Robust Design of Rotary Steerable System RSS and Revised Drilling Procedure Deliver Superior Performance in a UAE Onshore Field.
Authors: Al Mutawa Ahmed Abdulla , Quintero Fernando , Awad Mohamad Abdul Salam , Le Khoa P. , Cantarelli Elena , Thavaraj Lambo , Dimas Miron A. , Kojadinovic Nenad 
Published: November 2017

Rotary Steerable System (RSS) has been used for quite some time in the industry and in UAE onshore fields. But as the wells become increasingly more complex operators are forced to look into upgraded technologies to expand the envelope beyond the known limits, often implying more complex and costly bottom hole assembly (BHA). At the same time the current oil price situation make it extremely difficult for operators to justify any increment of Authority for Expenditure (AFE) or to take the risk of experimenting new solutions that could potentially increase non-productive-time (NPT), even if for just limited period until the learning curve is established.

This case study demonstrates that adopting both fit for purpose technology and invisible lost time (ILT) reduction strategy can yield tremendous performance improvement delivering wells ahead of AFE.

A preliminary field analysis carried as first thing to understand the field drilling challenges and performance limiters highlighted that both on bottom (rate of penetration, ROP) and off bottom time (connection time, wiper trips, circulation time, tripping time, etc.) presented areas for improvement.

Throughout the life cycle phases of field development more complex reservoirs have been targeted for example thinner layers, multi-structural drain sections, extended laterals, etc. The demand of an RSS being able to drill smoother wellbore minimizing tortuosity and enabling longer sections and trouble-free tripping had gradually changed from being a "nice to have" feature to be a necessity not only to eliminate time waste but also to prevent costly stuck pipe events. The new high performance RSS (HP-RSS) and its enhanced software for trajectory control enabled a faster on bottom ROP by minimizing the need of directional driller intervention to correct the trajectory hence maximizing on bottom time.

The enhanced directional control translated into smoother wellbores resulting in reduced friction factors and torque and drag which eliminated the need of wiper trips and decreased tripping and connection times.

In parallel with this also drilling and connection procedure were revised, utilizing torque and drag real time monitoring to optimize connection time.

The expanded envelope of HP-RSS also enabled further improvement of hydraulics for effective hole cleaning while drilling minimizing the hole conditioning time on connection.

The advantage of having superior quality wellbore extended also to post drilling phases, for example it enabled a faster and trouble-free running of complex smart completion reducing HSE risks and further impacting AFE.

In summary, the HP-RSS enabled superior performance saving $287.5K for an invidual well. The total amount of saving projected over a year in this field is estimated to be around $ 2.9M.

Efficiency and reliability are keys to lower costs and increase profitability in oil and gas operations. This paper introduces a novel approach that aim to expand technical confidence to drilling and reservoir management to target more challenging drains sections with higher productivity.