Maersk Oil’s Culzean project
- Expected to meet 5% of total UK gas demand at peak production in 2020/21
- Plateau production of 60,000–90,000 boepd expected
- Water depth is 88 m, drilling temperatures up to 175 degrees celsius and drilling depth is 4,500 metres
- Resources estimated at 250–300 million barrels of oil equivalent. Production is expected to start in 2019 and continue for at least 13 years with peak production in 2020/21
The extreme conditions on Culzean mean planning is paramount. Materials must be strong enough to stand up to the pressure and temperature, and safety considerations are therefore being built into the design. The overall idea is to take proven technology and hardware and expand or upgrade it to fit the project.
The “Walkinside” tour that Vissing-Jørgensen is taking with the help of an Xbox controller will allow designers to iron out inefficiencies and potential trouble spots that might not occur to them without being able to visualise the facilities as they will be in reality. That could include something as obvious and straightforward as spotting a valve that is two metres off the ground and lowering it in the final design.
The design mantra
The design is laid out with the highest focus on safety and avoiding risk to personnel, with the accommodation placed as a safe haven some 270 metres away from the wells.
Some parts used in construction of the facilities will be made using hot isostatic pressing of metal dust to create extremely strong materials, which is known as HIP Process. Highly rated hub connectors will be applied where welding is impractical.
“Keeping it simple really is a design mantra on Culzean,” says Martin Urquhart, the Project Manager. “The pressure and temperature are the complicating factors, so materials have to be much stronger to cope with both extremes. We like to use simple tried and tested methods and make decisions that build in extra safety margins wherever we can.”
Penetrating the surface
Maersk Oil has commissioned a new drilling rig for Culzean, based on an established design with specific, hi-spec additions to deal with the particular conditions, says Andrew Lough, the Wells Manager for Culzean. One of the big challenges is getting a rig cantilever – the movable structure that can allow drilling of multiple wells from a single location – which can move around easily and access all the wells that need to be drilled from one position.