National Oilwell Varco : Improving structural integrity and fatigue performance on offshore installations

Cost efficiency is a major concern for harsh environment offshore drilling and will continue to be so for the foreseeable future, and it is with this in mind that we continue to innovate with our offshore solutions. In our XL Systems business unit, we're addressing the demand for technologies that provide operators with greater structural strength and fatigue performance in applications such as jackup exploratory well conductors and subsea well conductors or jet strings.

We partnered with Walter Oil & Gas, an independent E&P company, to develop a custom version of our XLC-S™ connector for use on the Coelacanth platform, the third-tallest fixed platform in the Gulf of Mexico. Walter Oil & Gas installed a total of eight offshore conductor strings with the H&P 203 rig in 1,186 ft of water in EW Block 834, a challenging prospect because of both water depth and lithology. Our unique connector, the XLC-S-HS, was used on each 30-in. conductor string, as well as our line pipe.

Our proprietary wedge threadform on high-strength forging material that is welded straight to the pipe body meant Walter Oil & Gas received a connector solution that was stronger than the pipe in tension, compression, and bending. In addition, the only alternative to using the XLC-S-HS connector was welding, which was extremely time consuming. With an approximate spread rate of $180,000 per day, average connection times with the XLC-S-HS being 5.72 minutes per connection, and average times to weld pipe (with NDE) being 225 minutes per connection, Walter Oil & Gas saved more than USD 27,000 per connection-and more than USD 1 million per string-with our solution versus the norm.

To read more about our project with Walter Oil & Gas and other applications of our XL Systems technologies, read our feature offshore solutions article in E&P magazine.

Published Date: 2018-08-29
Source: National Oilwell Varco