Title : Hybrid bit was the solution to decrease the invisible NPT resulted in drilling the shoe in the 6 1/8” section which enables decrease the NPT to half in Oman
Abstract:
Objectives/Scope:
Throughout last two decades petroleum drilling industry started shifting from being roller-cone bits dependent to polycrystalline diamond compacts (PDC) bits dependent. Since then, all drill bits manufacturers in the market directed the R&D towards enhancing the PDC products, which helps in having performance consistency of liner shoe track drilling out and consequently saving non-productive time (NPT).
However, still there exist very harsh/challenging drilling environments worldwide, where PDC bits are not considered as solution. Yet using roller-cone bits is time consuming because of the slow penetration rate associated and the risk of bearing/seals failure and when to pull out of hole with these bits to avoid more NPT.
Methods, Procedures, Process:
This study challenges how the Hybrid bit technology along with more modification in the BHA, drilling practices and Drive type help getting remarkable results drilling slim and small holes while reaching to the directional plan with minimal NPT , resolved directional tendencies and drilling the shoe much faster than traditional PDCs.
In 2011 the first hybrid drill bit was introduced to the market incorporating roller-cone and PDC cutting structures for such challenging applications. Such technology enabled faster drilling and accordingly allowed more intervals to be drilled within the same Krevs limits of used bearings, reducing number of trips and bits used.
Results, Observations, Conclusions:
Since then more efforts were devoted to R&D working on Hybrid bit cutting structure and bearing/seals enhancements. However, still lots of operators question the best application to use the hybrid technology and the best time to pull out with a bit without being overtly used or without wasting remaining bit life in drilling. Historically, reliability curves per field/areas were used to select Krevs limit. However, recent studies introduced the term Wn (work term) which relates the bearing/seal life to exerted loads (WOB-RPM). This term was found to be more comprehensive in defining bearing/seal life limitations per size per field/application more than reliability curves.
This paper aims to highlight how the Hybrid technology along with the other changes in the BHA benefit in decreasing the invisible NPT , decreasing the mechanical Specific Energy (MSE) in a slim horizontal application based on drilling parameters of offsets and the wells been drilled with the Hybrid bit
Novel/Additive Information:
By leveraging Hybrid bits along with the rest of the changes in the BHA, drilling engineers can achieve multiple benefits. These include better directional control, increased drilling efficiency, and enhanced overall wellbore stability. The findings of this study encourage drilling engineers to embrace hybrid bits as a strategic choice for directional drilling, particularly in applications where vibrations, long hours drilling the shoe and wellbore stability is vital.
