Pipe-in-pipe Methodology Restores Corroded Steel Pipeline Under Major Canadian Waterway
The Challenge
Corrosion concerns caused a large oil and gas operator to shut down a major oil pipeline that ran under a Canadian waterway in an area accessible only by plane or barge. Subsequently, the company’s Integrity Management Team confirmed that a 1.86-mi (2.9-km) section of its 10-inch steel line had lost more than 70 percent of its wall thickness. To overcome this challenge, the company needed a solution that would allow them to repair the pipeline while avoiding the expense of drilling a .93 mi (1.5 km) horizontal directional bore across the river to reach it— or constructing a new pipeline altogether.
The Solution
After evaluating several pipeline solutions, the company selected FlexSteel’s 8-inch, 1,500 psi (100 bar) line pipe to help reactivate the line. FlexSteel’s pipeline system provided high-tensile strength capabilities that enabled the operator to complete five pulls across the mainland and multiple river crossings. The longest of these pulls was a 4,672 ft (1,424 m) pull under the Mackenzie River.
The Result
FlexSteel provided a stand-alone, long-term pipeline solution. By using FlexSteel’s safe and reliable pipe-in- pipe methodology to recommission the line, the operator overcame the costs of replacing the entire pipeline and eliminated previous line pipe corrosion concerns. In addition, the operator could pull long lengths of line pipe with minimal disturbance to the environment. Despite operation halts due to poor weather and high waves, the operator was able to commission the pipeline section in seven days.
