Drilling Risers Make Deep Sea Oil Drilling Possible
Deep sea oil and gas drilling is a complicated affair rife with potential pitfalls. Nonetheless, it's here to stay for as long as we need massive amounts of energy to fuel the world's economies. Safe equipment and procedures are therefore essential to all deep sea drilling activities.
Drilling Risers are just one of the components of the deep sea drilling architecture which makes it a relatively safe operation. Without them, the oil and gas drilling landscape would be quite a bit different. Drilling Risers are conduits, if you will, that provide a path for mud and drilling debris to be carried to the surface instead of being discharged into the water. This is necessary for protecting the area around the site as well as preventing the drill hole from collapsing back onto itself.
There are two types of drilling risers known as Marine risers and Tie-back (or Fullbore) risers. The marine drilling riser is a flexible tube system used on floating platforms. It connects to the well's blow out preventer and runs all the way to a connection with the platform on the surface. Inherent to the floating platform is the difficulty in maintaining a safe operation during periods of rough seas. Devices called “centralizers” have been developed to aid in the deployment and recovery of drilling risers in difficult waters.
Fixed drilling platforms use the tie-back riser. It is generally a single tube whereas the marine riser usually consists of a main tube and two auxiliaries. It is also connected at the blow out preventer and runs to the stationary platform above.
Even with the two classifications of drilling risers, it would be an over-simplification to say the only differences are those listed here. Rather, every drilling situation is unique. Designers of drilling risers and their associated equipment are required to modify the basic structure of a given riser to meet the unique needs of the intended site. When a site is closed, that same riser might be modified again for use at a new site.
Engineering a drilling riser requires expertise in several areas. One must understand the principles of water pressure, material flow, ocean currents, equipment fatigue and degradation, and so on. A drilling riser engineered with one or two weaknesses could prove the source of a complete system failure. It could also mean the closing of a well; a costly event for the company doing the drilling.
The nature of deep sea oil and gas exploration has given rise to new opportunities for custom riser designs. As more and more platforms and rigs are put into service, engineers are learning more information to make drilling safer. Drilling Risers continue to be an integral part of the program.
The average consumer may never know anything about drilling risers, but he'll probably be glad to know they are performing an outstanding service on oil and gas platforms around the world, making his life that much better.