Location: Central North Sea

Product: AQC-BC Risers, Running Tools & Centralisers

Background

Aquaterra Energy partnered with an operator in 2015 to provide drilling risers and conductor centralisers in support of the new development located in the central North Sea. The project was a high-profile new HPHT development of gas condensate production, with the field providing 5% of the UK’s gas demand once brought online in 2019. The operator sought a single source solution for the provision of a BOP quick connector package, surface drilling risers inclusive of quick connectors and conductor centralisers (specifically with a 10,000-year storm load rating). The wells presented specific technical challenges of a HPHT nature; therefore, the majority of the drilling riser equipment required a SWP rating of 15,000 PSI.

Solution

Aquaterra Energy’s awarded scope of supply included an 18-3/4” 15k AQC-BC BOP package, primary and backup 18-3/4” 5,000 PSI SWP MP risers with an AQC-BC pin top to interface with the rig BOP, primary and backup 13-5/8” 15,000 SWP HP risers with an AQC-BC top to interface with the rig BOP, an 18-3/4” 15k AQC-BC primary hydraulic running tool to facilitate the installation and retrieval of the surface risers, a backup 18-3/4” 15k AQC-BC mechanical running tool and the supply of several dozen sets of conductor centralisers for the wells installed to date.

In addition to the equipment scope of supply, we produced all necessary detailed operational procedures and risk assessments to allow for the efficient and safe installation and retrieval of the risers and for installation of the centralisers.

Results

Phase 1 of the development was successfully completed and production commenced from the field in 2018. As a direct result, the operator saved hundreds of hours in rig time by utilising the AQC-BC connectors across the BOP and risers, with make up and break out times being reduced to as little as 15 minutes per make/break, compared to API flange make up/break out of around 5 hours.
Better still, the primary hydraulic running tool performed make up and break outs in as little as 5 minutes, resulting in the risers being installed and retrieved in the most optimised method available.

The centralisers were supplied with the specified 10,000-year storm load rating; therefore they will continue to centralise the conductors for many years and minimise fatigue loading on the conductors well beyond their operational design life.