bones of a spine protecting the spinal cord, casing is set inside the drilled borehole to protect and support the wellstream. The lower portion is typically held in place with cement. Deeper strings usually are not cemented all the way to the surface, so the weight of the pipe must be partially supported by a casing hanger in the wellhead.
A wellhead is the component at the surface of an oil or gas well that provides the structural and pressure-containing interface for the drilling and production equipment.
In geotechnical engineering, drilling fluid, also known as drilling mud, is used to aid the drilling of boreholes into the earth. Used while drilling oil and natural gas wells and on exploration drilling rigs, drilling fluids are also used for much simpler boreholes, such as water wells.
A blowout is the uncontrolled release of crude oil and/or natural gas from an oil well or gas well after pressure control systems have failed. Modern wells have blowout preventers intended to prevent such an occurrence. An accidental spark during a blowout can lead to a catastrophic oil or gas fire.
A blowout preventer (BOP) is a specialized valve or similar mechanical device, used to seal, control and monitor oil and gas wells to prevent blowouts, the uncontrolled release of crude oil or natural gas from a well. They are usually installed in stacks of other valves.
Underbalanced drilling, or UBD, is a procedure used to drill oil and gas wells where the pressure in the wellbore is kept lower than the static pressure of the formation being drilled. As the well is being drilled, formation fluid flows into the wellbore and up to the surface. This is the opposite of the usual situation, where the wellbore is kept at a pressure above the formation to prevent formation fluid entering the well. In such a conventional "overbalanced" well, the invasion of fluid is considered a kick, and if the well is not shut-in it can lead to a blowout, a dangerous situation. In underbalanced drilling, however, there is a "rotating head" at the surface - essentially a seal that diverts produced fluids to a separator while allowing the drill string to continue rotating.
In the oil and gas industry, coiled tubing refers to a long metal pipe, normally 1 to 3.25 in in diameter which is supplied spooled on a large reel. It is used for interventions in oil and gas wells and sometimes as production tubing in depleted gas wells. Coiled tubing is often used to carry out operations similar to wirelining. The main benefits over wireline are the ability to pump chemicals through the coil and the ability to push it into the hole rather than relying on gravity. Pumping can be fairly self-contained, almost a closed system, since the tube is continuous instead of jointed pipe. For offshore operations, the 'footprint' for a coiled tubing operation is generally larger than a wireline spread, which can limit the number of installations where coiled tubing can be performed and make the operation more costly. A coiled tubing operation is normally performed through the drilling derrick on the oil platform, which is used to support the surface equipment, although on platforms with no drilling facilities a self-supporting tower can be used instead. For coiled tubing operations on sub-sea wells a mobile offshore drilling unit (MODU) e.g. semi-submersible, drillship etc. has to be utilized to support all the surface equipment and personnel, whereas wireline can be carried out from a smaller and cheaper intervention vessel. Onshore, they can be run using smaller service rigs, and for light operations a mobile self-contained coiled tubing rig can be used.
A well kill is the operation of placing a column of special fluids of the required density into a well bore in order to prevent the flow of reservoir fluids without the need for pressure control equipment at the surface. It works on the principle that the hydrostatic head of the "kill fluid" or "kill mud" will be enough to suppress the pressure of the formation fluids. Well kills may be planned in the case of advanced interventions such as workovers, or be contingency operations. The situation calling for a well kill will dictate the method taken.
Snubbing is a type of heavy well intervention performed on oil and gas wells. It involves running the BHA on a pipe string using a hydraulic workover rig. Unlike wireline or coiled tubing, the pipe is not spooled off a drum but made up and broken up while running in and pulling out, much like conventional drill pipe. Due to the large rigup, it is only used for the most demanding of operations when lighter intervention techniques do not offer the strength and durability. The first snubbing unit was primarily designed to work in well control situations to "snub" drill pipe and or casing into, or out of, a well bore when conventional well killing methods could not be used. Unlike conventional drilling and completions operations, snubbing can be performed with the well still under pressure. When done so, it is called hydraulic workover. It can also be performed without having to remove the Christmas tree from the wellhead.
Well completion is the process of making a well ready for production after drilling operations. This principally involves preparing the bottom of the hole to the required specifications, running in the production tubing and its associated down hole tools as well as perforating and stimulating as required. Sometimes, the process of running in and cementing the casing is also included. After a well has been drilled, should the drilling fluids be removed, the well would eventually close in upon itself. Casing ensures that this will not happen while also protecting the wellstream from outside incumbents, like water or sand.
Oilfield terminology refers to the jargon used by those working in fields within and related to the upstream segment of the petroleum industry. It includes words and phrases describing professions, equipment, and procedures specific to the industry. It may also include slang terms used by oilfield workers to describe the same.
In oil or gas well drilling, lost circulation occurs when drilling fluid, known commonly as "mud", flows into one or more geological formations instead of returning up the annulus. Lost circulation can be a serious problem during the drilling of an oil well or gas well.
Oil well cementing equipment are essential for oil and gas exploration and are required oilfield equipment when drilling a well.
Offshore oil spill prevention and response is the study and practice of reducing the number of offshore incidents that release oil or hazardous substances into the environment and limiting the amount released during those incidents.
Oil well control is the management of the dangerous effects caused by the unexpected release of formation fluid, such as natural gas and/or crude oil, upon surface equipment of oil or gas drilling rigs and escaping into the atmosphere. Technically, oil well control involves preventing the formation gas or fluid (hydrocarbons), usually referred to as kick, from entering into the wellbore during drilling or well interventions.
The Deepwater Horizon investigation included several investigations and commissions, among others reports by National Incident Commander Thad Allen, United States Coast Guard, National Commission on the BP Deepwater Horizon Oil Spill and Offshore Drilling, Bureau of Ocean Energy Management, Regulation and Enforcement, National Academy of Engineering, National Research Council, Government Accountability Office, National Oil Spill Commission, and Chemical Safety and Hazard Investigation Board.
James Abercrombie was an American inventor who is best known for designing the world's first reliable blowout preventer (BOP) to contain disastrous well blowouts.
