Subsea Production System Layout

[danago]

Hi. I am working on a project that requires me to have some understanding of subsea production systems (from Xmass tree to the risers) and what some of the key factors are that determine things such as the well placement, number of manifolds, manifold placement, etc. I have some knowledge of onshore facilities (mainly LNG), however I haven't delved much into what goes on below the water's surface, so much of this is new to me.

From the reading I've done, it seems that the number of wells is a big driver for things such as the number of manifolds and therefore number of rigid flowlines, PLETs, risers, etc. Given this, it probably makes sense for me to first understand why an operator would decide to drill a particular number of wells. On first though, I'd say some of the key variables are:

- Size of oil/gas field
- Desired production profile
- Connectivity of reservoirs (less connectivity = more wells)

Once this has been determined, how would an operator then go about deciding how the production from each well will be tied together and what the layout of the subsea system will be?

I know I am oversimplifying this, but I'd just like to understand what some of the key drivers for this are. Even suggestions for good further reading will be helpful.

 

[danago]

I've just had a thought that has prompted a question on a related topic: in designing the reservoir development strategy, will engineers generally decide first how many drill centres are required, and then figure out how many wells should be at each drill center? I'm sure it is a little more iterative than that, but would that capture, on a high level, the general method of logic?