Gulf of Mexico

You may have heard the news in the last two days about the Deepwater Horizon drilling rig which caught fire, burned for two days, then sank in 5,000 ft of water in the Gulf of Mexico. There are still 11 men missing, and they are not expected to be found.

The rig belongs to Transocean, the world’s biggest offshore drilling contractor. The rig was originally contracted through the year 2013 to BP and was working on BP’s Macondo exploration well when the fire broke out. The rig costs about $500,000 per day to contract. The full drilling spread, with helicopters and support vessels and other services, will cost closer to $1,000,000 per day to operate in the course of drilling for oil and gas. The rig cost about $350,000,000 to build in 2001 and would cost at least double that to replace today.

The rig represents the cutting edge of drilling technology. It is a floating rig, capable of working in up to 10,000 ft water depth. The rig is not moored; It does not use anchors because it would be too costly and too heavy to suspend this mooring load from the floating structure. Rather, a triply-redundant computer system uses satellite positioning to control powerful thrusters that keep the rig on station within a few feet of its intended location, at all times. This is called Dynamic Positioning.

The rig had apparently just finished cementing steel casing in place at depths exceeding 18,000 ft. The next operation was to suspend the well so that the rig could move to its next drilling location, the idea being that a rig would return to this well later in order to complete the work necessary to bring the well into production.

It is thought that somehow formation fluids – oil /gas – got into the wellbore and were undetected until it was too late to take action. With a floating drilling rig setup, because it moves with the waves, currents, and winds, all of the main pressure control equipment sits on the seabed – the uppermost unmoving point in the well. This pressure control equipment – the Blowout Preventers, or ‘BOP’s” as they’re called, are controlled with redundant systems from the rig. In the event of a serious emergency, there are multiple Panic Buttons to hit, and even fail-safe Deadman systems that should be automatically engaged when something of this proportion breaks out. None of them were aparently activated, suggesting that the blowout was especially swift to escalate at the surface. The flames were visible up to about
35 miles away. Not the glow – the flames. They were 200 – 300 ft high.

All of this will be investigated and it will be some months before all of the particulars are known. For now, it is enough to say that this
marvel of modern technology, which had been operating with an excellent safety record, has burned up and sunk taking souls with it. The well still is apparently flowing oil, which is appearing at the surface as a slick. They have been working with remotely operated
vehicles, or ROV’s which are essentially tethered miniature submarines with manipulator arms and other equipment that can perform work underwater while the operator sits on a vessel. These are what were used to explore the Titanic, among other things. Every floating rig has one on board and they are in constant use. In this case, they are deploying ROV’s from dedicated service vessels. They have been trying to close the well in using a specialized port on the BOP’s and a pumping arrangement on their ROV’s. They have been unsuccessful so far. Specialized pollution control vessels have been scrambled to start working the spill, skimming the oil up.

In the coming weeks they will move in at least one other rig to drill a fresh well that will intersect the blowing one at its pay zone. They will use technology that is capable of drilling from a floating rig, over 3 miles deep to an exact specific point in the earth – with a target radius of just a few feet plus or minus. Once they intersect their target, a heavy fluid will be pumped that exceeds the formation’s pressure, thus causing the flow to cease and rendering the well safe at last. It will take at least a couple of months to get this done, bringing all available technology to bear. It will be an ecological disaster if the well flows all of the while; Optimistically, it could bridge off downhole.
It’s a sad day when something like this happens to any rig, but even more so when it happens to something on the cutting edge of our capabilities. The photos that follow show the progression of events over the 36 hours from catching fire to sinking.

You may have heard the news in the last two days about the Deepwater Horizon drilling rig which caught fire, burned for two days, thensank in 5,000 ft of water in the Gulf of Mexico. There are still 11 men missing, and they are not expected to be found.The rig belongs to Transocean, the world’s biggest offshore drilling contractor. The rig was originally contracted through the year 2013 toBP and was working on BP’s Macondo exploration well when the fire broke out. The rig costs about $500,000 per day to contract. The fulldrilling spread, with helicopters and support vessels and other services, will cost closer to $1,000,000 per day to operate in the course ofdrilling for oil and gas. The rig cost about $350,000,000 to build in 2001 and would cost at least double that to replace today.The rig represents the cutting edge of drilling technology. It is a floating rig, capable of working in up to 10,000 ft water depth. The rig isnot moored; It does not use anchors because it would be too costly and too heavy to suspend this mooring load from the floatingstructure. Rather, a triply-redundant computer system uses satellite positioning to control powerful thrusters that keep the rig on stationwithin a few feet of its intended location, at all times. This is called Dynamic Positioning.The rig had apparently just finished cementing steel casing in place at depths exceeding 18,000 ft. The next operation was to suspend thewell so that the rig could move to its next drilling location, the idea being that a rig would return to this well later in order to complete thework necessary to bring the well into production.It is thought that somehow formation fluids – oil /gas – got into the wellbore and were undetected until it was too late to take action. With afloating drilling rig setup, because it moves with the waves, currents, and winds, all of the main pressure control equipment sits on theseabed – the uppermost unmoving point in the well. This pressure control equipment – the Blowout Preventers, or ‘BOP’s” as they’recalled, are controlled with redundant systems from the rig. In the event of a serious emergency, there are multiple Panic Buttons to hit,and even fail-safe Deadman systems that should be automatically engaged when something of this proportion breaks out. None of themwere aparently activated, suggesting that the blowout was especially swift to escalate at the surface. The flames were visible up to about35 miles away. Not the glow – the flames. They were 200 – 300 ft high.All of this will be investigated and it will be some months before all of the particulars are known. For now, it is enough to say that thismarvel of modern technology, which had been operating with an excellent safety record, has burned up and sunk taking souls with it.The well still is apparently flowing oil, which is appearing at the surface as a slick. They have been working with remotely operatedvehicles, or ROV’s which are essentially tethered miniature submarines with manipulator arms and other equipment that can perform workunderwater while the operator sits on a vessel. These are what were used to explore the Titanic, among other things. Every floating righas one on board and they are in constant use. In this case, they are deploying ROV’s from dedicated service vessels. They have beentrying to close the well in using a specialized port on the BOP’s and a pumping arrangement on their ROV’s. They have been unsuccessfulso far. Specialized pollution control vessels have been scrambled to start working the spill, skimming the oil up.In the coming weeks they will move in at least one other rig to drill a fresh well that will intersect the blowing one at its pay zone. They willuse technology that is capable of drilling from a floating rig, over 3 miles deep to an exact specific point in the earth – with a target radiusof just a few feet plus or minus. Once they intersect their target, a heavy fluid will be pumped that exceeds the formation’s pressure, thuscausing the flow to cease and rendering the well safe at last. It will take at least a couple of months to get this done, bringing all availabletechnology to bear. It will be an ecological disaster if the well flows all of the while; Optimistically, it could bridge off downhole.It’s a sad day when something like this happens to any rig, but even more so when it happens to something on the cutting edge of ourcapabilities. The photos that follow show the progression of events over the 36 hours from catching fire to sinking.

