Drilling Risers and Their Uses

Drilling risers are used in several different ways to connect a subsea blowout preventer stack to a surface rig.  This connection is then used to take the mud returns to the surface.  Without a drilling riser and the connection it makes, the mud would spill out of the stack and onto the seafloor.  This can cause a number of issues.  A drilling riser falls into one of two categories, a fullbore drilling riser and a marine drilling riser.  The marine drilling riser generally has a smaller diameter pie and includes choke and kill lines.  The fullbore riser does not feature any external auxiliary lines.

There are several different forms of drilling risers, and the one used in a particular case depends on the needs of the job.  Attached and pull risers are generally used with complient towers and with fixed platforms.  On the other hand, attached and pull tube risers are used with concrete gravity structures.  For floating systems and for spars, however, these solutions won’t work because lateral excursions can’t be accommodated.  Instead, steel catenary risers or flexible risers are used for floating systems, while a tope tensioned riser is usually used for spar and TLP situations.  Hybrid or riser towers can also be used for floating systems, especially in cases involving great depths.

As a leader in engineering products, Claxton Engineering has supplied drilling risers for a number of different major projects around the world.  Claxton supplies both risers and custom equipment packages that can be tailored to what the client needs.  One of the flagship services of the company is hot tapping which allows alterations to be made to a pipe without it being shut down.  Some of the major projects Claxton has been involved with include the Ganymede Project, the use of a high pressure drilling riser in Norway, and the manufacturing of production risers for use on the Ivory Coast.  These projects have all involved creating custom parts and, in some cases, creating innovative solutions based around drilling risers. 

Another project that Claxton was involved in that required great innovative thinking and creativity was the creation of a drilling riser system for a water injection project.  The challenge here was not in creating the drilling riser but in getting it done within four weeks, which was all the time left in the project schedule.  Claxton’s team of engineers came in, evaluated the problem, and turned everything around within the time necessary.  They brought in a number of different products across a range of disciplines to do it, but in the end, Claxton’s brilliant team showed exactly what they were capable of.

Drilling risers may not be something the common man will ever have to understand or deal with, but for those in the industry, they are essential pieces of machinery.  Claxton Engineering has proven their ability to create custom drilling riser packages for any situation, and their dedication to quality shines through in all of their work.