Subsea Flexible Pipelines

Significant sections of flexible pipeline within an offshore oilfield required replacement and reconfiguration. Prior to the work scope, these pipelines were degassed and filled with either an environmental barrier fluid or treated seawater. Upon completion of the works, the pipelines were leak tested, dewatered, and prepared for return to service.

Working closely with the client from the planning stage, SANCCUS came up with the solution which combines the use of Pipeline Gels and Gel Pigs to efficiently meet all operational requirements.

Solution

Result

Glycostat Gel successfully achieved both effective degassing and the formation of a robust environmental barrier, enabling safe replacement and reconfiguration activities across multiple flexible pipeline sections.

M-Gel Pig demonstrated excellent performance by reliably traversing flexible pipelines with corrugated internal surfaces, without obstruction or degradation. Following replacement, the pipelines were leak tested and efficiently dewatered, leaving the system clean, dry, and fully prepared to be returned to service.

Value

By combining Pipeline Gels and Gel Pigs into a single, integrated methodology, SANCCUS fulfilled 3 critical objectives:

1. Degassing of flexible pipelines
2. Provision of a reliable environmental barrier
3. Dewatering following installation and leak testing

This approach significantly simplified offshore execution and reduced vessel time and operational complexity.

The project highlighted the unique capability of SANCCUS Gel technology to perform predictably within flexible pipelines - often considered challenging for conventional pigging - reinforcing its value for complex subsea operations.