Usted puede haber oído la noticia sobre la plataforma de perforación en aguas profundas que se incendio, ardió durante días, luego se hundió a 5,000 pies en el Golfo de México. Todavía hay 11 hombres desaparecidos y no se espera que sean encontrados. Pertenecen a Transocean la contratista de perforación mar adentro más grande del mundo. Fue contratada originalmente hasta el año 2013 a BP y estaba trabajando en la exploración de BP Macondo cuando el fuego estalló. Los costos de perforación son de unos 500.000 dólares por día. El contrato de perforación completo, con helicópteros y buques de apoyo y otros servicios tendrá un costo cercano a $1.000.000 por día durante el tiempo que dure la extracción de petróleo y gas. El costo del equipo de perforación es de $350.000.000 de dólares y costaría hoy día al menos el doble.

El dispositivo representa la vanguardia de la tecnología de perforación. Se trata de una plataforma flotante, capaz de trabajar a unos 10.000 pies de profundidad. La plataforma no está amarrada, no utiliza anclajes ya que seria muy costoso y demasiado pesada para suspender este peso de amarres de la estructura flotante. Por el contrario, poseía un sistema informático, un sistema de posicionamiento satelital que controlaba los propulsores que mantenía la plataforma a pocos metros de su emplazamiento previsto lo que se conoce como Posicionamiento Dinámico.

El equipo de perforación había terminado de cimentar la carcasa de acero en su lugar a profundidades superiores a los 18.000 m. La siguiente operación fue la suspensión del pozo para que la plataforma pudiese trasladarse a su lugar de perforación, con la idea de que un equipo de perforación regresase a este mas adelante para terminar el trabajo. Se cree que de alguna manera los fluidos de la formación –petróleo y gas- se introdujeron en el pozo y no fueron detectados hasta que fue muy tarde para tomar las medidas de corrección. La configuración de la plataforma flotante que se mueve con las olas, corrientes y vientos todos los equipos del control principal se asentaron en el fondo del mar. Este equipo de control de presión –los preventores Blowout o “base de la pirámide” son controladas con sistemas de la plataforma. En el caso de una emergencia hay varios botones incluso sistemas de Deadman prueba de fallas que se activa automáticamente cuando algo de esta proporción se desata. Ninguno de ellos fueron activados, lo que sugiere que el golpe fue rápido y en aumento hacia la superficie. Las llamas eran visibles hasta unos 35 km. de distancia. No fue el resplandor, er4an llamas de 200 a 300 metros de altura.

Todo será investigado y en unos meses mas todos los pormenores se conocerán. Por ahora, baste decir que esta maravilla de la tecnología moderna que había estado funcionando con excelente historial de seguridad, se ha quemado y hundido.

El pozo sigue vertiendo petróleo que aparece en la superficie como una mancha. Se trabaja con vehículos manejados a control remoto o ROV que son submarinos en miniatura y otro equipo que puede realizar trabajos bajo el agua. Estos instrumentos son los que fueron utilizados para explorar el Titánic. Cada plataforma tiene uno a bordo y está en uso permanente. En este caso están desplegando ROV de uso permanente. Ellos han estado tratando de cerrar el pozo. No han tenido éxito hasta ahora. Buques especializados para el control de la contaminación han empezado a trabajar sobre el derrame.

En las próximas semanas se trasladaran al menos en una plataforma para la perforación de un pozo nuevo que permita cruzar la zona productiva para realizar una explosión. Usarán tecnología capaz de perforar un pozo de flotación de más de 3 km. De profundidad –con un radio de unos metros mas o menos. Una vez que crucen su objetivo se bombeará un líquido que supere la presión de formación causando así un flujo que permita cesar el flujo de petróleo. Tomará al menos dos meses para lograrse este resultado. Será un desastre ecológico sino se logra a tiempo su control definitivo.

Las fotos que siguen muestra la evolución de los acontecimientos durante las 36 horas siguientes al incendio.

Traducción Toustodo´s

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